Friday, April 28, 2017

GSR Project is Going Very “WELL!”

Check out the evaluation —WELLvolution, if you will, of the Regional Groundwater Storage & Recovery (GSR) project’s Linear Park Well Station.  

In April 2015, construction kicked off at the Linear Park site in South San Francisco. This particular well station involved drilling 620 feet and installing over 120 feet of pipeline. Construction challenges aside, after two years of hard work, the well station infrastructure and landscaping are complete. Now the team will focus on conducting extensive testing for the station to make sure the well is operational.  

Linear Park is one of 13 well sites nearing completion as part of the first phase of the GSR project.  It is anticipated that this phase of work will be completed in this fall. The project team is currently investigating three additional well sites as part of the next phase of this work. The entire GSR project is expected to reach final completion summer 2019.

     In July 2015, workers installed steel rebar to prepare for the wall pours at the
                                              Linear Park Well Station.

          One month later, August 2015, the wood and steel frames for the 
                                        well station were complete. 

      By July 2016, the concrete walls were built and the well pump was installed.

        By March 2017 the landscape has grown in and the site is almost complete.

About GSR

GSR includes the construction of up to 16 new recovery wells and associated facilities on the Peninsula. This project is the result of a landmark agreement between the SFPUC and City of Daly City, City of San Bruno and California Water Service Company to help manage the South Westside Groundwater Basin. In wet years, these entities will use Hetch Hetchy water in place of their groundwater supplies to allow the aquifer to store up to 20 billion gallons of water for use in times of emergency or drought.

Friday, April 21, 2017

Life on the Watershed: Lizards, Lyme Ticks and Us

They’ve been hibernating through winter, but the new clear weather is bringing out the sun-loving Western fence lizards--which happen to lower our risk for Lyme Disease. 

From grassland to brush and forest, we spot them basking on rocks, logs, trail-side benches, and other open areas—where they can be easy prey for certain birds and small mammals. But the native reptile has protective devices too, like quick reflexes and the ability to scurry quickly into a crevice or other shelter. It can readily discard its tail to get away--and the tail will grow back.  
Spring is mating season, when males establish and defend a territory. The "push-ups" we see them do are indicators of another nearby male, or a female. Females lay eggs, which hatch in mid- to late summer.

Western fence lizards eat spiders and insects. In turn, they are favorite hosts for tick nymphs--and that's a good thing for us.

It turns out that Lyme disease (carried by a tick species called the deer tick) is much lower out here in Western fence lizard country. That's because there's a particular protein in the lizard blood that permanently kills off the Lyme-causing bacterium inside the young insect, So only a small percentage of adult deer ticks are Lyme carriers.


Thursday, April 13, 2017

Easter Wildflowers on the Watershed

Areas of serpentine soil are currently yielding a profusion of native wildflowers along the Peninsula Watershed ridges.

Serpentine soil is derived from California’s state rock—the greenish metaphoric serpentine rock originating from the earth’s mantle. Serpentine rock outcrops are closely associated with California fault lines. The soil is high in magnesium and iron, but low in calcium, aluminum, and nutrient-rich clay, so that it is thin and inhospitable to many plant types. Its plant communities are typically composed of stubby, low-growing native grasses and small herbaceous plants.

Conversely, serpentine soil attracts a variety of native wildflowers—many of them rare or endangered—that thrive in the extreme conditions so unfavorable to many of their more common or non-native competitors. To check out this year’s serpentine displays on the Peninsula Watershed, join a guided hike or bike ride along the Fifield-Cahill Ridge Trail.

Friday, April 7, 2017

Life on the Watershed: Nesting Season Under Way

The Peninsula Watershed is home to an abundance of diverse native birds and, after the rainiest winter in decades, spring nesting season is now under way. 

The wet weather has caused some of the hawks and other larger species here on the Peninsula to hold off a little longer than usual this year. But smaller songbirds have begun to nest, and the  tiny iridescent Anna’s hummingbirds are some of the first.   

The roughly 2-inch-diameter hummingbird nest, deep in the  greenery of trees or shrubs, is made of such materials as plant fibers, downy feathers and animal hair bound together with spider silk. Tufts of lichen woven into the exterior help to camouflage it from predators. It’s the female who builds the nest and raises the young alone, without assistance from the male.

For the most part, Anna’s hummingbirds are year-round residents. Their high-frequency wing beat allows them to hover by one flower, gleaning the nectar with a long thin bill—and even longer extendable tongue—before they dart off to the next flower, and the ones after that,  pollinating as they go.