364-DAY REVOLVING CREDIT AGREEMENT

Exhibit 10.1

EXECUTION VERSION

$500,000,000

364-DAY REVOLVING CREDIT AGREEMENT

among

DOMINION RESOURCES, INC.,

The Several Lenders from Time to Time Parties Hereto,

THE ROYAL BANK OF SCOTLAND PLC,

as Administrative Agent,

BARCLAYS BANK PLC AND MORGAN STANLEY BANK,

as Co-Syndication Agents,

CITIBANK N.A. AND THE BANK OF NOVA SCOTIA ,

as Co-Documentation Agents

RBS SECURITIES CORPORATION D/B/A RBS GREENWICH CAPITAL,

as Lead Arranger and Bookrunner

Dated as of July 30, 2008

Table of Contents

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SCHEDULES

EXHIBITS

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364-DAY REVOLVING

CREDIT AGREEMENT

364-DAY REVOLVING CREDIT AGREEMENT (this “ Credit Agreement ”), dated as of July 30, 2008 among DOMINION RESOURCES, INC., a Virginia corporation (together with its permitted successors and assigns, the “ Borrower ”), the several banks and other financial institutions from time to time parties to this Credit Agreement (each a “ Lender ” and, collectively, the “Lenders”), THE ROYAL BANK OF SCOTLAND PLC, a public limited company incorporated in the United Kingdom and registered under the laws of Scotland, as administrative agent for the Lenders hereunder (in such capacity, the “ Administrative Agent ”), BARCLAYS BANK PLC and MORGAN STANLEY BANK, as Co-Syndication Agents and, CITIBANK N.A. and THE BANK OF NOVA SCOTIA, as Co-Documentation Agents.

The parties hereto hereby agree as follows:

SECTION 1. DEFINITIONS AND ACCOUNTING TERMS

1.1  Definitions .

As used herein, the following terms shall have the meanings herein specified unless the context otherwise requires. Defined terms herein shall include in the singular number the plural and in the plural the singular:

“ Adjusted Base Rate ” means the Base Rate plus the Applicable Percentage for Base Rate Loans.

“ Adjusted Eurodollar Rate ” means the Eurodollar Rate plus the Applicable Percentage for Eurodollar Revolving Loans.

“ Administrative Agent ” means The Royal Bank of Scotland plc and any successors and assigns in such capacity.

“ Affiliate ” means, with respect to any Person, any other Person directly or indirectly controlling (including but not limited to all directors and officers of such Person), controlled by or under direct or indirect common control with such Person. A Person shall be deemed to control a corporation or other entity if such Person possesses, directly or indirectly, the power (i) to vote 20% or more of the securities having ordinary voting power for the election of directors or other managing persons of such corporation or other entity or (ii) to direct or cause direction of the management and policies of such corporation or other entity, whether through the ownership of voting securities, by contract or otherwise.

“ Applicable Percentage ” means, for (x) Eurodollar Revolving Loans, the LIBOR Market Rate Spread in effect from time to time, and (y) all other Revolving Loans made to the Borrower, 0%. Any adjustment in the Applicable Percentages shall be applicable to all existing Loans as well as any new Loans.

“ Available Revolving Loan Commitment ” means, as of any date of determination, the Revolving Loan Commitment as of such date minus the aggregate principal amount of all Loans outstanding as of such date.

“ Bankruptcy Code ” means the Bankruptcy Code in Title 11 of the United States Code, as amended, modified, succeeded or replaced from time to time.

“ Base Rate ” means, for any day, a simple rate per annum equal to the greater of (a) the Prime Rate for such day or (b) the sum of one-half of one percent (.50%) plus the Federal Funds Rate for such day.

“ Base Rate Loan ” means a Loan that bears interest at an Adjusted Base Rate.

“ Borrower ” has the meaning set forth in the preamble hereof.

“ Business Day ” means any day other than a Saturday, a Sunday, a legal holiday or a day on which banking institutions are authorized or required by law or other governmental action to close in New York, New York; provided that in the case of Eurodollar Revolving Loans, such day is also a day on which dealings between banks are carried on in Dollar deposits in the London interbank market.

“ Capital Stock ” means any and all shares, interests, participations or other equivalents (however designated) of capital stock of a corporation, any and all equivalent ownership interests in a Person (other than a corporation) and any and all warrants, rights or options to purchase any of the foregoing.

“ Capitalization ” means the sum of (a) Total Funded Debt plus (b) Net Worth.

“ Change of Control ” means (i) the direct or indirect acquisition by any person (as such term is defined in Section 13(d) of the Securities and Exchange Act of 1934, as amended) of beneficial ownership of more than 50% of the outstanding shares of the capital stock of the Borrower entitled to vote generally for the election of directors of the Borrower or (ii) VaPower shall cease to be a Subsidiary of the Borrower; provided , however , that should VaPower cease to be a Subsidiary of the Borrower by virtue of its merger with or into the Borrower, or with or into any other Subsidiary of the Borrower, such merger will not constitute a Change of Control.

“ Closing Date ” means the date hereof.

“ Code ” means the Internal Revenue Code of 1986, as amended from time to time.

“ Commitment ” means, with respect to each Lender, such Lender’s share of the Revolving Loan Commitment based upon such Lender’s Commitment Percentage.

“ Commitment Fees ” has the meaning set forth in Section 3.4(a).

“ Commitment Fee Margin ” means Commitment Fees payable by the Borrower, the appropriate applicable percentages, in each case, corresponding to the Rating of the Borrower in effect from time to time as shown below:

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