Registration No. 333-223611

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT No. 1

TO

FORM S-4

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

GRANITE CONSTRUCTION INCORPORATED

(Exact name of registrant as specified in its charter)

585 West Beach Street

Watsonville, California 95076

(831) 724-1011

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant’s Principal Executive Offices)

Richard Watts

Senior Vice President, General Counsel and Secretary

Granite Construction Incorporated

585 West Beach Street

Watsonville, California 95076

(831) 724-1011

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)

Copies to:

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable on or after the effective date of this registration statement after all other conditions to the merger described herein have been satisfied or waived.

If the securities being registered on this Form are to be offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box.    ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.    ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)    ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)    ☐

The Registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to Section 8(a), may determine.

The information contained in this proxy statement/prospectus is subject to completion or amendment. A registration statement relating to these securities has been filed with the Securities and Exchange Commission. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This proxy statement/prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities, nor shall there be any sale of these securities, in any jurisdiction in which such offer, solicitation or sale is not permitted or would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

SUBJECT TO COMPLETION, DATED APRIL 16, 2018

                , 2018

PROPOSED MERGER—YOUR VOTE IS VERY IMPORTANT

Dear Layne Stockholders:

You are cordially invited to attend a special meeting of the stockholders of Layne Christensen Company, a Delaware corporation (“Layne”), which will be held at                 (Central Time), on                 , 2018 at                 , located at                  (the “Special Meeting”).

Layne, Granite Construction Incorporated, a Delaware corporation (“Granite”), and Lowercase Merger Sub Incorporated (“Merger Sub”), a Delaware corporation and a wholly owned subsidiary of Granite, have entered into an Agreement and Plan of Merger, dated as of February 13, 2018 (the “Merger Agreement”), pursuant to which, among other things, Merger Sub will be merged with and into Layne, with Layne surviving the merger as a wholly owned subsidiary of Granite (the “Merger”). The board of directors of each of Granite and Layne has unanimously approved the Merger.

If the Merger is completed, at the effective time of the Merger (the “Effective Time”), each share of common stock, par value $0.01 per share, of Layne (“Layne Common Stock”) that is issued and outstanding will be cancelled and automatically converted into the right to receive 0.27 shares of common stock, par value $0.01 per share, of Granite (“Granite Common Stock”).

Upon completion of the Merger, former Layne stockholders will own about 5,435,720 shares, or approximately 12% of the outstanding shares, of Granite Common Stock on a fully diluted basis (excluding any shares that may subsequently be issued in connection with any conversion of the 8.0% Convertible Notes into shares of Granite Common Stock following the Merger). No fractional shares will be issued in the Merger. Layne’s stockholders will receive cash in lieu of any fractional shares.

At the Special Meeting, Layne stockholders will be asked to adopt the Merger Agreement, and approve other related proposals. Information about the Special Meeting, the Merger and other related business to be considered by Layne stockholders at the Special Meeting is included in this proxy statement/prospectus. We urge all Layne stockholders to read this proxy statement/prospectus, including the annexes, and the Layne and Granite filings incorporated by reference into this proxy statement/prospectus carefully and in their entirety. In particular, we urge you to read carefully the Risk Factors beginning on page 22.

Your vote is very important regardless of the number of shares of Layne Common Stock that you own. The Merger cannot be completed without the adoption of the Merger Agreement by the affirmative vote of a majority of the outstanding shares of Layne Common Stock entitled to vote at the Special Meeting. Whether or not you plan to attend the Special Meeting, please vote as soon as possible by following the instructions in this proxy statement/prospectus to make sure that your shares are represented at the Special Meeting. Your failure to vote your shares of Layne Common Stock at the Special Meeting will have the same effect as a vote against the proposal to adopt the Merger Agreement. The Board of Directors of Layne unanimously recommends that you vote “FOR” the adoption of the Merger Agreement and “FOR” the other proposals described in this proxy statement/prospectus.

Shares of Layne Common Stock are listed on the Nasdaq Global Select Market under the symbol “LAYN.” Shares of Granite Common Stock are listed on the New York Stock Exchange under the symbol “GVA.” We urge you to obtain current market quotations for shares of Layne Common Stock and Granite Common Stock.

We appreciate your continued support and interest in Layne.

Sincerely yours,

Michael J. Caliel

President and Chief Executive Officer

Layne Christensen Company

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the Merger or the other transactions described in this proxy statement/prospectus or the securities to be issued in connection with the Merger or determined if this proxy statement/prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

This proxy statement/prospectus is dated                 , 2018 and is expected to be first mailed to Layne stockholders on or about                 , 2018.

Layne Christensen Company

1800 Hughes Landing Blvd., Ste. 800

The Woodlands, Texas 77380

Notice of Special Meeting of Stockholders

To be Held on                 , 2018

To the Stockholders of Layne Christensen Company:

Notice is hereby given that a special meeting of stockholders of Layne Christensen Company (“Layne”) will be held on                 , 2018 at                  (Central Time), at                  (the “Special Meeting”), for the following purposes:

Approval of the proposal to adopt the Merger Agreement is required for completion of the Merger. Neither the compensation proposal nor the adjournment proposal is a condition to the obligations of Layne or Granite to complete the Merger.

Layne will transact no other business at the Special Meeting except for the proposals set forth above or such other business as may properly be brought before the Special Meeting or any adjournment or postponement thereof. Please refer to this proxy statement/prospectus, which also includes a copy of the Merger Agreement as Annex A, for further information with respect to the business to be transacted at the Special Meeting.

The Board of Directors of Layne has set                 , 2018 as the record date (the “Record Date”) for the Special Meeting. Only Layne stockholders of record at the close of business on the Record Date may vote at the Special Meeting and any adjournments thereof. A list of Layne stockholders entitled to vote at the Special Meeting will be available for inspection at Layne’s offices in The Woodlands, Texas for any purpose relevant to the Special Meeting during normal business hours for a period of ten days before the Special Meeting and at the Special Meeting. We urge you to read carefully this proxy statement/prospectus in its entirety, including the Annexes and the documents incorporated by reference herein.

The approval of the proposal to adopt the Merger Agreement requires the affirmative vote of the holders of a majority of the outstanding shares of Layne Common Stock entitled to vote at the Special Meeting. The compensation proposal and the adjournment proposal each require the affirmative vote of a majority of the votes cast “FOR” or “AGAINST” by the Layne stockholders present in person or represented by proxy at the Special Meeting and entitled to vote on such proposal, although the compensation proposal vote will not be binding on Layne. Abstentions will have the same effect as a vote against the proposal to adopt the Merger Agreement. Abstentions will have no effect on the adjournment proposal and compensation proposal. The Board of

Directors of Layne has unanimously approved the Merger Agreement and the transactions contemplated thereby and recommends that you vote “FOR” each of these proposals.

