Exhibit 10.37b
                         FIRST AMENDING AGREEMENT TO THE
                         KEYSPAN ENERGY DEVELOPMENT CO.
                   CREDIT AGREEMENT DATED AS OF JULY 29, 1999

                                     AMONG:

                         KEYSPAN ENERGY DEVELOPMENT CO.

                                   as Borrower

                                     - and -

                              ROYAL BANK OF CANADA,
                       THE CHASE MANHATTAN BANK OF CANADA,
                                BANK OF MONTREAL,
                                 BANK ONE CANADA
                          AND ALBERTA TREASURY BRANCHES

                                   as Lenders

                                     - and -

                              ROYAL BANK OF CANADA

                             as Administrative Agent






                                October 13, 2000





<PAGE>






         THIS FIRST AMENDING AGREEMENT dated as of the 13th day of October, 2000

AMONG:

          KEYSPAN  ENERGY  DEVELOPMENT  CO., a Nova Scotia  unlimited  liability
          company (hereinafter referred to as the "Borrower")

                                                              OF THE FIRST PART

                                     - and -

          ROYAL  BANK OF CANADA,  THE CHASE  MANHATTAN  BANK OF CANADA,  BANK OF
          MONTREAL,  BANK ONE CANADA AND ALBERTA TREASURY BRANCHES  (hereinafter
          sometimes collectively referred to as the "Lenders")

                                                              OF THE SECOND PART

                                     - and -

          ROYAL  BANK OF  CANADA,  a Canadian  chartered  bank,  as agent of the
          Lenders  hereunder  (hereinafter  referred  to as the  "Administrative
          Agent")

                                                               OF THE THIRD PART

         WHEREAS Keyspan Energy Development Co. as Borrower, Royal Bank of
Canada, The Chase Manhattan Bank of Canada, The Toronto-Dominion Bank, Bank of
Montreal, Bank One Canada, Alberta Treasury Branches and National Bank of Canada
as Lenders and Royal Bank of Canada as Administrative Agent entered into a
credit agreement dated as of July 29, 1999;

         AND WHEREAS the Borrower has requested that the Lenders consent to the
Borrower incurring indebtedness of up to Cdn. $125,000,000 for purposes of
financing the purchase of Gulf Canada Resources Limited's remaining interest in
the Gulf Midstream assets and to finance the acquisition, constitution and
expansion of gas processing and gathering assets;

         AND WHEREAS the Lenders have required that the Borrower, the Lenders
and the Administrative Agent enter into this First Amending Agreement as one of
the conditions to the Lenders providing their consent to the Borrower incurring
that indebtedness;

         AND WHEREAS the Borrower, the Administrative Agent and the Lenders wish
to enter into this First Amending Agreement to set forth the changes to the
Credit Agreement, and to otherwise confirm the provisions of Amended Credit
Agreement;

         NOW THEREFORE THIS AGREEMENT WITNESSES that in consideration of the
covenants and agreements herein contained and other good and valuable
consideration, the receipt and sufficiency of which is hereby conclusively
acknowledged by each of the parties hereto, the parties hereto covenant and
agree as follows:

1.       Definitions

         All capitalized terms used in this First Amending Agreement shall,
unless otherwise defined herein, have the meanings herein given to them in the
Credit Agreement, and:

         "Amended Credit Agreement" means the Credit Agreement, as amended by
         this First Amending Agreement, and as it may hereafter be further
         amended from time to time.

         "Credit Agreement" means the credit agreement dated as of July 29, 1999
         among Keyspan Energy Development Co. as Borrower, Royal Bank of Canada
         and the other financial institutions named therein from time to time as
         Lenders and Royal Bank of Canada as Administrative Agent.

         "First Amending Agreement" means this first amending agreement.

