NORTHWEST PIPE CO - Annual Report: 2006 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

For the Fiscal Year Ended: December 31, 2006

OR

For the transition period from              to             

Commission File Number: 0-27140

NORTHWEST PIPE COMPANY

(Exact name of registrant as specified in its charter)

200 S. W. Market Street

Portland, Oregon 97201

(Address of principal executive offices and zip code)

503-946-1200

(Registrant’s telephone number including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ¨    No  x

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ¨    No  x

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K, or any amendment to this Form 10-K.  x

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer” and “large accelerated filer” in Rule 12b-2 of the Act. (Check one):

Large accelerated filer  ¨                    Accelerated filer  x                    Non-accelerated filer  ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  x

The aggregate market value of the common equity that was held by non-affiliates of the Registrant was $166,530,318 as of June 30, 2006 based upon the last sales price as reported by Nasdaq.

The number of shares outstanding of the Registrant’s Common Stock as of March 15, 2007 was 8,933,593 shares.

Documents Incorporated by Reference

The Registrant has incorporated into Parts II and III of Form 10-K by reference portions of its Proxy Statement for its 2007 Annual Meeting of Shareholders.

Table of Contents

NORTHWEST PIPE COMPANY

2006 ANNUAL REPORT ON FORM 10-K

TABLE OF CONTENTS

Table of Contents

PART I

We are a leading North American manufacturer of large-diameter, high-pressure steel pipeline systems for use in water infrastructure applications, primarily related to drinking water systems. Our pipeline systems are also used for hydroelectric power systems, wastewater systems and other applications. With a history that dates back more than 100 years, we have established a leading position based on a strong, widely recognized reputation for quality and service and an extensive array of product offerings. Our manufacturing facilities are strategically located throughout North America to provide us with broad geographic coverage of our target markets, giving us competitive advantages in serving our customers.

We manufacture water infrastructure products through our Water Transmission Group, which in 2006 generated approximately 71% of our net sales. We market our water infrastructure products through an in-house sales force comprised of sales representatives, engineers and support personnel who work closely with public water agencies, contractors and engineering firms, often years in advance of projects being bid. This allows us to not only identify and evaluate planned projects at early stages, but also to participate in the engineering and design process and ultimately promote the advantages of our systems. Our sales have historically been driven by the need for new water infrastructure, which is based primarily on overall population growth and population movement between regions. We believe the need for new water infrastructure will continue to be a significant growth driver for us and, importantly, will be accompanied by the increasing need for water infrastructure upgrades, repairs and replacements due to the aging and outdated water infrastructure systems throughout North America.

In addition to manufacturing water infrastructure products, we also manufacture other welded steel products through our Tubular Products Group and our Fabricated Products Group, which in 2006 generated approximately 24% and 5%, respectively, of our net sales. Our Tubular Products Group has the capability to manufacture a broad array of small-diameter, ERW steel pipe for use in a wide range of applications, including construction, agricultural, industrial, energy and traffic signpost systems. Our Fabricated Products Group manufactures a variety of aboveground and underground liquid propane storage tanks for residential, commercial and industrial applications. Over the past year, our Fabricated Products Group has developed several new products that we are currently marketing to OEMs in the transportation, energy and water industries.

Our Industries

Water Transmission. The U.S. market for water delivery equipment and systems is estimated to be approximately $11 billion annually. Within this market, we focus on engineered pipeline systems that utilize large-diameter, high-pressure steel pipe. In addition to these water infrastructure applications, our Water Transmission Group manufactures products for certain structural piling applications and in-plant pipeline systems for power plants and other industrial applications. We believe the current addressable market for the products sold by our Water Transmission Group is approximately $750 million to $850 million. Our core market is the large-diameter, high-pressure portion of the pipeline that is typically at the “upper end” of a pipeline system. This is the portion of the overall water pipeline that generally transports water from the source to a treatment plant or from a treatment plant into the distribution system, rather than the small lines that deliver water directly into households. However, we also have the ability to produce small-diameter pipe.

A combination of population growth and movement to new population centers, substantial underinvestment in water infrastructure over the past several decades and an increasingly stringent regulatory environment are driving considerable and growing demand for water infrastructure products in the United States. These trends are increasing the need for new water infrastructure as well as the need to upgrade, repair and replace existing water infrastructure, which we believe will significantly increase the demand for our water infrastructure products and other products related to water transmission and distribution.

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The primary drivers of growth in new water infrastructure installation are population growth and movement. According to the U.S. Census Bureau, the population of the United States will increase by over 80 million people between 2000 and 2030. The resulting increase in demand will require substantial new infrastructure, as the existing U.S. water infrastructure is not equipped to provide water to millions of new residents. The combination of population growth and movement is projected to result in more than 70 million new residents in the southern and western regions of the United States. Our manufacturing facilities are well located to take advantage of the anticipated growth in these regions.

Many authorities, including the EPA, believe the U.S. water infrastructure is in critical need of an update. With the average age of water transmission pipes in the United States approaching 70 years, much of the U.S. water infrastructure is antiquated and requires upgrade, repair or replacement. Some water transmission pipelines in the United States are over 100 years old, and the American Society of Civil Engineers has given poor ratings to many aspects of the U.S. water infrastructure in a recent study. By 2020, approximately 44% of the water pipe in the United States will be classified as “poor” to “life-elapsed” if renewal or replacement of the existing infrastructure does not occur. In its third national assessment of public water system infrastructure, the EPA in 2005 estimated that a total investment of approximately $277 billion will be needed to install, upgrade and replace infrastructure over the next 20 years. The EPA estimates that approximately $184 billion of this needed investment applies to the rehabilitation or replacement of deteriorated or undersized water transmission and distribution infrastructure.

Increased public awareness of problems with the quality of drinking water and efficient water usage has resulted in more stringent application of federal and state environmental regulations. The need to comply with these regulations in an environment of heightened public awareness towards water issues is expected to contribute significantly to growth in the water infrastructure industry over the next several years. Water systems will need to be installed, upgraded and replaced in order to satisfy these water quality laws and regulations while overall demand for water continues to increase.

Tubular Products. The tubular products industry encompasses a wide variety of products serving a diverse group of end markets. We have been active in several of these markets, including fence framework, mechanical tubing, agriculture, energy, traffic signpost systems, fire protection sprinkler systems and structural tubing. Currently, we are focusing our efforts on products for which we believe we have sustainable advantages, and we are reducing our production of commodity products that are subject to heavy import competition. Within our focus markets, we believe both traffic signpost systems and energy products offer significant growth opportunities. We manufacture several different signpost systems and believe this business will grow over the next several years as our systems become adopted in additional states and jurisdictions. Our sales to the energy market have grown substantially in the past two years. We are currently manufacturing products for the energy market under a marketing agreement with Lone Star Steel and expect to see continued growth in sales as we expand this product line.

Fabricated Products. The overall metal fabrication industry is extremely diverse, covering a wide range of products and end markets. Within this industry, our Fabricated Products Group currently focuses on propane tanks. Our tanks, ranging in size from 120 gallons to 1,000 gallons, comprise the vast majority of our production today. Propane tanks are sold to gas dealers for home heating, agricultural and light industrial applications. Over the past two years, we have diversified into other segments of the broader metal fabrication industry and now offer tanks and other metal components to OEMs. Examples of these products include components used in industrial heat exchangers, tanks used for compressed air systems, specialty vessels used in material handling systems and tanks used in oil and gas processing. We are also evaluating several opportunities that will provide components for medium and heavy trucks.

Products

Water Transmission Products. Water transmission pipe is used for high-pressure applications, typically requiring pipe to withstand pressures in excess of 150 pounds per square inch. Most of our water transmission

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products are made to custom specifications and are for fully engineered, large diameter, high-pressure water infrastructure systems. Other uses include pipe for piling and hydroelectric projects, wastewater transmission, treatment plants and other applications. We have the capability to manufacture water transmission pipe in diameters ranging from 4.5 inches to 156 inches with wall thickness of 0.135 inches to 3.00 inches. We can coat and/or line these products with cement mortar, polyethylene tape, paints, epoxies, Pritec^® and coal tar enamel according to our customers’ specifications. We maintain fabrication facilities that provide installation contractors with custom fabricated sections as well as straight pipe sections. We typically deliver a complete pipeline system to the installation contractor.

Tubular Products. Our tubular products range in size from 0.50 inches to 16 inches in diameter with wall thickness from 0.035 inches to 0.315 inches. These products are typically sold to distributors or original equipment manufacturers and are used for a wide variety of applications, including water well casing, fire protection, energy, fence, traffic signpost systems, and agricultural products.

Fabricated Products. Our Fabricated Products Group produces propane tanks, which range in capacity from 120 gallons to 1,000 gallons, as well as a wide range of other fabricated metal products. We can cut, weld, burn, form, inspect and coat fabricated steel and aluminum. Propane tanks are sold to gas dealers for home heating, agricultural and light industrial applications. Other fabricated metal products such as air receivers, custom pressure vessels and components for other OEMs are currently targeted to the transportation, energy and water industries.

Marketing

Water Transmission. The primary customers for water transmission products are installation contractors for projects funded by public water agencies. Our plant locations in Oregon, Colorado, California, West Virginia and Texas allow us to efficiently serve customers throughout the United States, as well as Canada and Mexico. Our water transmission marketing strategy emphasizes early identification of potential water projects, promotion of specifications consistent with our capabilities and close contact with the project designers and owners throughout the design phase. Our in-house sales force is comprised of sales representatives, engineers and support personnel who work closely with public water agencies, contractors and engineering firms, often years in advance of projects being bid. This allows us to not only identify and evaluate planned projects at early stages, but also to participate in the engineering and design process and ultimately promote the advantages of our systems. After an agency completes a design, they publicize the upcoming bid for a water transmission project. We then obtain detailed plans and develop our estimate for the pipe portion of the project. We typically bid to installation contractors who include our bid in their proposals to public water agencies. A public water agency generally awards the entire project to the contractor with the lowest responsive bid.

Tubular Products. Our tubular products are marketed through a network of direct sales force personnel and independent distributors in the United States, Canada and Mexico. Our tubular product facilities are located in Kansas, Texas, Oregon and Louisiana. Our marketing strategy focuses on customer service and customer relationships. For example, we are willing to sell in small lot sizes and are able to provide mixed truckloads of finished products to our customers. Our tubular products are primarily sold to distributors, although we also sell to OEMs to a lesser extent. In addition, we sell these products through a strategic marketing agreement with Lone Star Steel. Our sales effort emphasizes regular personal contact with current and potential customers. We supplement this effort with targeted advertising and brochures and participation in trade shows.

