SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Prior to May 28, 2019, the Partnership’s services were performed by the Predecessor. The consolidated financial statements include the results of the Predecessor for the periods presented prior to the closing of the IPO on May 28, 2019. The Predecessor financial statements have been prepared from the separate records maintained by the Partnership and may not necessarily be indicative of the actual results of operations that might have occurred if the Predecessor had been operated separately during the periods reported. The consolidated results of operations following the completion of the IPO are presented together with the results of operations pertaining to the Predecessor. The assets of the Predecessor consist of produced water disposal wells and related gathering systems, office buildings, surface land and an oil gathering system and asset retirement obligations related to these assets, which were contributed effective January 1, 2019. See Note 4—Acquisitions. The capital contribution of the net proceeds from the IPO to the Operating Company in exchange for 29% of the limited liability company units of the Operating Company was accounted for as a combination of entities under common control, with assets and liabilities transferred at their carrying amounts in a manner similar to a pooling of interests. The Partnership did not own any assets prior to May 28, 2019, the date of the equity contribution agreement by and between the Partnership and the Predecessor. Prior to the IPO, the Predecessor was a wholly owned subsidiary of Diamondback. For periods prior to May 28, 2019, the accompanying consolidated financial statements and related notes thereto represent the financial position, results of operations, cash flows and changes in members’ equity of the Predecessor and, for periods on and after May 28, 2019, the accompanying consolidated financial statements and related notes thereto represent the financial position, results of operations, cash flows and changes in unitholders’ equity of the Partnership and its partially owned subsidiary, the Operating Company. The Partnership’s operations are reported in two operating business segments: (i) midstream services and (ii) real estate operations. The consolidated financial statements include the accounts of the Partnership and its subsidiaries after all significant intercompany balances and transactions have been eliminated upon consolidation.
Reclassifications	Reclassifications Certain prior period amounts have been reclassified to conform to the current period financial statement presentation. These reclassifications had no effect on the previously reported total assets, total liabilities, unitholders’ equity, results of operations or cash flows.
Use of Estimates	Use of Estimates Certain amounts included in or affecting the Partnership’s financial statements and related notes must be estimated by management, requiring certain assumptions to be made with respect to values or conditions that cannot be known with certainty at the time the financial statements are prepared. These estimates and assumptions affect the amounts the Partnership reports for assets and liabilities and the Partnership’s disclosure of contingent assets and liabilities at the date of the financial statements. Making accurate estimates and assumptions is particularly difficult as the oil and natural gas industry experiences challenges resulting from negative pricing pressure from the effects of COVID-19 and actions by OPEC members and other exporting nations affecting the supply and demand in global oil and natural gas markets. Many companies in the oil and natural gas industry have changed near term business plans in response to changing market conditions. The aforementioned circumstances generally increase the uncertainty in the Partnership’s accounting estimates, particularly those involving financial forecasts. The Partnership evaluates these estimates on an ongoing basis, using historical experience, consultation with experts and other methods it considers reasonable in each particular circumstance. Nevertheless, actual results may differ significantly from the Partnership’s estimates. Any effects on the Partnership’s business, financial position or results of operations resulting from revisions to these estimates are recorded in the period in which the facts that give rise to the revision become known. Significant items subject to such estimates and assumptions include, but are not limited to, (i) revenue accruals, (ii) the fair value of long-lived assets, (iii) asset retirement obligations (“ARO”) and (iv) income taxes.
Cash	Cash Cash represents unrestricted cash maintained in bank deposit accounts.
Accounts Receivable	Accounts Receivable-Related Party Accounts receivable-related party consist of receivables from Diamondback, or one of its affiliates. The receivable balance represents operating income less certain cash payments as of December 31, 2020 and 2019. Accounts Receivable-Third Party Accounts receivable consist primarily of receivables from gathering services, sourced water and rental agreements. The customers and lessees remit payment for services performed and/or goods received directly to the Partnership. Most payments for gathering services, sourced water and rental agreements are received within two months after the date of service performed or goods delivered. The Partnership adopted Accounting Standards Update (“ASU”) 2016-13 and the subsequent applicable modifications to the rule on January 1, 2020. Accounts receivable are stated at amounts due from customers and lessees, net of an allowance for expected losses as estimated by the Partnership when collection is deemed doubtful. Accounts receivable outstanding longer than the contractual payment terms are considered past due. The Partnership determines its allowance by considering a number of factors, including the length of time accounts receivable are past due, the Partnership’s previous loss history, the debtor’s current ability to pay its obligation to the Partnership, the condition of the general economy and the industry as a whole. The Partnership writes off specific accounts receivable when they become uncollectible, and payments subsequently received on such receivables are credited to the allowance for expected losses. As the adoption of ASU 2016-13 did not result in a material allowance, no cumulative-effect adjustment was made to beginning unitholders’ equity.
Sourced Water Inventory	Sourced Water Inventory Sourced water inventory is stated at the lower of historical cost or net realizable value. Inventory costs are determined under the weighted-average method.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment (“PP&E”) consist of land, gathering pipelines, facilities and related equipment, which are stated at the lower of historical cost less accumulated depreciation, amortization and accretion, or fair value, if impaired. The Partnership capitalizes construction-related direct labor and material costs. Maintenance and repair costs are expensed as incurred. PP&E assets are depreciated using the straight-line method over the useful lives of the assets ranging from ten to thirty years. Upon sale or retirement of depreciable property, the respective cost and related accumulated depreciation, amortization and accretion is eliminated from the balance sheet and the resulting gain or loss is recognized in the statement of operations.
