Concerns that Lake Brownwood might not be able to provide all the water Brown County needs if drought persists have prompted the Brown County Water Improvement District No. 1 to begin exploring groundwater as supply options.
But it was a looming crisis of the opposite kind — flood conditions at the lake — that led the district to make major infrastructure improvements in the late 1970s and early 1980s.
An investigation of the Lake Brownwood Dam by the U.S. Army Corps of Engineers resulted in the condemnation of the dam in April 1978, water district records show. The "Red Jacket Report" said that the dam would not retard the "probable maximum flood" — the flood caused by a 500-year frequency rainfall.
After heavy rains in November 1977, the earthen Kelly Barnes Dam in northeast Georgia collapsed, resulting in almost three dozen deaths and subsequent federal inspections of dams throughout the nation. Studies determined that even though the Lake Brownwood Dam was structurally sound, a flood of historic proportions would likely push water over it — an event which could compromise the structure’s stability.
A seemingly remote possibility became a very real concern in 1978 after the remnants of a tropical storm were met by a cool front over North Texas, dumping more than a foot of water in the Graham and Albany area.
Tropical Storm Amelia had crossed the Texas coast as a weak and unorganized system in late July 1978, but it brought massive amounts of moisture inland. Flooding caused 33 fatalities and an estimated $110 million in damages in what Gov. Dolph Briscoe called one of the worst floods in the state's history. President Jimmy Carter issued a federal disaster proclamation for six counties.
Hydrologists calculated that if the strongest part of the storm had been 70 miles south, floodwater would have topped the Brownwood dam. Specifically, the study determined that the dam at its current height would retard only 60 percent of the probable maximum flood.
A $4,975,000 project to raise the lake dam level by 20 feet and make outlet modifications was begun. The study of the project was completed in November 1979 at a cost of $230,000, and construction that increased the dam’s mass by one-third was completed in August 1983.
The need for this and other improvements arose quickly in the late 1970s. According to the water district’s website, they included projects costing a total of more than $17 million that resulted in the construction of a permanent auxiliary pipeline and pump station; construction of dam improvements and outlet works that reinforced the dam; construction of a main gravity pipeline and pump station; and treatment plant renovations and expansion.
Another project installed an auxiliary pump station and pipeline to move water from the Pecan Bayou at Riverside Park to the treatment plant. It was used while the main delivery system was being built along the route of the old canal, and retained to serve if the main delivery line is interrupted. The project was completed in April 1980 at a cost of $1,175,000.
The project to construct a new primary water delivery system between Lake Brownwood and the treatment plant was completed in November 1983 at a cost of $4,500,000. It's a combination gravity flow and pressurized system that spans just over 10 miles. The 42-inch line drops to 36 inches near Highway 279 on the lake road. Three major laterals including the one supplying raw water to the City of Early branch off before the size is reduced.
Another $5,120,000 was authorized at the time for treatment plant renovation and expansion.