<PAGE>
 
                                                     REGISTRATION NO. 33-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    Form S-8
                             REGISTRATION STATEMENT
                                     under
                           THE SECURITIES ACT OF 1933

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

                                Aquarion Company
             (Exact name of Registrant as specified in its charter)

Delaware                                                   06-0852232
(State or other jurisdiction of                            (I.R.S. Employer
incorporation or organization)                            Identification Number)

                                835 Main Street
                              Bridgeport, CT 06601
   (Address, including zip code, of Registrant's principal executive office)

                     Aquarion Company Stock Incentive Plan
             Aquarion Company Directors' Deferred Compensation Plan
                   Aquarion Company Long-Term Incentive Plan
                           (Full title of the Plans)

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

                                Janet M. Hansen
          Senior Vice President, Chief Financial Officer and Treasurer
                                Aquarion Company
                                835 Main Street
                              Bridgeport, CT 06601
                                 (203) 335-2333
(Name, address and telephone number, including area code, of agent for service)

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

                                   Copies to:
                             Joel S. Hoffman, Esq.
                           Simpson Thacher & Bartlett
                              425 Lexington Avenue
                            New York, New York 10017

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

                        CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
 =======================================================================================================
                                                             PROPOSED        PROPOSED   
            TITLE OF                                         MAXIMUM         MAXIMUM         AMOUNT OF   
         SECURITIES TO                AMOUNT TO          OFFERING PRICE     AGGREGATE      REGISTRATION  
         BE REGISTERED              BE REGISTERED         PER SHARE(2)    OFFERING PRICE      FEE(2)      
- --------------------------------------------------------------------------------------------------------
<S>                               <C>                  <C>                <C>              <C>
Common Stock without par value       1,200,000 shares(1)     $24.6875        $29,625,000     $10,215
========================================================================================================
</TABLE>

(1)  This Registration Statement also pertains to Series A Junior Participating
     Preferred Stock Purchase Rights ("Rights") of the Registrant.  Until the
     occurrence of certain prescribed events, the Rights are not exercisable,
     will be evidenced by the certificates for the Common Stock and will be
     transferred along with and only with the Common Stock.
(2)  Estimated solely for calculating the registration fee and calculated
     pursuant to Rule 457(c), based on the average of the high and low sale
     prices of the Common Stock on April 28, 1994 as reported on the New York
     Stock Exchange Composite Tape.

================================================================================
<PAGE>
 
                                    PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

   The following documents filed with the Securities and Exchange Commission by
Aquarion Company (the "Company") are hereby incorporated in this Registration
Statement by reference:

    (a) The Company's Annual Report on Form 10-K for the fiscal year ended
    December 31, 1993.

   All documents filed by the Company pursuant to Sections 13(a), 13(c), 14 and
15(d) of the Exchange Act after the date of this Registration Statement and
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which 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 filing such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any other subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
statement. Any such statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part of this Registration
Statement.

ITEM 4.  DESCRIPTION OF SECURITIES.

   Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

   The financial statements incorporated in this Prospectus by reference to the
Annual Report on Form 10-K of Aquarion Company for the year ended December 31,
1993, have been so incorporated in reliance on the report of Price Waterhouse,
independent accountants, given on the authority of said firm as experts in
auditing and accounting.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

   The Company's Restated Certificate of Incorporation includes provisions which
have the purpose of limiting the personal liability of its directors for
monetary damages for breach of their duty of care to the full extent permissible
under Delaware law.

    The Delaware General Corporation Law authorizes a corporation's Board of
Directors to grant indemnity to officers and directors for certain liabilities,
including reimbursement of expenses incurred, arising under the Securities Act
of 1933, as amended (the "Securities Act").  Article VIII of the Company's By-
laws provides for indemnification of its officers, directors, employees and
other agents to the maximum extent permitted by Delaware law.

    The Company has purchased directors' and officers' liability insurance
covering certain liabilities incurred by its directors in connection with the
performance of their duties.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

   Not applicable

ITEM 8.  EXHIBITS.

   4.1 Aquarion Company Stock Incentive Plan - incorporated by reference to
       Exhibit A to the Company's Proxy Statement for its Annual Meeting held on
       April 26, 1994

   4.2 Aquarion Company Directors' Deferred Compensation Plan - incorporated by
       reference to Exhibit B to the Company's Proxy Statement for its Annual
       Meeting held on April 26, 1994

                                       2
<PAGE>
 
   4.3  Aquarion Company Long-Term Incentive Plan*

   5    Opinion of Wiggin & Dana*

   23.1 Consent of Price Waterhouse*

   23.2 Consent of Wiggin & Dana (included in the opinion filed as Exhibit 5)*

   24   Power of Attorney*

- ----------------
*   Filed herewith

ITEM 9.  UNDERTAKINGS.

