Meanwhile, snow continued melting in the Rockies and Lake Powell continued to rise rapidly. To delay having to use the spillways, the USBR installed plywood flashboards (later replaced by steel) atop the gates to increase the lake level. Even this additional capacity was exhausted; discharges through the left spillway reached , and the right spillway was opened to . At Lee's Ferry, the Colorado River peaked at , which was and still is the highest water flow recorded there since the dam was built. On July 14, Lake Powell reached elevation, a level that has not been exceeded since. Just as it seemed inevitable that the dam would fail, inflows fell and the dam was saved. Upon inspection, it was found that cavitation had caused massive gouging damage to both spillways, carrying away thousands of tons of concrete, steel rebar and huge chunks of rock.