The Company evaluates goodwill for impairment annually during the fourth quarter and whenever events or changes in circumstances indicate it is more likely than not that the fair value of a reporting unit with goodwill is less than its carrying amount. Significant assumptions used to estimate the reporting units’ fair value include the discount rate as well as estimates of future cash flows, which are impacted primarily by commodity prices and producer customers’ development plans (which impact volumes and capital requirements).

During the third quarter of 2019, the Company performed an interim impairment analysis of the goodwill related to the wastewater treatment reporting unit recorded in connection with the Transactions due to the Company’s strategic evaluation of the Clearwater Facility. As a result of this evaluation, the Company incurred impairment charges to the goodwill and customer relationships intangible asset associated with the Clearwater Facility, which is in the water handling segment. See Note 4—Clearwater Facility Impairment.

The Company performed its annual goodwill impairment test in the fourth quarter of 2019. As a result of this test, the Company incurred impairment charges of $298 million to its fresh water delivery and services reporting unit, which is in the water handling segment. This was primarily due to decreased water volumes driven by decreased drilling and increased use of water blending operations by Antero Resources.

The changes in the carrying amount in goodwill for the year ended December 31, 2019 were as follows (in thousands):

(1)

See Note 3—Business Combination.

All customer relationships are subject to amortization and will be amortized over a weighted-average period of 23 years. The changes in the carrying amount of customer relationships for the year ended December 31, 2019 were as follows (in thousands):


Customer relationships as of December 31, 2018	$	—
Customer relationships acquired⁽¹⁾		1,567,000
Accumulated amortization		(57,010)
Impairment		(11,871)
Customer relationships as of December 31, 2019	$	1,498,119

(1)

See Note 3—Business Combination.

Future amortization expense is as follows (in thousands):


Year ending December 31, 2020	$	70,672
Year ending December 31, 2021		70,672
Year ending December 31, 2022		70,672
Year ending December 31, 2023		70,672
Year ending December 31, 2024		70,672
Thereafter		1,144,759
Total	$	1,498,119