By Order of the Board of Directors,

Steven F. Crooke

Senior Vice President – Chief Administrative Officer,

General Counsel and Secretary

                , 2018

The Woodlands, Texas

PLEASE FOLLOW THE INSTRUCTIONS ON THE ENCLOSED PROXY CARD AND SUBMIT YOUR PROXY PROMPTLY. IF YOU HAVE QUESTIONS ABOUT THE PROPOSALS OR ABOUT SUBMITTING A PROXY FOR YOUR SHARES OF LAYNE COMMON STOCK, YOU SHOULD CONTACT ALLIANCE ADVISORS LLC, LAYNE’S PROXY SOLICITOR. STOCKHOLDERS PLEASE CALL TOLL-FREE AT (833) 795-8493 (BANKS AND BROKERS PLEASE CALL COLLECT AT (973) 873-7700.

ABOUT THIS PROXY STATEMENT/PROSPECTUS

Granite Construction Incorporated (“Granite”) has supplied all information contained in or incorporated by reference into this proxy statement/prospectus relating to Granite. Layne Christensen Company (“Layne”) has supplied all information contained in or incorporated by reference into this proxy statement/prospectus relating to Layne. Granite and Layne have both contributed to information relating to the Merger.

You should rely only on the information contained in or incorporated by reference into this proxy statement/prospectus. No one has been authorized to provide you with information that is different from that contained in or incorporated by reference into this proxy statement/prospectus. This proxy statement/prospectus is dated                 , 2018, and is based on information as of that date or such other date as may be noted. You should not assume that the information contained in this proxy statement/prospectus is accurate as of any other date. You should not assume that the information contained in any document incorporated or deemed to be incorporated by reference herein is accurate as of any date other than the date of such document. Any statement contained in a document incorporated or deemed to be incorporated by reference into this proxy statement/prospectus will be deemed to be modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference into this proxy statement/prospectus modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this proxy statement/prospectus. Neither the mailing of this proxy statement/prospectus to the stockholders of Layne nor the taking of any actions contemplated hereby by Granite or Layne at any time will create any implication to the contrary.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

Unless otherwise indicated or as the context otherwise requires, all references in this proxy statement/prospectus to:

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(ii)

(iii)

(iv)

REFERENCES TO ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates by reference important business and financial information about each of Granite and Layne from documents that each company has filed or will file with the SEC but that are not being included in or delivered with this proxy statement/prospectus. This information is available to you without charge upon your written or oral request. You may read and copy the documents incorporated by reference in this proxy statement/prospectus and other information about each of Granite and Layne that is filed with the SEC under the Exchange Act at the SEC’s Public Reference Room at 100 F Street, N.E., Washington, DC 20549. You can also obtain such documents free of charge through the SEC’s website, www.sec.gov, or by requesting them in writing or by telephone from the appropriate company at the following addresses and telephone numbers:

If you would like to request any documents, please do so by                 , 2018 in order to receive them before the Special Meeting.

For additional information on documents incorporated by reference in this proxy statement/prospectus, see “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus. Please note that information contained on the websites of Granite or Layne is not incorporated by reference in, or considered to be part of, this proxy statement/prospectus.

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TABLE OF CONTENTS

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QUESTIONS AND ANSWERS

The questions and answers below highlight only selected information from this proxy statement/prospectus and are intended to briefly address some commonly asked questions about, among other things, the Special Meeting, the Merger Agreement and the Merger. The Layne Board is soliciting proxies from its stockholders to vote at the Special Meeting, to be held at                  (Central Time), on                 , 2018 at                 , located at                 , and any adjournment or postponement of the Special Meeting.

These questions and answers do not contain all of the information that may be important to you. You should carefully read this entire proxy statement/prospectus and the additional documents incorporated by reference into this proxy statement/prospectus to fully understand the matters to be acted upon and the voting procedures for the Special Meeting. You may obtain the information incorporated by reference into this proxy statement/prospectus without charge by following the instructions under “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

Your vote is important. In order to complete the Merger, Layne stockholders must vote to adopt the Merger Agreement. Adoption of the Merger Agreement requires the affirmative vote of the holders of a majority of the issued and outstanding shares of Layne Common Stock entitled to vote on this proposal.

This proxy statement/prospectus is being delivered to you as both a proxy statement of Layne and a prospectus of Granite. It is a proxy statement because the Layne Board is soliciting proxies from Layne stockholders to vote on the adoption of the Merger Agreement at the Special Meeting as well as the other matters set forth in the notice of the Special Meeting and described in this proxy statement/prospectus, and your proxy will be used at the Special Meeting or at any adjournment or postponement of the Special Meeting. It is a prospectus because Granite will issue Granite Common Stock to Layne stockholders in the Merger. On or about                  , 2018, Layne intends to begin to deliver to its stockholders of record as of the close of business on the Record Date printed copies of these materials.

The adoption by Layne stockholders of the Merger Agreement is a condition to the consummation of the Merger. Neither the approval of the compensation proposal nor the approval of the Layne adjournment proposal is a condition to the Merger.

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You will own shares of Granite Common Stock and will no longer own shares in Layne following the Merger. See “The Merger Agreement” beginning on page 104 of this proxy statement/prospectus.

As of                 , 2018, the Record Date for determining stockholders of Layne entitled to vote at the Special Meeting, there were                  shares of Layne Common Stock outstanding and entitled to vote at the Special Meeting, held by approximately                  holders of record.

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Proposal 2—Approval, on an Advisory Basis, of Certain Compensatory Arrangements with Layne Named Executive Officers. Approval of the compensation proposal requires the approval of a majority of the votes cast “FOR” or “AGAINST” by the Layne stockholders present in person or represented by proxy at the Special Meeting and entitled to vote thereon. Abstentions and failures to vote will have no effect on the compensation proposal.

Proposal 3—Adjournments of the Special Meeting. Approval of the adjournment proposal requires the approval of a majority of the votes cast “FOR” or “AGAINST” by the Layne stockholders present in person or represented by proxy at the Special Meeting and entitled to vote thereon. Abstentions and failures to vote will have no effect on the adjournment proposal.

The Layne Board unanimously recommends that Layne stockholders vote “FOR” the proposal to adopt the Merger Agreement, “FOR” the compensation proposal and “FOR” the adjournment proposal.

In connection with the execution of the Merger Agreement, certain of Layne’s stockholders (including all of Layne’s directors and named executive officers) entered into voting agreements with Granite, pursuant to which they agreed to vote, and granted Granite an irrevocable proxy to vote, their shares of Layne Common Stock in favor of the proposals to be considered at the Special Meeting, including the proposal to adopt the Merger Agreement. As of the Record Date, these stockholders collectively beneficially owned approximately                 % of the outstanding shares of Layne Common Stock entitled to vote at the Special Meeting. If the Merger Agreement is terminated in accordance with its terms, these voting agreements will also terminate. A form of the voting agreements is attached hereto as Annex B. See “The Voting Agreements” beginning on page 128 of this proxy statement/prospectus.