Fabricated Products. Currently, our primary customers for our fabricated products are propane gas marketers. We sell our propane tanks through our direct sales force, which is augmented by a network of independent agents. Inventory is maintained at approximately 15 stocking facilities located in our key geographical markets. Our marketing strategies include regular customer visits, limited print advertising and attendance at industry trade events and expositions. State propane gas associations are influential in this industry. Consequently, we are members of these organizations and support these events in our key territories, which are the midwestern and the southeastern United States.

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As our fabricated product line continues its expansion, the transportation, energy and water industries will become larger factors in our marketing efforts. We employ a direct selling strategy for these products.

Manufacturing

Water Transmission. Water transmission manufacturing begins with the preparation of engineered drawings of each unique piece of pipe in a project. These drawings are prepared on our proprietary computer-aided design system and are used as blueprints for the manufacture of the pipe. After the drawings are completed and approved, manufacturing begins by feeding steel coil continuously at a specified angle into a spiral weld mill which cold forms the band into a tubular configuration with a spiral seam. Automated arc welders, positioned on both the inside and the outside of the tube, are used to weld the seam. The welded tube is then cut at the specified length. After completion of the forming and welding phases, the finished cylinder is tested and inspected in accordance with project specifications, which may include 100% radiographic analysis of the weld seam. The cylinders are then coated and lined as specified. Possible coatings include coal tar enamel, polyethylene tape, polyurethane paint, epoxies, Pritec^® and cement mortar. Linings may be cement mortar, polyurethane or epoxies. Following coating and lining, certain pieces may be custom fabricated as required for the project. This process is performed in our fabrication facilities. The pipe is final inspected and prepared for shipment. We ship our products to project sites principally by truck and rail.

Tubular Products. Tubular products are manufactured by the ERW process in diameters ranging from 0.50 inches to 16 inches. This process begins by unrolling and slitting steel coils into narrower bands sized to the circumference of the finished product. Each band is re-coiled and fed into the material handling equipment at the front end of the ERW mill and fed through a series of rolls that cold-form it into a tubular configuration. The resultant tube is welded by high-frequency electric resistance welders. Some products are reconfigured into rectangular and square shapes and then cut into the appropriate lengths. After exiting the mill, the products are straightened, inspected, tested and end-finished. Certain products are coated.

Fabricated Products. Propane tanks begin with hot rolled steel, from which cylinders are rolled and welded, and tank heads are drawn on a hydraulic press. After assembly and final welding, propane tanks receive both radiographic and hydrostatic testing. Lastly, the propane tanks are powder coated, and purged with a vacuum process. Other fabricated metal products typically begin with hot rolled steel, from which the steel is cut or burned to the desired dimension. The product is then formed either with a rolling or press brake process. Pieces are welded into a final assembly using a variety of welding processes and certain products are coated.

Technology. Advances in technology help us produce high quality products at competitive prices. Ongoing investments in technological improvements include an in-house metallurgical laboratory complete with state of the art optics, spectrographic analysis and impact testing capabilities. This laboratory serves as a tool for accurate process control as well as for research and development of new products and processes. Finished products also benefit from recent advancements in nondestructive inspection systems, including phased array ultrasonics and real time imaging enhancement capabilities. To stay current with technological developments in the United States and abroad, we participate in trade shows, industry associations, research projects and vendor trials of new products.

Quality Assurance. We have in place quality management systems that emphasize continual improvement and that assure we consistently provide products that meet or exceed customer and applicable regulatory requirements. The Quality Assurance department reports directly to the chief executive officer. All of our quality management systems in the United States are registered by the International Organization for Standardization, or ISO, under a multi-site registration. Our Monterrey, Mexico facility is expected to be registered by the end of 2007. In addition to ISO qualification, the American Institute of Steel Construction, American Petroleum Institute, American Society for Mechanical Engineers, Factory Mutual, National Sanitary Foundation, and Underwriters Laboratory have certified us for specific products or operations. The Quality Assurance department is responsible for monitoring and measuring characteristics of the product. Inspection capabilities include, but are

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not limited to, visual, dimensional, liquid penetrant, magnetic particle, hydrostatic, ultrasonic, phased array ultrasonics, real-time imaging enhancement, real-time radioscopic, base material tensile, yield and elongation, sand sieve analysis, coal-tar penetration, concrete compression, lining and coating dry film thickness, adhesion, absorption, guided bend, charpy impact, hardness, metallurgical examinations, chemical analysis, spectrographic analysis and finished product final inspection. Product is not released for shipment to our customers until verification that all product requirements have been met.

Product Liability. The manufacturing and use of our products involves a variety of risks. Certain losses may result, or be alleged to result, from defects in our products, thereby subjecting us to claims for damages, including consequential damages. We warrant our products to be free of certain defects for one year. We maintain insurance coverage against potential product liability claims in the amount of $52 million, which we believe to be adequate. However, there can be no assurance that product liability claims exceeding our insurance coverage will not be experienced in the future or that we will be able to maintain such insurance with adequate coverage.

Backlog

Our backlog includes confirmed orders, including the balance of projects in process, and projects for which we have been notified we are the successful bidder even though a binding agreement has not been executed. Projects for which a binding contract has not been executed could be canceled. Binding orders received by us may also be subject to cancellation or postponement; however, cancellation would generally obligate the customer to pay the costs incurred by us. As of December 31, 2006 and 2005, our backlog of orders was approximately $198.2 million and $125.6 million, respectively. Binding contracts had been executed for all of the projects included in the backlog at December 31, 2006 as of March 15, 2007. Backlog as of any particular date may not be indicative of actual operating results for any fiscal period. There can be no assurance that any amount of backlog ultimately will be realized.

Competition

Water Transmission. We have several competitors in the water transmission business. Most water transmission projects are competitively bid and price competition is vigorous. Price competition may reduce the gross margin on sales, which may adversely affect overall profitability. Other competitive factors include timely delivery, ability to meet customized specifications and high freight costs which may limit the ability of manufacturers located in other market areas to compete with us. With water transmission manufacturing facilities in Oregon, Colorado, California, West Virginia and Texas, we believe we can more effectively compete throughout the United States, Canada and Mexico. Our primary competitors in the water transmission business in the western United States and southwestern Canada are Ameron International, Inc. and Continental Pipe Manufacturing Company. East of the Rocky Mountains, our primary competition includes: American Cast Iron Pipe Company, McWane Cast Iron Pipe Company and Mueller Water Products, all of which manufacture ductile iron pipe; American Spiral Weld Pipe Company, which manufactures spiral welded steel pipe; and Hanson Concrete Products, Inc., which manufactures concrete cylinder pipe and spiral welded steel pipe.

No assurance can be given that other new or existing competitors will not establish new facilities or expand capacity within our market areas. New or expanded facilities or new competitors could have a material adverse effect on our ability to capture market share and maintain product pricing.

Tubular Products. The market for tubular products is highly fragmented and diversified with over 100 manufacturers in the United States and a number of foreign-based manufacturers that export such pipe into the United States. Manufacturers compete with one another primarily on the basis of price, established business relationships, customer service and delivery. In some of the sectors within the tubular products industry, competition may be less vigorous due to the existence of a relatively small number of companies with the capabilities to manufacture certain products. In particular, we operate in a variety of different markets that

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require pipe with lighter wall thickness in relation to diameter than many of our competitors can manufacture. In our markets, we typically compete with Valmont Industries, Inc., Lindsay Manufacturing Co., Tenaris, Allied Tube and Conduit Corp. and John Maneely Company, as well as imported products.

Fabricated Products. In the propane tank market, we compete against several other tank manufacturers, generally on the basis of price, delivery and customer service. Propane tanks are typically sold in truckload quantities and delivered by common carriers, and accordingly, freight is a significant component of the total delivered cost. From our Monterrey facility, we effectively cover approximately 80% of the continental United States and selected provinces in Canada. Our primary competitors are American Welding & Tank Co. (a division of Harsco Corporation), Trinity Industries, Inc. and Quality Steel Corporation. Periodically other Mexico-based producers sell into the United States, but we believe they are not a significant factor in these markets.

With other fabricated metal products, we compete against hundreds of independent fabricators, as well as internal departments of large original equipment manufacturers. Competition is vigorous for product which has little value added, and is lessened in products with greater engineering content or intellectual property.

Raw Materials and Supplies

We purchase hot rolled and galvanized steel coil from both domestic and foreign steel mills. Domestic suppliers include California Steel Industries, Inc., Beta Steel Corp., Mittal Steel Company, Nucor Corporation, and U.S. Steel Corporation. Purchases from foreign mills are conducted through international trading companies, including Marubeni Corporation, MAN Ferrostaal, and Duferco Farrell. We order steel according to our business forecasts for our Tubular Products and Fabricated Products businesses. Steel for the Water Transmission business is normally purchased only after a project has been awarded to us. From time to time, we may purchase additional steel when it is available at favorable prices. Purchased steel represents a substantial portion of our cost of sales. The steel industry is highly cyclical in nature and steel prices are influenced by numerous factors beyond our control, including general economic conditions, availability of raw materials, energy costs, import duties, other trade restrictions and currency exchange rates.

We also rely on certain suppliers of coating materials, lining materials and certain custom fabricated items. We have at least two suppliers for most of our raw materials. We believe our relationships with our suppliers are positive and have no indication that we will experience shortages of raw materials or components essential to our production processes or that we will be forced to seek alternative sources of supply. Any shortages of raw materials may result in production delays and costs, which could have a material adverse effect on our business, financial condition and results of operations.

Environmental and Occupational Safety and Health Regulation

We are subject to federal, state, local and foreign environmental and occupational safety and health laws and regulations, violation of which could lead to fines, penalties, other civil sanctions or criminal sanctions. These environmental laws and regulations govern emissions to air; discharges to water (including stormwater); and the generation, handling, storage, transportation, treatment and disposal of waste materials. We are also subject to environmental laws requiring the investigation and cleanup of environmental contamination at properties we presently own or operate and at third-party disposal or treatment facilities to which these sites send or arrange to send hazardous waste. For example, we have been identified as a potentially responsible party at various Superfund sites, including the Portland Harbor Site discussed under “Legal Proceedings” below. We believe we are in material compliance with these laws and regulations and do not currently believe that future compliance with such laws and regulations will have a material adverse effect on our results of operations or financial condition.