   (a) The undersigned Registrant 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 this 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 this
   Registration Statement;

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

provided, however, that the undertakings set forth in paragraphs (i) and (ii)
above 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 Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act
that are incorporated by reference in this Registration Statement.

   (2)  That, for the purpose 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.

   (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 undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, 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 this Registration Statement shall be deemed to be a
new registration statement relating to the securities offered herein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

  (h)  Insofar as indemnification for liabilities arising under the Securities
Act of 1933, as amended (the "Securities Act"), may be permitted to directors,
officers or controlling persons of the Registrant pursuant to the foregoing
provisions, or otherwise, the Registrant has been advised that in the opinion of
the Securities and Exchange Commission such indemnification is against public
policy as expressed in the Securities Act and is, therefore, unenforceable. In
the event that a claim for indemnification against such liabilities (other than
the payment by the Registrant of expenses incurred or paid by a director,
officer or controlling person of the Registrant in the successful defense of any
action, suit or proceeding) is asserted against the Registrant by such director,
officer or controlling person in connection with the securities being
registered, the Registrant 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 policy
as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                       3
<PAGE>
 
                                   SIGNATURES

   Pursuant to the requirements of the Securities Act of 1933, Aquarion Company
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 Bridgeport, State of Connecticut, on this 4th, day of
May, 1994.

                              AQUARION COMPANY

                              By         Janet M. Hansen 
                                ----------------------------------------
                                         Janet M. Hansen
                                      Senior Vice President,                
                                     Chief Financial Officer and
                                             Treasurer

  Pursuant to the requirements of the Securities Act of 1933, this Registration
Statement has been signed by the following persons in the capacities indicated
on this 4th day of May, 1994.


         William S. Warner*               CHAIRMAN OF THE BOARD OF DIRECTORS
- --------------------------------------               AND DIRECTOR
         William S. Warner


         Jack E. McGregor*                PRESIDENT, CHIEF EXECUTIVE OFFICER
- --------------------------------------               AND DIRECTOR
         Jack E. McGregor                    (PRINCIPAL EXECUTIVE OFFICER)


           Janet Hansen*                  SENIOR VICE PRESIDENT, CHIEF
- --------------------------------------      FINANCIAL OFFICER AND TREASURER
          Janet M. Hansen                  (PRINCIPAL FINANCIAL AND ACCOUNTING
                                                       OFFICER)


       George W. Edwards, Jr.*            DIRECTOR
- --------------------------------------
       George W. Edwards, Jr.


        Geoffrey Etherington*             DIRECTOR
- --------------------------------------
        Geoffrey Etherington


       Norwick R.G. Goodspeed*            DIRECTOR
- --------------------------------------
       Norwick R.G. Goodspeed

                                       4
<PAGE>
    
                                
- --------------------------------------    DIRECTOR
         Janet D. Greenwood


       Donald M. Halsted, Jr.*                   
- --------------------------------------    DIRECTOR 
       Donald M. Halsted, Jr.


          Eugene D. Jones*                          
- --------------------------------------    DIRECTOR 
          Eugene D. Jones


         Larry L. Pflieger*                        
- --------------------------------------    DIRECTOR 
         Larry L. Pflieger


        G. Jackson Ratcliffe*                     
- --------------------------------------    DIRECTOR 
        G. Jackson Ratcliffe


          John A. Urquhart*                         
- --------------------------------------    DIRECTOR 
          John A. Urquhart


- -------------------------------
* By signing her name hereto, Janet M. Hansen signs this Registration Statement
     as Senior Vice President, Chief Financial Officer and Treasurer of the
     Registrant and on behalf of the persons indicated above pursuant to the
     power of attorney duly executed by such persons and filed herewith.



                                              Janet M. Hansen
                              ------------------------------------------------
                                     (Janet M. Hansen, Attorney-in-Fact)



                                       5

<PAGE>
 
                                 EXHIBIT INDEX
 
 
EXHIBIT NUMBER                         DESCRIPTION OF EXHIBIT

 
     4.1        Aquarion Company Stock Incentive Plan - incorporated by
                reference

     4.2        Aquarion Company Directors' Deferred Compensation Plan -
                incorporated by reference

     4.3        Aquarion Company Long-Term Incentive Plan
 
     5          Opinion of Wiggin & Dana

     23.1       Consent of Price Waterhouse

     23.2       Consent of Wiggin & Dana (included in the opinion filed 
                as Exhibit 5)

     24         Power of Attorney

                                       6
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 15367}]
{"company-data": {"conformed-name": "AQUARION CO", "cik": "0000049423", "assigned-sic": "4941", "irs-number": "060852232", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "033-53473", "film-number": "94526019"}, "business-address": {"street1": "835 MAIN ST", "city": "BRIDGEPORT", "state": "CT", "zip": "06601", "phone": "2033366621"}, "mail-address": {"street1": "835 MAIN STREET", "city": "BRIDGEPORT", "state": "CT", "zip": "06601"}, "former-company": [{"former-conformed-name": "HYDRAULIC CO", "date-changed": "19910505"}, {"former-conformed-name": "BRIDGEPORT HYDRAULIC CO", "date-changed": "19700522"}]}
REGISTRATION NO. 33-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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

