Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  NATIONAL GRID PLC
 2. Date of Event Requiring Statement (Month/Day/Year)
09/29/2015		 3. Issuer Name and Ticker or Trading Symbol
Dominion Midstream Partners, LP [DM]
(Last)
(First)
(Middle)
1-3 STRAND		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

LONDON, X0 WC2N 5EH		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
COMMON UNITS 6,783,373
I
Through indirect subsidiaries Northeast Transmission Co., Inc. and National Grid IGTS Corp. (1) (2)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
NATIONAL GRID PLC
1-3 STRAND
LONDON, X0 WC2N 5EH		     X    

Signatures

/S/ MACDARA NASH 10/09/2015
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) North East Transmission Co., Inc. is the beneficial owner of 6,450,854 Common Units and National Grid plc is the ultimate parent of North East Transmission Co., Inc. through its subsidiaries National Grid (US) Holdings Limited, National Grid (US) Investments 4 Limited, National Grid (US) Partner 1 Limited, National Grid North America Inc., National Grid USA, KeySpan Corporation, KeySpan Energy Corporation and The Brooklyn Union Gas Company.
(2) National Grid IGTS Corp. is the beneficial owner of 332,519 Common Units and National Grid plc is the ultimate parent of National Grid IGTS Corp. through its subsidiaries National Grid (US) Holdings Limited, National Grid (US) Investments 4 Limited, National Grid (US) Partner 1 Limited, National Grid North America Inc., National Grid USA, KeySpan Corporation, KeySpan Energy Corporation and National Grid Development Holdings Corp.
 
Remarks:
National Grid plc is the beneficial owner of 6,783,373 Common Units of Dominion Midstream Partners, LP held through its indirect subsidiaries North East Transmission Co., Inc. and National Grid IGTS Corp. as set forth above.

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