Property, Plant, and Equipment

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

9. PROPERTY, PLANT, AND EQUIPMENT

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


		December 31,
thousands	Estimated Useful Life	2024		2023

Land	N/A	$	13,041	$	12,504
Gathering systems – pipelines	30 years	5,848,865		5,890,607
Gathering systems – compressors	15 years	2,718,145		2,553,602
Processing complexes and treating facilities	25 years	4,046,670		3,745,332
Transportation pipeline and equipment	3 to 48 years	257,289		259,314
Produced-water disposal systems	20 years	1,198,742		1,098,616
Assets under construction	N/A	460,056		479,368
Other	3 to 40 years	967,102		906,088
Total property, plant, and equipment		15,509,910		14,945,431
Less accumulated depreciation		5,795,301		5,290,415
Net property, plant, and equipment		$	9,714,609	$	9,655,016

“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. “Other” property, plant, and equipment primarily represents asset retirement costs, measurement equipment, capitalized interest, electrical distribution equipment, and computer software and equipment.

Long-lived asset impairments. During the year ended December 31, 2023, the Partnership recognized a long-lived asset impairment of $52.1 million for assets located in the Rocky Mountains 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 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.