40-F/A

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U.S. Securities and Exchange Commission
Washington, D.C. 20549
Form 40-F/A
Amendment No. 1

o	REGISTRATION STATEMENT PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT of 1934
OR
ý	ANNUAL REPORT PURSUANT TO SECTION 13(a) OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2007

Commission File Number 1-8887

TRANSCANADA PIPELINES LIMITED
(Exact Name of Registrant as specified in its charter)

Canada
(Jurisdiction of incorporation or organization)

4922, 4923, 4924, 5172
(Primary Standard Industrial Classification Code Number (if applicable))

Not Applicable
(I.R.S. Employer Identification Number (if applicable))

TransCanada Tower, 450 - 1 Street S.W.
Calgary, Alberta, Canada, T2P 5H1
(403) 920-2000
(Address and telephone number of Registrant's principal executive offices)

CT Corporation, Suite 2610, 520 Pike Street
Seattle, Washington, 98101; (206) 622-4511; (800) 456-4511
(Name, address (including zip code) and telephone number (including area code)
of agent for service in the United States)

Securities registered pursuant to section 12(b) of the Act: None
Securities registered pursuant to Section 12(g) of the Act: None
Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act: None

For annual reports, indicate by check mark the information filed with this Form:

ý Annual Information Form ý Audited annual financial statements

Indicate the number of outstanding shares of each of the issuer's classes of capital or common stock as of the close of the period covered by the annual report.

At December 31, 2007, 4,000,000 Cumulative Redeemable First Preferred Shares Series U
and 4,000,000 Cumulative Redeemable First Preferred Shares Series Y
were issued and outstanding
All of the Registrant's common shares are owned by TransCanada Corporation.

Indicate by check mark whether the Registrant by filing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934 (the "Exchange Act"). If "Yes" is marked, indicate the file number assigned to the Registrant in connection with such Rule.

Yes o No ý

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act during the preceding 12 months (or such shorter period that the Registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.

Yes ý No o

EXPLANATORY NOTE

        TransCanada PipeLines Limited ("TCPL") is filing this Form 40-F/A Amendment No. 1 to its Annual Report on Form 40-F for the year ended December 31, 2007 which was filed with the Securities and Exchange Commission on February 28, 2008, to re-file and correct an error made in the legending of the map which forms part of the cover of the TCPL 2007 Management's Discussion and Analysis and Audited Consolidated Financial Statements. This corrected page is not incorporated herein by reference and shall be deemed not filed with the U.S. Securities and Exchange Commission (the "Commission") as part of this Report under the Exchange Act.

        Other than as expressly set forth above, this Form 40-F/A does not, and does not purport to, update, or restate the information in any Item of the Form 40-F or reflect any events that have occurred after the Form 40-F was filed.

UNDERTAKING

        The Registrant undertakes to make available, in person or by telephone, representatives to respond to inquiries made by the staff of the Commission, and to furnish promptly, when requested to do so by the Commission staff, information relating to: the securities registered pursuant to Form 40-F; the securities in relation to which the obligation to file an Annual Report on Form 40-F arises; or transactions in said securities.

FORWARD-LOOKING INFORMATION

        This document, the documents incorporated by reference, and other reports and filings made with the securities regulatory authorities may contain certain information that is forward-looking and is subject to important risks and uncertainties. The words "anticipate", "expect", "believe", "may", "should", "estimate", "project", "outlook", "forecast" or other similar words are used to identify such forward looking information. All forward looking statements reflect TCPL's beliefs and assumptions based on information available at the time the statements were made. Actual results or events may differ from those predicted in these forward-looking statements. Factors that could cause actual results or events to differ materially from current expectations include, among other things, the ability of TCPL to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the operating performance of the Company's natural gas pipeline and energy assets, the availability and price of energy commodities, regulatory processes and decisions, changes in environmental and other laws and regulations, competitive factors in the natural gas pipeline and energy industry sectors, construction and completion of capital projects, labour, equipment and material costs, access to capital markets, interest and currency exchange rates, technological developments and the current economic conditions in North America. By its nature, forward-looking information is subject to various risks and uncertainties, which could cause TCPL's actual results and experience to differ materially from the anticipated results or other expectations expressed. The Company's material risks and assumptions are discussed further in TCPL's Management's Discussion and Analysis filed as document 13.2 hereto including the headings "Pipelines — Opportunities and Developments", "Pipelines-Business Risks", "Energy — Opportunities and Developments", "Energy — Business Risks" and "Risk Management and Financial Instruments". Additional information on these and other factors is available in the reports filed by TCPL with Canadian securities regulators and with the U.S. Securities and Exchange Commission ("SEC"). Readers are cautioned not to place undue reliance on this forward-looking information, which is given as of the date it is expressed in this document or otherwise, and to not use future-oriented information or financial outlooks for anything other than their intended purpose. TCPL undertakes no obligation to update publicly or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as required by law.

SIGNATURES

        Pursuant to the requirements of the Exchange Act, the Registrant certifies that it meets all of the requirements for filing on Form 40-F/A and has duly caused this amendment to the Annual Report to be signed on its behalf by the undersigned, thereto duly authorized, in the City of Calgary, Province of Alberta, Canada.

		TRANSCANADA PIPELINES LIMITED
	Per:	/s/ DONALD J. DEGRANDISDONALD J. DEGRANDIS Corporate Secretary
Date: March 3, 2008

EXHIBITS

31.1	Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2	Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

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EXPLANATORY NOTE
UNDERTAKING
FORWARD-LOOKING INFORMATION
SIGNATURES

EX-31.1

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Exhibit 31.1

Certifications

I, Harold N. Kvisle, certify that:

1.

I have reviewed this annual report on Form 40-F/A of TransCanada PipeLines Limited;

2.

Based on my knowledge, this annual report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this annual report; and

3.

Based on my knowledge, the financial statements, and other financial information included in this annual report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this annual report.

Dated March 3, 2008
	/s/ Harold N. Kvisle Harold N. Kvisle President and Chief Executive Officer

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Exhibit 31.1

Certifications

EX-31.2

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Exhibit 31.2

Certifications

I, Gregory A. Lohnes, certify that:

1.

I have reviewed this annual report on Form 40-F/A of TransCanada PipeLines Limited;

2.

Based on my knowledge, this annual report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this annual report; and

3.

Based on my knowledge, the financial statements, and other financial information included in this annual report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this annual report.

Dated March 3, 2008
	/s/ Gregory A. Lohnes Gregory A. Lohnes Executive Vice-President and Chief Financial Officer

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Exhibit 31.2

Certifications