We operate under numerous governmental permits and licenses relating to air emissions, stormwater run-off, and other matters. We are not aware of any current material violations or citations relating to any of these permits or licenses. We have a policy of reducing consumption of hazardous materials in our operations by substituting non-hazardous materials when possible.

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We are aware of contamination at some of our properties, and additional sites could arise in the future. Based on our assessment of potential liability, we have no reserves for environmental investigations and cleanup. However, estimating liabilities for environmental investigations and cleanup is complex and dependent upon a number of factors beyond our control and which may change dramatically. Accordingly, although we believe our reserve position is adequate based on current information, we cannot assure you that our future environmental investigation and cleanup costs and liabilities will not result in a material expense. During 2006, we did not make any material capital expenditures relating primarily to environmental compliance.

We could be subject to various enforcement matters with federal, state, local and foreign regulators regarding our compliance with environmental and occupational safety and health laws and regulations. We are not aware of any current material enforcement matters.

Employees

As of December 31, 2006, we had 1,185 full-time employees. Approximately 23% were salaried and approximately 77% were employed on an hourly basis. A union represents all of the hourly employees at our Monterrey, Mexico facility. All other employees are non-union. We consider our relations with our employees to be good.

Available Information

Our internet website address is www.nwpipe.com. Our Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 are available through our internet website as soon as reasonably practical after we electronically file such material with, or furnish it to, the Securities and Exchange Commission. Our internet website and the information contained therein or connected thereto are not intended to be incorporated into this Annual Report on Form 10-K.

Additionally, the public may read and copy any materials we file with the SEC at the SEC’s Public Reference Room at 450 Fifth Street, N.W., Washington D.C. 20549. The public may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at www.sec.gov.

Following are the key risk factors that have affected our net sales and net income in the past and could materially impact our future net sales and net income:

A downturn in government spending related to public water transmission projects would adversely affect our business. Our water transmission business accounted for approximately 71% of our net sales in 2006. Our water transmission business is primarily dependent upon spending on public water transmission projects, including water infrastructure upgrades, repairs and replacement and new water infrastructure spending, which, in turn, depends on, among other things:

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Decreases in the number or government funding of public water transmission projects would adversely affect our business, financial condition and results of operations.

Project delays in public water transmission projects could adversely affect our business. The public water agencies constructing water transmission projects generally announce the projects well in advance of the bidding and construction process. It is not unusual for projects to be delayed and rescheduled. Projects are delayed and rescheduled for a number of reasons, including changes in project priorities, difficulties in complying with environmental and other government regulations and additional time required to acquire rights-of-way or property rights. Delays in public water transmission projects may occur with too little notice to allow us to replace those projects in our manufacturing schedules. As a result, our business, financial condition and results of operations may be adversely affected by unplanned downtime.

We operate in highly competitive industries, and increased competition could reduce our gross profit and net income. We face significant competition in all of our businesses. Orders in the water transmission business are competitively bid, and price competition can be vigorous. Price competition may reduce the gross margin on sales, which may adversely affect overall profitability. Other competitive factors include timely delivery, ability to meet customized specifications and high freight costs. Although our water transmission manufacturing facilities in Oregon, Colorado, California, West Virginia and Texas allow us to compete effectively throughout the United States, Canada and Mexico, we cannot assure you that new or existing competitors will not establish new facilities or expand capacity within our market areas. New or expanded facilities or new competitors could have a material adverse effect on our ability to capture market share and maintain product pricing in our water transmission business. There are many competitors in the tubular products and fabricated products businesses, and price is often a prime consideration for purchase of our products. Price competition may reduce our gross profit, which may adversely affect our net income. Some of our competitors have greater financial, technical and marketing resources than we do. We cannot assure you that we will be able to compete successfully with our competitors. Failure to compete successfully could reduce our gross profit and net income, as well as have a material adverse effect on our business, financial condition and results of operations.

Operating problems in our business could adversely affect our business, financial condition and results of operations. Our manufacturing operations are subject to typical hazards and risks relating to the manufacture of products such as:

The occurrence of any of these operating problems at our facilities may have a material adverse effect on the productivity and profitability of a particular manufacturing facility or on our operations as a whole, during and after the period of these operating difficulties. These operating problems may also cause personal injury and loss of life, severe damage to or destruction of property and equipment, and environmental damage. In addition, individuals could seek damages for alleged personal injury or property damage. Furthermore, we could be subject to present and future claims with respect to workplace exposure, workers’ compensation and other matters. Although we maintain property and casualty insurance of the types and in the amounts that we believe are customary for our industries, we cannot assure you that our insurance coverage will be adequate for liability that may be ultimately incurred or that such coverage will continue to be available to us on commercially reasonable terms. Any claims that result in liability exceeding our insurance coverage could have an adverse effect on our business, financial condition and results of operations.

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Our water transmission business faces competition from concrete and ductile iron pipe manufacturers. Water transmission pipe is manufactured generally from steel, concrete or ductile iron. Each pipe material has advantages and disadvantages. Steel and concrete are more common materials for larger diameter water transmission pipelines because ductile iron pipe generally is limited in diameter due to its manufacturing process. The public agencies and engineers who determine the specifications for water transmission projects analyze these pipe materials for suitability for each project. Individual project circumstances normally dictate the preferred material. If we experience cost increases in raw materials, labor and overhead specific to our industry or the location of our facilities, while competing products or companies do not experience similar changes, we could experience an adverse change in the demand, price and profitability of our products, which could have a material adverse effect on our business, financial condition and results of operations.

Our quarterly results of operations are subject to significant fluctuation. Our net sales and operating results may fluctuate significantly from quarter to quarter due to a number of factors, including:

Results of operations in any period are not indicative of results for any future period, and comparisons between any two periods may not be meaningful.

We depend on our senior management team, and the loss of any member could adversely affect our operations. Our success depends on the management and leadership skills of our senior management team. The loss of any of these individuals, particularly Brian W. Dunham, our president and chief executive officer, or our inability to attract, retain and maintain additional personnel, could prevent us from fully implementing our business strategy. We cannot assure you that we will be able to retain our existing senior management personnel or to attract qualified personnel when needed. We have not entered into employment agreements with any of our senior management personnel.

The success of our business is affected by general economic conditions, and our business may be adversely affected by an economic slowdown or recession. Periods of economic slowdown or recession in the United States, or the public perception that one may occur, could decrease the demand for our products, affect the price of our products and adversely impact our business. We have been impacted in the past by the general slowing of the economy and any future economic slowdowns could have an adverse impact on our business, financial condition and results of operations.

Fluctuations in steel prices may affect our future results of operations. Purchased steel represents a substantial portion of our cost of sales, particularly in our tubular products and fabricated products businesses. The steel industry is highly cyclical in nature, and, at times, pricing can be highly volatile due to a number of factors beyond our control, including general economic conditions, import duties, other trade restrictions and currency exchange rates. This volatility can significantly affect our gross profit. Although we seek to recover increases in steel prices through price increases in our products, we have not always been completely successful. For example, in 2003, when the price of steel increased, we were unable to pass along the price increase to our customers, which adversely affected our results of operations. Any similar increase in steel prices that is not offset by an increase in our prices could have an adverse effect on our business, financial condition and results of operations.

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We may be subject to claims for damages for defective products, which could adversely affect our business, financial condition and results of operations. We warrant our products to be free of certain defects. Losses may result or be alleged to result from defects in our products, which could subject us to claims for damages, including consequential damages. For example, in July 2004, we settled a product liability class action suit relating to small-diameter, thin walled fire sprinkler pipe. Pursuant to the terms of the settlement, if the remaining insurance funds of approximately $2.5 million are exhausted, we would be obligated to pay class members who have a qualifying leak at any time from July 7, 2004 to July 7, 2019 an aggregate of up to $500,000 per year for qualifying claims (or up to $1.0 million per year in the three years following July 7, 2019 for qualifying claims previously submitted). We cannot assure you that we will not experience any material product liability losses in the future or that we will not incur significant costs to defend such claims. While we currently have product liability insurance, we cannot assure you that our product liability insurance coverage will be adequate for liability that may be ultimately incurred or that such coverage will continue to be available to us on commercially reasonable terms. Any claims relating to defective products that result in liability exceeding our insurance coverage could have an adverse effect on our business, financial condition and results of operations.

Sustained increases in fuel costs could have an adverse impact on our profitability. We have recently experienced significant increases in fuel costs as a result primarily of macro-economic factors beyond our control. The price of fuel fluctuates significantly over time, and events beyond our control such as natural disasters could adversely affect the supply and cost of fuel. Although we seek to recover increases in fuel costs through price increases in our products, we have not always been completely successful. Any increase in fuel costs that is not offset by increases in our prices could have an adverse impact on our business, financial condition and results of operations.

Our products might not obtain necessary approvals or achieve market acceptance, which could adversely affect our growth. We will continue to actively seek to develop new products and to expand our existing products into new markets, but we cannot assure you that we will be successful in these efforts. In the traffic signpost systems market, our products generally have to be approved by governmental agencies, and we cannot assure you that we will be able to obtain or maintain such approval. If we are unsuccessful in developing and marketing new products, expanding into new markets, or we do not obtain or maintain requisite approvals for our products, the demand for our products will be adversely affected, which could adversely affect our business, financial condition and results of operations.

We have foreign operations, which exposes us to the risks of doing business abroad. Our fabricated products are manufactured at our Monterrey, Mexico facility, primarily for export to the United States. Any material changes in the quotas, regulations or duties on imports imposed by the U.S. government and its agencies or on exports imposed by Mexico and its agencies could adversely affect our operations in Mexico.

We also sell some of our products internationally, and part of our business strategy contemplates international growth. Our foreign activities are also subject to various other risks of doing business in a foreign country, including:

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Although our operations have not been materially affected by any such factors to date, no assurance can be given that our operations may not be adversely affected in the future. Any of these events could have an adverse effect on our operations in the future by reducing the demand for our products and services, decreasing the prices at which we can sell our products or otherwise having an adverse effect on our business, financial condition or results of operations. We cannot assure you that we will continue to operate in compliance with applicable customs, currency exchange control regulations, transfer pricing regulations or any other laws or regulations to which we may be subject. We also cannot assure you that these customs, regulations or laws will not be modified.

