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Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

December 31 (millions of dollars)		2016	2015		2014		2013(a)		2012(a)
Earnings
	Net income before adjustment for income from equity investees	128	122		116		124		130
	Fixed charges	68	61		45		44		41
	Distributed income (loss) of equity investees(b)	116	(102	)	88		67		99
	Non-controlling interests of subsidiaries that have not incurred fixed charges	–	–		(10	)	(14	)	(13	)
Total Earnings		312	81		239		221		257
Fixed Charges
	Interest expensed and capitalized	66	60		44		43		40
	Amortization of other assets	2	1		1		1		1
Total Fixed Charges		68	61		45		44		41
Ratio of Earnings/Fixed Charges		4.59X	1.33x		5.31x		5.02x		6.27x

(a)

An additional 45 percent membership interests in each of GTN and Bison were acquired from subsidiaries of TransCanada in 2013 resulting in a 70 percent ownership in each. As a result, the acquisition was accounted for as a transaction between entities under common control, similar to a pooling of interests, whereby the assets and liabilities of GTN and Bison were recorded at TransCanada's carrying value and the Partnership's historical financial information was recast, except net income (loss) per common unit, to consolidate GTN and Bison for all periods presented.

(b)

Distributed income of equity investees for 2015 includes $199 million impairment charge on our Investment in Great Lakes.

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Exhibit 12.1

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES