In March, lakes Travis and Buchanan – the region’s water supply reservoirs – rose with above-average rainfall and inflows into the Highland Lakes. March inflows were 121,869 acre-feet, about 136 percent of the monthly average. The March 2016 inflows were the 15th highest inflows for the month since 1942. Inflows are the amount of water flowing into the lakes estimated from measurements at four gauges upstream.
Lakes Buchanan and Travis together rose from 90 percent of capacity on March 1 to about 96 percent of capacity on April 1.
In March, lakes Buchanan and Travis reached their highest levels in years. Lake Buchanan reached 1,015.9 feet above mean sea level (feet msl), or 90 percent full, the highest elevation for the lake since July 2008. Lake Travis hit 681 feet msl – 100 percent of the lake’s capacity for water supply purposes – for the first time since May 2010. But even when full for water supply purposes, Lake Travis can capture and hold an additional 787,000 acre-feet of floodwaters in its flood pool.
During floods, LCRA operates the Highland Lakes dams to protect Austin and reduce flooding impacts from the Colorado River on communities downstream of the lakes. Lake Travis is the only lake in the Highland Lakes chain specifically built to hold floodwaters.
In addition to managing floods, the Highland Lakes also were created to capture water when it rains to ensure the region has a reliable water supply during dry times. Lakes Travis and Buchanan provide drinking water for more than a million people and water to industries, businesses, the environment and agriculture in the lower Colorado River basin.
"LCRA manages the Highland Lakes and the lower Colorado River as a system," said John Hofmann, LCRA executive vice president of Water. "Our job is to balance the stakeholder interests, and urge all of our customers to use what water they need, but not to use more than they need."
LCRA regularly moves water downstream from Lake Travis to supply customer and environmental needs from Lake Austin to Matagorda Bay. Customers include municipal water systems serving Austin and west Travis County, power plants, farms and industries located near the coast. Environmental needs include requirements to maintain flows along the lower Colorado River and into Matagorda Bay.
LCRA is managing lakes Travis and Buchanan under a new state-approved Water Management Plan. In November 2015, the Texas Commission on Environmental Quality approved the updated plan, which better protects the water supply for firm customers – mainly cities and industrial users – and enables LCRA to more quickly adapt its operations as drought conditions change.
Under the 2015 Water Management Plan, up to 202,000 acre-feet from the Highland Lakes is available for diversion for first crop rice and turf in the Lakeside, Gulf Coast and Pierce Ranch irrigation operations. Additional interruptible stored water will be available to the Garwood Irrigation Division consistent with the Garwood Water Rights purchase agreement. If needed, water from the Highland Lakes would be released gradually over a period of months and only to the extent the needs for irrigation cannot be met with the natural flow of the Colorado River. Read a fact sheet and frequently asked questions on Highland Lakes water releases for agricultural irrigation in 2016.
Here is a link to the article page: Lake Travis fills up with March rain