As filed with the Securities and Exchange Commission on May 28, 2004

                                       Registration Statement No. 333-__________
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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                        --------------------------------

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                        --------------------------------

                         WATTS WATER TECHNOLOGIES, INC.
             (Exact name of Registrant as Specified in Its Charter)


       Delaware                                        04-2916536
(State of Incorporation)                (I.R.S. Employer Identification Number)

                               815 Chestnut Street
                       North Andover, Massachusetts 01845
                                 (978) 688-1811
     (Address, including zip code and telephone number, including area code,
                  of Registrant's principal executive offices)

            WATTS WATER TECHNOLOGIES, INC. 2004 STOCK INCENTIVE PLAN
                            (Full Title of the Plan)
                        --------------------------------
                             Kenneth R. Lepage, Esq.
                            Assistant General Counsel
                         Watts Water Technologies, Inc.
                               815 Chestnut Street
                       North Andover, Massachusetts 01845
                                 (978) 688-1811
 (Name, address, including zip code and telephone number, including area code,
                             of agent for service)
                        --------------------------------

                                  With copy to:
                           Robert P. Whalen, Jr., Esq.
                               Goodwin Procter LLP
                                 Exchange Place
                        Boston, Massachusetts 02109-2881
                                 (617) 570-1000
                        --------------------------------

                         CALCULATION OF REGISTRATION FEE


====================================================================================================================================
                                                                                                   Proposed Maximum
                                                       Amount to be     Proposed Maximum Offering     Aggregate         Amount of
Title of Each Class of Securities to be Registered    Registered (1)       Price Per Share (2)      Offering Price  Registration Fee
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                            
Class A Common Stock, par value $0.10 per share ..   3,000,000 shares            $24.40               $73,200,000       $9,275
====================================================================================================================================



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(1)   This Registration Statement also relates to such indeterminate number of
      additional shares of Class A Common Stock, par value $.10 per share, of
      Watts Water Technologies, Inc. (the "Class A Common Stock") as may be
      required pursuant to the Watts Water Technologies, Inc. 2004 Stock
      Incentive Plan (the "Plan") in the event of a stock dividend, reverse
      stock split, split-up, recapitalization, forfeiture of stock under the
      Plan or other similar event.

(2)   This estimate is made pursuant to Rule 457(c) and (h) under the Securities
      Act of 1933, as amended, solely for the purposes of determining the amount
      of the registration fee. The registration fee is based upon the average of
      the high and low sales price for a share of Class A Common Stock, as
      reported on the New York Stock Exchange as of May 24, 2004, a date within
      five business days prior to filing this Registration Statement.

================================================================================


                                     PART I

              INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information.*

Item 2. Registrant Information and Employee Plan Annual Information.*

* The information required by Part I to be contained in the Section 10(a)
prospectus is not required to be filed with the Securities and Exchange
Commission (the "Commission") as part of this registration statement on Form S-8
(the "Registration Statement") in accordance with Rule 428 under the Securities
Act of 1933, as amended (the "Securities Act") and the Introductory Note to Part
I of Form S-8.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

      Watts Water Technologies, Inc. (the "Company") hereby incorporates by
reference into this Registration Statement the following documents which have
previously been filed with the Commission:

      o     the Company's Current Report on Form 8-K, filed on May 7, 2004;

      o     the Company's Current Report on Form 8-K, filed on May 25, 2004;

      o     the Company's Quarterly Report on Form 10-Q for the quarter ended
            March 31, 2004;

      o     the Company's Annual Report on Form 10-K for the year ended December
            31, 2003; and

      o     the description of the Company's Class A Common Stock contained in
            the Company's Registration Statement on Form 8-A filed with the
            Securities and Exchange Commission on June 22, 1995, and all
            amendments and reports updating the description.

      In addition, all documents subsequently filed with the Commission by the
Company pursuant to Sections 13(a) and 13(c), Section 14 and Section 15(d) of
the Securities Exchange Act of 1934, as amended (the "Exchange Act"), prior to
the filing of a post-effective amendment thereto that indicates that all
securities offered hereunder have been sold or that deregisters all securities
then remaining unsold, shall be deemed to be incorporated by reference in this
Registration Statement and to be a part hereof from the date of such documents.

Item 4. Description of Securities.

      Not applicable.

Item 5. Interests of Named Experts and Counsel.

      Not applicable.


Item 6. Indemnification of Directors and Officers.

