The Angelina and Neches River Authority was originally established in 1949 as the Neches River Conservation District. Before that time it had been part of the Sabine-Neches River Conservation District, established by the Texas legislature in 1935. The Neches River Conservation District was inactive until 1971, when Governor Preston Smith appointed nine members to the board of directors. In 1977 the district's name was changed to Angelina and Neches River Authority. It held jurisdiction over parts of sixteen East Texas counties and included the upper Neches River basin.
Throughout the 1970s the agency implemented various plans and projects to promote water-resource development, water-quality management, and water conservation. It managed water-quality studies of the upper Neches basin, assisted wastewater treatment plants, and conducted field analysis, sample collection, and industrial-waste analysis for the cities of Jacksonville and Lufkin. Additionally, the organization also provided analyses for the forest service and petroleum service industries, cities, water-supply corporations, and private citizens to test for drinking water contamination. The Texas legislature authorized the Angelina and Neches River Authority Industrial Development Corporation in the late 1970s. It is a nonprofit corporation established to furnish certain kinds of bond financing for private industry.
In the 1980s the Texas Department of Water Resources contracted the ANRA to conduct studies on various aspects of sewage treatment. These included the evaluation of the operation and maintenance of seven municipal sewage-treatment plants in East Texas in 1982 and a study of sludge-disposal methods for all municipal sewage-treatment plants in the upper Neches basin in 1985. Also in 1985 the Texas Water Commission approved the construction of Lake Eastex, a proposed reservoir in Cherokee County.
In 1990 the authority conducted the Nacogdoches County Water Study to determine the need for an increased water supply over the next fifty years. It concluded that water consumption should move toward greater use of surface water such as Lake Nacogdoches for the city of Nacogdoches and Lake Naconiche, a proposed United States Soil Service lake, for a number of county water-supply entities. During the early 1990s the Angelina and Neches River Authority continued to proceed with the necessary permits and acquisitions for Lake Eastex. It conducted analyses for treatment plants, monitored wastewater discharge into the Angelina River, and examined water quality of twelve stream locations for the United States Forest Service. It regulated a septic-tank licensing program around the Sam Rayburn Reservoir. The agency operated nine wastewater plants and one water-treatment plant and performed wastewater analyses and coliform testing of drinking water for cities, school districts, water corporations, industrial groups, and other clients. In 1992 it submitted its first report on the water quality of the upper Neches basin in accord with the rules of the 1991 Clean Rivers Act. The Angelina and Neches River Authority does not have any taxing authority. It receives income through customer payments for agency services. Agency headquarters are located in Lufkin.