Property, Plant, and Equipment

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment [Abstract]

8. PROPERTY, PLANT, AND EQUIPMENT

A summary of the historical cost of property, plant, and equipment is as follows:




thousands	Estimated Useful Life	September 30, 2023		December 31, 2022
Land	N/A	$	11,383	$	10,982
Gathering systems – pipelines	30 years	5,447,406		5,519,592
Gathering systems – compressors	15 years	2,369,219		2,266,410
Processing complexes and treating facilities	25 years	3,452,289		3,419,201
Transportation pipeline and equipment	3 to 48 years	192,289		174,241
Produced-water disposal systems	20 years	1,063,184		932,627
Assets under construction	N/A	443,272		263,353
Other	3 to 40 years	830,038		779,187
Total property, plant, and equipment		13,809,080		13,365,593
Less accumulated depreciation		5,144,678		4,823,993
Net property, plant, and equipment		$	8,664,402	$	8,541,600

“Assets under construction” represents property that is not yet placed into productive service as of the respective balance sheet date and is excluded from capitalized costs being depreciated.

Long-lived asset impairments. During the nine months ended September 30, 2023, the Partnership recognized a long-lived asset impairment of $52.1 million for assets located in the Rockies due to a reduction in estimated future cash flows resulting from a contract termination notice received in the first quarter of 2023. This asset was impaired to its estimated fair value of $22.8 million. The fair value was measured using the income approach and Level-3 fair value inputs. The income approach was based on the Partnership’s projected future earnings before interest, taxes, depreciation, and amortization (“EBITDA”) and free cash flows, which requires significant assumptions including, among others, future throughput volumes based on current expectations of producer activity and operating costs.