The storms that have pummeled Morgan Hill and the South Bay since last Friday brought plenty of traffic hazards and headaches, power outages and flooding on roadways and private properties throughout town.
While neighborhoods in some communities to the south—notably Gilroy and Hollister—saw vast power outages, residential evacuations and emergency rescues due to the flooding, Morgan Hill seems to have escaped more than 8 inches of rain over a five-day period with no major widespread damages or injuries.
The good news is that this season’s rainfall has already surpassed the annual average for this area, which is a hopeful sign that local water supplies will be plentiful this summer, according to Santa Clara Valley Water District officials.
“These storms are providing natural recharge and are helping to fill our reservoirs, which will certainly have a positive impact on groundwater supplies,” said SCVWD spokesman Marty Grimes. “In 2016, our groundwater storage improved significantly due to the community’s efforts to reduce water use (during the last four years of drought) and above-normal groundwater replenishment by the water district.”
Almost all of the district’s 10 reservoirs were at or exceeding capacity as of Jan. 11, according to the SCVWD website valleywater.org. The district’s largest reservoir—Anderson Reservoir in Morgan Hill—has to stay below about two-thirds of its full capacity due to seismic restrictions imposed by the state’s Division of Dam Safety. At times during this week’s storms, the release pipe at the bottom of the dam was releasing water at full blast into Coyote Creek, creating a dramatic gush of rapids into the northerly flowing waterway.
Precipitation is also above average statewide, another encouraging sign for local supplies because the water district—a wholesale water supplier—relies on sources in other parts of the state to serve nearly 2 million residents and businesses in Santa Clara County. The SCVWD’s allocation so far this year from the State Water Project—a network of water sources and storage facilities that provides water for numerous participating agencies—is about 45 percent of the annual total, Grimes said. That’s up from about 15 percent the same time last year.
But Grimes cautioned it’s still early in the rainy season, and the district will not know what the final allocation from the SWP will be until early spring. Thus, the district is not in a hurry to ease back on water-saving restrictions put in place at the height of the recent four-year drought.
“If February and March are bone dry, all of these ‘above average’ indicators could fall to average or below average,” Grimes said. “That’s why we are cautious about prematurely ending our call for drought response efforts or reductions.”
Wet January
According to Chris Henry, a local weather enthusiast who runs the “Morgan Hill Rainfall” page on Facebook, the series of storms that started Jan. 6 dumped nearly 9 inches where he takes measurements in southwest Morgan Hill. Sunday, Jan. 8, saw the worst of it, with 3.36 inches. Tuesday evening’s storms walloped Morgan Hill again with another 2.53 inches of rain.
So far in January, Morgan Hill has already seen 12.67 inches of rain, according to Henry. For the 2016-17 rainy season thus far, Henry has recorded 25.26 inches, which is about the annual average.
Morgan Hill Police and city staff issued numerous warnings via email and social media about road closures, downed trees, power outages and flooding during the peak of the rainfall this week. West Little Llagas Creek spilled over its banks Sunday night—flooding the downtown—and threatened to do so again Tuesday.
Both Sunday and Tuesday evenings’ storms placed the entire county under flash flood warnings. Residents and business owners frantically gathered sandbags at locations throughout town where the free supplies were available.
Social media users posted photos and videos of flooding at Nordstrom Elementary School and the nearby Nordstrom Park on East Dunne Avenue. Some Facebook photos even showed residents floating down the flooded streets in paddleboats.
Flood protection on the way
The flooding in this week’s storms serves to some as a reminder of the need for the water district’s Upper Llagas Creek Flood Protection project. When complete, the nearly 14-mile long, $80 million project will provide 100-year flood protection for properties from Buena Vista Avenue in Gilroy to just beyond Llagas Road in north Morgan Hill.
The flood protection project has been in the pre-planning stages since the 1950s, but a report by SCVWD to city staff in November 2016 stated that planning is done and construction on the first of two phases can begin this summer.
The project relies heavily on funding from the U.S. Army Corps of Engineers, not all of which has materialized. Local sponsors SCVWD and the City of Morgan Hill have fronted local funds to complete the planning and design processes, in hopes of being reimbursed by federal authorities in the future. The water district is also still in the process of acquiring private properties needed for the project’s right-of-way.
“When that project is completed it will remove the flooding problems in the West Little Llagas Creek corridor that have continually plagued the city,” Morgan Hill Public Works Director Karl Bjarke said Jan. 10.
The “most immediate” benefits of the flood control project will be seen in neighborhoods near the intersection of Hale and Wright avenues, downtown Morgan Hill, the Bisceglia/Monterey neighborhood, the La Crosse area and the Monterey/Watsonville Road intersection, Bjarke added. The latter of these was underneath two feet of water at one point Jan. 8, during the peak of Sunday’s afternoon storm.
“This flooding we are experiencing is the reason the city council and the Santa Clara Valley Water District Board reps meet quarterly (or more often as needed) and remain focused on completing” the local flood protection project, Bjarke added in an email.
The Upper Llagas Creek Flood Protection project will widen and expand the creek by digging large channels and installing culverts and tunnels that will capture the runoff from large storms such as those that drenched South County this week.
The project will not prevent flooding that occurs during heavy rains in eastern Morgan Hill, Bjarke noted.
The National Weather Service website, forecast.weather.gov, shows more rain is likely Jan. 12, but mostly sunny and clear through the coming weekend in Morgan Hill.