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Please note that use of cameras, recording devices and other electronic devices will not be permitted at the Special Meeting.

Regardless of whether you intend to attend the Special Meeting, you are encouraged to vote your shares of Layne Common Stock as promptly as possible. Voting your shares will not impact your ability to attend the Special Meeting.

Voting by Telephone or over the Internet. To vote by telephone or over the Internet, please follow the instructions included on your proxy card. If you vote by telephone or over the Internet, you do not need to complete and mail a proxy card.

Voting by Mail. By signing the proxy card and returning it in the enclosed prepaid and addressed envelope, you are authorizing the individuals named on the proxy card to vote your shares at the Special Meeting in the manner you indicate. If you receive more than one proxy card, it is an indication that your shares are held in multiple accounts. Please sign and return all proxy cards to ensure that all of your shares are voted.

We encourage you to vote by telephone, over the Internet or to sign and return the proxy card even if you plan to attend the Special Meeting so that your shares will be voted if you are unable to attend the Special Meeting.

Voting in Person at the Meeting. If your shares are registered directly in your name, you are considered the stockholder of record and you have the right to vote in person at the Special Meeting. If you attend the Special Meeting and plan to vote in person, we will provide you with a ballot at the Special Meeting.

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If you are a Layne stockholder of record, you may revoke your proxy at any time before it is voted at the Special Meeting. To revoke your proxy, you must:

If you are the beneficial owner of shares held in “street name” by a brokerage firm, bank or other nominee, you should follow the instructions of your bank, broker or other nominee regarding the revocation of proxies.

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As more fully described in this proxy statement/prospectus and in the Merger Agreement, the completion of the Merger depends on a number of conditions being satisfied or, where legally permissible, waived. These conditions include, among others, (a) the adoption of the Merger Agreement by the holders of a majority of Layne Common Stock entitled to vote on such matter, (b) the expiration or termination of the applicable waiting period under the HSR Act, (c) the effectiveness of the registration statement (of which this proxy statement/prospectus is a part) relating to the issuance of the shares of Granite Common Stock to be issued in the Merger, (d) the approval for listing by NYSE, subject to notice of issuance, of the shares of Granite Common Stock to be issued in the Merger and (e) the absence of any law or regulation that prohibits the completion of the Merger. Each party’s obligation to complete the Merger is also subject to the material accuracy of the representations and warranties of the other party in the Merger Agreement and the compliance in all material respects with covenants of the other party in the Merger Agreement and (e) the absence of a material adverse effect (as described in “The Merger Agreement—Conditions to the Merger” beginning on page 106 of this proxy statement/prospectus) on the other party. The Merger Agreement does not include a financing condition.

Assuming the Merger qualifies for the Intended Tax Treatment, U.S. Holders (as defined in “Material U.S. Federal Income Tax Consequences” beginning on page 130 of this proxy statement/prospectus) will not recognize any gain or loss upon the receipt of shares of Granite Common Stock in the Merger, except with respect to cash received in lieu of fractional shares of Granite Common Stock.

Each U.S. holder of Layne Common Stock should read the discussion under “Material U.S. Federal Income Tax Consequences” and should consult its own tax advisor for a full understanding of the tax consequences of the Merger to such stockholder.

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Alliance Advisors LLC

200 Broadacres Drive, 3rd Floor

Bloomfield, New Jersey 07003

Stockholders May Call Toll-Free: (833) 795-8493

Banks and Brokers May Call Collect: (973) 873-7700

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RISK FACTORS

In addition to the other information included in and incorporated by reference into this proxy statement/prospectus, you should carefully read and consider the following risk factors in evaluating the proposals to be voted on at the Special Meeting and in determining whether to vote for adoption of the Merger Agreement. If the Merger Agreement is adopted by Layne stockholders and all of the other conditions to the Merger are satisfied or waived, and the Merger is consummated, holders of Layne Common Stock will become holders of Granite Common Stock and will be subject to the risks and uncertainties of holders thereof. Please also refer to the additional risk factors of each of Granite and Layne identified in the periodic reports and other documents incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

Risks Related to the Merger

Because the market price of Granite Common Stock will fluctuate, Layne’s stockholders cannot be certain of the value of the Merger Consideration that they will be entitled to receive in the Merger.

Upon consummation of the Merger, each share of Layne Common Stock then issued and outstanding will be cancelled and automatically converted into the right to receive 0.27 shares of Granite Common Stock. Granite will not issue any fractional shares of Granite Common Stock in the Merger. Holders of Layne Common Stock who would otherwise be entitled to a fractional share of Granite Common Stock will receive a cash payment in lieu of any fractional share. See “Unaudited Comparative Per Share Data” and “Comparative Market Value of Common Stock and Dividend Information” beginning on pages 48 and 49, respectively.

The Merger Agreement does not provide for any termination right by either Granite or Layne solely based on changes in the price or trading volume of Granite Common Stock or Layne Common Stock. Fluctuations in the market price of Granite Common Stock could result from changes in the business, operations or prospects of Layne or Granite prior to consummation of the Merger or the combined company following the completion of the Merger, regulatory considerations, general market and economic conditions and other factors both within and beyond the control of Layne or Granite.

The issuance of Granite Common Stock in connection with the Merger could decrease the market price of Granite Common Stock.

Upon consummation of the Merger, Granite expects to issue approximately 5.4 million shares of Granite Common Stock, or approximately 12% of the number of shares of Granite Common Stock outstanding as of February 13, 2018, the last trading day prior to the public announcement of the Merger Agreement, to Layne stockholders in the Merger. This does not include any shares of Granite Common Stock that may become issuable upon conversion of the 8.0% Convertible Notes. The issuance of Granite Common Stock in the Merger may result in fluctuations in the market price of Granite Common Stock, including a stock price decline.

The shares of Granite Common Stock to be received by Layne stockholders as a result of the Merger will have different rights from the shares of Layne Common Stock.

Upon consummation of the Merger, Layne stockholders will become Granite stockholders, and their rights as stockholders will be governed by the Granite Charter and the Granite Bylaws. Certain of the rights associated with Granite Common Stock are different from, and may be viewed as less favorable than, the rights associated with Layne Common Stock. See “Comparison of Rights of Holders of Granite Common Stock and Layne Common Stock” beginning on page 133 of this proxy statement/prospectus for a discussion of the different rights associated with Granite Common Stock.

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Granite and Layne may be unable to satisfy the conditions to the Merger and the Merger may not be consummated.

