In 1947, the Lugert-Altus dam was replaced with a concrete gravity dam that substantially increased the storage capacity of the Lake. At this time, the first canal from the lake was completed. Over the next several years, more canals were be built. By 1953 the irrigation system had more than 200 miles of canals and was managed by the Lugert-Altus Irrigation District.

The main canal runs within 50 feet of the Altus Reservoir so a connecting pipe with gate valves was installed to allow Lugert-Altus water to flow into the city reservoir. This served as a means of replenishing water during times of drought. The City paid $1,080,000 towards the irrigation system construction.

In 1964, the City of Altus began construction of well fields in the Seymour Aquifer just over the border in North Wilbarger County, Texas. 18 wells were installed which became the primary water source for the public water supply. This project cost about $2,000,000. The wells were on private property (most at the Round Timber Ranch) and long-term lease agreements were executed.

In 1975 the Tom Steed Reservoir was built by the U.S. Bureau of Land Reclamation in Kiowa County. Additionally, a 36-inch pipeline 23 miles long was constructed to bring Tom Steed water to the Altus Water Treatment Plant. Use of the well fields continued and well water was blended with Treated water from Tom Steed for the Altus water supply. Also in 1975, construction was completed for a new Water Treatment Plant which was a mixed media filtration plant with primary clarifiers and chlorine disinfection.

After about 30 years of operation, the wells were shut down due to increasing maintenance costs.

In 2005, the City constructed a Reverse Osmosis Treatment facility with membrane filtration as pre-treatment. The R.O. plant was in operation for several years but there were problems with the membrane filtration portion. The R.O. Plant was shut down in 2012.