Equity Method Investments	Equity Method Investments An investment of less than 50% in an investee over which the Partnership exercises significant influence but does not have control is accounted for using the equity method. Additionally, an investment of greater than 50% in an investee over which the Partnership does not exercise significant influence or have control is also accounted for using the equity method. Under the equity method, the Partnership’s share of the investee’s earnings or loss is recognized in the statement of operations. Judgment regarding the level of influence over each equity method investment includes considering key factors such as ownership interest, representation on the board of directors, participation in policy-making decisions, material intercompany transactions and extent of ownership by an investor in relation to the concentration of other shareholdings. Additionally, an investment in a limited liability company that maintains a specific ownership account for each investor shall be viewed as similar to an investment in a limited partnership for purposes of determining whether a noncontrolling investment shall be accounted for using the cost method or the equity method. The Partnership has determined it has the ability to exercise significant influence over its investments which constitute less than a 20% ownership interest, and does not have the ability to exercise significant influence over its investments which constitute greater than a 50% ownership interest, and therefore accounts for all of its investments under the equity method. The Partnership reviews its investments to determine if a loss in value which is other than a temporary decline has occurred. If such a loss has occurred, the Partnership recognizes an impairment provision. See Note 8—Equity Method Investments for further discussion of the Partnership’s equity method investments.
Real Estate Assets	Real Estate Assets Real estate assets are stated at cost, less accumulated depreciation and amortization. The Partnership considers the period of future benefit of each respective asset to determine the appropriate useful life and depreciation and amortization is calculated using the straight-line method over the assigned useful life. Upon acquisition of real estate properties, the purchase price is allocated to tangible assets, consisting of land and building, and to identified intangible assets and liabilities, which may include the value of above market and below market leases and the value of in-place leases. The allocation of the purchase price is based upon the fair value of each component of the property. Although independent appraisals may be used to assist in the determination of fair value, in many cases these values will be based upon management’s assessment of each property, the selling prices of comparable properties and the discounted value of cash flows from the asset. The fair values of above market and below market in-place leases will be recorded based on the present value (using an interest rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to the in-place leases and (ii) an estimate of fair market lease rates for the corresponding in-place leases measured over a period equal to the non-cancelable term of the lease including any bargain renewal periods. The above market and below market lease values will be capitalized as intangible lease assets or liabilities. Above market lease values will be amortized as an adjustment of rental income over the remaining term of the respective leases. Below market lease values will be amortized as an adjustment of rental income over the remaining term of the respective leases, including any bargain renewal periods. If a lease were to be terminated prior to its stated expiration, all unamortized amounts of above market and below market in-place lease values relating to that lease would be recorded as an adjustment to rental income. The fair values of in-place leases will include estimated direct costs associated with obtaining a new tenant, and opportunity costs associated with lost rentals which are avoided by acquiring an in-place lease. Direct costs associated with obtaining a new tenant may include commissions, tenant improvements, and other direct costs and are estimated, in part, by management’s consideration of current market costs to execute a similar lease. These direct costs will be included in intangible lease assets on the balance sheet and will be amortized to expense over the remaining term of the respective leases. The value of opportunity costs will be calculated using the contractual amounts to be paid pursuant to the in-place leases over a market absorption period for a similar lease. These intangibles will be included in intangible lease assets on the balance sheet and will be amortized to expense over the remaining term of the respective leases. If a lease were to be terminated prior to its stated expiration, all unamortized amounts of in-place lease assets relating to that lease would be expensed.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Partnership reviews its long-lived assets whenever events or circumstances indicate the carrying amount of a long-lived asset may not be recoverable. An impairment loss is recognized only if the carrying amount of a long-lived asset is not recoverable from its estimated future undiscounted cash flows. An impairment loss is the difference between the carrying amount and fair value of the asset.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Partnership’s financial instruments consist of cash, accounts receivable, other current assets, accounts payable, accrued liabilities and various other current liabilities, the revolving credit facility and Notes (as defined below). The carrying amount of cash, receivables and payables approximates fair value because of the short-term nature of the instruments. The fair value of the revolving credit facility approximates its carrying value based on the borrowing rates currently available to the Partnership for bank loans with similar terms and maturities. The fair value of the Notes are determined using quoted market prices.
