But in San Luis Obispo County and some other parts of the state, precipitation has been close to average — bringing enough rain to be a welcome respite but far from enough to erase the four-year drought. Most of the county remains in the worst “exceptional” drought rating, according to the U.S. Drought Monitor, and appears likely to stay that way until at least next winter.
“This is the most rain we’ve had in five years, so it hasn’t been a complete bust,” PG&E meteorologist John Lindsey said. “But our county seems to be on the border of having good rain and not really great rain. It was great in Cambria and Rocky Butte, but as you head down into Nipomo the levels drop off big.”
For most areas of the county, February delivered less than an inch of rain, and March produced between 2 and 4 inches, according to a 30-day update of drought conditions presented to the county Board of Supervisors last week. Reservoir levels are also significantly lower than average capacity.
You just have such a small bit of time to get the storms to come down here and produce that rain. And we’re quickly running out of time.
John Lindsey, PG&E meteorologist
“One of the things we’re seeing is the drought has been so deep and the watershed is so dry that our reservoirs are not responding the way they always have,” San Luis Obispo County Public Works Deputy Director Mark Hutchinson said. “So we do all this careful work and it says based on the rain we had in January we should have seen (a certain) increase in lake levels — we saw nothing like that.”
One exception is Nacimiento Lake, which has a coastal watershed and didn’t dry out to the same degree as inland watersheds, like those feeding Lopez Lake and Santa Margarita Lake (Salinas Reservoir). Nacimiento, which was at 17 percent capacity in December, is now at 35 percent, and suppliers who draw water from the reservoir will receive their full allocations.
Another bit of good news is that the state has increased its water deliveries estimate to 45 percent from 10 percent, meaning the water suppliers in the county that receive state water would get their full allocation this year. Despite that, the Pismo Beach City Council decided last Tuesday to keep a building moratorium in effect.
Lindsey said storms that started Friday and are expected to continue into Sunday are expected to produce between 0.40 and 0.95 of an inch, with a stronger low-pressure system to move through the Central Coast on Wednesday night into Thursday with periods of moderate to heavy rain and thunderstorms. The wet pattern could return the following week.
“Two or 3 inches won’t probably do a whole lot for the reservoir totals, but it will certainly increase the seasonal rainfall,” Lindsey said. “I think Lopez probably won’t go up much but Lake Nacimiento will probably go up a bit more.”
Even with more storms predicted in April, the window for the county to receive any more significant rain is closing.
It would take a record rain season along the Central Coast to erase the four-year deficit — about 55 inches of rain at Cal Poly, for example. The all-time record for Cal Poly is 54.5 inches, which occurred in the 1968-69 rain season, Lindsey said. So far this season, Cal Poly has received about 19 inches of rain.
“You just have such a small bit of time to get the storms to come down here and produce that rain,” he added last week. “And we’re quickly running out of time.”
Message to conserve continues
The message to San Luis Obispo County residents is simple: Keep conserving.
“We need to stay the course and do what we’ve been doing for the last two years,” Hutchinson said. “I think the folks here in San Luis Obispo County are very much aware of what the water situation is in their community. It’s just been so much less than what we thought we might get.”
Cities and communities across the county adopted water use restrictions in 2014, and statewide mandatory water conservation measures intended to cut water use by 25 percent took effect last spring. Outdoor watering to county service areas in Cayucos, Santa Margarita and Shandon was cut to two days per week last summer, for example, and remain in place.
County officials have also been taking steps to increase the resiliency of some of their small water systems, which are vulnerable to drought because most rely on single water sources. In Shandon, which receives drinking water from two wells, construction to hook the community up to the State Water Project should be complete July 7.
Santa Margarita, which also relies on wells for drinking water, has been on an “alert” drought status for some time. But a 2.5-mile pipeline project has been completed to supply the town with emergency water from Atascadero Mutual Water Co. if needed.
We need to stay the course and do what we’ve been doing for the last two years.
Mark Hutchinson, SLO County public works deputy director
Last year, in anticipation of Lopez Lake falling below 15,000 acre-feet — it’s now at 14,637.5 acre-feet — water deliveries were cut 10 percent to communities that receive drinking water from Lopez Lake: Arroyo Grande, Avila Beach, Grover Beach, Oceano and Pismo Beach.
The lake can hold 49,388 acre-feet. An acre-foot is equal to 325,851 gallons, or enough to generally serve about three households per year.
If the lake falls below 10,000 acre-feet, which could happen this fall, municipal deliveries would be reduced another 10 percent but downstream releases would be cut 75 percent, Hutchinson said. That would mean a substantial reduction for farmers who depend on the water in the upper Arroyo Grande Valley.
Brian Talley, president of Talley Farms, pulls water from wells close to Arroyo Grande Creek to irrigate some of the family owned farming company’s crops. In the past couple of years because of the drought, the owners have left more ground fallow and generally eliminated a pre-irrigation practice to reduce weeds by germinating them and then tilling them into the soil.
Now, Talley said, he and his partners, two cousins and his mother, need to discuss how they might adjust their planting schedule if faced with reduced water deliveries in the fall, or even earlier over the summer. They’re just now gearing up to plant their biggest crop, green bell peppers, which are harvested in mid- to late August through about Nov. 10.
“We have a planting schedule to plant bell peppers and if there’s an expectation that they’re going to reduce the amount of water coming down the creek, are we going to adjust our planting schedule accordingly?” he said. Right now, the answer is unclear.
Other drought impacts
The drought has left casualties in its wake. Thousands of trees have died, county officials said — live oaks of all shapes and sizes and Cambria’s landmark native stand of Monterey pines. In Cambria, mortality rates range from 40 percent to more than 90 percent depending on whether the figures relate to the entire stand or a specific neighborhood or area.
Hundreds of dead trees are poised to fall on homes, vehicles and infrastructure, according to the county’s April drought update. Fifteen trees fell in less than three hours during a Jan. 31 storm, The Cambrian reported.
And the eucalyptus stands on the Nipomo Mesa are showing an increase in the number of dead trees and the number of live trees with dead crowns, which increases the amount of dead fuel available for fire.
Though the winter storms have reduced the potential for large fires, county officials expect to see vegetation fires starting by mid-April if the area doesn’t receive significant rain. Warm sunny weather that followed some of the storms prompted an abundant grass crop, which could fade with extended periods of dry and windy weather, increasing the potential for early season fires.
Cal Fire, which is at winter staffing levels, has been training new firefighters and plans to increase staffing to 10 wildland engines on Monday.
According to the drought update: “More frequent and faster spreading grass fires are likely in 2016.”
San Luis Obispo County Precipitation Totals
Rainfall data from July 1, 2015, to March 31, 2016, compared with historical average rainfall during the same period (July 1 to March 31).
Average rainfall, July 1 to March 31 (inches)
Actual rainfall, July 1, 2015 to March 31, 2016
Percentage of average rainfall
Diablo Canyon Ocean Lab
Paso Robles Municipal Airport
San Luis Obispo, Cal Poly station
Sources: Western Regional Climate Center, Cal Poly Irrigation Training & Research Center, PG&E Meteorologist John Lindsey