Rio Grande Watermaster Program

About the Rio Grande Watermaster Program

This Watermaster program was established after a lawsuit between the State of Texas vs. HCWC&ID No. 18 and others was finalized in 1971, resulting in the final adjudication of the Lower Rio Grande water rights.

In the Rio Grande basin above Lake Amistad (the Upper Rio Grande), water rights are managed using a “first in time, first in right” priority system, as they are in other parts of Texas. Water rights in the Middle and Lower Rio Grande are served by the Falcon-Amistad reservoir system. Water below Lake Amistad is allocated on an account basis, much like having a bank account with a constantly changing balance. Priority is given to all municipal accounts, which means that at the beginning of each year the storage balance for each municipal account resets to its full authorized water-right amount. The municipal priority is guaranteed by the monthly reestablishment of a municipal reserve in the system of 225,000 acre-feet, which is equivalent to one year of average diversions for all municipal demands below Amistad for Texas users.

Irrigation accounts, on the other hand, must rely on balances that are carried forward, as irrigation accounts are not reset at the beginning of the year. Each month the watermaster determines how much unallocated water assigned to the United States is contained in the Falcon-Amistad system. If surplus water is identified in a given month, it is allocated to the irrigation accounts. When water is used, it is subtracted from the respective account by type of use from the account’s usable balance. This system of accounting for water usage was put in place after an international treaty with Mexico was established, and in accordance with a 1969 District Court ruling.

Jurisdiction

Duties of the Watermaster

Duties include:

• coordinating releases and diversions
• monitoring stream flow, reservoir levels, and water use within the basin
• enforcing compliance with water rights
• responding to complaints

Rio Grande Watermaster Advisory Committee

Advisory Committee

The Rio Grande Watermaster Advisory Committee was established in January 1998 in accordance with the Texas Water Code Section (§)11.3261.

Rio Grande Watermaster Program Area: Water and Water Right Sales

Water Right holders in the Rio Grande Watermaster Program area interested in selling water under a Rio Grande watermaster contract* or selling a water right in full or in part, can provide information for posting on this website by completing the form(s) below.

Sales Forms

• Provide information on contractual sales.  Rio Grande Watermaster Contractual Sales

• Provide information on a water right for sale.  Rio Grande Water Right Sales

Sales information will be posted until further notice. Forms submitted on or before the 25^th of the current month and will be posted on or before the 7^th the following month.    

Current List of Water for Sale

• Rio Grande Watermaster Contractual Sales
• Rio Grande Water Rights for Sale

*This information requested is applicable to Lower and Middle Rio Grande River segments only. 

Rio Grande Water Right Sales Pursuant to TWC §49.504(b)(2)(A)

Texas Water Code §49.504(b)(2)(A) requires some municipal water suppliers (Districts) to advertise the offer to sell or contract its water by posting notice on the Rio Grande Watermaster’s website for 90 days.

• Please send an email to riowm@tceq.texas.gov to Provide information on a water right sale pursuant to §49.504(b)(2)(A)

Rio Grande Regional Water Authority

Acts of the 80th Legislature, Regular Session, 2007, Section 3.08 requires the Rio Grande Watermaster to provide the Rio Grande Regional Water Authority with a list of all water rights and the authorized use for each right within its boundaries. 

• Rio Grande Water Right Accounts

Rio Grande Watermaster Contact Information