Consummation of the Merger is subject to various closing conditions, including, among other things, (a) the adoption of the Merger Agreement by Layne’s stockholders, (b) the expiration or termination of the applicable waiting period under the HSR Act, (c) the receipt of an opinion of counsel by both Granite and Layne, dated as of the closing, to the effect that the Merger will qualify for U.S. federal income tax purposes as a “reorganization” within the meaning of Section 368(a) of the Code and (d) the absence of any legal restraints or prohibitions on the consummation of the Merger. The obligation of each party to consummate the Merger is also conditioned upon the other party’s representations and warranties being true and correct (subject to certain materiality exceptions), the other party having performed in all material respects its obligations under the Merger Agreement and the other party not having suffered a material adverse effect (as described in “The Merger Agreement—Conditions to the Merger” beginning on page 106 of this proxy statement/prospectus).

These and other conditions to consummation of the Merger may fail to be satisfied. In addition, satisfying the conditions to the Merger may take longer, and could cost more, than Layne and Granite expect. For a more complete summary of the conditions that must be satisfied or waived prior to consummation of the Merger, see “The Merger Agreement—Conditions to the Merger” beginning on page 106 of this proxy statement/prospectus. The satisfaction of all of the required conditions could delay the completion of the Merger for a significant period of time or prevent it from occurring. Any delay in completing the Merger could cause Granite not to realize some or all of the benefits that Granite expects to achieve if the Merger is successfully consummated within its expected timeframe. Further, there can be no assurance that the conditions to the Merger will be satisfied or waived or that the Merger will be consummated. See “—Failure to complete the Merger could negatively impact the stock price and the future business and financial results of Granite and Layne.”

Layne must obtain approval of its stockholders to consummate the Merger, which, if delayed or not obtained, may jeopardize or delay the consummation of the Merger.

The Merger is conditioned on the adoption of the Merger Agreement by the affirmative vote of the holders of a majority of the issued and outstanding shares of Layne Common Stock entitled to vote thereon. If Layne stockholders do not adopt the Merger Agreement, then Layne and Granite cannot consummate the Merger.

Regulatory approvals that are required to consummate the Merger may not be received, may take longer than expected or may impose conditions that are not presently anticipated.

Under the provisions of the HSR Act, the Merger may not be consummated until notification and report forms have been filed with the Antitrust Division of the DOJ and the FTC and the expiration of a 30 calendar day waiting period (unless the waiting period is set to expire on a weekend or federal holiday, in which case the waiting period is automatically extended until 11:59 p.m. of the next business day), or the early termination of that waiting period, following the parties’ filing of their respective notification and report forms. On February 28, 2018, Layne and Granite filed their respective notification and report forms under the HSR Act with the Antitrust Division of the DOJ and the FTC. Although the FTC granted early termination of the waiting period under the HSR Act on March 12, 2018, parties who may be adversely affected by the Merger may bring legal actions under the antitrust laws in certain circumstances.

In addition, private parties who may be adversely affected by the Merger and individual states may bring legal actions under the antitrust laws in certain circumstances. Although the parties believe the completion of the Merger will not likely be prevented by antitrust law, there can be no assurance that a challenge to the Merger on antitrust grounds will not be made or, if a challenge is made, what the result will be. Under the Merger Agreement, Layne and Granite have agreed to use their reasonable best efforts to obtain all regulatory clearances necessary to complete the Merger as promptly as reasonably practicable. In addition, in order to complete the Merger, Granite and Layne may be required to comply with conditions, terms, obligations or restrictions imposed

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by regulatory entities and such conditions, terms, obligations or restrictions may have the effect of delaying completion of the Merger, imposing additional material costs on or materially limiting the revenues of Granite after the completion of the Merger, or otherwise reducing the anticipated benefits to Granite of the Merger. In addition, such conditions, terms, obligations or restrictions may result in the delay or abandonment of the Merger.

The announcement and pendency of the Merger could have an adverse effect on Layne’s stock price, business, financial condition, results of operations or business prospects.

The announcement and pendency of the Merger could disrupt Layne’s business in the following ways, among others:

Any of these matters could adversely affect the stock price, business, financial condition, results of operations or business prospects of Layne.

Failure to consummate the Merger could negatively impact the stock price and the future business and financial results of Granite and Layne.

If the Merger is not consummated for any reason, including as a result of Layne stockholders failing to adopt the Merger Agreement, the ongoing businesses of Granite and Layne may be adversely affected and, without realizing any of the benefits of having completed the Merger, Granite and Layne would be subject to a number of additional risks and consequences, including the following:

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In addition to the above risks, Layne may be required, under certain circumstances, to pay to Granite the termination fee, which may materially adversely affect Layne’s financial results. Further, Granite and Layne could be subject to litigation related to any failure to complete the Merger or related to any enforcement proceeding commenced against Granite or Layne to perform their respective obligations under the Merger Agreement. If the Merger is not completed, these risks may materialize and may adversely affect Granite’s and Layne’s businesses, financial condition, financial results and stock prices.

Granite’s and Layne’s business relationships may be subject to disruption due to uncertainty associated with the Merger.

Parties with which Granite or Layne do business may experience uncertainty associated with the proposed Merger, including with respect to current or future business relationships with Granite, Layne or the combined company. Granite’s and Layne’s business relationships may be subject to disruption as customers, distributors, suppliers, vendors and others may attempt to negotiate changes in existing business relationships or consider entering into business relationships with parties other than Granite, Layne or the combined company. These disruptions could have an adverse effect on the businesses, financial condition, or results of operations of the combined company, including an adverse effect on Granite’s ability to realize the anticipated benefits of the Merger. The risk, and adverse effect, of such disruptions could be exacerbated by a delay in consummating the Merger or termination of the Merger Agreement.

Any delay in consummating the Merger may substantially reduce the benefits that Granite expects to obtain from the Merger.

Satisfying the conditions to, and consummation of, the Merger may take longer than, and could cost more than, Granite and Layne expect. Granite and Layne cannot predict whether or when the conditions to the Merger will be satisfied, and satisfying the conditions to the Merger could delay the Effective Time for a significant period of time or prevent it from occurring. Any delay in consummating the Merger or any additional conditions imposed in order to consummate the Merger may materially adversely affect the synergies and other benefits that Granite expects to achieve if the Merger and the integration of the companies’ respective businesses are completed within the expected timeframe. In addition, each of Granite and Layne may terminate the Merger Agreement if the Merger is not consummated by September 30, 2018.

Granite may be unable to realize anticipated cost synergies or may incur additional costs.

Granite has identified approximately $20 million in pre-tax cost synergies which are expected to be realized by the third year following consummation of the Merger. Granite expects that these will result from, among other things, combining the organizational structures, locations and operations of the two companies. To realize these synergies, Granite expects to incur costs of approximately $7 million in 2018, $1 million in 2019, and $3 million in 2020. While Granite’s management believes that these cost synergies are achievable, Granite may be unable to realize all of these cost synergies within the time frame expected or at all. In addition, Granite may incur additional and/or unexpected costs in order to realize these cost synergies.