Asset Retirement Obligations	Asset Retirement Obligations The Partnership recognizes a liability based on the estimated costs of retiring tangible long-lived assets. The initial liability is recognized at its fair value and measured using expected discounted future cash outflows based on internal estimates of future retirement costs when the obligation originates, which generally is when an asset is acquired or constructed. The carrying amount of the associated asset is increased commensurate with the liability recognized. Accretion expense is recognized over time as the discounted liability is accreted to its expected settlement value. Subsequent to the initial recognition, the liability is adjusted for any changes in the expected value of the retirement obligation (with a corresponding adjustment to PP&E) and for accretion of the liability due to the passage of time, until the obligation is settled. If the fair value of the estimated obligation changes, an adjustment is recorded for both the retirement liability and the associated asset carrying amount. Revisions in estimated AROs may result from changes in estimated retirement costs and the estimated timing of settling the obligations. See Note 7—Asset Retirement Obligations for further discussion of the Partnership’s asset retirement obligations.
Commitments and Contingencies	Commitments and Contingencies The Partnership may be a party to various legal proceedings, disputes and claims from time to time arising in the course of its business, including those that arise from interpretation of federal and state laws and regulations regarding air and water quality, hazardous and solid waste disposal and other environmental matters. The Partnership records reserves for contingencies related to outstanding legal proceedings, disputes or claims when information available indicates that a loss is probable and the amount of the loss can be reasonably estimated. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum amount of the range is accrued. The Partnership’s assessment is based on information known about the pending matters and its experience in contesting, litigating and settling similar matters. Actual outcomes could differ materially from the Partnership’s assessment.
Non-controlling interest	Non-controlling interest Non-controlling interest in the accompanying consolidated financial statements represents Diamondback’s ownership in the net assets of the Operating Company. When Diamondback’s relative ownership interest in the Operating Company changes, adjustments to non-controlling interest and common unitholder’s equity, tax effected, will occur. If the changes in the Partnership’s ownership interest in the Operating Company do not result in a change of control, the transactions are accounted for as equity transactions under Financial Accounting Standards Board Accounting Standards Codification (“ASC”) Topic 810, “Consolidation.” This guidance requires that any differences between the carrying value of the Partnership’s basis in the Operating Company and the fair value of the consideration received are recognized directly in equity and attributed to the controlling interest.
Revenue Recognition and Real Estate Revenue Recognition	Midstream Revenue Recognition Midstream revenues are comprised of crude oil and natural gas gathering and transportation services, produced water gathering and disposal and water sourcing and distribution services. The Partnership provides gathering and compression and water handling and treatment services under fee-based contracts based on throughput. Under these arrangements, the Partnership receives fees for gathering crude oil and natural gas, compression services, and water handling, disposal, and treatment services. The revenue the Partnership earns from these arrangements is directly related to (i) in the case of natural gas gathering and compression, the volumes of metered natural gas that the Partnership gathers, compresses, transports and delivers to other transmission delivery points, (ii) in the case of oil gathering, the volumes of metered oil that the Partnership gathers, transports and delivers to other transmission delivery points, (iii) in the case of sourced water services, the quantities of sourced water obtained, transported and delivered to the Partnership’s customers for use in their well drilling and completion operations and (iv) in the case of produced water gathering and disposal services, the quantities of produced water gathered, transported and disposed of for the Partnership’s customers. The Partnership recognizes revenue when it satisfies a performance obligation by delivering a service to a customer. The Partnership earns substantially all of its midstream revenues from commercial agreements with Diamondback and its affiliates. The following is a summary of the Partnership’s types of commercial agreements with Diamondback: •Crude Oil Gathering Agreement. Under the crude oil gathering agreements, the Partnership receives a volumetric fee per Bbl for gathering and delivering crude oil produced within the acreage subject to the acreage dedications (the “Dedicated Acreage”). •Gas Gathering and Compression Agreement. Under the gas gathering and compression agreement, the Partnership receives a volumetric fee per MMBtu for gathering and processing all natural gas produced by Diamondback within the Dedicated Acreage. •Produced and Flowback Water Gathering and Disposal Agreements. Under the produced and flowback water gathering and disposal agreements, the Partnership receives a fee for gathering or disposing of water produced from operating crude oil and natural gas wells within the Dedicated Acreage. The fee is comprised of a volumetric fee per Bbl for the produced water services the Partnership provides. In addition, the Partnership retains the skim oil that is a part of the produced water. The skim oil is processed by a third party, which provides the Partnership a volumetric fee per Bbl. •Sourced Water Purchase and Services Agreements. Under the sourced water purchase and services agreements, the Partnership receives a fee for sourcing, transporting and delivering all raw sourced water and recycled sourced water required by Diamondback and third parties to carry out its oil and natural gas activities within the Dedicated Acreage. The fee is comprised of a volumetric fee per Bbl for the type of sourced water services the Partnership provides. Performance Obligations For gathering crude oil and natural gas, delivering sourced water, and collecting, recycling and disposing of produced water, the Partnership’s performance obligations are satisfied over time using volumes delivered to measure progress. The Partnership records revenue related to the volumes delivered at the contract price at the time of delivery. For water sales, each unit sold is generally considered a distinct good and the related performance obligation is generally satisfied at a point in time (i.e., at the time control of the water is transferred to the customer). The Partnership recognizes revenue from the sale of water when its contracted performance obligation to deliver water is satisfied and control of the water is transferred to the customer. This usually occurs when the water is delivered to the location specified in the contract and the title and risks of rewards and ownership are transferred to the customer. Transaction Price Allocated to Remaining Performance Obligations Under its revenue agreements, each delivery generally represents a separate performance obligation; therefore, future volumes delivered are wholly unsatisfied and