April 17, 2002



Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549

Ladies and Gentlemen:

Arthur Andersen LLP, our independent public accountants, has represented to us
that their audit of the financial statements of KeySpan Corporation, included in
the Company's Annual Report on Form 10-K for the year ended December 31, 2001,
was subject to Arthur Andersen's quality control system for the U.S. accounting
and auditing practice to provide reasonable assurance that the engagement was
conducted in compliance with professional standards; and that there was
appropriate continuity of Arthur Andersen personnel working on the audit and
availability of national office consultation. The availability of personnel at
foreign affiliates of Arthur Andersen to conduct the relevant portions of the
audit is not relevant to this audit.


                                                      Sincerely,

                                                      /s/Gerald Luterman

                                                      Gerald Luterman
                                                      Executive Vice President &
                                                      Chief Financial Officer