The integration of Layne may present significant challenges to Granite, and although Granite expects the Merger with Layne will result in cost savings, synergies and other benefits to Granite, Granite may not realize those benefits because of difficulties related to integration, the realization of synergies, and other challenges.

Granite and Layne have operated and, until consummation of the Merger, will continue to operate, independently, and there can be no assurances that their businesses can be integrated successfully. It is possible

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that the integration process could result in the loss of key Granite or Layne employees, the loss of customers, the disruption of either company’s or both companies’ ongoing businesses or other unexpected integration issues, higher than expected integration costs and an overall post-completion integration process that takes longer than originally anticipated. Specifically, the following issues and potential risks, among others, must be addressed in integrating the operations of Layne and Granite in order to realize the anticipated benefits of the Merger so the combined company performs as expected:

If Granite cannot successfully integrate Layne, Granite may experience material negative consequences to its business, financial condition or results of operations. Successful integration of Layne will depend on Granite’s ability to manage these operations, to realize opportunities for revenue growth and, to some degree, to eliminate redundant and excess costs. Because of difficulties in combining the two companies, Granite may not be able to achieve the benefits that it hopes to achieve as a result of the Merger.

The Merger may be consummated on different terms from those contained in the Merger Agreement.

Prior to the consummation of the Merger, the parties may, by their mutual agreement, amend or alter the terms of the Merger Agreement, including with respect to, among other things, the Merger Consideration to be received by Layne stockholders, or any covenants or agreements with respect to the parties’ respective operations

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during the pendency thereof, provided, however, that after approval by Layne stockholders, no amendment may be made without further stockholder approval which, by law or in accordance with the rules of Nasdaq, requires further approval by such stockholders. Any such amendments or alterations may have negative consequences to Layne stockholders including, among other things, reducing the cash available for Granite’s or Layne’s operations or to meet respective obligations or restricting or limiting assets or operations of either of Granite or Layne. Under certain circumstances, Layne stockholders may be permitted or required to adopt any such amendments, which could delay consummation of the Merger and subject Layne and Granite to additional expense.

Granite and Layne will incur significant transaction fees and Merger-related costs in connection with the Merger.

Granite and Layne expect to incur a number of non-recurring fees and Merger-related costs associated with combining the operations of the two companies. Most of these non-recurring costs will be comprised of transaction and regulatory costs related to the Merger, including fees paid to financial and legal advisors related to the Merger, bank fees and related financing costs and employment-related costs, including change-in-control related payments made to certain Layne executives, further described in “Interests of Certain Persons in the Merger” beginning on page 94 of this proxy statement/prospectus.

Granite will also incur transaction fees and costs related to formulating and implementing integration plans, including facilities and systems consolidation costs and employment-related costs. Granite continues to assess the magnitude of these costs, and additional unanticipated costs may be incurred in the Merger and the integration of the two companies’ businesses. Although Granite expects that the elimination of duplicative costs, as well as the realization of other efficiencies related to the integration of the businesses, should allow Granite to offset incremental Merger and integration-related costs over time, this net benefit may not be achieved in the near term, or at all. See “ —The integration of Layne may present significant challenges to Granite, and although Granite expects the Merger with Layne will result in cost savings, synergies and other benefits to Granite, Granite may not realize those benefits because of difficulties related to integration, the realization of synergies, and other challenges.”

As a result of the Merger, Granite’s goodwill, indefinite-lived intangible assets, and other intangible assets in its consolidated balance sheet will increase. If its goodwill, indefinite-lived intangible assets, or other intangible assets become impaired in the future, Granite would be required to record a material, non-cash charge to earnings, which would also reduce its stockholders’ equity.

Under GAAP, goodwill and indefinite-lived intangible assets are reviewed for impairment on an annual basis (or more frequently if events or circumstances indicate that their carrying value may not be recoverable) and other intangible assets if events or circumstances indicate that their carrying value may not be recoverable. If Granite’s goodwill, indefinite-lived intangible assets, or other intangible assets are determined to be impaired in the future, Granite will be required to record a material, non-cash charge to earnings during the period in which the impairment is determined.

The Merger Agreement contains provisions that limit Layne’s ability to pursue alternatives to the Merger, which could discourage a potential acquirer of Layne from making an alternative transaction proposal or could result in a competing proposal being at a lower price than it might otherwise be and, in certain circumstances, could require Layne to pay Granite a significant termination fee.

The Merger Agreement contains “no shop” provisions that, subject to limited exceptions, require that Layne may not (a) solicit, initiate, cause or knowingly facilitate or encourage the submission of any inquiries, proposals or offers or any other efforts or attempts that constitute or may reasonably be expected to lead to any acquisition proposal (as described in “The Merger Agreement—No Solicitation of Acquisition Proposals” beginning on page 109 of this proxy statement/prospectus), or engage in any discussions or negotiations with respect thereto or otherwise cooperate with or assist or participate in, or knowingly facilitate or encourage, any such inquiries,

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proposals, discussions or negotiations, or resolve to or publicly propose to take any of the foregoing actions, (b) approve or recommend, or resolve to or publicly propose to approve or recommend, any acquisition proposal or enter into any Merger Agreement, agreement-in-principle, letter of intent, share purchase agreement, asset purchase agreement, share exchange agreement, option agreement or other similar agreement relating to an acquisition proposal or enter into any letter of intent, agreement or agreement-in-principle requiring Layne to abandon, terminate or fail to consummate the Merger or (c) (1) withdraw, modify or qualify in a manner adverse to Granite or Merger Sub the recommendation of the Layne Board or the approval or declaration of advisability by the Layne Board of the Merger Agreement and the transactions contemplated thereby (including the Merger) or (2) approve or recommend, or resolve to or publicly propose to approve or recommend, any acquisition proposal.

The Merger Agreement also provides that Layne will be required to pay a termination fee of $16.0 million to Granite upon termination of the Merger Agreement under certain circumstances. These provisions might discourage a potential competing acquiror that might have an interest in acquiring all or a significant part of Layne from considering or proposing an acquisition even if it were prepared to pay consideration with a higher per share market price than that proposed in the Merger, or might result in a potential competing acquiror proposing to pay a lower per share price to acquire Layne than it might otherwise have proposed to pay.

The opinion delivered by Greentech will not reflect changes in circumstances between the date of such opinion and the completion of the Merger.