disclosure of the transaction price allocated to remaining performance obligations is not required. Contract Balances Under the Partnership’s revenue agreements, the Partnership invoices customers after the Partnership’s performance obligations have been satisfied, at which point payment is unconditional. As such, the Partnership’s revenue agreements do not give rise to contract assets or liabilities. Real Estate Revenue Recognition The Partnership recognizes rental revenue from tenants on a straight-line basis over the lease term when collectability is reasonably assured and the tenant has taken possession or controls the physical use of the leased asset. Rental income—related party is comprised of revenues earned from lease agreements with Diamondback and its affiliates. Other real estate revenue is derived from tenants’ use of parking, telecommunications and miscellaneous services. Parking and other miscellaneous service revenue is recognized when the related services are utilized by the tenants. Tenant recoveries related to reimbursement of real estate taxes, insurance, repairs and maintenance and other operating expenses are recognized as revenue in the period the applicable expenses are incurred. The reimbursements are recognized and presented gross, as the Partnership is generally the primary obligor with respect to purchasing goods and services from third-party suppliers, has discretion in selecting the supplier and bears the associated credit risk.
Concentrations	Concentrations The Partnership derives substantially all of its revenue from our commercial agreements with Diamondback, which carry initial terms ending in 2034. The Partnership operates produced water disposal wells with other working interest owners. The revenues and expenses related to these disposal activities are reported on a net basis as part of revenues and costs and expenses.
Income Taxes	Income Taxes The Partnership is treated as a corporation for U.S. federal income tax purposes as a result of its election to be treated as a corporation effective May 24, 2019. Subsequent to the effective date of the Partnership’s election, it is subject to U.S. federal and state income tax at corporate rates. The Partnership uses the asset and liability method of accounting for income taxes, under which deferred tax assets and liabilities are recognized for the future tax consequences of (i) temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities and (ii) operating loss and tax credit carryforwards. Deferred income tax assets and liabilities are based on enacted tax rates applicable to the future period when those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period the rate change is enacted. A valuation allowance is provided for deferred tax assets when it is more likely than not the deferred tax assets will not be realized. The Partnership is continuing its practice of recognizing interest and penalties related to income tax matters as interest expense and general and administrative expenses, respectively. During the year ended December 31, 2020, there was no interest or penalties associated with uncertain tax positions recognized in the Partnership’s consolidated financial statements. See Note 14—Income Taxes for further details.
Capital Contributions	Capital Contributions A contribution of a set of assets and related liabilities (a “set”) to the Partnership from Diamondback is analyzed to determine whether the set meets the definition of a business in Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 805, “Business Combinations”. A contribution of a set of assets that does not constitute a business is recognized at the date of the transfer at its carrying amount in the accounts of Diamondback in accordance with the guidance regarding transactions between entities under common control in ASC 805-50. Management then evaluates whether the asset contribution results in a change in the reporting entity, as defined in ASC Topic 250, “Accounting Changes and Error Corrections”. An asset contribution that does not constitute a change in the reporting entity is accounted for prospectively from the date of the transfer, while an asset contribution that constitutes a change in the reporting entity would result in retrospective application of the transaction.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Adopted Pronouncements In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses”. This update affects entities holding financial assets and net investment in leases that are not accounted for at fair value through net income. The amendments affect loans, debt securities, trade receivables, net investments in leases, off-balance sheet credit exposures, reinsurance receivables, and any other financial assets not excluded from the scope that have the contractual right to receive cash. The Partnership adopted this update effective January 1, 2020. The adoption of this update did not have a material impact on the Partnership’s financial position, results of operations or liquidity since it does not have a history of credit losses. Accounting Pronouncements Not Yet Adopted In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes". This update is intended to simplify the accounting for income taxes by removing certain exceptions and by clarifying and amending existing guidance. This update is effective for public business entities beginning after December 15, 2020 with early adoption permitted. The Partnership does not believe that the adoption of this update will have an impact on its financial position, results of operations or liquidity. The Partnership considers the applicability and impact of all ASUs. ASUs not listed above were assessed and determined to be either not applicable or clarifications of ASUs previously disclosed.
Revenue from Contracts with Customers	The Partnership generates revenues by charging fees on a per unit basis for gathering crude oil and natural gas, delivering and storing sourced water, and collecting, recycling and disposing of produced water.
Fair Value Measurements	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The fair value hierarchy is based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value. The Partnership’s assessment of the significance of a particular input to the fair value measurements requires judgment and may affect the valuation of the assets and liabilities being measured and their placement within the fair value hierarchy. The Partnership uses appropriate valuation techniques based on available inputs to measure the fair values of its assets and liabilities. Level 1 - Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets as of the reporting date. Level 2 - Observable market-based inputs or unobservable inputs that are corroborated by market data. These are inputs other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date. Level 3 - Unobservable inputs that are not corroborated by market data and may be used with internally developed methodologies that result in management’s best estimate of fair value. Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2020

