California water managers are warning of the potential for spring flooding, as the massive Sierra Snowpack begins to melt. Chief Snow surveyor Frank Gehrke took the measurement Thursday at Lake Tahoe’s Phillips Station and manual readings found the snowpack’s water content at 183 percent of normal. Electronic monitors show the Sierra measures at 164 percent. It’s the most densest spring snowpack since 2011. The Sierra Supply provides about one-third of California’s water.