                                    Form S-8
                             REGISTRATION STATEMENT
                                     under
                           THE SECURITIES ACT OF 1933

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

                                Aquarion Company
             (Exact name of Registrant as specified in its charter)

Delaware                                                   06-0852232
(State or other jurisdiction of                            (I.R.S. Employer
incorporation or organization)                            Identification Number)

                                835 Main Street
                              Bridgeport, CT 06601
   (Address, including zip code, of Registrant's principal executive office)

                     Aquarion Company Stock Incentive Plan
             Aquarion Company Directors' Deferred Compensation Plan
                   Aquarion Company Long-Term Incentive Plan
                           (Full title of the Plans)

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

                                Janet M. Hansen
          Senior Vice President, Chief Financial Officer and Treasurer
                                Aquarion Company
                                835 Main Street
                              Bridgeport, CT 06601
                                 (203) 335-2333
(Name, address and telephone number, including area code, of agent for service)

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

                                   Copies to:
                             Joel S. Hoffman, Esq.
                           Simpson Thacher & Bartlett
                              425 Lexington Avenue
                            New York, New York 10017

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

                        CALCULATION OF REGISTRATION FEE
=======================================================================================================
                                                             PROPOSED        PROPOSED   
            TITLE OF                                         MAXIMUM         MAXIMUM         AMOUNT OF   
         SECURITIES TO                AMOUNT TO          OFFERING PRICE     AGGREGATE      REGISTRATION  
         BE REGISTERED              BE REGISTERED         PER SHARE(2)    OFFERING PRICE      FEE(2)      
- --------------------------------------------------------------------------------------------------------
Common Stock without par value       1,200,000 shares(1)     $24.6875        $29,625,000     $10,215
========================================================================================================
(1)  This Registration Statement also pertains to Series A Junior Participating
     Preferred Stock Purchase Rights ("Rights") of the Registrant.  Until the
     occurrence of certain prescribed events, the Rights are not exercisable,
     will be evidenced by the certificates for the Common Stock and will be
     transferred along with and only with the Common Stock.
(2)  Estimated solely for calculating the registration fee and calculated
     pursuant to Rule 457(c), based on the average of the high and low sale
     prices of the Common Stock on April 28, 1994 as reported on the New York
     Stock Exchange Composite Tape.

================================================================================
PART II
               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.

   The following documents filed with the Securities and Exchange Commission by
Aquarion Company (the "Company") are hereby incorporated in this Registration
Statement by reference:

    (a) The Company's Annual Report on Form 10-K for the fiscal year ended
    December 31, 1993.

   All documents filed by the Company pursuant to Sections 13(a), 13(c), 14 and
15(d) of the Exchange Act after the date of this Registration Statement and
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which 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 filing such
documents. Any statement contained in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any other subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
statement. Any such statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part of this Registration
Statement.

ITEM 4.  DESCRIPTION OF SECURITIES.

   Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.

   The financial statements incorporated in this Prospectus by reference to the
Annual Report on Form 10-K of Aquarion Company for the year ended December 31,
1993, have been so incorporated in reliance on the report of Price Waterhouse,
independent accountants, given on the authority of said firm as experts in
auditing and accounting.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

   The Company's Restated Certificate of Incorporation includes provisions which
have the purpose of limiting the personal liability of its directors for
monetary damages for breach of their duty of care to the full extent permissible
under Delaware law.

    The Delaware General Corporation Law authorizes a corporation's Board of
Directors to grant indemnity to officers and directors for certain liabilities,
including reimbursement of expenses incurred, arising under the Securities Act
of 1933, as amended (the "Securities Act").  Article VIII of the Company's By-
laws provides for indemnification of its officers, directors, employees and
other agents to the maximum extent permitted by Delaware law.

    The Company has purchased directors' and officers' liability insurance
covering certain liabilities incurred by its directors in connection with the
performance of their duties.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

   Not applicable

ITEM 8.  EXHIBITS.