2.       Amendments to Credit Agreement

         Effective as of the date of this First Amending Agreement, the Credit
Agreement is amended as follows:

               (a)  Section 8.1(n) of the Credit  Agreement is hereby deleted in
                    its entirety and replaced with the following:

                    Debt - The Borrower has no  indebtedness  for borrowed money
                    except (i) the amount of $100,511,840  plus interest accrued
                    thereon since April 27, 1999 owing to KS Finance pursuant to
                    the  KS  Finance  Loan,  (ii)  indebtedness  of up  to  Cdn.
                    $125,000,000  pursuant to the credit  agreement  dated as of
                    October 13, 2000 among the  Borrower  as  Borrower,  Bank of
                    Montreal and the other financial  institutions named therein
                    from time to time as lenders  and Bank of  Montreal as agent
                    for those lenders,  and (iii) other  indebtedness  permitted
                    hereunder or  consented to in writing by the  Administrative
                    Agent.

               (b)  Section 9.2(g) of the Credit  Agreement is hereby deleted in
                    its entirety.

               (c)  Schedule "A" to the Credit  Agreement  is hereby  deleted in
                    its entirety and  replaced  with  Schedule "A" to this First
                    Amending Agreement.

3.       Representations and Warranties

         The Borrower hereby represents and warrants to the Lenders that the
applicable representations and warranties contained in Section 8.1 of the Credit
Agreement, as amended by this First Amending Agreement, are true and accurate in
all material respects as if made on the date of this First Amending Agreement.

4.       Confirmation

         Each of the parties hereto acknowledges and agrees that the Credit
Agreement, as amended by this First Amending Agreement, and all other Documents
are and will continue to be in full force and effect, and are hereby ratified
and confirmed, and the rights and obligations of all parties thereunder will not
be affected in any manner by the provisions of this First Amending Agreement,
except as expressly provided in Section 2 of this First Amending Agreement.

5.       Further Assurances

         The Borrower will from time to time forthwith, and at the Borrower's
own cost and expense, do, make, execute and deliver, or cause to be done, made,
executed and delivered, all such further documents, financing statements,
assignments, acts, manners and things which may be reasonably required by the
Administrative Agent and are consistent with the intention of the parties hereto
as evidenced herein, with respect to all matters arising under this First
Amending Agreement or the Amended Credit Agreement.

6.       Expenses

         Without in any way limiting the provisions of Section 12.1 of the
Credit Agreement, the Borrower will be liable for all reasonable expenses of the
Administrative Agent and the Lenders, including legal fees and other
out-of-pocket expenses, in connection with the negotiation, preparation,
execution and delivery of this First Amending Agreement.



<PAGE>



7.      Counterparts

         This First Amending Agreement may be executed in any number of
counterparts, each of which when executed and delivered will be deemed to be an
original, and all of which when taken together shall constitute one and the same
instrument.

         IN WITNESS WHEREOF the parties hereto have caused this First Amending
Agreement to be duly executed by their respective authorized officers as of the
date and year first above written.

                          KEYSPAN ENERGY DEVELOPMENT CO., as Borrower

                          Per:
                              --------------------------------------------------
                              Name:
                              Title:


                           Per:
                               -------------------------------------------------
                               Name:
                               Title:


                          ROYAL BANK OF CANADA,
                          in its capacity as
                          Administrative Agent

                          Per:
                              --------------------------------------------------
                              Name:
                              Title:

                          Per:
                                ------------------------------------------------
                               Name:
                               Title:


<PAGE>



                                ROYAL BANK OF CANADA, as a Lender

                                Per:
                                    -----------------------------------------
                                    Name:
                                    Title:

                                 Per:
                                    -----------------------------------------
                                    Name:
                                    Title:















This page is attached to and forms part of a First Amending Agreement dated as
of October 13, 2000 among Keyspan Energy Development Co. as Borrower, Royal Bank
of Canada, The Chase Manhattan Bank of Canada, Bank of Montreal, Bank One Canada
and Alberta Treasury Branches as Lenders and Royal Bank of Canada as
Administrative Agent.