Prior to May 28, 2019, the Partnership’s services were performed by the Predecessor. The consolidated financial statements include the results of the Predecessor for the periods presented prior to the closing of the IPO on May 28, 2019. The Predecessor financial statements have been prepared from the separate records maintained by the Partnership and may not necessarily be indicative of the actual results of operations that might have occurred if the Predecessor had been operated separately during the periods reported.

The consolidated results of operations following the completion of the IPO are presented together with the results of operations pertaining to the Predecessor. The assets of the Predecessor consist of produced water disposal wells and related

gathering systems, office buildings, surface land and an oil gathering system and asset retirement obligations related to these assets, which were contributed effective January 1, 2019. See Note 4—Acquisitions. The capital contribution of the net proceeds from the IPO to the Operating Company in exchange for 29% of the limited liability company units of the Operating Company was accounted for as a combination of entities under common control, with assets and liabilities transferred at their carrying amounts in a manner similar to a pooling of interests. The Partnership did not own any assets prior to May 28, 2019, the date of the equity contribution agreement by and between the Partnership and the Predecessor. Prior to the IPO, the Predecessor was a wholly owned subsidiary of Diamondback.

For periods prior to May 28, 2019, the accompanying consolidated financial statements and related notes thereto represent the financial position, results of operations, cash flows and changes in members’ equity of the Predecessor and, for periods on and after May 28, 2019, the accompanying consolidated financial statements and related notes thereto represent the financial position, results of operations, cash flows and changes in unitholders’ equity of the Partnership and its partially owned subsidiary, the Operating Company.

The Partnership’s operations are reported in two operating business segments: (i) midstream services and (ii) real estate operations.

The consolidated financial statements include the accounts of the Partnership and its subsidiaries after all significant intercompany balances and transactions have been eliminated upon consolidation.

Reclassifications

Certain prior period amounts have been reclassified to conform to the current period financial statement presentation. These reclassifications had no effect on the previously reported total assets, total liabilities, unitholders’ equity, results of operations or cash flows.

Use of Estimates

Certain amounts included in or affecting the Partnership’s financial statements and related notes must be estimated by management, requiring certain assumptions to be made with respect to values or conditions that cannot be known with certainty at the time the financial statements are prepared. These estimates and assumptions affect the amounts the Partnership reports for assets and liabilities and the Partnership’s disclosure of contingent assets and liabilities at the date of the financial statements.

Making accurate estimates and assumptions is particularly difficult as the oil and natural gas industry experiences challenges resulting from negative pricing pressure from the effects of COVID-19 and actions by OPEC members and other exporting nations affecting the supply and demand in global oil and natural gas markets. Many companies in the oil and natural gas industry have changed near term business plans in response to changing market conditions. The aforementioned circumstances generally increase the uncertainty in the Partnership’s accounting estimates, particularly those involving financial

forecasts.

The Partnership evaluates these estimates on an ongoing basis, using historical experience, consultation with experts and other methods it considers reasonable in each particular circumstance. Nevertheless, actual results may differ significantly from the Partnership’s estimates. Any effects on the Partnership’s business, financial position or results of operations resulting from revisions to these estimates are recorded in the period in which the facts that give rise to the revision become known. Significant items subject to such estimates and assumptions include, but are not limited to, (i) revenue accruals, (ii) the fair value of long-lived assets, (iii) asset retirement obligations (“ARO”) and (iv) income taxes.

Cash

Cash Cash represents unrestricted cash maintained in bank deposit accounts.

Accounts Receivable

Accounts Receivable-Related Party

Accounts receivable-related party consist of receivables from Diamondback, or one of its affiliates. The receivable balance represents operating income less certain cash payments as of December 31, 2020 and 2019.

Accounts Receivable-Third Party

Accounts receivable consist primarily of receivables from gathering services, sourced water and rental agreements. The customers and lessees remit payment for services performed and/or goods received directly to the Partnership. Most payments for gathering services, sourced water and rental agreements are received within two months after the date of service performed or goods delivered.

The Partnership adopted Accounting Standards Update (“ASU”) 2016-13 and the subsequent applicable modifications to the rule on January 1, 2020. Accounts receivable are stated at amounts due from customers and lessees, net of an allowance for expected losses as estimated by the Partnership when collection is deemed doubtful. Accounts receivable outstanding longer than the contractual payment terms are considered past due. The Partnership determines its allowance by considering a number of factors, including the length of time accounts receivable are past due, the Partnership’s previous loss history, the debtor’s current ability to pay its obligation to the Partnership, the condition of the general economy and the industry as a whole. The Partnership writes off specific accounts receivable when they become uncollectible, and payments subsequently received on such receivables are credited to the allowance for expected losses. As the adoption of ASU 2016-13 did not result in a material allowance, no cumulative-effect adjustment was made to beginning unitholders’ equity.

Sourced Water Inventory

Sourced water inventory is stated at the lower of historical cost or net realizable value. Inventory costs are determined under the weighted-average method.

