DECLARATION OF TRUST
                                          
                                          
          This DECLARATION OF TRUST, dated as of February 27, 1998 (this
"Declaration"), among Public Service Company of Colorado, a Colorado
corporation, as "Depositor," and The Bank of New York, a New York banking
corporation, The Bank of New York (Delaware), a Delaware banking corporation,
and Nancy Felker, not in their individual capacities but solely as trustees (the
"Trustees"). The Depositor and the Trustees hereby agree as follows: 

          1. The trust created hereby shall be known as "PSCO Capital Trust I,"
in which name the Trustees, or the Depositor to the extent provided herein, may
conduct the business of the Trust, make and execute contracts, and sue and be
sued.

          2. The Depositor hereby assigns, transfers, conveys and sets over to
the Trustees the sum of $10. The Trustees hereby acknowledge receipt of such
amount in trust from the Depositor, which amount shall constitute the initial
trust estate. The Trustees hereby declare that they will hold the trust estate
in trust for the Depositor. It is the intention of the parties hereto that the
Trust created hereby constitute a business trust under Chapter 38 of Title 12 of
the Delaware Code, 12 DEL. C. ss. 3801, et seq. (the "Business Trust Act"), and
that this document constitutes the governing instrument of the Trust. The
Trustees are hereby authorized and directed to execute and file a certificate of
trust with the Delaware Secretary of State in accordance with the provisions of
the Business Trust Act.

          3. The Depositor and the Trustees will enter into an amended and
restated Declaration of Trust, satisfactory to each such party and substantially
in the form included as an exhibit to the 1933 Act Registration Statement (as
defined below), to provide for the contemplated operation of the Trust created
hereby and the issuance of the Preferred Securities and Common Securities
referred to therein.  Prior to the execution and delivery of such amended and
restated Declaration of Trust, the Trustees shall not have any duty or
obligation hereunder or with respect to the trust estate, except as otherwise
required by applicable law or as may be necessary to obtain prior to such
execution and delivery of any licenses, consents or approvals required by
applicable law or otherwise.

          4. The Depositor and the Trustees hereby authorize and direct the
Depositor, as the sponsor of the Trust, (i) to file with the Securities and
Exchange Commission (the "Commission") and execute, in each case on behalf of
the Trust, (a) the Registration Statement on Form S-3 (the "1933 Act
Registration Statement"), including any pre-effective or post-effective
amendments to the 1933 Act Registration Statement (including the prospectus,
prospectus supplements and the exhibits contained therein), relating to the
registration under the Securities Act of 1933, as amended, of the Preferred
Securities of the Trust and possibly certain other 



securities and (b) a Registration Statement on Form 8-A (the "1934 Act 
Registration Statement") (including all pre-effective and post-effective 
amendments thereto) relating to the registration of the Preferred Securities 
of the Trust under Section 12(b) or 12(g) of the Securities Exchange Act of 
1934, as amended, including any amendments thereto; (ii) to file with the New 
York Stock Exchange or any other national stock exchange or The Nasdaq 
National Market (each, an "Exchange") and execute on behalf of the Trust one 
or more listing applications and all other applications, statements, 
certificates, agreements and other instruments as shall be necessary or 
desirable to cause the Preferred Securities to be listed on any of the 
Exchanges; (iii) to file and execute on behalf of the Trust such 
applications, reports, surety bonds, irrevocable consents, appointments of 
attorney for service of process and other papers and documents as shall be 
necessary or desirable to register the Preferred Securities under the 
securities or blue sky laws of such jurisdictions as the Depositor, on behalf 
of the Trust, may deem necessary or desirable and (iv) to negotiate the terms 
of and to execute, deliver and perform on behalf of the Trust that certain 
Underwriting Agreement relating to the Preferred Securities, including the 
Pricing Agreement attached as an exhibit thereto, if any, in each case among 
the Trust, the Depositor and the several Underwriters named therein, 
substantially in the form included as an exhibit to the 1933 Act Registration 
Statement. In the event that any filing referred to in clauses (i), (ii) and 
(iii) above is required by the rules and regulations of the Commission, an 
Exchange or state securities or blue sky laws, to be executed on behalf of 
the Trust by any of the Trustees, Nancy Felker, in her capacity as a Trustee 
of the Trust, is hereby authorized and directed to join in any such filing 
and to execute on behalf of the Trust any and all of the foregoing. In 
connection with all of the foregoing, the Depositor hereby constitutes and 
appoints James D. Steinhilper as its true and lawful attorney-in-fact and 
agent, with full power of substitution and resubstitution, for the Depositor 
or in the Depositor's name, place and stead, in any and all capacities, to 
sign any and all amendments (including post-effective amendments) to the 1933 
Act Registration Statement and the 1934 Act Registration Statement and to 
file the same, with all exhibits thereto, and other documents in connection 
therewith, with the Commission, granting unto 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 connection therewith, as fully to all 
intents and purposes as the Depositor might or could do in person, hereby 
ratifying and confirming all that said attorney-in-fact and agent or his 
substitute or substitutes, shall do or cause to be done by virtue hereof. 

          5. This Declaration may be executed in one or more counterparts.

          6. The number of Trustees initially shall be three (3) and thereafter
the number of Trustees shall be such number as shall be fixed from time to time
by a written instrument signed by the Depositor which may increase or decrease
the number of Trustees; provided, however, that to the extent required by the
Business Trust Act, one Trustee shall either be a natural person who is a
resident of the State of Delaware or, if not a natural person, an entity which
has its principal place of business in the State of Delaware and otherwise meets
the requirements of applicable Delaware law. Subject to the foregoing, the
Depositor is entitled to appoint or remove without cause any Trustee at any
time.  Any Trustee may resign upon thirty (30) days' prior notice to the
Depositor.

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          7. This Declaration shall be governed by, and construed in accordance
with, the laws of the State of Delaware (without regard to conflict of laws of
principles).

     IN WITNESS WHEREOF, the parties hereto have caused this Declaration to be
duly executed as of the day and year first above written. 

                         PUBLIC SERVICE COMPANY OF 
                         COLORADO, as Depositor 


                         By:  /s/ James D. Steinhilper  
                              -----------------------------------------------
                         Name:     James D. Steinhilper
                         Title:    Treasurer and Director of Finance

                         THE BANK OF NEW YORK, not in its individual capacity
                         but solely as Trustee

                         By:  /s/ Walter N. Gitlin                           
                              -----------------------------------------------
                         Name:     Walter N. Gitlin
                         Title:    Vice President

                         THE BANK OF NEW YORK (DELAWARE), not in its 
                         individual capacity but solely as Trustee

                         By: /s/ Walter N. Gitlin                            
                              -----------------------------------------------
                         Name:     Walter N. Gitlin
                         Title:    Authorized Signatory

                         /s/ Nancy Felker 
                         ----------------------------------------------------
                         Nancy Felker, not in her individual capacity but 
                         solely as Trustee


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