<PAGE>





                           THE CHASE MANHATTAN BANK OF CANADA, as a Lender

                            Per:
                                  ----------------------------------------------
                                  Name:
                                  Title:

                            Per:
                                  ----------------------------------------------
                                  Name:
                                  Title:












 This page is attached to and forms part of a First Amending Agreement dated as
of October 13, 2000 among Keyspan Energy Development Co. as Borrower, Royal Bank
of Canada, The Chase Manhattan Bank of Canada, Bank of Montreal, Bank One Canada
and Alberta Treasury Branches as Lenders and Royal Bank of Canada as
Administrative Agent.


<PAGE>




                          BANK OF MONTREAL, as a Lender

                          Per:
                              --------------------------------------------------
                              Name:
                              Title:

                          Per:
                              --------------------------------------------------
                              Name:
                              Title:











This page is attached to and forms part of a First Amending Agreement dated as
of October 13, 2000 among Keyspan Energy Development Co. as Borrower, Royal Bank
of Canada, The Chase Manhattan Bank of Canada, Bank of Montreal, Bank One Canada
and Alberta Treasury Branches as Lenders and Royal Bank of Canada as
Administrative Agent.


<PAGE>




                                BANK ONE CANADA, as a Lender

                                Per:
                                    --------------------------------------------
                                    Name:
                                    Title:

                                Per:
                                    --------------------------------------------
                                    Name:
                                    Title:










This page is attached to and forms part of a First Amending Agreement dated as
of October 13, 2000 among Keyspan Energy Development Co. as Borrower, Royal Bank
of Canada, The Chase Manhattan Bank of Canada, Bank of Montreal, Bank One Canada
and Alberta Treasury Branches as Lenders and Royal Bank of Canada as
Administrative Agent.






<PAGE>




                                ALBERTA TREASURY BRANCHES, as a
                                Lender

                                Per:
                                    --------------------------------------------
                                    Name:
                                    Title:

                                 Per:
                                     -------------------------------------------
                                     Name:
                                     Title:


This page is attached to and forms part of a First Amending Agreement dated as
of October 13, 2000 among Keyspan Energy Development Co. as Borrower, Royal Bank
of Canada, The Chase Manhattan Bank of Canada, Bank of Montreal, Bank One Canada
and Alberta Treasury Branches as Lenders and Royal Bank of Canada as
Administrative Agent.



<PAGE>



                                   SCHEDULE A

Schedule A to the Credit  Agreement  dated July 29,  1999 among  Keyspan  Energy
Development  Co. as  Borrower  and a syndicate  of  Lenders,  with Royal Bank of
Canada as Administrative Agent

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

                             LENDERS AND COMMITMENTS


Lender, Address and Fax                                            Commitment
-----------------------                                            ----------

Royal Bank of Canada                                            Cdn. $60,000,000
23rd Floor, 335 - 8th Avenue S.W.
Calgary, Alberta
T2P 2N5


Attention:               Account Manager
Telecopier No.:          (403) 292-3234

The Chase Manhattan Bank of Canada                              Cdn. $35,000,000
1 First Canadian Place
100 King Street West
Suite 6900, P.O. Box 106
Toronto, Ontario
M5X 1A4


Attention:               Vice President
Telecopier No.:          (416) 216-4132

with a copy to:
Chase Manhattan Bank
4 MetroTech Centre, 22nd Floor
Brooklyn, New York
11245


Attention:               Vice President
Telecopier No.:          (212) 552-1637

Bank of Montreal                                                Cdn. $50,000,000
1400, 421 - 7th Avenue S.W.
Calgary, Alberta
T2P 4K9


Attention:               Director, Corporate Accounts
Telecopier No.:          (403) 515-3650

Bank One Canada                                                 Cdn. $35,000,000
c/o Bank One NA
One First National Plaza
Suite 0363
Chicago, Illinois
60670


Attention:               Relationship Manager
Telecopier No.:          (312) 732-3055

Alberta Treasury Branches                                       Cdn. $20,000,000
ATB Place
9888 Jasper Avenue
Edmonton, Alberta
T5J 1P1


Attention:               Senior Credit Manager
Telecopier No.:          (780) 408-7262