FOURTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

Exhibit 10.1.4

FOURTH AMENDMENT

          FOURTH AMENDMENT, dated as of March 15, 2006 (this “Amendment”), to the Amended and Restated Credit Agreement, dated as of May 12, 2004 (the “Credit Agreement”), among INFRASOURCE SERVICES, INC., a Delaware corporation (“Holdings”), INFRASOURCE INCORPORATED, a Delaware corporation (the “Borrower”), the several banks and other financial institutions or entities from time to time parties thereto (the “Lenders”), LASALLE BANK NATIONAL ASSOCIATION, as syndication agent, and BARCLAYS BANK PLC, as administrative agent (the “Administrative Agent”).

W I T N E S S E T H:

          WHEREAS, the Borrower has requested that the Lenders agree to amend certain provisions in the Credit Agreement upon the terms and subject to the conditions set forth herein; and

          WHEREAS, the Lenders have agreed to such amendments only upon the terms and subject to the conditions set forth herein;

          NOW, THEREFORE, in consideration of the premises and the mutual covenants contained herein and in the Credit Agreement, the parties hereto hereby agree as follows:

          1. Defined Terms. Unless otherwise defined herein, all capitalized terms used herein shall have the meanings given to them in the Credit Agreement.

          2. Amendment to Section 8 (Events of Default). Section 8 of the Credit Agreement is hereby amended by deleting clause (i) of paragraph (l) of such Section in its entirety and substituting in lieu thereof the following:

     ”(i) any “person” or “group” (as such terms are used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), excluding the Permitted Investors, shall become, or obtain rights (whether by means or warrants, options or otherwise) to become, the “beneficial owner” (as defined in Rule 13(d)(3) and 13(d)(5) of the Exchange Act), directly or indirectly, of more than 35% of the outstanding common stock of Holdings; or”

          3. Representations and Warranties. (a) Credit Agreement Representations and Warranties. On and as of the date hereof and after giving effect to this Amendment, Holdings and the Borrower hereby confirm, reaffirm and restate the representations and warranties set forth in Sections 4 of the Credit Agreement mutatis mutandis, except to the extent that such representations and warranties expressly relate to a specific earlier date in which case Holdings and the Borrower hereby confirm, reaffirm and restate such representations and warranties as of such earlier date.

          (b) Power; Authorization; Enforceable Obligations. Each Loan Party has the requisite corporate or other power and authority, and the legal right, to make, deliver and perform the Loan Documents to which it is a party, as amended, in the case of the Credit Agreement, by this Amendment. Each Loan Party has taken all necessary steps to authorize the execution, delivery and performance of Loan Documents to which it is a party, as amended, in the case of the Credit Agreement, by this Amendment. The Credit Agreement, as amended by this Amendment, continues to constitute a

legal, valid and binding obligation of each Loan Party party thereto, enforceable against each such Loan Party in accordance with its terms, except as enforceability maybe limited by applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the enforcement of creditors’ rights generally and by general equitable principles (whether enforcement is sought by proceedings in equity or at law).

          (c) No Legal Bar. The execution, delivery and performance of this Amendment and any other related documents will not violate any Requirement of Law or any material Contractual Obligation of any Group Member and will not result in, or require, the creation or imposition of any Lien on any of their respective properties or revenue pursuant to any Requirement of Law or any such material Contractual Obligation (other than the Liens created by the Security Documents).

          4. Conditions to Effectiveness. This Amendment shall become effective on the date upon which the Administrative Agent shall have received this Amendment, executed by the Administrative Agent, the Borrower, Holdings, the Subsidiary Guarantors and the Required Lenders.

          5. Continuing Effect. Except as expressly amended hereby, the Credit Agreement shall continue to be and shall remain in full force and effect in accordance with its terms.

          6. Expenses. The Borrower agrees to pay and reimburse the Administrative Agent for all of its reasonable out-of-pocket costs and expenses incurred in connection with the negotiation, preparation, execution and delivery of this Amendment, including the reasonable fees and expenses of counsel.

          7. Counterparts. This Amendment may be executed on any number of separate counterparts, and all of said counterparts taken together shall be deemed to constitute one and the same instrument. Delivery of an executed signature page of this Amendment by facsimile transmission shall be effective as delivery of a manually executed counterpart hereof.

          8. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

          IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed and delivered by their proper and duly authorized officers as of the day and year first above written.

