Wet Winter Boosts Phoenix Reservoirs

Feb. 27, 2019

The Salt River Project estimates the Salt and Verde river reservoirs will reach 70% capacity by the end of the runoff season

The wet winter’s snow and rain accumulation has provided a much-needed boost to Phoenix’s water supply. According to the Salt River Project (SRP), the Salt and Verde river reservoirs will fill to 70% capacity by the end of the current water runoff season, which runs from approximately January to May.

The wet winter will provide a significant increase from water levels gained in 2018. On May 31, 2018, the reservoirs had only reached 56% capacity, reported AZ Central. Last year, the SRP’s reservoir system received 100,000 acre ft of runoff between Jan. 1 and May 31, yet earlier this month the entire system received 108,000 acre ft of rain runoff.

“There is no doubt that the Phoenix area is in much better condition than last year,” said Charlie Ester, manager of surface water resources at SRP.

Recent storm brought snowfall to the White Mountains in northeastern Arizona and other areas where melting snow contributes to the city’s water supply. Beyond snowfall, a series of storms in the wet winter brought heavy rainfall to the Salt and Verde river watershed. However, the last time SRP’s reservoir system was at full capacity was in 2010.

Additionally, as of Feb. 15, Arizona’s snowpack is 418% more than what it was last year on the same date. The current snowpack is also 38% higher than the 30-year average, according to the National Resources Conservation Service which calculates snowpack density by measuring depth and weight. The increased snowpack bodes well for Arizona’s water supply.

"This will help fill up the reservoirs," said Travis Kolling, water supply specialist at the agency’s Arizona office. "Good snowpack, good precipitation and soil condition is in good shape. All things are pointing to good (when it comes to) filling up reservoirs to more reasonable levels."

In addition to improving the state’s water supply, a slow melt of snowpack can improve wildfire season and limit risks.