Property, Plant and Equipment

Property, Plant and Equipment Property, plant and equipment (“PP&E”) consist of land, gathering pipelines, facilities and related equipment, which are stated at the lower of historical cost less accumulated depreciation, amortization and accretion, or fair value, if impaired. The Partnership capitalizes construction-related direct labor and material costs. Maintenance and repair costs are expensed as incurred. PP&E assets are depreciated using the straight-line method over the useful lives of the assets ranging from ten to thirty years. Upon sale or retirement of depreciable property, the respective cost and related accumulated depreciation, amortization and accretion is eliminated from the balance sheet and the resulting gain or loss is recognized in the statement of operations.

Equity Method Investments

An investment of less than 50% in an investee over which the Partnership exercises significant influence but does not have control is accounted for using the equity method. Additionally, an investment of greater than 50% in an investee over which the Partnership does not exercise significant influence or have control is also accounted for using the equity method. Under the equity method, the Partnership’s share of the investee’s earnings or loss is recognized in the statement of operations.

Judgment regarding the level of influence over each equity method investment includes considering key factors such as ownership interest, representation on the board of directors, participation in policy-making decisions, material intercompany transactions and extent of ownership by an investor in relation to the concentration of other shareholdings. Additionally, an investment in a limited liability company that maintains a specific ownership account for each investor shall be viewed as similar to an investment in a limited partnership for purposes of determining whether a noncontrolling investment shall be accounted for using the cost method or the equity method. The Partnership has determined it has the ability to exercise significant influence over its investments which constitute less than a 20% ownership interest, and does not have the ability to exercise significant influence over its investments which constitute greater than a 50% ownership interest, and therefore accounts for all of its investments under the equity method.

The Partnership reviews its investments to determine if a loss in value which is other than a temporary decline has occurred. If such a loss has occurred, the Partnership recognizes an impairment provision. See Note 8—Equity Method Investments for further discussion of the Partnership’s equity method investments.

Real Estate Assets

Real estate assets are stated at cost, less accumulated depreciation and amortization. The Partnership considers the period of future benefit of each respective asset to determine the appropriate useful life and depreciation and amortization is calculated using the straight-line method over the assigned useful life.

Upon acquisition of real estate properties, the purchase price is allocated to tangible assets, consisting of land and building, and to identified intangible assets and liabilities, which may include the value of above market and below market leases and the value of in-place leases. The allocation of the purchase price is based upon the fair value of each component of the property. Although independent appraisals may be used to assist in the determination of fair value, in many cases these values will be based upon management’s assessment of each property, the selling prices of comparable properties and the discounted value of cash flows from the asset.

The fair values of above market and below market in-place leases will be recorded based on the present value (using an interest rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to the in-place leases and (ii) an estimate of fair market lease rates for the corresponding in-place leases measured over a period equal to the non-cancelable term of the lease including any bargain renewal periods. The above market and below market lease values will be capitalized as intangible lease assets or liabilities. Above market lease values will be amortized as an adjustment of rental income over the remaining term of the respective leases. Below market lease values will be amortized as an adjustment of rental income over the remaining term of the respective leases, including any bargain renewal periods. If a lease were to be terminated prior to its stated expiration, all unamortized amounts of above market and below market in-place lease values relating to that lease would be recorded as an adjustment to rental income.

The fair values of in-place leases will include estimated direct costs associated with obtaining a new tenant, and opportunity costs associated with lost rentals which are avoided by acquiring an in-place lease. Direct costs associated with obtaining a new tenant may include commissions, tenant improvements, and other direct costs and are estimated, in part, by management’s consideration of current market costs to execute a similar lease. These direct costs will be included in intangible lease assets on the balance sheet and will be amortized to expense over the remaining term of the respective leases. The value of opportunity costs will be calculated using the contractual amounts to be paid pursuant to the in-place leases over a market absorption period for a similar lease. These intangibles will be included in intangible lease assets on the balance sheet and will be amortized to expense over the remaining term of the respective leases. If a lease were to be terminated prior to its stated expiration, all unamortized amounts of in-place lease assets relating to that lease would be expensed.

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets The Partnership reviews its long-lived assets whenever events or circumstances indicate the carrying amount of a long-lived asset may not be recoverable. An impairment loss is recognized only if the carrying amount of a long-lived asset is not recoverable from its estimated future undiscounted cash flows. An impairment loss is the difference between the carrying amount and fair value of the asset.

Fair Value of Financial Instruments

Fair Value of Financial Instruments The Partnership’s financial instruments consist of cash, accounts receivable, other current assets, accounts payable, accrued liabilities and various other current liabilities, the revolving credit facility and Notes (as defined below). The carrying amount of cash, receivables and payables approximates fair value because of the short-term nature of the instruments. The fair value of the revolving credit facility approximates its carrying value based on the borrowing rates currently available to the Partnership for bank loans with similar terms and maturities. The fair value of the Notes are determined using quoted market prices.