      Section 145 of the Delaware General Corporation Law provides that a
corporation may indemnify any person who was or is a party or is threatened to
be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative, other than
an action by or in the right of the corporation, by reason of the fact that the
person is or was a director, officer, employee or agent of the corporation or is
or was serving at the corporation's request as a director, officer, employee or
agent of another corporation, partnership, joint venture, trust or other
enterprise, against expenses, including attorneys' fees, judgments, fines and
amounts paid in settlement actually and reasonably incurred by the person in
connection with the action, suit or proceeding if the person acted in good faith
and in a manner the person reasonably believed to be in or not opposed to the
best interests of the corporation, and, with respect to any criminal action or
proceeding, had no reasonable cause to believe the person's conduct was
unlawful. The power to indemnify applies to actions brought by or in the right
of the corporation as well, but only to the extent of expenses, including
attorneys' fees but excluding judgments, fines and amounts paid in settlement,
actually and reasonably incurred by the person in connection with the defense or
settlement of the action or suit. And with the further limitation that in these
actions, no indemnification shall be made in the event of any adjudication of
negligence or misconduct in the performance of the person's duties to the
corporation, unless a court believes that in light of all the circumstances
indemnification should apply.

      In accordance with Section 145 of the Delaware General Corporation Law,
Article X of the Restated Certificate of Incorporation, as amended, of the
Company provides that no director of the Company shall be personally liable to
the Company or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Company or its stockholders, (ii) for acts or omissions
not in good faith or which involve intentional misconduct or a knowing violation
of law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv)
for any transaction from which the director derived an improper personal
benefit.

      Article V of the Amended and Restated By-laws of the Company provides for
indemnification by the Company of its directors, officers and certain
non-officer employees under certain circumstances against expenses (including
attorneys fees) judgments, fines and amounts paid in settlement reasonably
incurred in connection with the defense or settlement of any threatened, pending
or completed legal proceeding in which any such person is involved by reason of
the fact that such person is or was a director, an officer or an employee of the
Company, or is acting in any capacity with other entities at the request of the
Company, if such person acted in good faith and in a manner he or she reasonably
believed to be in, or not opposed to, the best interests of the Company, and
with respect to criminal actions or proceedings, that such person had no
reasonable cause to believe his or her conduct was unlawful.

      Section 145(g) of the Delaware General Corporation Law and Article V of
the Amended and Restated By-laws of the Company provide that the Company shall
have the power to purchase and maintain insurance on behalf of its officers,
directors, employees and agents, against any liability asserted against and
incurred by such persons in any such capacity. The Company has obtained
insurance covering its directors and officers against losses and insuring the
Company against certain of its obligations to indemnify its directors and
officers.

      The Company has entered into indemnification agreements with its directors
and officers. The agreements provide that each director and officer will be
indemnified for expenses and liabilities incurred in any threatened, pending or
completed claim, action, suit or proceeding brought against such person as a
result of his or her status as a director or officer of the Company.

Item 7. Exemption from Registration Claimed.

      Not applicable.


Item 8. Exhibits.

      The following is a complete list of exhibits filed or incorporated by
reference as part of this Registration Statement.

Exhibit
-------

4.1   Restated Certificate of Incorporation, as amended (incorporated by
      reference to Exhibit 4.1 to the Company's Registration Statement on Form
      S-3, File No. 333-105989).
4.2   Amended and Restated By-laws, as amended (incorporated by reference to
      Exhibit 4.2 to the Company's Registration Statement on Form S-3, File No.
      333-105989).
5.1   Opinion of Goodwin Procter LLP.*
23.1  Consent of Goodwin Procter LLP (included in Exhibit 5.1 hereto).
23.2  Consent of KPMG LLP.*
24.1  Powers of Attorney (included in the signature page of this Registration
      Statement).
99.1  Watts Water Technologies, Inc. 2004 Stock Incentive Plan (incorporated by
      reference to Appendix B to the Company's Proxy Statement, filed with the
      Commission on March 31, 2004 pursuant to Section 14(a) of the Exchange
      Act).

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* Filed herewith.

Item 9. Undertakings.

      (a)   The Company hereby undertakes:

            (1) To file, during any period in which offers or sales are being
            made, a post-effective amendment to this Registration Statement:

                  (i) To include any prospectus required by Section 10(a)(3) of
            the Securities Act;

                  (ii) To reflect in the prospectus any facts or events arising
            after the effective date of the Registration Statement (or the most
            recent post-effective amendment thereof) which, individually or in
            the aggregate, represent a fundamental change in the information set
            forth in the Registration Statement. Notwithstanding the foregoing,
            any increase or decrease in volume of securities offered (if the
            total dollar value of securities offered would not exceed that which
            was registered) and any deviation from the low or high end of the
            estimated maximum offering range may be reflected in the form of
            prospectus filed with the Commission pursuant to Rule 424(b) if, in
            the aggregate, the changes in volume and price represent no mater
            than a 20% change in the maximum aggregate offering price set forth
            in "Calculation of Registration Fee" table in the effective
            registration statement; and

