It’s been about two weeks since it rained in Morgan Hill, and
minus a brief cool-weather system that’s expected to roll through
this weekend, the blue skies and dry days are here to stay through
the remainder of the season.
It’s been about two weeks since it rained in Morgan Hill, and minus a brief cool-weather system that’s expected to roll through this weekend, the blue skies and dry days are here to stay through the remainder of the season.
That means the city of Morgan Hill will likely be asked to cut overall water use by 20 percent until supplies grow. Residents may soon be prohibited from using water hoses to wash their cars, forced to shut off landscape irrigation during the day, and banned from cleaning driveways and patios with water.
According to National Weather Service forecaster Brian Tentinger, most areas in the south San Francisco Bay area have received about 80 to 85 percent of the normal rainfall expected at this time of the rainy season, which runs from October to April.
A brief storm this weekend is expected to bring cooler temperatures and drop a half-inch of rain, at the most, on Morgan Hill, and Tentinger said that will likely be the last significant precipitation event of the year.
“Things are winding down right now,” Tentinger said. “Based on the models we have now, it looks pretty dry after this system goes out.” He added it is “typical” every year for the weather to dry up as the end of the season approaches.
As a result, it is unlikely that rainfall will reach normal levels by the end of next month, Tentinger said.
Normal annual rainfall in Morgan Hill is about 24 inches, and to date slightly more than 15 inches have fallen this season.
The Santa Clara Valley Water District board of directors is expected to recommend mandatory conservation to the retailers and 1.7 million customers it sells water to throughout the county. The board will consider calling for “mandatory conservation” by 20 percent at its meeting Tuesday.
Board Chair Sig Sanchez said “not much has changed” since the board first discussed the possibility of such restrictions in February, weeks before a series of storms brought more than eight inches of rain to South County.
Even though March rains and the resulting runoff from the hills raised local reservoir levels by about 20 percent, the district’s concern is a cut to its imported water supply.
“My guess is that we will impose mandatory conservation. Our imported water supply doesn’t look any better than it did several weeks ago,” Sanchez said.
Water officials began discussing the prospect of mandatory conservation in February due to the ongoing statewide drought which is in its third year, and has affected both local and imported water supplies.
District spokeswoman Susan Siravo said even if all the district’s 10 reservoirs were filled to capacity, that wouldn’t be enough water to supply local water needs. She said the current levels in the local reservoirs, about 65 percent of capacity, is “fairly strong” for this time of year. In January, the reservoirs were at about 45 percent of capacity.
“But reservoirs are just one part of the equation,” Siravo said. “We can’t survive on local water alone.”
The district typically relies on water imported from other areas, such as the San Joaquin River Delta, for about half of its needed supply. This year, the supplies of water available to Santa Clara Valley from its usual outside sources have been slashed by about two-thirds, Siravo said.
Thus, this year the SCVWD will rely more than it ever has on a vast groundwater basin in southern California to supply local customers. Siravo has said that water costs more than other imported water because it has to be transported such a long distance.
Morgan Hill Environmental Programs Director Anthony Eulo said the city will institute its urban water management plan if the district board asks them to conserve 20 percent. The plan is required to be up-to-date by all 16 of the cities served by the district, which sells water wholesale to the retailers, who then sell water to their customers.
“The city recognizes water is in limited supply during this dry time, and we’re prepared to act in response to the district’s action,” said Eulo, who presented a staff report outlining the city’s water conservation plan at a city council workshop Wednesday night.
The contingency plan the city will likely adopt in response to the SCVWD’s call will include limiting some residential uses of water such as car and boat washing, cleaning outdoor patios and driveways, and the use of decorative fountains that don’t recirculate water.
The last time the water district called for mandatory conservation was during a drought in 1989, when they asked customers to cut their water use by 25 percent. They didn’t lift the restrictions until 1992.
Local weather observer Chris Henry said the rain expected Saturday and Sunday won’t be enough to run off into the reservoirs. He said the land in the hills has dried up since the last storm earlier this month, and the half-inch or so that could fall this weekend will merely soak into the soil.
Tentinger added that after the system passes through this weekend, temperatures will steadily climb up to the low 70s by the end of next week.
