The Partnership generates revenues by charging fees on a per unit basis for gathering crude oil and natural gas, delivering and storing fresh water, and collecting, recycling and disposing of produced water. The Partnership adopted ASC Topic 606, Revenue from Contracts with Customers (ASC Topic 606) on January 1, 2018, using the modified retrospective method. Under ASC Topic 606, performance obligations are the unit of account and generally represent distinct goods or services that are promised to customers. The adoption of ASC Topic 606 did not have a material impact on the recognition, measurement and presentation of the Partnerships revenues and expenses. Performance Obligations : For gathering crude oil and natural gas, delivering fresh water, and collecting, recycling and disposing of produced water, the Partnerships 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. The Partnership began generating revenue from water sales during first quarter 2018 upon the contribution of fresh water assets from Diamondback. For its 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 : The majority of the Partnerships revenue agreements have a term greater than one year and, as such, the Partnership has utilized the practical expedient in ASC Topic 606, which states that the Partnership is not required to disclose the transaction price allocated to remaining performance obligations if the variable consideration is allocated entirely to a wholly unsatisfied performance obligation. 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. The remainder of the Partnerships revenue agreements, which relate to agreements with third parties, are short-term in nature with a term of one year or less. The Partnership has utilized an additional practical expedient in ASC Topic 606 which exempts it from disclosure of the transaction price allocated to remaining performance obligations if the performance obligation is part of an agreement that has an original expected duration of one year or less. Contract Balances : Under the Partnerships revenue agreements, the Partnership invoices customers after our performance obligations have been satisfied, at which point payment is unconditional. As such, the Partnerships revenue agreements do not give rise to contract assets or liabilities under ASC Topic 606. The following is a summary of the Partnerships types of revenue agreements:  Crude Oil Gathering Agreement . Under the crude oil gathering agreement, the Partnership receives a volumetric fee per barrel (Bbl) for gathering and delivering crude oil produced by Diamondback within the dedicated acreage.  Gas Gathering and Compression Agreement . Under the gas gathering and compression agreement, the Partnership receives a volumetric fee per million British Thermal Unit (MMBtu) for gathering and processing all natural gas produced by Diamondback within the dedicated acreage.  Produced and Flowback Water Gathering and Disposal Agreement . Under the produced and flowback water gathering and disposal agreement, 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.  Fresh water Purchase and Services Agreement . Under the fresh water purchase and services agreement, the Partnership receives a fee for sourcing, transporting and delivering all raw fresh water and recycled fresh water required by Diamondback 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 fresh water services the Partnership provides. Real Estate Contracts: 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 incomerelated 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. It is noted that surface revenue, rental and real estate income and amortization of out of market leases is outside the scope of ASC Topic 606.