                  (iii) To include any material information with respect to the
            plan of distribution not previously disclosed in the Registration
            Statement or any material change to such information in the
            Registration Statement;

      provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) herein do not
      apply if the information required to be included in a post-effective
      amendment by those paragraphs is contained in periodic reports filed by
      the undersigned registrant pursuant to Section 13 or Section 15(d) of the
      Exchange Act that are incorporated by reference in the Registration
      Statement;


            (2) That, for the purposes of determining any liability under the
            Securities Act, each such post-effective amendment shall be deemed
            to be a new registration statement relating to the securities
            offered therein, and the offering of such securities at that time
            shall be deemed to be the initial bona fide offering thereof; and

            (3) To remove from registration by means of a post-effective
            amendment any of the securities being registered which remain unsold
            at the termination of the offering.

      (b) The Company hereby undertakes that, for purposes of determining any
liability under the Securities Act, each filing of the Company's annual report
pursuant to Section 13(a) or 15(d) of the Exchange Act and each filing of an
employee benefit plan's annual report pursuant to Section 15(d) of the Exchange
Act that is incorporated by reference in the Registration Statement shall be
deemed to be a new registration statement relating to the securities offered
therein, and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.

      (c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to the directors, officers, and controlling
persons of the Company pursuant to the foregoing provisions, or otherwise, the
Company has been advised that in the opinion of the Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefor, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the Company of expenses
incurred or paid by a director, officer, or controlling person of the Company in
the successful defense of any action, suit, or proceeding) is asserted by such
director, officer, or controlling person in connection with the securities being
registered, the Company will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.


                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the city of North Andover, The Commonwealth of Massachusetts, on
May 28, 2004.

                                        WATTS WATER TECHNOLOGIES, INC.


                                        By: /s/ Patrick S. O'Keefe
                                            ----------------------
                                            Patrick S. O'Keefe
                                            Chief Executive Officer and Director


      KNOW ALL BY THESE PRESENTS that each individual whose signature appears
below constitutes and appoints each of Patrick S. O'Keefe and William C.
McCartney as such person's true and lawful attorney-in-fact and agent with full
power of substitution and resubstitution, for such person in such person's name,
place and stead, in any and all capacities, to sign any and all amendments
(including post-effective amendments) to this Registration Statement, and to
file the same, with all exhibits thereto, and all documents in connection
therewith, with the Securities and Exchange Commission, granting unto each said
attorney-in-fact and agent full power and authority to do and perform each and
every act and thing requisite and necessary to be done in and about the
premises, as fully to all intents and purposes as such person might or could do
in person, hereby ratifying and confirming all that any said attorney-in-fact
and agent, or any substitute or substitutes of any of them, may lawfully do or
cause to be done by virtue hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

        Signature                        Title                       Date
        ---------                        -----                       ----

 /s/ Patrick S. O'Keefe     Chief Executive Officer and Director   May 28, 2004
----------------------      (Principal Executive Officer)
Patrick S. O'Keefe

/s/ William C. McCartney    Chief Financial Officer, Treasurer     May 28, 2004
------------------------    and Secretary (Principal Financial
William C. McCartney        Officer and Principal Accounting
                            Officer)

/s/ Timothy P. Horne        Director                               May 24, 2004
--------------------
Timothy P. Horne

/s/ Kenneth J. McAvoy       Director                               May 28, 2004
---------------------
Kenneth J. McAvoy

/s/ Gordon W. Moran         Director                               May 24, 2004
-------------------
Gordon W. Moran

/s/ Daniel J. Murphy        Director                               May 28, 2004
--------------------
Daniel J. Murphy

/s/ Roger A. Young          Director                               May 28, 2004
------------------
Roger A. Young

/s/ John K. McGillicuddy    Director                               May 21, 2004
------------------------
John K. McGillicuddy


                                  EXHIBIT INDEX

Exhibit
  No.             Description
  ---             -----------

  4.1    --    Restated Certificate of Incorporation, as amended (incorporated
               by reference to Exhibit 4.1 to the Company's Registration
               Statement on Form S-3, File No. 333-105989).

  4.2    --    Amended and Restated By-laws, as amended (incorporated by
               reference to Exhibit 4.2 to the Company's Registration Statement
               on Form S-3, File No. 333-105989).

  5.1    --    Opinion of Goodwin Procter LLP.*

 23.1    --    Consent of Goodwin Procter LLP (included in Exhibit 5.1 hereto).

 23.2    --    Consent of KPMG LLP.*

 24.1    --    Powers of Attorney (included in the signature page of this
               Registration Statement).

 99.1    --    Watts Water Technologies, Inc. 2004 Stock Incentive Plan
               (incorporated by reference to Appendix B to the Company's Proxy
               Statement, filed with the Commission on March 31, 2004 pursuant
               to Section 14(a) of the Exchange Act).

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* Filed herewith.