Asset Retirement Obligations

Asset Retirement Obligations The Partnership recognizes a liability based on the estimated costs of retiring tangible long-lived assets. The initial liability is recognized at its fair value and measured using expected discounted future cash outflows based on internal estimates of future retirement costs when the obligation originates, which generally is when an asset is acquired or constructed. The carrying amount of the associated asset is increased commensurate with the liability recognized. Accretion expense is recognized over time as the discounted liability is accreted to its expected settlement value. Subsequent to the initial recognition, the liability is adjusted for any changes in the expected value of the retirement obligation (with a corresponding adjustment to PP&E) and for accretion of the liability due to the passage of time, until the obligation is settled. If the fair value of the estimated obligation changes, an adjustment is recorded for both the retirement liability and the associated asset carrying amount. Revisions in estimated AROs may result from changes in estimated retirement costs and the estimated timing of settling the obligations. See Note 7—Asset Retirement Obligations for further discussion of the Partnership’s asset retirement obligations.

Commitments and Contingencies

Commitments and Contingencies The Partnership may be a party to various legal proceedings, disputes and claims from time to time arising in the course of its business, including those that arise from interpretation of federal and state laws and regulations regarding air and water quality, hazardous and solid waste disposal and other environmental matters. The Partnership records reserves for contingencies related to outstanding legal proceedings, disputes or claims when information available indicates that a loss is probable and the amount of the loss can be reasonably estimated. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum amount of the range is accrued. The Partnership’s assessment is based on information known about the pending matters and its experience in contesting, litigating and settling similar matters. Actual outcomes could differ materially from the Partnership’s assessment.

Non-controlling interest

Non-controlling interest in the accompanying consolidated financial statements represents Diamondback’s ownership in the net assets of the Operating Company. When Diamondback’s relative ownership interest in the Operating Company changes, adjustments to non-controlling interest and common unitholder’s equity, tax effected, will occur. If the changes in the Partnership’s ownership interest in the Operating Company do not result in a change of control, the transactions are accounted for as equity transactions under Financial Accounting Standards Board Accounting Standards Codification (“ASC”) Topic 810,

“Consolidation.” This guidance requires that any differences between the carrying value of the Partnership’s basis in the Operating Company and the fair value of the consideration received are recognized directly in equity and attributed to the controlling interest.

Revenue Recognition and Real Estate Revenue Recognition

Midstream Revenue Recognition

Midstream revenues are comprised of crude oil and natural gas gathering and transportation services, produced water gathering and disposal and water sourcing and distribution services. The Partnership provides gathering and compression and water handling and treatment services under fee-based contracts based on throughput. Under these arrangements, the Partnership receives fees for gathering crude oil and natural gas, compression services, and water handling, disposal, and treatment services. The revenue the Partnership earns from these arrangements is directly related to (i) in the case of natural gas gathering and compression, the volumes of metered natural gas that the Partnership gathers, compresses, transports and delivers to other transmission delivery points, (ii) in the case of oil gathering, the volumes of metered oil that the Partnership gathers, transports and delivers to other transmission delivery points, (iii) in the case of sourced water services, the quantities of sourced water obtained, transported and delivered to the Partnership’s customers for use in their well drilling and completion operations and (iv) in the case of produced water gathering and disposal services, the quantities of produced water gathered, transported and disposed of for the Partnership’s customers. The Partnership recognizes revenue when it satisfies a performance obligation by delivering a service to a customer. The Partnership earns substantially all of its midstream revenues from commercial agreements with Diamondback and its affiliates.

The following is a summary of the Partnership’s types of commercial agreements with Diamondback:

•Crude Oil Gathering Agreement. Under the crude oil gathering agreements, the Partnership receives a volumetric fee per Bbl for gathering and delivering crude oil produced within the acreage subject to the acreage dedications (the “Dedicated Acreage”).

•Gas Gathering and Compression Agreement. Under the gas gathering and compression agreement, the Partnership receives a volumetric fee per MMBtu for gathering and processing all natural gas produced by Diamondback within the Dedicated Acreage.

•Produced and Flowback Water Gathering and Disposal Agreements. Under the produced and flowback water gathering and disposal agreements, the Partnership receives a fee for gathering or disposing of water produced from operating crude oil and natural gas wells within the Dedicated Acreage. The fee is comprised of a volumetric fee per Bbl for the produced water services the Partnership provides. In addition, the Partnership retains the skim oil that is a part of the produced water. The skim oil is processed by a third party, which provides the Partnership a volumetric fee per Bbl.

•Sourced Water Purchase and Services Agreements. Under the sourced water purchase and services agreements, the Partnership receives a fee for sourcing, transporting and delivering all raw sourced water and recycled sourced water required by Diamondback and third parties to carry out its oil and natural gas activities within the Dedicated Acreage. The fee is comprised of a volumetric fee per Bbl for the type of sourced water services the Partnership provides.

Performance Obligations

For gathering crude oil and natural gas, delivering sourced water, and collecting, recycling and disposing of produced water, the Partnership’s performance obligations are satisfied over time using volumes delivered to measure progress. The Partnership records revenue related to the volumes delivered at the contract price at the time of delivery.

For water sales, each unit sold is generally considered a distinct good and the related performance obligation is generally satisfied at a point in time (i.e., at the time control of the water is transferred to the customer). The Partnership recognizes revenue from the sale of water when its contracted performance obligation to deliver water is satisfied and control of the water is transferred to the customer. This usually occurs when the water is delivered to the location specified in the contract and the title and risks of rewards and ownership are transferred to the customer.

