Tex. Water Code § 13.147

(a) A retail public utility providing water service may contract with a retail public utility providing sewer service to bill and collect the sewer service provider's fees and payments as part of a consolidated process with the billing and collection of the water service provider's fees and payments. The water service provider may provide that service only for customers who are served by both providers in an area covered by both providers' certificates of public convenience and necessity. If the water service provider refuses to enter into a contract under this section or if the water service provider and sewer service provider cannot agree on the terms of a contract, the sewer service provider may petition the utility commission to issue an order requiring the water service provider to provide that service.

(b) A contract or order under this section must provide procedures and deadlines for submitting billing and customer information to the water service provider and for the delivery of collected fees and payments to the sewer service provider.

(c) A contract or order under this section may require or permit a water service provider that provides consolidated billing and collection of fees and payments to:

(1) terminate the water services of a person whose sewage services account is in arrears for nonpayment; and

(2) charge a customer a reconnection fee if the customer's water service is terminated for nonpayment of the customer's sewage services account.

(d) A water service provider that provides consolidated billing and collection of fees and payments may impose on each sewer service provider customer a reasonable fee to recover costs associated with providing consolidated billing and collection of fees and payments for sewage services.