We have a significant amount of outstanding debt. We have financed our operations through cash flow from operations, available borrowings and other financing arrangements. As of December 31, 2006, we had approximately $100.6 million of outstanding debt.

Our high level of debt and our debt service obligations could:

Our ability to make scheduled payments on our debt will depend on our future operating performance and cash flow, which are subject to prevailing economic conditions, prevailing interest rate levels and other financial, competitive and business factors, many of which are beyond our control.

Additionally, the agreements governing our outstanding debt include financial and other restrictive covenants that impose certain requirements with respect to our financial condition and results of operations and general business activities. These covenants could adversely affect us by limiting our ability to plan for or react to market conditions or to meet our capital needs. These covenants require us to maintain certain financial ratios and place restrictions on, among other things, our ability to incur certain additional debt and to create liens or other encumbrances on assets. A failure to comply with the requirements of these covenants, if not waived or cured, could permit acceleration of the related debt and acceleration of debt under other instruments that include cross-acceleration or cross-default provisions. If any of our debt is accelerated, we cannot assure you that we would have sufficient assets to repay such debt or that we would be able to refinance such debt on commercially reasonable terms or at all.

Our backlog is subject to reduction and cancellation. Backlog represents products or services that our customers have committed by contract to purchase from us. Our backlog as of December 31, 2006 was $198.2 million. Our backlog is subject to fluctuations and is not necessarily indicative of future sales. Moreover, cancellations of purchase orders or reductions of product quantities could materially reduce our backlog and, consequently, future revenues. Our failure to replace canceled or reduced backlog could result in lower revenues, which could adversely affect our business, financial condition and results of operations.

Our tubular products business faces intense competition from imports. The level of imports of tubular products significantly impacts the domestic tubular products market. High levels of imports may reduce the volume of tubular products sold by domestic producers and depress selling prices of tubular products. We believe

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import levels are affected by, among other things, overall worldwide demand for tubular products, the trade practices of foreign governments, government subsidies to foreign producers and governmentally imposed trade restrictions in the United States. Increased imports of tubular products in the United States and Canada could adversely affect our business, financial condition and results of operations.

We are subject to stringent environmental and health and safety laws, which may require us to incur substantial compliance and remediation costs, thereby reducing our profits. We are subject to many federal, state, local and foreign environmental and health and safety laws and regulations, particularly with respect to the use, handling, treatment, storage, discharge and disposal of substances and hazardous wastes used or generated in our manufacturing processes. Compliance with these laws and regulations is a significant factor in our business. We have incurred and expect to continue to incur significant expenditures to comply with applicable environmental laws and regulations. Our failure to comply with applicable environmental laws and regulations and permit requirements could result in civil or criminal fines or penalties or enforcement actions, including regulatory or judicial orders enjoining or curtailing operations or requiring corrective measures, installation of pollution control equipment or remedial actions.

We are currently, and may in the future be, required to incur costs relating to the investigation or remediation of property, including property where we have disposed of our waste, and for addressing environmental conditions, including, but not limited to, the issues associated with our Portland, Oregon facility as discussed in “Business—Legal Proceedings” below. Some environmental laws and regulations impose liability and responsibility on present and former owners, operators or users of facilities and sites for contamination at such facilities and sites without regard to causation or knowledge of contamination. Consequently, we cannot assure you that existing or future circumstances, the development of new facts or the failure of third parties to address contamination at current or former facilities or properties will not require significant expenditures by us.

We expect to continue to be subject to increasingly stringent environmental and health and safety laws and regulations. It is difficult to predict the future interpretation and development of environmental and health and safety laws and regulations or their impact on our future earnings and operations. We anticipate that compliance will continue to require capital expenditures and operating costs. Any increase in these costs, or unanticipated liabilities arising, for example, out of discovery of previously unknown conditions or more aggressive enforcement actions, could adversely affect our results of operations, and there is no assurance that they will not exceed our reserves or have a material adverse effect on our business, financial condition and results of operations.

We face risks in connection with potential acquisitions. Acquiring businesses that complement or expand our operations has been an important element of our business strategy in the past. Although we have not completed an acquisition since 1999, we continue to evaluate potential acquisitions that may expand and complement our business. We may not be able to successfully identify attractive acquisition candidates or negotiate favorable terms in the future. Furthermore, our ability to effectively integrate any future acquisitions will depend on, among other things, the adequacy of our implementation plans, the ability of our management to oversee and operate effectively the combined operations and our ability to achieve desired operational efficiencies. If we are unable to successfully integrate the operations of any businesses that we may acquire in the future, our business, financial condition and results of operations could be adversely affected.

The relatively low trading volume of our common stock may limit your ability to sell your shares. Although our shares of common stock are listed on the Nasdaq Global Select Market, our average daily trading volume over the twelve months ended December 31, 2006 was approximately 22,000 shares. As a result, holders of our shares may have difficulty selling a large number of shares of our common stock in the manner or at a price that might otherwise be attainable if our shares were more actively traded.

The market price of our common stock could be subject to significant fluctuations. Among the factors that could affect our stock price are:

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The stock markets in general have experienced broad fluctuations that have often been unrelated to the operating performance of particular companies. These broad market fluctuations may adversely affect the trading price of our common stock.

Certain provisions of our governing documents and Oregon law could discourage potential acquisition proposals. Our articles of incorporation contain provisions that:

In addition, we are subject to the Oregon Business Combination Act, which imposes certain restrictions on business combination transactions and may encourage parties interested in acquiring us to negotiate in advance with our board of directors. We also have a shareholder rights plan that acts to discourage any person or group from making a tender offer for, or acquiring, more than 15% of our common stock without the approval of our board of directors. Any of these provisions could discourage potential acquisition proposals, could deter, delay or prevent a change in control that our shareholders consider favorable and could depress the market value of our common stock.

None.

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Properties

The following table provides certain information about our eight operating facilities as of December 31, 2006:

As of December 31, 2006, we owned all of our facilities except for one of our Saginaw, Texas facilities, which is under a long-term lease through 2008, or 2019 if all extensions are exercised. We also own a facility in Bossier City, Louisiana, which is not currently operating.

We have available manufacturing capacity from time to time at each of our facilities. To take advantage of market opportunities, we may identify capital projects that will allow us to expand our manufacturing facilities to meet expected growth opportunities. We believe the quality and productive capacity of our facilities are sufficient to maintain our competitive position for the foreseeable future.

In November 1999, the Oregon Department of Environmental Quality (“ODEQ”) requested performance of a preliminary assessment of our plant located at 12005 N. Burgard in Portland, Oregon. The purpose of the assessment is to determine whether the plant has contributed to sediment contamination in the Willamette River. We entered into a Voluntary Letter Agreement with ODEQ in mid-August 2000, and began working on the assessment. On December 1, 2000, a section of the lower Willamette River known as the Portland Harbor was included on the National Priorities List (“NPL”) at the request of the U.S. Environmental Protection Agency (“EPA”). EPA has not fully defined the stretch of the river that will make up the site. However, the full and final site will include “all suitable areas in proximity to the contamination necessary for the implementation of the response action” including upland portions of the Site that contain sources of contamination to the sediments in the river. Our plant is not located on the Willamette River; it lies in what may be the uplands portion of the Portland Harbor Site. EPA and ODEQ have agreed to share responsibility for leading the investigation and cleanup of the Portland Harbor Site. ODEQ has the lead responsibility for conducting the upland work. The actual work in both the river and uplands is being performed by various owners or operators of land and facilities within the Site.

EPA and ODEQ have notified us and 68 other parties of potential liability under the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”) and the Resource Conservation and Recovery Act (“RCRA”) with respect to the Portland Harbor Site. EPA and ODEQ have urged us and other parties receiving the letters to voluntarily enter into negotiations to participate in a remedial investigation and

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feasibility study (“RI/FS”) at the Portland Harbor Site. That RI/FS is currently being conducted by a group of potentially responsible parties known as the Lower Willamette Group (“LWG”). We, along with other parties, reached an Interim Remedial Investigation / Feasibility Study settlement in February, 2007. This agreement, if not terminated, requires us to make a payment of $175,000 on June 8, 2007 to the LWG. This is an interim settlement only and does not obligate us to any further payment or liabilities. Therefore, the extent of our participation in this work is not known, and no adjustments to our financial statements have been recorded for this matter as of December 31, 2006.

In 2001, groundwater containing elevated volatile organic compounds (VOCs) was identified in one localized area of our property furthest from the river. Assessment work in 2002 and 2003 to further characterize the groundwater is consistent with the initial conclusion that a source of the VOCs is located off site. There is no evidence at this time showing a connection between detected VOCs in groundwater and Willamette River sediments. ODEQ recommended a remedial investigation and feasibility study for further evaluation of both groundwater and stormwater at the plant. On January 25, 2005, ODEQ and we entered into a Voluntary Agreement for Remedial Investigation and Source Control Measures. We completed the additional assessment work required by the Agreement and submitted a Remedial Investigation/Source Control Evaluation Report to ODEQ on December 30, 2005. The conclusions of the report indicate that VOCs in groundwater do not present an unacceptable risk to human or ecological receptors in the Willamette River, stormwater is appropriately managed under our NPDES permit and the risk assessment screening results justify a No Further Action determination for the facility. The ODEQ review of this report is ongoing. ODEQ is expected to make its recommendations by mid-2007.

We operate under numerous governmental permits and licenses relating to air emissions, stormwater run-off, and other matters. We are not aware of any current material violations or citations relating to any of these permits or licenses. We have a policy of reducing consumption of hazardous materials in our operations by substituting non-hazardous materials when possible. Our operations are also governed by many other laws and regulations, including those relating to workplace safety and worker health, principally the Occupational Safety and Health Act and regulations thereunder which, among other requirements, establish noise and dust standards. We believe that we are in material compliance with these laws and regulations and do not believe that future compliance with such laws and regulations will have a material adverse effect on our results of operations or financial condition.

From time to time, we are involved in litigation relating to claims arising out of our operations in the normal course of its business. We maintain insurance coverage against potential claims in amounts that we believe to be adequate. Management believes that it is not presently a party to any other litigation, the outcome of which would have a material adverse effect on our business, financial condition, results of operations or cash flows.

No matters were submitted to a vote of our shareholders during the quarter ended December 31, 2006.

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PART II

Market Information

Our common stock is quoted on the Nasdaq National Market System under the symbol “NWPX.” The high and low sales prices as reported on the Nasdaq National Market System for each quarter in the years ended December 31, 2006 and 2005 were as follows.

