LIMITED POWER OF ATTORNEY
FOR SECTION 16 REPORTING OBLIGATIONS
AND NOTICES OF PROPOSED SALES OF SECURITIES
UNDER RULE 144

Know all by these presents, that the undersigned hereby makes,
constitutes and appoints each of Kenneth R. Lepage
and Amy B. Clark, signing singly and each acting individually,
as the undersigned's true and lawful attorney-in-fact with full power and
authority as hereinafter described to:
(1)	execute for and on behalf of the undersigned, in the
undersigned's capacity as an officer and/or director of Watts Water
Technologies, Inc. (the "Company"), Forms 3, 4, and 5 (including any
amendments thereto) in accordance with Section 16(a) of the Securities
Exchange Act of 1934 and the rules thereunder (the "Exchange Act");
(2)	execute for and on behalf of the undersigned Forms 144
(including any amendments thereto) pursuant to Rule 144 under the
Securities Act of 1933 (the "Securities Act");
(3)	do and perform any and all acts for and on behalf of the
undersigned which may be necessary or desirable to prepare, complete
and execute any such Form 3, 4, or 5 or Form 144, prepare, complete and
execute any amendment or amendments thereto, and timely deliver and
file such form with the United States Securities and Exchange
Commission and any stock exchange or similar authority, including
without limitation the execution and filing of a Form ID or any successor
form thereto for the purpose of obtaining EDGAR access codes;
(4)	seek or obtain, as the undersigned's representative and
on the undersigned's behalf, information regarding transactions in the
Company's securities from any third party, including brokers, employee
benefit plan administrators and trustees, and the undersigned hereby
authorizes any such person to release any such information to such
attorney-in-fact and approves and ratifies any such release of
information; and
(5)	take any other action of any type whatsoever in
connection with the foregoing which, in the opinion of such
attorney-in-fact, may be of benefit to, in the best interest of, or legally
required by, the undersigned, it being understood that the documents
executed by such attorney-in-fact on behalf of the undersigned pursuant
to this Power of Attorney shall be in such form and shall contain such
terms and conditions as such attorney-in-fact may approve in such
attorney-in-fact's discretion.
The undersigned hereby grants to each such attorney-in-fact full
power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be done in the exercise of
any of the rights and powers herein granted, as fully to all intents and
purposes as the undersigned might or could do if personally present, with
full power of substitution or revocation, hereby ratifying and confirming
all that such attorney-in-fact, or such attorney-in-fact's substitute or
substitutes, shall lawfully do or cause to be done by virtue of this power
of attorney and the rights and powers herein granted.  The undersigned
acknowledges that the foregoing attorneys-in-fact, in serving in such
capacity at the request of the undersigned, are not assuming nor
relieving, nor is the Company assuming nor relieving, any of the
undersigned's responsibilities to comply with Section 16 of the Exchange
Act or Rule 144 under the Securities Act.  The undersigned
acknowledges that neither the Company nor the foregoing
attorneys-in-fact assume (i) any liability for the undersigned's
responsibility to comply with the requirements of the Exchange Act and
Securities Act, (ii) any liability of the undersigned for any failure to
comply with such requirements, or (iii) any obligation or liability of the
undersigned for profit disgorgement under Section 16(b) of the Exchange
Act.
This Power of Attorney shall remain in full force and effect until
the undersigned is no longer required to file Forms 3, 4, and 5 with
respect to the undersigned's holdings of and transactions in securities
issued by the Company, unless earlier revoked by the undersigned in a
signed writing delivered to the foregoing attorneys-in-fact.
IN WITNESS WHEREOF, the undersigned has caused this
Power of Attorney to be executed as of this 20th day of February 2012.


/s/ William C. McCartney
William C. McCartney