   4.1 Aquarion Company Stock Incentive Plan - incorporated by reference to
       Exhibit A to the Company's Proxy Statement for its Annual Meeting held on
       April 26, 1994

   4.2 Aquarion Company Directors' Deferred Compensation Plan - incorporated by
       reference to Exhibit B to the Company's Proxy Statement for its Annual
       Meeting held on April 26, 1994

                                       2
4.3  Aquarion Company Long-Term Incentive Plan*

   5    Opinion of Wiggin & Dana*

   23.1 Consent of Price Waterhouse*

   23.2 Consent of Wiggin & Dana (included in the opinion filed as Exhibit 5)*

   24   Power of Attorney*

- ----------------
*   Filed herewith

ITEM 9.  UNDERTAKINGS.

   (a) The undersigned Registrant 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 this 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 this
   Registration Statement;

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

provided, however, that the undertakings set forth in paragraphs (i) and (ii)
above 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 Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act
that are incorporated by reference in this Registration Statement.

   (2)  That, for the purpose 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.

   (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 undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, 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 this Registration Statement shall be deemed to be a
new registration statement relating to the securities offered herein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

  (h)  Insofar as indemnification for liabilities arising under the Securities
Act of 1933, as amended (the "Securities Act"), may be permitted to directors,
officers or controlling persons of the Registrant pursuant to the foregoing
provisions, or otherwise, the Registrant has been advised that in the opinion of
the Securities and Exchange Commission such indemnification is against public
policy as expressed in the Securities Act and is, therefore, unenforceable. In
the event that a claim for indemnification against such liabilities (other than
the payment by the Registrant of expenses incurred or paid by a director,
officer or controlling person of the Registrant in the successful defense of any
action, suit or proceeding) is asserted against the Registrant by such director,
officer or controlling person in connection with the securities being
registered, the Registrant 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 policy
as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                       3
SIGNATURES

   Pursuant to the requirements of the Securities Act of 1933, Aquarion Company
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 Bridgeport, State of Connecticut, on this 4th, day of
May, 1994.

                              AQUARION COMPANY

                              By         Janet M. Hansen 
                                ----------------------------------------
                                         Janet M. Hansen
                                      Senior Vice President,                
                                     Chief Financial Officer and
                                             Treasurer

  Pursuant to the requirements of the Securities Act of 1933, this Registration
Statement has been signed by the following persons in the capacities indicated
on this 4th day of May, 1994.

         William S. Warner*               CHAIRMAN OF THE BOARD OF DIRECTORS
- --------------------------------------               AND DIRECTOR
         William S. Warner

         Jack E. McGregor*                PRESIDENT, CHIEF EXECUTIVE OFFICER
- --------------------------------------               AND DIRECTOR
         Jack E. McGregor                    (PRINCIPAL EXECUTIVE OFFICER)

           Janet Hansen*                  SENIOR VICE PRESIDENT, CHIEF
- --------------------------------------      FINANCIAL OFFICER AND TREASURER
          Janet M. Hansen                  (PRINCIPAL FINANCIAL AND ACCOUNTING
                                                       OFFICER)

       George W. Edwards, Jr.*            DIRECTOR
- --------------------------------------
       George W. Edwards, Jr.

        Geoffrey Etherington*             DIRECTOR
- --------------------------------------
        Geoffrey Etherington

       Norwick R.G. Goodspeed*            DIRECTOR
- --------------------------------------
       Norwick R.G. Goodspeed

                                       4
- --------------------------------------    DIRECTOR
         Janet D. Greenwood

       Donald M. Halsted, Jr.*                   
- --------------------------------------    DIRECTOR 
       Donald M. Halsted, Jr.

          Eugene D. Jones*                          
- --------------------------------------    DIRECTOR 
          Eugene D. Jones

         Larry L. Pflieger*                        
- --------------------------------------    DIRECTOR 
         Larry L. Pflieger

        G. Jackson Ratcliffe*                     
- --------------------------------------    DIRECTOR 
        G. Jackson Ratcliffe

          John A. Urquhart*                         
- --------------------------------------    DIRECTOR 
          John A. Urquhart

- -------------------------------
* By signing her name hereto, Janet M. Hansen signs this Registration Statement
     as Senior Vice President, Chief Financial Officer and Treasurer of the
     Registrant and on behalf of the persons indicated above pursuant to the
     power of attorney duly executed by such persons and filed herewith.

                                              Janet M. Hansen
                              ------------------------------------------------
                                     (Janet M. Hansen, Attorney-in-Fact)

                                       5
EXHIBIT INDEX
 
 
EXHIBIT NUMBER                         DESCRIPTION OF EXHIBIT

 
     4.1        Aquarion Company Stock Incentive Plan - incorporated by
                reference

     4.2        Aquarion Company Directors' Deferred Compensation Plan -
                incorporated by reference

     4.3        Aquarion Company Long-Term Incentive Plan
 
     5          Opinion of Wiggin & Dana

     23.1       Consent of Price Waterhouse

     23.2       Consent of Wiggin & Dana (included in the opinion filed 
                as Exhibit 5)

     24         Power of Attorney

                                       6