The Layne Board has not obtained an updated opinion as of the date of this proxy statement/prospectus from Greentech, its financial advisor. Changes in the operations and prospects of Layne or Granite, general market and economic conditions and other factors that may be beyond their control, and on which the opinions were based, may alter the value of Layne or Granite or the prices of Layne Common Stock or Granite Common Stock by the time the Merger is consummated. The opinion does not speak as of the time the Merger will be completed or as of any date other than the date of such opinion. Because Layne does not anticipate asking Greentech to update its opinion, the opinion only addresses the fairness of the Merger Consideration, from a financial point of view, as of the date of such opinion, subject to the various assumptions made, procedures followed, factors considered, and limitations of the review undertaken, qualifications contained and other matters set forth therein. Greentech’s opinion is included as Annex C to this proxy statement/prospectus. For a description of the opinion, please refer to “The Merger—Opinion of Financial Advisor to Layne” beginning on page 80 of this proxy statement/prospectus.

Layne executive officers and directors have financial interests in the Merger that may be different from, or in addition to, the interests of Layne stockholders.

Executive officers of Layne negotiated the terms of the Merger Agreement with their counterparts at Granite, and the Layne Board unanimously determined that the Merger Agreement and the Merger are in the best interests of Layne and its stockholders, approved and declared the Merger Agreement and unanimously recommended that Layne stockholders adopt the Merger Agreement. In considering these facts and the other information contained in this proxy statement/prospectus, you should be aware that Layne’s executive officers and directors have financial interests in the Merger that may be different from, or in addition to, the interests of Layne stockholders. For a detailed discussion of the special interests that Layne’s directors and executive officers may have in the Merger, see “The Merger—Interests of Certain Persons in the Merger” beginning on page 94 of this proxy statement/prospectus.

Risks Related to the Combined Company Following the Merger

The market price of Granite Common Stock and Granite’s results of operations may be affected by factors different from those affecting the market price of Layne Common Stock and Layne’s results of operations.

Layne stockholders will be entitled to receive the Merger Consideration, which is comprised of Granite Common Stock and will thus become Granite stockholders upon the consummation of the Merger. Granite’s

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business is different from that of Layne, and Granite’s results of operations, as well as the market price of Granite Common Stock, may be affected by factors different from those affecting Layne’s results of operations and the market price of Layne Common Stock. The market price of Granite Common Stock may fluctuate significantly following the Merger, including as a result of factors over which Granite has no control.

Failure to achieve expected benefits of the Merger and to integrate Layne’s operations with Granite’s could adversely affect Granite following the completion of the Merger and the market price of Granite Common Stock.

Although Granite expects to realize strategic, operational and financial benefits as a result of the Merger, Granite cannot be certain whether, and to what extent, such benefits will be achieved in the future. In particular, the success of the Merger will depend on achieving efficiencies and cost savings, and no assurances can be given that Granite will be able to do so. For example, costs associated with Layne’s legal proceedings and other loss contingencies may be greater than expected (including with respect to current and legacy projects undertaken and liabilities assumed by Layne and businesses that Layne has sold or discontinued). In addition, in order to obtain the benefits of the Merger, Granite must integrate Layne’s operations. Such integration may be complex and the failure to do so quickly and effectively may negatively affect earnings. Granite’s failure to create, or any significant delay in creating, an optimal operational and financial structure for the combined company may result in Granite being unable to realize the expected synergies and other intended benefits from the Merger.

In addition, the market price of Granite Common Stock may decline as a result of the Merger if the integration of Granite and Layne is unsuccessful, takes longer than expected or fails to achieve financial benefits to the extent anticipated by financial analysts or investors, or the effect of the Merger on Granite’s financial results is otherwise not consistent with the expectations of financial analysts or investors.

The pro forma financial statements included in this proxy statement/prospectus are presented for illustrative purposes only and may not be an indication of the combined company’s financial condition or results of operations following the Merger.

The pro forma financial statements contained in this proxy statement/prospectus are presented for illustrative purposes only, are based on various adjustments, assumptions and preliminary estimates and may not be an indication of the combined company’s financial condition or results of operations following the Merger for several reasons. See “Unaudited Pro Forma Condensed Combined Financial Information” beginning on page 39 of this proxy statement/prospectus. The actual financial condition and results of operations of the combined company following the Merger may not be consistent with, or evident from, these pro forma financial statements. In addition, the assumptions used in preparing the pro forma financial information may not prove to be accurate, and other factors may affect the combined company’s financial condition or results of operations following the Merger. Any potential decline in the combined company’s financial condition or results of operations may cause significant variations in the stock price of Granite following the Merger.

Layne stockholders will have a reduced ownership and voting interest in Granite after the Merger and, as a result, will be able to exert less influence over management.

Following the Merger, each Layne stockholder will become a stockholder of Granite with a percentage ownership of Granite after the Merger that is smaller than the stockholder’s percentage ownership of Layne. It is expected that immediately after consummation of the Merger the former stockholders of Layne as a group will own approximately 12% of the outstanding shares of Granite Common Stock on a fully diluted basis, excluding any shares that may subsequently be issued in connection with conversion of the 8.0% Convertible Notes. Because of this, Layne stockholders will have substantially less influence on the management and policies of Granite after the Merger than they now have with respect to the management and policies of Layne.

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Granite may be unable to hire and retain sufficient qualified personnel, and the loss of any of its key executive officers could adversely affect Granite.

Granite believes that its future success will depend in large part on its ability to attract and retain highly skilled, knowledgeable, sophisticated and qualified managerial and professional personnel, including, following the Merger, key employees of Layne. Key employees of Granite or Layne may depart for a variety of reasons, including because of issues relating to the difficulty of integration or accelerated retirement as a result of amounts received in connection with the Merger. Accordingly, no assurance can be given that Granite will be able to retain key employees of Granite or, following the Merger, Layne.

The combined company may require additional capital in the future, which may not be available to it on satisfactory terms, if at all.

The combined company will require liquidity to fund its operations and make interest and principal payments on its debt. To the extent that the funds generated by the combined company’s ongoing operations are insufficient to cover its liquidity requirements, it may need to raise additional funds through financings. If the combined company cannot obtain adequate capital or sources of credit on favorable terms, or at all, its business, operating results and financial condition could be adversely affected. Any future equity or debt financing may not be available on terms that are favorable to the combined company, if at all.

Other Risk Factors of Granite and Layne

Granite’s and Layne’s businesses are and will be subject to the risks described above. In addition, Granite and Layne are, and will continue to be, subject to the risks described in Granite’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017, and Layne’s Annual Report on Form 10-K for the fiscal year ended January 31, 2018, which is incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

A number of the statements made or incorporated by reference in this proxy statement/prospectus are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act, Section 27A of the Securities Act and Section 21E of the Exchange Act. Forward-looking statements are all statements made or incorporated by reference into this proxy statement/prospectus, other than statements of historical fact. In some cases, forward-looking statements can be identified by terminology such as “anticipates,” “believes,” “estimates,” “expects,” “intends,” “may,” “plans,” “projects,” “will,” “would,” and similar expressions or expressions of the negative of these terms. These statements include statements regarding the intent, belief or current expectations of each of Granite and Layne and their respective subsidiaries, their directors and their officers with respect to, among other things, future events, including the Merger, the respective financial results and financial trends expected to impact each of Granite and Layne prior to the completion of the Merger, or if the Merger is not completed, and expected to impact Granite thereafter, assuming the Merger is consummated.

