Where the water came from and where it went, at today’s rates. Dam releases and withdrawals have no complete public feed, so the last line is the leftover that makes the books balance — an inference, not a measurement.
USGS gauges, at current rates
Climatological estimate over 18,678 surveyed acres (TWDB)
Level trend since midnight, scaled to 24 h
The leftover that makes the books balance — arithmetic, not a sensor
The river leg is measured at a USGS gauge downstream of the dam — a proxy for releases. The balance leg is whatever the mass-balance residual can’t attribute: municipal intake, ungauged runoff, and estimation error. Legs can overlap conceptually; treat proportions as honest approximation, not gospel.
Live streamflow at the 5 river gauges (USGS + LCRA, freshest network), plus yesterday's average dam releases (LCRA). Labels show measured flow — line width is not to scale.
Inflow converts current streamflow at the USGS gauges to acre-feet per day (1 cfs ≈ 1.9835 af/day). Evaporation uses long-term monthly averages for the region over today’s lake surface — TWDB’s surveyed daily surface area where published, a geometric estimate elsewhere. Inches on the lake divides each volume by that same surface area, so an inch honestly costs less water when the lake is low and narrow than when it’s full and wide. Storage change scales today’s level change (vs. midnight, LCRA) to a 24-hour rate using an elevation–area approximation. The residual closes the balance and bundles dam releases, withdrawals, and ungauged runoff — inseparable without data the operator does not publish.
Early in the day (before ~3 a.m.) the storage trend is withheld to avoid wild extrapolation. All inputs are provisional; treat this page as an honest estimate, not an official accounting.