Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

We provide for depreciation under the composite (group) method using the straight-line method at FERC prescribed rates that are applied to the cost of the group for transmission facilities, production and gathering facilities and storage facilities. Under this method, assets with similar lives and characteristics are grouped and depreciated as one asset. Included in our depreciation rates is a negative salvage component (net cost of removal) that we currently collect in rates. Our depreciation rates are subject to change each time we file a general rate case with the FERC. Depreciation rates used for major regulated gas plant facilities at December 31, 2021, 2020 and 2019 are as follows:


Category of Property						Depreciation Rate
Gathering facilities						0% - 1.00%
Storage facilities						1.86% - 2.05%
Onshore transmission facilities						2.50% - 7.13%
Offshore transmission facilities						1.25%