Forward-looking statements are based upon certain underlying assumptions, including any assumptions mentioned with the specific statements, as of the date such statements were made. Such assumptions are in turn based upon internal estimates and analyses of market conditions and trends, management plans and strategies, economic conditions and other factors. While Granite and Layne believe these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond the control of Granite and Layne. By their nature, forward-looking statements and the assumptions underlying them are necessarily subject to risks and uncertainties inherent in projecting future conditions and results. Actual results may differ materially from the current expectations of Granite and Layne depending on a number of factors affecting their businesses and risks associated with the successful execution of the Merger and the integration and performance of their businesses following the Merger. These factors include, but are not limited to, those set forth under “Risk Factors” beginning on page 22 of this proxy statement/prospectus, and those set forth under “Forward-Looking Statements,” “Risk Factors” or any similar heading in the documents incorporated by reference herein.

Granite and Layne caution you not to place undue reliance on the forward-looking statements, which speak only as of the date of this proxy statement/prospectus in the case of forward-looking statements contained in this proxy statement/prospectus, or the dates of the documents incorporated by reference in this proxy statement/prospectus in the case of forward-looking statements made in those incorporated documents. Except as may be required by law, neither Granite nor Layne has any obligation to update or alter these forward-looking statements, whether as a result of new information, future events or otherwise.

Granite and Layne expressly qualify in their entirety all forward-looking statements attributable to Granite or Layne or any person acting on either of their respective behalf by the cautionary statements contained or referred to in this section.

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INFORMATION ABOUT GRANITE CONSTRUCTION INCORPORATED

Granite delivers infrastructure solutions for public and private clients primarily in the United States. Granite is one of the largest diversified heavy civil contractors and construction materials producers in the United States. Granite operates nationwide, serving both public and private sector clients. Within the public sector, Granite primarily concentrates on heavy-civil infrastructure projects, including the construction of streets, roads, highways, mass transit facilities, airport infrastructure, bridges, trenchless and underground utilities, power-related facilities, water-related facilities, utilities, tunnels, dams and other infrastructure-related projects. Within the private sector, Granite performs site preparation and infrastructure services for residential development, energy development, commercial and industrial sites, and other facilities, as well as provide construction management professional services. Granite’s business is organized into three reportable business segments. These business segments are: Construction, Large Project Construction and Construction Materials.

The four primary economic drivers of Granite business are (a) the overall health of the U.S. economy; (b) federal, state and local public funding levels; (c) population growth resulting in public and private development; and (d) the need to replace or repair aging infrastructure. A stagnant or declining economy will generally result in reduced demand for construction and construction materials in the private sector. This reduced demand increases competition for private sector projects and will ultimately also increase competition in the public sector as companies migrate from bidding on scarce private sector work to projects in the public sector. In addition, a stagnant or declining economy tends to produce less tax revenue for public agencies, thereby decreasing a source of funds available for spending on public infrastructure improvements. Some funding sources that have been specifically earmarked for infrastructure spending, such as diesel and gasoline taxes, are not as directly affected by a stagnant or declining economy, unless actual consumption is reduced or gasoline sales tax revenues decline consistent with fuel prices. However, even these can be temporarily at risk as federal, state and local governments take actions to balance their budgets. Additionally, fuel prices and more fuel efficient vehicles can have a dampening effect on consumption, resulting in overall lower tax revenue. Conversely, increased levels of public funding as well as an expanding or robust economy will generally increase demand for Granite’s services and provide opportunities for revenue growth and margin improvement.

In connection with entering into the Merger Agreement, Granite received a commitment letter for a new $370 million backstop facility. That backstop facility was obtained because the assumption of Layne’s outstanding debt and letters of credit would exceed the amount of indebtedness permitted under Granite’s then existing credit facility.

In connection with the Merger Agreement, Granite (a) has entered into the Credit Facility Amendment and (b) expects to enter into the NPA Amendment. The Credit Facility Amendment, among other things, (a) exempts Layne and its subsidiaries from the provisions of the Senior Credit Facility that would otherwise require them to guarantee Granite’s obligations under the Senior Credit Facility until the date upon which the 8.0% Convertible Notes have been paid or otherwise satisfied in full, (b) permits liens on certain assets of Layne and its subsidiaries securing the 8.0% Convertible Notes, (c) permits certain indebtedness outstanding under the 4.25% Convertible Notes and the 8.0% Convertible Notes and (d) increases the aggregate amount of uncommitted incremental revolving loans and/or incremental term loans that Granite may request under the Senior Credit Facility up to a maximum of $130,000,000, in each case as more fully disclosed in Granite’s Current Report on Form 8-K filed with the SEC on March 1, 2018. See “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus. The NPA Amendment is expected to, among other things, (a) permit the acquisition of Layne pursuant to the Merger Agreement, (b) exempt Layne and its subsidiaries from the provisions of the Note Purchase Agreement that would otherwise require them to guarantee Granite’s obligations under the Note Purchase Agreement until the earliest of the date upon which the 8.0% Convertible Notes have been paid or otherwise satisfied in full or certain other dates, if earlier, (c) permit liens on certain assets of Layne and its subsidiaries securing the 8.0% Convertible Notes and (d) permit certain indebtedness outstanding under the 4.25% Convertible Notes and the 8.0% Convertible Notes.

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Granite Common Stock is listed on NYSE under the symbol “GVA.” Granite Construction Company was originally incorporated in 1922. In 1990, Granite Construction Incorporated was formed as the holding company for Granite Construction Company and its wholly owned subsidiaries and was incorporated in Delaware.

Additional information about Granite is included in the documents incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

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INFORMATION ABOUT LAYNE CHRISTENSEN COMPANY

Layne is a leading global water management and services company, with more than 130 years of industry experience, providing responsible, sustainable, integrated solutions to address the world’s water, minerals and infrastructure challenges. Layne’s customers include government agencies, investor-owned utilities, industrial companies, global mining companies, engineering and consulting firms, oil and gas companies, power companies and agribusiness.

For its customers, Layne manages water throughout its lifecycle, including supply, treatment, delivery, maintenance and rehabilitation. Throughout each phase, Layne works to ensure compliance with complex state and federal regulations, and to meet increasingly high demand for quality, reliability and efficiency. Layne’s mineral services teams extract representative samples that accurately reflect the underlying mineral deposits for Layne’s global mining customers. Layne operates its business in three segments: Water Resources, Inliner, and Mineral Services.