There were 76 shareholders of record and approximately 2,500 beneficial shareholders at March 15, 2007. There were no cash dividends declared or paid in fiscal years 2006 or 2005. We do not anticipate paying cash dividends in the foreseeable future.

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Stock Performance Graph

The following graph compares the performance of our common stock to the performance of the Russell 2000 Index and a weighted composite index of certain peer companies (the “Peer Group”) selected by us. The Old Peer Group was comprised of the following companies: Ameron International Corporation, Lindsay Manufacturing Co., Valmont Industries, Inc. and Maverick Tube Corporation. Maverick Tube Corporation was acquired by Tenaris in 2006, and they are no longer included in the Old Peer Group. The New Peer Group is comprised of the following companies: Ameron International Corporation, Insituform Technologies, and Lindsay Manufacturing, Co. We created the New Peer Group because we believe that the companies included have lines of business and/or stock market capitalization more comparable to ours than companies in the Old Peer Group.

The comparisons in the chart below are provided in response to SEC disclosure requirements and, therefore, are not intended to forecast or be indicative of future performance of our common stock.

Securities Authorized For Issuance Under Equity Compensation Plans

Information with respect to equity compensation plans is included under the caption “Equity Compensation Plan Information” in our definitive proxy statement for our 2007 Annual Meeting of Shareholders and is incorporated by reference herein.

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Forward-Looking Statements

This Management’s Discussion and Analysis of Financial Condition and Results of Operations and other sections of this Report contain forward-looking statements within the meaning of the Securities Litigation Reform Act of 1995 that are based on current expectations, estimates and projections about our business, management’s beliefs, and assumptions made by management. Words such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “seeks,” “estimates,” “should,” and variations of such words and similar expressions are intended to identify such forward-looking statements. These statements are not guarantees of future performance and involve risks and uncertainties that are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed or forecasted in such forward-looking statements due to numerous factors including changes in demand for our products, product mix, bidding activity, the timing of customer orders and deliveries, the price and availability of raw materials, excess or shortage of production capacity, international trade policy and regulations and other risks discussed at Item 1A under the caption “Risk Factors” and from time to time in our other Securities and Exchange Commission filings and reports. In addition, such statements could be affected by general industry and market conditions and growth rates, and general domestic and international economic conditions. Such forward-looking statements speak only as of the date on which they are made and we do not undertake any obligation to update any forward-looking statement to reflect events or circumstances after the date of this Report. If we do update or correct one or more forward-looking statements, investors and others should not conclude that we will make additional updates or corrections with respect thereto or with respect to other forward-looking statements.

Overview

We are a leading North American manufacturer of large-diameter, high-pressure steel pipeline systems for use in water infrastructure applications, primarily related to drinking water systems. Our pipeline systems are also used for hydroelectric power systems, wastewater systems and other applications. We also make products for industrial plant piping systems and certain structural applications. These pipeline systems are produced by our Water Transmission Group from five manufacturing facilities strategically located across the United States in Portland, Oregon; Denver, Colorado; Adelanto, California; Parkersburg, West Virginia; and Saginaw, Texas. Our Water Transmission Group accounted for approximately 71% of net sales in 2006.

Our Tubular Products Group operates two manufacturing facilities in Atchison, Kansas, and Houston, Texas and produces a range of products used in several different markets. We currently make energy pipe, fire protection sprinkler pipe, agricultural pipe, traffic signpost systems and standard pipe that is sold to distributors and used in many different applications. Our Tubular Products Group generated approximately 24% of our net sales in 2006.

Our Fabricated Products Group generated the remaining 5% of our net sales in 2005. Our Fabricated Products Group primarily produces propane tanks for distribution in rural and suburban areas of the United States. These tanks range in size from 120 gallons to 1,000 gallons. All of these products are produced at our Monterrey, Mexico facility. Recently, we completed an expansion of this facility that should double its capacity. The new production lines are targeted towards manufacturing other steel or aluminum pressure vessels and fabricated parts. We have a number of projects in the prototype or trial order stages that are targeted to the energy, transportation and water industries.

Our water infrastructure products are sold generally to installation contractors, who include our products in their bids to municipal agencies or privately-owned water companies for specific projects. We believe our sales are substantially driven by spending on new water infrastructure with a recent trend towards spending on water infrastructure replacement, repair and upgrade. Within the total pipeline, our products tend to fit the larger-diameter, higher-pressure applications. We believe, because of our reputation for quality, our long relationships and our breadth of product offerings, our products are generally included in most projects for which the pipe falls within our manufacturing strengths.

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Our Tubular Products Group’s sales volume is typically driven by non-residential construction spending, energy, highway spending and general economic conditions. In 2005 we began to shift the focus of our Tubular Products Group on products for which we believe we have a sustainable advantage and to reduce our reliance on products which are very susceptible to import competition. This strategy resulted in lower volume in 2005, but in 2006 we were able to increase this group’s sales through growth in energy products.

Overall demand for our Fabricated Products Group’s propane tanks is primarily driven by weather patterns and residential heating needs, construction activity, and general economic conditions. Our new products, if they develop as expected, will be sold to OEMs in the transportation, energy and water industries.

Critical Accounting Policies

The discussion and analysis of our financial condition and results of operations are based upon our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States.

Management Estimates:

The preparation of our financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent assets and liabilities. On an on-going basis, we evaluate all of our estimates, including those related to revenue recognition, allowance for doubtful accounts, warranties, intangible assets, accrued liabilities, income taxes, and contingencies and litigation. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from these estimates under different assumptions or conditions. We believe the following critical accounting policies and related judgments and estimates affect the preparation of our consolidated financial statements.

Revenue Recognition:

Revenue from construction contracts in our water transmission segment is recognized on the percentage-of-completion method, measured by the percentage of total costs incurred to date to the estimated total costs of each contract. Estimated total costs of each contract are reviewed on a monthly basis by project management and operations personnel for all projects that are fifty percent or more complete except that major projects, usually over $5.0 million, are reviewed earlier if sufficient production has been completed to provide enough information to revise the original estimated total cost of the project. All cost revisions that result in the gross profit as a percent of sales increasing or decreasing by greater than one percent are reviewed by senior management personnel. Contract costs include all direct material and labor costs and those indirect costs related to contract performance, such as indirect labor, supplies, tools, repairs and depreciation. Selling, general and administrative costs are charged to expense as incurred. Provisions for losses on uncompleted contracts are made in the period such losses are known. Changes in job performance, job conditions and estimated profitability, including those arising from contract penalty provisions and final contract settlements may result in revisions to costs and income and are recognized in the period in which the revisions are determined. Historically, actual results have been within management’s estimates. Management has discussed the development and selection of this critical accounting estimate with the audit committee of our board of directors.

Revenue from our tubular products and fabricated products segments is recognized when all four of the following criteria have been satisfied: persuasive evidence of an arrangement exists; delivery has occurred; the price is fixed or determinable; and collectibility is reasonably assured.

Allowance for Doubtful Accounts:

We maintain allowances for estimated losses resulting from the inability of our customers to make required payments and from contract disputes. The extension and revision of credit is established by obtaining credit

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rating reports or financial information of a potential customer. Trade receivable balances are evaluated at least monthly. If it is determined that the customer will be unable to meet its financial obligation to us as a result of a bankruptcy filing, deterioration in the customer’s financial position, contract dispute, product claim or other similar events, a specific allowance is recorded to reduce the related receivable to the expected recovery amount given all information presently available. A general allowance is recorded for all other customers based on certain other factors including the length of time the receivables are past due and historical collection experience with individual customers. As of December 31, 2006, the accounts receivable balance of $68.4 million is reported net of allowances for doubtful accounts of $823,000. We believe the reported allowances at December 31, 2006, are adequate. If the customers’ financial conditions were to deteriorate resulting in their inability to make payments, additional allowances may need to be recorded, which would result in additional selling, general and administrative expenses being recorded for the period in which such determination was made. Historically, actual results have been within management’s estimates. Management has discussed the development and selection of this critical accounting estimate with the audit committee of our board of directors.

Goodwill:

Goodwill represents the excess of cost over the assigned value of the net assets in connection with all acquisitions. Goodwill is reviewed for impairment in accordance with Statement of Financial Accounting Standard (“SFAS”) No. 142 “Goodwill and Other Intangible Assets.” SFAS 142 requires that goodwill and intangible assets with indefinite lives are no longer amortized but are reviewed for impairment annually or more frequently if impairment indicators arise. We review for impairment by comparing the fair value of the reporting unit that includes goodwill, as measured by discounted cash flows, market multiples based on earnings, and other valuation methodologies, to the carrying value. As required under SFAS 142, we performed our annual assessment for impairment of the goodwill as of December 31, 2006; based on our analysis, we believe no impairment of goodwill exists.

Long-Lived Assets:

Property and equipment are reviewed for impairment in accordance with SFAS No. 144, “Accounting for the Disposal of Long-Lived Assets.” We assess impairment of property and equipment whenever changes in circumstances indicate that the carrying values of the assets may not be recoverable. The recoverable value of long-lived assets is determined by estimating future undiscounted cash flows using assumptions about our expected future operating performance. Our estimates of undiscounted cash flows may differ from actual cash flow due to, among other things, technological changes, economic conditions, or changes to our business operations. If we determine the carrying value of the property and equipment will not be recoverable, we calculate and record an impairment loss.

Effective January 1, 2006, we elected to change our accounting method related to depreciation of certain equipment from the straight-line method of depreciation to the units of production method of depreciation, which is considered a preferable method of accounting for such long-lived, nonfinancial assets. We have determined this change to be preferable under accounting principles generally accepted in the United States as it more accurately reflects the pattern of consumption of the equipment. In accordance with SFAS No. 154, “Accounting Changes and Error Corrections—a replacement of APB Opinion No. 20 and FASB Statement No. 3,” this change, accounted for as a change in estimate effected by a change in accounting principle, has been applied prospectively.

Inventories:

Inventories are stated at the lower of cost or market. Finished goods and Tubular Products and Fabricated Products raw material are stated at cost using the first-in, first-out method of accounting. Raw material inventories of steel coil are stated at cost on a specific identification. Raw material inventories of coating and lining materials, as well as materials and supplies, are stated on an average cost basis.

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Product Warranties:

Our standard terms and conditions of sale include a warranty for our products to be free of certain defects. We record a general reserve for warranty claims based on historical experience. If actual warranty claims differ from our estimates, revisions to the reserve would be necessary.