		INFRASOURCE INCORPORATED
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Chief Financial Officer
		INFRASOURCE SERVICES, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Chief Financial Officer
		BARCLAYS BANK PLC, as Administrative Agent      and as a Lender
		By:		/s/ David Barton
				Name: David Barton Title: Associate Director
		LASALLE BANK NATIONAL ASSOCIATION, as Syndication Agent      and as a Lender
		By:		/s/ Nick Lotz
				Name: Nick Lotz Title: Commercial Banking Officer

		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Commerce Bank, N.A.
		[Name of Lender]
		By:		/s/ Michael P. Thomson
				Name: Michael P. Thomson Title: Vice President
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		JP Morgan Chase Bank N.A.
		By:		/s/ Lee P. Brennan
				Name: Lee P. Brennan Title: Vice President
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		WACHOVIA BANK, NATIONAL ASSOCIATION
		By:		/s/ Stephen T. Dorosh
				Name: Stephen T. Dorosh Title: Vice President
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		RZB Finance LLC
		[Name of Lender]
		By:		/s/ Christoph Hoedl
				Name: Christoph Hoedl Title: Group Vice President
		By:		/s/ Nadia Nedelcheva
				Name: Nadia Nedelcheva Title: Vice President

		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		ELF Funding Trust I
		[Name of Lender]
		By: Highland Capital Management, L.P., as Collateral Manager By: Strand Advisors, Inc., Its General Partner
		By:		/s/ Chad Schramek
				Name: Chad Schramek
				Title: Assistant Treasurer
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Restoration Funding CLO, LTD
		[Name of Lender]
		By: Highland Capital Management, L.P., as Collateral Manager By: Strand Advisors, Inc., Its General Partner
		By:		/s/ Chad Schramek
				Name: Chad Schramek
				Title: Assistant Treasurer

		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Highland Legacy Limited
		[Name of Lender]
		By: Highland Capital Management, L.P., as Collateral Manager By: Strand Advisors, Inc., Its General Partner
		By:		/s/ Chad Schramek
				Name: Chad Schramek
				Title: Assistant Treasurer
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Gleneagles CLO, Ltd.
		[Name of Lender]
		By: Highland Capital Management, L.P., as Collateral Manager By: Strand Advisors, Inc., Its General Partner
		By:		/s/ Chad Schramek
				Name: Chad Schramek
				Title: Assistant Treasurer
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Highland Floating Rate LLC
		[Name of Lender]
		By:		/s/ Joe Dougherty
				Name: Joe Dougherty Title: Senior Vice President

		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Highland Floating Rate Advantage Fund
		[Name of Lender]
		By:		/s/ Joe Dougherty
				Name: Joe Dougherty Title: Senior Vice President
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Oligra 43
		[Name of Lender]
		By:		/s/ Karen Thompson
				Name: Karen Thompson Title: Loans Officer
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		FOXE BASIN CLO 2003, LTD.
		[Name of Lender]
		By: GSO Capital Partners LP as Collateral Manager
		By:		/s/ Lee M. Shalman
				Name: Lee M. Shalman
				Title: Authorized Signatory
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Denali Capital LLC, managing member of DC Funding Partners, portfolio manager for DENALI CAPITAL CLO I, LTD, or an affiliate.
		[Name of Lender]
		By:		/s/ Kelli C. Marti
				Name: Kelli C. Marti Title: Senior Vice President

		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Denali Capital LLC, managing member of DC Funding Partners, portfolio manager for DENALI CAPITAL CLO III, LTD, or an affiliate.
		[Name of Lender]
		By:		/s/ Kelli C. Marti
				Name: Kelli C. Marti Title: Senior Vice President
		INFRASOURCE INCORPORATED FOURTH AMENDMENT
		Denali Capital LLC, managing member of DC Funding Partners, portfolio manager for DENALI CAPITAL CLO VI, LTD, or an affiliate.
		[Name of Lender]
		By:		/s/ Kelli C. Marti
				Name: Kelli C. Marti Title: Senior Vice President

ACKNOWLEDGEMENT AND CONSENT

          Each of the undersigned Subsidiary Guarantors hereby acknowledges and consents to the foregoing Amendment.

		INFRASOURCE CORPORATE SERVICES, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		DASHIELL HOLDINGS CORPORATION
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		DASHIELL LTD
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		DACON GP LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		DACON LTD
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE TEXAS HOLDINGS GP LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE TEXAS HOLDINGS LP LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer

		M.J. ELECTRIC, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		BLAIR PARK SERVICES, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		OSP CONSULTANTS, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE POWER CALIFORNIA, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		OSP TELCOM, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		RJE TELECOM, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		SUNESYS, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer

		SUNESYS OF VIRGINIA, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		CHOWNS, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		TRINITY INDUSTRIES, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND SERVICES, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE POWER, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND INSTALLATION, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		MECHANICAL SPECIALTIES, INCORPORATED
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer

		INFRASOURCE MID-ATLANTIC, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND CONSTRUCTION SERVICES, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND CONSTRUCTION, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND CONSTRUCTION, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE MASLONKA, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND CONSTRUCTION CALIFORNIA, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer

		INFRASOURCE CONCRETE & PAVING SERVICES, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE TRANSMISSION SERVICES COMPANY
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE MASLONKA CA, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		IUC IOWA, LLC
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		INFRASOURCE UNDERGROUND SERVICES CANADA, INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer
		EHV POWER USA INC.
		By:		/s/ Terence R. Montgomery
				Name: Terence R. Montgomery Title: Senior Vice President & Treasurer