Layne operates on a geographically dispersed basis with approximately 52 sales and operations offices located throughout North America, Brazil and through its affiliates in Latin America.

Shares of Layne Common Stock are listed on Nasdaq under the symbol “LAYN.” Layne was originally incorporated as Layne, Inc. in 1882.

Additional information about Layne is included in the documents incorporated by reference into this proxy statement/prospectus. See “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

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SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF GRANITE

The following table presents selected historical consolidated financial and operating data for Granite as of and for the fiscal years ended December 31, 2017, 2016, 2015, 2014, and 2013. The selected historical financial information presented below for each of the five years ended December 31, 2017 has been derived from Granite’s audited consolidated financial statements.

The information should be read in conjunction with Granite’s consolidated financial statements and the related notes thereto and the information under the heading “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in Granite’s Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on February 16, 2018, which are incorporated by reference in this proxy statement/prospectus. For additional information on documents incorporated by reference in this proxy statement/prospectus, see “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

Consolidated Statements of Operations

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Consolidated Balance Sheets

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SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA OF LAYNE

The following table presents summary historical consolidated financial data for Layne and its subsidiaries as of and for the fiscal years ended January 31, 2018, 2017, 2016, 2015 and 2014. The summary historical financial information presented below for each of the five years ended January 31, 2018 has been derived from Layne’s audited consolidated financial statements.

The information set forth below should be read in conjunction with Layne’s “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in Layne’s Annual Report on Form 10-K for the fiscal year ended January 31, 2018, which is incorporated by reference in this proxy statement/prospectus, and its consolidated financial statements and the notes thereto. For additional information on documents incorporated by reference in this proxy statement/prospectus, see “Where You Can Find More Information” beginning on page 144 of this proxy statement/prospectus.

Statements of Operations Data

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Balance Sheet Data (at period end)

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UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

The accompanying Pro Forma Income Statements for the periods presented combine the historical consolidated statements of income of Granite and Layne, giving effect to the Merger as if it had been completed on January 1, 2017, the beginning of the earliest period presented. The Pro Forma Income Statements assume that Granite, with a fiscal year that ends on December 31, acquired Layne, with a fiscal year that ends on January 31, and are to be read as if the Merger has been completed. The Pro Forma Income Statements for the fiscal year ended December 31, 2017 will include (a) Granite’s fiscal year ended December 31, 2017 and (b) Layne’s fiscal year ended January 31, 2018. The accompanying Pro Forma Balance Sheet as of December 31, 2017 combines the historical consolidated balance sheets of Granite as of December 31, 2017 and Layne as of January 31, 2018, giving effect to the Merger as if it had been completed on December 31, 2017.

The accompanying Pro Forma Financial Statements and related notes were prepared using the acquisition method of accounting with Granite considered the acquirer of Layne. Accordingly, the Merger Consideration to be paid in the Merger has been allocated to assets and liabilities of Layne based upon their estimated fair values as of the date of completion of the Merger. Any amount of the Merger Consideration that is in excess of the estimated fair values of assets acquired and liabilities assumed will be recorded as goodwill in Granite’s balance sheet after the completion of the Merger. The amount of goodwill that will be recorded in connection with the Merger depends on the market price of Granite Common Stock on the date of completion of the Merger. As a result of recent market volatility, the amount of goodwill that is ultimately recorded may vary significantly from the estimated goodwill on the Pro Forma Balance Sheet. As of the date of this proxy statement/prospectus, Granite has not completed the detailed valuation work necessary to arrive at the required estimates of the fair value of the Layne assets to be acquired and the liabilities to be assumed and the related allocation of purchase price, nor has it identified all adjustments necessary to conform Layne’s accounting policies to Granite’s accounting policies. A final determination of the fair value of Layne’s assets and liabilities will be based on the actual net tangible and intangible assets and liabilities of Layne that exist as of the date of completion of the Merger and, therefore, cannot be made prior to that date. Additionally, the value of the Merger Consideration to be paid by Granite to complete the Merger will be determined based on the trading price of Granite Common Stock in accordance with the Merger Agreement. Accordingly, the accompanying unaudited pro forma purchase price allocation is preliminary and is subject to further adjustments as additional information becomes available and as additional analyses are performed. Granite currently expects Construction, Cost of revenue, Selling, general and administrative expenses and amortization of discount and deferred financing costs to be the primary income statement line items that may be impacted by the determination of the final purchase price allocation from resulting amortization of tangible and intangible assets. Similarly, Granite currently expects investments in affiliates, goodwill, deferred income taxes, other noncurrent assets, long term debt, other long term liabilities and additional paid in capital to be the primary balance sheet line items that may be impacted by the final determination of the purchase price allocation. The preliminary unaudited pro forma purchase price allocation has been made solely for the purpose of preparing the accompanying Pro Forma Financial Statements. The preliminary purchase price allocation was based on Granite’s historical experience, data that was available through the public domain and Granite’s due diligence review of Layne’s business. Until the Merger is consummated, both companies are limited in their ability to share information with the other. Upon completion of the Merger, further valuation work will be performed. Increases or decreases in the fair value of relevant balance sheet amounts will result in adjustments to the balance sheet and/or statements of income until the purchase price allocation is finalized. There can be no assurance that such finalization will not result in material changes from the preliminary purchase price allocation included in the accompanying Statements.

The accompanying Pro Forma Financial Statements and related notes are being provided for illustrative purposes only and do not purport to represent what the actual consolidated results of operations or the consolidated balance sheet of Granite would have been had the Merger occurred on the dates assumed, nor are they necessarily indicative of Granite’s future consolidated results of operations or consolidated financial position. The Pro Forma Financial Statements are based upon currently available information and estimates and assumptions that Granite management believes are reasonable as of the date hereof. Any of the factors underlying these estimates and assumptions may change or prove to be materially different, and the estimates and assumptions may not be representative of facts existing at the closing date of the Merger.

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The accompanying Pro Forma Financial Statements have been developed from and should be read in conjunction with the audited consolidated financial statements of Granite contained in its Annual Report on Form 10-K for the fiscal year ended December 31, 2017, and of Layne contained in its Annual Report on Form 10-K for the fiscal year ended January 31, 2018, which is incorporated by reference in this proxy statement/prospectus.

The historical consolidated financial statements of Layne presented herein have been adjusted by condensing and disaggregating certain line items in order to conform to Granite’s financial statement presentation.

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Granite Construction Incorporated

Unaudited Condensed Combined Balance Sheet as of December 31, 2017

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Granite Construction Incorporated

Unaudited Pro Forma Condensed Combined Statement of Operations

For the year ended December 31, 2017