Income Taxes:

We record deferred income tax assets and liabilities based upon the difference between the financial statement and income tax bases of assets and liabilities using enacted income tax rates. Valuation allowances are established when necessary to reduce deferred income tax assets to the amount expected to be realized. Income tax expense is the tax payable for the period and the change during the period in net deferred income tax assets and liabilities.

Self Insurance:

We are self-insured for a portion of losses and liabilities associated with workers compensation claims at our West Virginia facility. Losses are accrued based upon our estimates of the aggregate liability for claims incurred using historical experience and certain actuarial assumptions followed in the insurance industry. We have purchased stop-loss coverage in order to limit, to the extent practical, the aggregate exposure to claims. There is no assurance that such coverage will adequately protect us against liability from all potential consequences.

Pension Benefits:

We have two defined benefit pension plans that are frozen. We fund these plans to cover current plan costs plus amortization of the unfunded plan liabilities. To record these obligations, management uses estimates relating to assumed inflation, investment returns, mortality, employee turnover, and discount rates. Management, along with third-party actuaries, reviews all of these assumptions on an ongoing basis.

Results of Operations

The following table sets forth, for the periods indicated, certain financial information regarding costs and expenses expressed as a percentage of total net sales and net sales of our business segments.

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Year Ended December 31, 2006 Compared to Year Ended December 31, 2005

Net sales. Net sales increased to $346.6 million in 2006 from $329.0 million in 2005. No single customer accounted for 10% or more of total net sales in 2006 or 2005.

Water Transmission sales increased 5.5% to $244.8 million in 2006 from $232.1 million in 2005. Net sales increased over the same period last year as a result of increased volume, which is attributable to stronger demand that began in the second quarter of 2006 and continued through the end of 2006. In addition to increased sales, the stronger demand resulted in a record backlog at December 31, 2006 of $198.2 million, as compared to the backlog of $125.6 million at the beginning of 2006. Bidding activity, backlog and sales resulting from the award of new projects, or the production of current projects, may vary significantly from period to period.

Tubular Products sales increased 5.1% to $84.8 million in 2006 from $80.7 million in 2005. The majority of the increase in net sales over last year resulted from improved energy product sales.

Fabricated Products sales increased 4.8% to $17.0 million in 2006 from $16.2 million in 2005. The increase in net sales was a result of increased demand for our propane tank products in the first nine months of the year, offset slightly by a drop in demand in the last quarter of 2006.

Gross profit. Gross profit increased to $56.7 million (16.4% of total net sales) in 2006 from $53.8 million (16.3% of total net sales) in 2005.

Water Transmission gross profit decreased slightly to $46.6 million (19.0% of segment net sales) in 2006 from $46.8 million (20.1% of segment net sales) in 2005. Our Water Transmission gross profit and our gross profit as a percent of segment net sales decreased as a result of product mix. Unlike 2005, where the market was strong in the first half of the year and began to soften in the second half of 2005, 2006 saw a continuation of a relatively slower market though much of the first half of 2006 and then a strengthening in the second half of 2006. Historically, during periods of slow or slowing markets, we see a much more competitive bidding environment. As a result, the projects that were booked during the later part of 2005 and through much of the first half of 2006 were at lower margins and the majority of these projects were produced in 2006.

Gross profit from Tubular Products increased 58.5% to $8.9 million (10.5% of segment net sales) in 2006 from $5.6 million (7.0% of segment net sales) in 2005. Our Tubular Products gross margin percentage increased from the same period last year primarily because of the shift from products that competed directly with imported tubing, to products that we believe have a sustainable competitive market advantage.

Fabricated Products’ gross profit decreased to $1.2 million (6.9% of segment net sales) in 2006 from $1.4 million (8.6% of segment net sales) in 2005. Fabricated Products’ gross profit decreased over the same period last year due to lower volume in the fourth quarter and the inability to pass on the higher cost of steel to our customers in 2006.

Selling, general and administrative expenses. Selling, general and administrative expenses increased 4.1% to $27.4 million (7.9% of total net sales) in 2006 from $26.3 million (8.0% of total net sales) in 2005. The majority of the increase resulted from an increase in incentive compensation and the expensing of stock options that was required beginning on January 1, 2006.

Gain on the sale of assets. On May 31, 2006, we completed the sale of our manufacturing facility in Riverside, California, included in Assets Held for Sale at December 31, 2005. A gain of $7.7 million was recorded.

Interest expense. Interest expense decreased from $7.4 million in 2005 to $6.7 million in 2006. The decrease in interest expense resulted from lower average outstanding borrowings.

Income taxes. Our effective tax rate was approximately 33.9% in 2006 and 33.4% in 2005. The effective tax rates in 2005 and 2006 were lower than historical effective rates. The decrease in our 2006 effective tax rate was

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mainly due to research and development tax credits that were recorded on amended income tax returns. The decrease in our 2005 effective tax rate was due to changes in Section 199 manufacturing deductions, changes in state apportionment factors, and the resolution of previously uncertain tax matters.

Year Ended December 31, 2005 Compared to Year Ended December 31, 2004

Net sales. Net sales increased to $329.0 million in 2005 from $291.9 million in 2004. No single customer accounted for 10% or more of total net sales in 2005 or 2004.

Water Transmission sales increased 30.6% to $232.1 million in 2005 from $177.8 million in 2004. Net sales increased over the same period in 2004 as a result of increased volume, which was attributable to stronger demand. Our Water Transmission business is impacted by infrastructure improvements; as municipal water agencies initiate improvements, we generally experience an increase in demand for our products. In addition to increased sales, the stronger demand resulted in a consistently strong backlog at December 31, 2005 of $125.6 million, as compared to the backlog of $128.9 million at the beginning of 2005.

Tubular Products sales decreased 21.3% to $80.7 million in 2005 from $102.5 million in 2004. The decrease in net sales over the same period in 2004 was expected, as the strong market conditions experienced in 2004 could not be sustained. Volume decreased in 2005 as we focused our efforts on products we believed offered the opportunity for sustainable profitability, and did not directly compete with low cost imports.

Fabricated Products sales increased 39.9% to $16.2 million in 2005 from $11.6 million in 2004. The increase in net sales was attributable to improved demand, which allowed for an increase in sales prices, and a small increase in market share.

Gross profit. Gross profit increased to $53.8 million (16.3% of total net sales) in 2005 from $49.3 million (16.9% of total net sales) in 2004.

Water Transmission gross profit increased 38.1% to $46.8 million (20.1% of segment net sales) in 2005 from $33.9 million (19.0% of segment net sales) in 2004. Our Water Transmission gross profit improved as our production continued to be strong throughout the year, and we were able to take advantage of consistent higher plant utilization.

Gross profit from Tubular Products decreased 62.4% to $5.6 million (7.0% of segment net sales) in 2005 from $15.0 million (14.6% of segment net sales) in 2004. Our Tubular Products gross margin percentage decreased from the same period in 2004 primarily because, as selling prices stabilized, our cost of goods sold increased because of high cost steel, which reduced our margin.

Fabricated Products gross profit increased to $1.4 million (8.6% of segment net sales) in 2005 from $435,000 (3.7% of segment net sales) in 2004. Fabricated Products gross profit increased over the same period in 2004 due to increased volume combined with better productivity in our operations, and higher selling prices during 2005 as compared to 2004.

Selling, general and administrative expenses. Selling, general and administrative expenses increased 13.8% to $26.3 million (8.0% of total net sales) in 2005 from $23.1 million (7.9% of total net sales) in 2004. While the increase was consistent with the increase in sales, specific factors affecting the increase in expenses included an increase in incentive compensation, and an increase in information systems costs due to our system upgrade completed in 2005.

Interest expense. Interest expense increased to $7.4 million in 2005 from $6.3 million in 2004. The increase in interest expense resulted from an increase in both our outstanding borrowings and the rates on those borrowings.

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Income taxes. Our effective tax rate was approximately 33.4% in 2005 and 37.6% in 2004. The decrease in our effective tax rate was due to changes in Section 199 manufacturing deductions, changes in state apportionment factors, and the resolution of previously uncertain tax matters.

Liquidity and Capital Resources

We generally finance our operations through cash flows from operations and available borrowings. At December 31, 2006, we had cash and cash equivalents of $4.3 million and available borrowings of $26.1 million.

Net cash provided by operating activities in 2006 was $2.0 million. This was primarily the result of our net income of $20.0 million, non-cash adjustments for depreciation and amortization of $3.8 million, an increase in accounts payable of $22.0 million, offset by non-cash adjustments for the deferred gain on sale-leaseback of equipment and a gain from the sale of property and equipment of $1.3 and $8.2 million, respectively, and an increase in inventories of $30.1 million and an increase in trade and other receivables, net of $2.5 million. The increase in inventories and accounts payable resulted primarily from an increase in steel shipments from our vendors at the end of 2006 to support the increase in the production of our Water Transmission Group.

Net cash used in investing activities in 2006 was $48.0 million, which resulted from paying off the majority of our operating leases with resultant additions of property and equipment, offset by $10.4 million in proceeds, primarily from the sale of the Riverside property and equipment in May of 2006.

Net cash provided by financing activities in 2006 was $50.2 million, which primarily resulted from proceeds of $53.6 million from a follow-on stock offering that was completed in November 2006 and option exercises, net payments of $5.3 million on our long-term debt agreements and $1.6 million net borrowings on our line of credit to a financial institution. In November of 2006 we sold 1,955,000 shares and raised $53.1 million after underwriting discounts, commissions and other expenses. The proceeds were used to payoff the operating leases mentioned above and lower our borrowings on our credit agreement.

Cash and cash equivalents increased from $133,000 as of December 31, 2005 to $4.3 million as of December 31, 2006. The increase is a result of cash receipts that had not been applied to our outstanding line of credit balance.

We had the following significant components of debt at December 31, 2006: a $65.0 million credit agreement, under which $43.0 million was outstanding, against which $4.1 million in cash receipts had not yet been applied to the outstanding balance; $8.6 million of Series B Senior Notes; $5.0 million of Senior Notes; $15.0 million of Series A Term Note, $10.5 million of Series B Term Notes, $10.0 million of Series C Term Notes, $4.5 million of Series D Term Notes and a $4.0 million Industrial Revenue Bond.