Transaction Price Allocated to Remaining Performance Obligations

Under its revenue agreements, each delivery generally represents a separate performance obligation; therefore, future volumes delivered are wholly unsatisfied and disclosure of the transaction price allocated to remaining performance obligations is not required.

Contract Balances

Under the Partnership’s revenue agreements, the Partnership invoices customers after the Partnership’s performance obligations have been satisfied, at which point payment is unconditional. As such, the Partnership’s revenue agreements do not give rise to contract assets or liabilities.

Real Estate Revenue Recognition

The Partnership recognizes rental revenue from tenants on a straight-line basis over the lease term when collectability is reasonably assured and the tenant has taken possession or controls the physical use of the leased asset. Rental income—related party is comprised of revenues earned from lease agreements with Diamondback and its affiliates. Other real estate revenue is derived from tenants’ use of parking, telecommunications and miscellaneous services. Parking and other miscellaneous service revenue is recognized when the related services are utilized by the tenants. Tenant recoveries related to reimbursement of real estate taxes, insurance, repairs and maintenance and other operating expenses are recognized as revenue in the period the applicable expenses are incurred. The reimbursements are recognized and presented gross, as the Partnership is generally the primary obligor with respect to purchasing goods and services from third-party suppliers, has discretion in selecting the supplier and bears the associated credit risk.

Concentrations

Concentrations The Partnership derives substantially all of its revenue from our commercial agreements with Diamondback, which carry initial terms ending in 2034. The Partnership operates produced water disposal wells with other working interest owners. The revenues and expenses related to these disposal activities are reported on a net basis as part of revenues and costs and expenses.

Income Taxes

The Partnership is treated as a corporation for U.S. federal income tax purposes as a result of its election to be treated as a corporation effective May 24, 2019. Subsequent to the effective date of the Partnership’s election, it is subject to U.S. federal and state income tax at corporate rates. The Partnership uses the asset and liability method of accounting for income taxes, under which deferred tax assets and liabilities are recognized for the future tax consequences of (i) temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities and (ii) operating loss and tax credit carryforwards. Deferred income tax assets and liabilities are based on enacted tax rates applicable to the future period when those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period the rate change is enacted. A valuation allowance is provided for deferred tax assets when it is more likely than not the deferred tax assets will not be realized.

The Partnership is continuing its practice of recognizing interest and penalties related to income tax matters as interest expense and general and administrative expenses, respectively. During the year ended December 31, 2020, there was no interest or penalties associated with uncertain tax positions recognized in the Partnership’s consolidated financial statements. See Note 14—Income Taxes for further details.

Capital Contributions

A contribution of a set of assets and related liabilities (a “set”) to the Partnership from Diamondback is analyzed to determine whether the set meets the definition of a business in Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 805, “Business Combinations”. A contribution of a set of assets that does not constitute a business is recognized at the date of the transfer at its carrying amount in the accounts of Diamondback in accordance with the guidance regarding transactions between entities under common control in ASC 805-50. Management then evaluates whether the asset contribution results in a change in the reporting entity, as defined in ASC Topic 250, “Accounting Changes and Error Corrections”. An asset contribution that does not constitute a change in the reporting entity is accounted for prospectively from

the date of the transfer, while an asset contribution that constitutes a change in the reporting entity would result in retrospective application of the transaction.

Recent Accounting Pronouncements

Recently Adopted Pronouncements

In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses”. This update affects entities holding financial assets and net investment in leases that are not accounted for at fair value through net income. The amendments affect loans, debt securities, trade receivables, net investments in leases, off-balance sheet credit exposures, reinsurance receivables, and any other financial assets not excluded from the scope that have the contractual right to receive cash. The Partnership adopted this update effective January 1, 2020. The adoption of this update did not have a material impact on the Partnership’s financial position, results of operations or liquidity since it does not have a history of credit losses.

Accounting Pronouncements Not Yet Adopted

In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes". This update is intended to simplify the accounting for income taxes by removing certain exceptions and by clarifying and amending existing guidance. This update is effective for public business entities beginning after December 15, 2020 with early adoption permitted. The Partnership does not believe that the adoption of this update will have an impact on its financial position, results of operations or liquidity.

The Partnership considers the applicability and impact of all ASUs. ASUs not listed above were assessed and determined to be either not applicable or clarifications of ASUs previously disclosed.

Revenue from Contracts with Customers

The Partnership generates revenues by charging fees on a per unit basis for gathering crude oil and natural gas, delivering and storing sourced water, and collecting, recycling and disposing of produced water.

Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs.

The fair value hierarchy is based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value. The Partnership’s assessment of the significance of a particular input to the fair value measurements requires judgment and may affect the valuation of the assets and liabilities being measured and their placement within the fair value hierarchy. The Partnership uses appropriate valuation techniques based on available inputs to measure the fair values of its assets and liabilities.

Level 1 - Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets as of the reporting date.

Level 2 - Observable market-based inputs or unobservable inputs that are corroborated by market data. These are inputs other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date.

Level 3 - Unobservable inputs that are not corroborated by market data and may be used with internally developed methodologies that result in management’s best estimate of fair value.

Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement.