Llano staff recommend dam improvements, dredging and new storage permits to shore up water supply

City staff presented a package of options July 1 to increase the city’s firm water supply, saying the proposals would involve new permitting, engineering and major capital costs. The discussion covered continuing dredging and bathymetric surveys, temporary “flashboards” to raise existing dam heights, potential dam‑raising work, a new off‑channel reservoir or a third dam, and the need to add storage permits with the Texas Commission on Environmental Quality (TCEQ).

Why it matters: The city’s two existing storage permits total about 700 acre‑feet (383 acre‑feet for Towne Lake under a 1914 permit and 317 acre‑feet for Robinson Park under a 1956 permit). Staff said recent bathymetric work showed both gains and losses in stored volume since 2011 and that raising dam heights or building new storage would be the most certain way to increase available water. The proposals, staff said, also open access to grants and water‑contract opportunities but require long lead times and substantial upfront work.

City staff summarized recent storage surveys and dredging outcomes, showing that combined stored volumes rose between 2011 and 2022 but declined slightly in a 2025 survey. Staff said Towne Lake’s storage when measured in 2011 (without flashboards) was about 272 acre‑feet; adding flashboards increased Towne Lake…