The credit agreement expires on May 20, 2010. The balance outstanding under the credit agreement bears interest at rates related to LIBOR plus 0.75% to 1.50%, or the lending institution’s prime rate, minus 0.5% to 0.0%. We had $43.0 million outstanding under the line of credit bearing interest at a weighted average rate of 6.91%, against which $4.1 million in cash receipts had not yet been applied to the outstanding balance as of December 31, 2006. At December 31, 2006 we had an additional net borrowing capacity under the line of credit of $26.1 million.

The Series A Term Note in the principal amount of $15.0 million matures on February 25, 2014 and requires annual payments in the amount of $2.1 million that begin February 25, 2008 plus interest of 8.75% paid quarterly on February 25, May 25, August 25 and November 25. The Series B Term Notes in the principal amount of $10.5 million mature on June 21, 2014 and require annual payments in the amount of $1.5 million that begin June 21, 2008 plus interest of 8.47% paid quarterly on March 21, June 21, September 21 and December 21. The Series C Term Notes in the principal amount of $10.0 million mature on October 26, 2014 and require annual payments of $1.4 million that begin October 26, 2008 plus interest of 7.36% paid quarterly on

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January 26, April 26, July 26 and October 26. The Series D Term Notes in the principal amount of $4.5 million mature on January 24, 2015 and require annual payments in the amount of $643,000 that begin January 24, 2009 plus interest of 7.32% paid quarterly on January 24, April 24, July 24, and October 24. The Series B Senior Notes in the principal amount of $8.6 million mature on April 1, 2008 and require annual payments of $4.3 million that began April 1, 2002 plus interest at 6.91% paid quarterly on January 1, April 1, July 1 and October 1. The Senior Notes in the principal amount of $5.0 million mature on November 15, 2007 and require annual payments in the amount of $5.0 million that began November 15, 2001 plus interest of 6.87% paid quarterly on February 15, May 15, August 15, and November 15. The Senior Notes and Series B Senior Notes (together, the “Notes”) also include supplemental interest from 0.0% to 1.5% (0.0% at December 31, 2006), based on our total minimum net earnings before tax plus interest expense (net of capitalized interest expense), depreciation expense and amortization expense (“EBITDA”) to total debt leverage ratio, which is paid with the required quarterly interest payments. The Industrial Revenue Bond in the principal amount of $4.0 million matures on July 1, 2016 and requires monthly principal and interest payments, at 5.22%, in the amount of $50,000 that begin February 1, 2007. The Notes, the Series A Term Note, the Series B Term Notes, the Series C Term Notes, and the Series D Term Notes (together, the “Term Notes”) and the credit agreement are collateralized by accounts receivable, inventory and certain equipment.

We lease certain equipment used in the manufacturing process. The aggregated interest rate on the capital leases is 5.2%.

The following table sets forth our commitments under the terms of our debt obligations and operating leases:

We also have entered into stand-by letters of credit that total approximately $15.0 million as of December 31, 2006. The stand-by letters of credit relate to customer owned material, workers’ compensation and general liability insurance. Due to the nature of these arrangements and our historical experience, we do not expect to make any significant payments under these arrangements. Therefore, they have been excluded from our aggregate commitments identified above.

The credit agreement, the Notes, the Term Notes and Industrial Revenue Bond all require compliance with the following financial covenants: minimum consolidated tangible net worth, maximum consolidated total debt to consolidated EBITDA ratio, a minimum consolidated fixed charge coverage ratio and a minimum asset coverage ratio. These and other covenants included in our financing agreements impose certain requirements with respect to our financial condition and results of operations, and place restrictions on, among other things, our ability to incur certain additional indebtedness, to create liens or other encumbrances on assets and capital expenditures. A failure by us to comply with the requirements of these covenants, if not waived or cured, could permit acceleration of the related indebtedness and acceleration of indebtedness under other instruments that include cross-acceleration or cross-default provisions. At December 31, 2006, we were not in violation of any of the covenants in our debt agreements.

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We expect to continue to rely on cash generated from operations and other sources of available funds to make required principal payments under the Notes during 2007. We anticipate that our existing cash and cash equivalents, cash flows expected to be generated by operations, and amounts available under our credit agreement will be adequate to fund our working capital and capital requirements for at least the next twelve months. To the extent necessary, we may also satisfy capital requirements through additional bank borrowings, senior notes, term notes and capital and operating leases, if such resources are available on satisfactory terms. We have from time to time evaluated and continue to evaluate opportunities for acquisitions and expansion. Any such transactions, if consummated, may use a portion of our working capital or necessitate additional bank borrowings.

Off Balance Sheet Arrangements

Other than non-cancelable operating lease commitments, we do not have off-balance sheet arrangements, financings, or other relationships with unconsolidated entities or other persons, also known as “special purpose entities.”

Related Party Transactions

We have ongoing business relationships with certain affiliates of Wells Fargo & Company (“Wells Fargo”). Wells Fargo, together with certain of its affiliates, owns more than ten percent of our outstanding stock. During the year ended December 31, 2006, we made payments to affiliates of Wells Fargo for operating lease payments, pursuant to which we lease certain equipment from such affiliates. During the years ended December 31, 2005 and 2004, we made the following payments to affiliates of Wells Fargo: (i) capital and operating lease payments pursuant to which the Company leases certain equipment from such affiliates, (ii) payments of interest and fees pursuant to letters of credit originated by such affiliates, (iii) payments of principal and interest on an industrial development bond, and (iv) payments of principal, interest and related fees in connection with loan agreements between the Company and such affiliates. Payments made by us to Wells Fargo and its affiliates amounted to $396,000, $3.3 million and $3.5 million for the years ended December 31, 2006, 2005 and 2004, respectively. Balances due to Wells Fargo and its affiliates were $0 at December 31, 2006 and 2005, respectively.

Recent Accounting Pronouncements

In February 2007 the Financial Accounting Standards Board (“FASB”) issued SFAS No. 159, “The Fair Value Option for Financial Assets and Financial Liabilities” (“SFAS 159”). SFAS 159 permits companies to choose to measure many financial instruments and certain other items at fair value. SFAS 159 seeks to improve the overall quality of financial reporting by providing companies the opportunity to mitigate volatility in reported earnings caused by measuring related assets and liabilities differently without having to apply complex hedge accounting provisions. SFAS 159 is effective for fiscal years beginning after November 15, 2007. We are assessing SFAS 159 and have not determined the impact that the adoption of SFAS 159 will have on our financial position or results of operations.

In September 2006, the FASB issued SFAS No. 158, “Employers’ Accounting for Defined Benefit Pension and Other Postretirement Plans—an amendment of FASB Statements No. 87, 88, 106 and 132(R)” (“SFAS 158”). SFAS 158 requires employers to recognize the overfunded or underfunded status of a defined benefit post-retirement plan as an asset or liability in its statement of financial position. Further, SFAS 158 requires employers to recognize changes in the funded status in the year in which the changes occur through comprehensive income. SFAS 158 is effective for fiscal years ending after December 15, 2006. The adoption of SFAS 158 did not have a material effect on our financial position or results of operations.

In September 2006, the SEC staff released Staff Accounting Bulletin No. 108, “Considering the Effects of Prior Year Misstatements When Quantifying Misstatements in Current Year Financial Statements” (“SAB 108”). SAB 108 was issued in order to eliminate the diversity of practice surrounding how public companies quantify

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financial statement misstatements. Traditionally, there have been two widely-recognized methods for quantifying the effects of financial statement misstatements: the “roll-over” method and the “iron curtain” method. The roll-over method focuses primarily on the impact of a misstatement on the income statement, including the reversing effect of prior year misstatements, but its use can lead to the accumulation of misstatements in the balance sheet. The iron curtain method focuses primarily on the effect of correcting the period-end balance sheet with less emphasis on the reversing effects of prior year errors on the income statement. See Note 1 to the consolidated financial statements for a discussion of the impact that the adoption of SAB 108 had on our financial position.

In September 2006, the FASB issued SFAS No. 157, “Fair Value Measurements” (“SFAS 157”). SFAS 157 defines fair value, establishes a framework for measuring fair value and requires enhanced disclosures about fair value measurements. SFAS 157 requires companies to disclose the fair value of its financial instruments according to a fair value hierarchy (i.e., levels 1, 2, and 3, as defined). Additionally, companies are required to provide enhanced disclosure regarding instruments in the level 3 category, including a reconciliation of the beginning and ending balances separately for each major category of assets and liabilities. SFAS 157 is effective for financial statements issued for fiscal years beginning after November 15, 2007 and interim periods within those fiscal years. We are assessing SFAS 157 and have not determined the impact that the adoption of SFAS 157 will have on our financial position or results of operations.

In June 2006, the FASB issued FASB Interpretation No. 48, “Accounting for Uncertainty in Income Taxes—an interpretation of FASB Statement No. 109” (“FIN 48”). FIN 48 prescribes a recognition threshold and measurement attribute for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return, and also provides guidance on derecognition, classification, interest and penalties, accounting in interim periods, disclosure, and transition. FIN 48 is effective for fiscal years beginning after December 15, 2006. We are assessing FIN 48 and have not determined the impact that the adoption of FIN 48 will have on our financial position or results of operations.

In June 2006, the FASB ratified the consensus reached by the Emerging Issues Task Force (“EITF”) related to EITF Issue No. 06-3, “How Taxes Collected from Customers and Remitted to Governmental Authorities Should Be Presented in the Income Statement (That Is, Gross versus Net Presentation)” (“EITF 06-3”). EITF 06-3 concludes that the presentation of any tax assessed by a governmental authority that is both imposed on and concurrent with a specific revenue-producing transaction between a seller and a customer, and may include, but is not limited to, sales, use, value added, and some excise taxes on either a gross basis (included in revenues and costs) or a net basis (excluded from revenues) is an accounting policy that should be disclosed. In addition, for any such taxes that are reported on a gross basis, an entity should disclose the amounts of those taxes in interim and annual financial statements for each period for which an income statement is presented if those amounts are significant. The provisions of EITF 06-3 should be applied to financial reports for interim and annual reporting periods beginning after December 15, 2006, with earlier adoption permitted. We do not believe that the adoption of EITF 06-3 will have a material impact on our financial position or results of operations.

In June 2006, the FASB ratified the consensus reached by the EITF related to EITF Issue No. 06-5 “Accounting for Purchases of Life Insurance—Determining the Amount That Could Be Realized in Accordance with FASB Technical Bulletin No. 85-4, Accounting for Purchases of Life Insurance” (“EITF 06-5”), which requires that a policyholder consider additional amounts included in the contractual terms of the policy in determining the amount that could be realized under the life insurance policy. EITF 06-5 provides additional guidance for determining the amount to be realized, including the policy level for which the analysis should be performed, amounts excluded and measurement criteria. EITF 06-5 is effective for fiscal years beginning after December 15, 2006. We are assessing EITF 06-5 and have not determined the impact that the adoption of EITF 06-5 will have on our financial position or results of operations.

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We transact business in various foreign countries, and from time to time settle our transactions in foreign currencies. We have established a program that utilizes foreign currency forward contracts to offset the risk associated with the effects of certain foreign currency exposures. These forward contracts are not used for trading or for speculative purposes. Our foreign currency exposures typically arise from sales contracts denominated in Canadian currency, for which there is exposure associated with potential foreign currency rate changes occurring between the contract date and the date when the payments are received. Under this program, increases or decreases in our foreign currency exposures are offset by gains or losses on the forward contracts, to mitigate the possibility of foreign currency transaction gains or losses. We have six Foreign Exchange Agreements (“Agreements”) at December 31, 2006, which were for an original amount of $13.0 million, of which $2.3 million was still open. Net foreign exchange transaction gains (losses) included in the accompanying consolidated statements of operations were not material for the years ended December 31, 2006 and 2005, respectively. We believe our current risk exposure to exchange rate movements to be de minimis.

We are exposed to cash flow and fair value risk due to changes in interest rates with respect to certain portions of our debt. The debt subject to changes in interest rates is our $65.0 million revolving credit line ($43.0 million outstanding as of December 31, 2006). Management believes our current risk exposure to interest rate movements to be immaterial.

Additional information required by this item is set forth in “Item 2—Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources.”

The Consolidated Financial Statements required by this item are included on pages F-1 to F-26. The financial statement schedule required by this item is included on page S-1. The quarterly information required by this item is included under the caption Quarterly Data (unaudited), in Note 16 of the Notes to Consolidated Financial Statements as listed in Item 15 of Part IV of this Report.

None.

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) that are designed to ensure that information required to be disclosed in our filings under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms, and that such information is accumulated and communicated to management, including our Chief Executive Officer (CEO) and Chief Financial Officer (CFO), as appropriate, to allow timely decisions regarding required disclosure.

We carried out an evaluation under the supervision and with the participation of our management, including the CEO and CFO, of the effectiveness of the design and operation of our disclosure controls and procedures as of December 31, 2006. Based upon this evaluation, our CEO and CFO have concluded that, because of the material weakness described below, our disclosure controls and procedures were not effective as of December 31, 2006. As a result of our identification of the material weakness described below, we performed additional analysis and other post-closing procedures to ensure that the consolidated financial statements were prepared in accordance with generally accepted accounting principles. Based on the additional analysis and other procedures conducted, management believes that the financial statements included in this report fairly present in all material respects our financial condition, results of operations and cash flows for the periods presented.

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Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) of the Exchange Act. Management has assessed the effectiveness of our internal control over financial reporting as of December 31, 2006. In making its assessment of internal control over financial reporting, management used the criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

A material weakness is a control deficiency, or combination of control deficiencies, that results in more than a remote likelihood that a material misstatement of the annual or interim financial statements will not be prevented or detected. As of December 31, 2006, we did not maintain effective controls to ensure the validity of certain capitalized costs. Specifically, we lacked effective controls over the accumulation of certain internal costs that were initially capitalized in our property, plant and equipment account during the combination of our Riverside and Adelanto facilities. This control deficiency resulted in an audit adjustment to our annual 2006 consolidated financial statements. Additionally, this control deficiency, if not remediated, could result in a misstatement to property, plant and equipment that could result in a material misstatement to the annual or interim consolidated financial statements that would not be prevented or detected. Accordingly, management has determined that this control deficiency constitutes a material weakness. Because of this material weakness, management (including our CEO and CFO) has concluded that, as of December 31, 2006, we did not maintain effective internal control over financial reporting, based on the criteria established in Internal Control—Integrated Framework issued by the COSO.

Management’s assessment of the effectiveness of our internal control over financial reporting as of December 31, 2006, has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report which is included herein.

Changes in Internal Control Over Financial Reporting

The aforementioned material weakness reported as of December 31, 2006 has resulted in a change in our internal control over financial reporting during the quarter ended December 31, 2006, that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Subsequent to December 31, 2006, in order to remediate the aforementioned material weakness, we implemented additional controls and procedures to ensure the validity of certain capitalized costs for self-constructed assets, which we believe renders the design and operation of our disclosure controls and procedures effective as of March 30, 2007, the date of this Form 10-K.

None.

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PART III

The information required by this item is included under the captions Elections of Directors, Executive Officers and Section 16(a) Beneficial Ownership Reporting Compliance in Northwest Pipe’s Proxy Statement for its 2006 Annual Meeting of Shareholders and is incorporated herein by reference. Management has adopted a Code of Ethics that applies to our Chief Executive Officer, Chief Financial Officer, Corporate Controller and Operations Controller. A copy of the Code of Ethics can be found on our website at www.nwpipe.com. None of the material on our website is part of this Form 10-K. If there is any waiver from any provision from the code of ethics for our Executive Officers, we will disclose the nature of such waiver on our website or in a current report on Form 8-K.

The information required by this item is included under the captions Executive Compensation and Compensation Discussion and Analysis in Northwest Pipe’s Proxy Statement for its 2007 Annual Meeting of Shareholders and is incorporated herein by reference.

The information required by this item is included under the caption Stock Owned by Management and Principal Shareholders in Northwest Pipe’s Proxy Statement for its 2007 Annual Meeting of Shareholders and is incorporated herein by reference. Information with respect to equity compensation plans is included under the caption Equity Compensation Plan Information in Northwest Pipe’s Proxy Statement for its 2007 Annual Meeting of Shareholders and is incorporated herein by reference.

The information required by this item is included under the captions Certain Relationships and Related Transactions and Election of Directors in Northwest Pipe’s Proxy Statement for its 2007 Annual Meeting of Shareholders and is incorporated herein by reference.

The information required by this item is included under the caption Independent Registered Public Accounting Firm in Northwest Pipe’s Proxy Statement for its 2007 Annual Meeting of Shareholders and is incorporated herein by reference.

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PART IV

(a) (1) Financial Statements

The Financial Statements, together with the report thereon of PricewaterhouseCoopers LLP are included on the pages indicated below.

(a) (2) Financial Statement Schedule

The following schedule is filed herewith:

Schedules not listed above have been omitted because the information required to be set forth therein is not applicable or is included in the Consolidated Financial Statements or notes thereto.

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(a) (3) Exhibits included herein:

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Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of Northwest Pipe Company:

We have completed integrated audits of Northwest Pipe Company’s consolidated financial statements and of its internal control over financial reporting as of December 31, 2006 in accordance with the standards of the Public Company Accounting Oversight Board (United States). Our opinions, based on our audits, are presented below.

Consolidated financial statements and financial statement schedule

In our opinion, the consolidated financial statements listed in the accompanying index present fairly, in all material respects, the financial position of Northwest Pipe Company and its subsidiaries at December 31, 2006 and 2005, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2006 in conformity with accounting principles generally accepted in the United States of America. In addition, in our opinion, the financial statement schedule listed in the accompanying index presents fairly, in all material respects, the information set forth therein when read in conjunction with the related consolidated financial statements. These financial statements and financial statement schedule are the responsibility of the Company’s management. Our responsibility is to express an opinion on these financial statements and financial statement schedule based on our audits. We conducted our audits of these statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit of financial statements includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

As discussed in Note 1 to the consolidated financial statements, the Company changed the manner in which it accounts for stock-based compensation in 2006.

Internal control over financial reporting

Also, we have audited management’s assessment, included in Management’s Report on Internal Control Over Financial Reporting appearing under Item 9A, that Northwest Pipe Company did not maintain effective internal control over financial reporting as of December 31, 2006, because of the effect of not maintaining effective controls to ensure the validity of certain capitalized costs, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting. Our responsibility is to express opinions on management’s assessment and on the effectiveness of the Company’s internal control over financial reporting based on our audit.

We conducted our audit of internal control over financial reporting in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. An audit of internal control over financial reporting includes obtaining an understanding of internal control over financial reporting, evaluating management’s assessment, testing and evaluating the design and operating effectiveness of internal control, and performing such other procedures as we consider necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinions.

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting

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includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

A material weakness is a control deficiency, or combination of control deficiencies, that results in more than a remote likelihood that a material misstatement of the annual or interim financial statements will not be prevented or detected. The following material weakness has been identified and included in management’s assessment. The Company did not maintain effective controls to ensure the validity of certain capitalized costs. Specifically, the Company lacked effective controls over the accumulation of certain internal costs that were initially capitalized in their property, plant and equipment account during the combination of the Riverside and Adelanto facilities. This control deficiency resulted in an audit adjustment to the annual 2006 consolidated financial statements. Additionally, this control deficiency could result in a misstatement to property, plant and equipment that could result in a material misstatement to the annual or interim consolidated financial statements that would not be prevented or detected. Accordingly, management has determined that this control deficiency constitutes a material weakness. This material weakness was considered in determining the nature, timing, and extent of audit tests applied in our audit of the December 31, 2006 consolidated financial statements, and our opinion regarding the effectiveness of the Company’s internal control over financial reporting does not affect our opinion on those consolidated financial statements.

In our opinion, management’s assessment that Northwest Pipe Company did not maintain effective internal control over financial reporting as of December 31, 2006, is fairly stated, in all material respects, based on criteria established in Internal Control—Integrated Framework issued by the COSO. Also, in our opinion, because of the effect of the material weakness described above on the achievement of the objectives of the control criteria, Northwest Pipe Company has not maintained effective internal control over financial reporting as of December 31, 2006 based on criteria established in Internal Control—Integrated Framework issued by the COSO.

/s/ PricewaterhouseCoopers LLP

Portland, Oregon

March 30, 2007

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NORTHWEST PIPE COMPANY AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF INCOME

(In thousands, except per share amounts)

NORTHWEST PIPE COMPANY AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(In thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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NORTHWEST PIPE COMPANY AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

(Dollar amounts in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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NORTHWEST PIPE COMPANY AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(Dollar amounts in thousands)

The accompanying notes are an integral part of these consolidated financial statements.

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NORTHWEST PIPE COMPANY AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Dollar amounts in thousands)