Luis Barranco, the UC Landscape Architecture and Environmental Design Department's financial assistant is also a Koi fish expert. He agreed to help us test water samples in the garden to determine the waters' content. We are discussing whether it would be wise to pump water from a seep from the Australian hollow to higher elevations in the garden to feed the pools which contain fish and possibly use as irrigation.
2 weeks ago, we spent just one hour collecting trash out of Cerrito creek which runs through the south side of the garden. Pictured is a sample of what we found and prevented from washing into the bay. We hope to design and construct a weir at the top of the creek to capture the trash that we don't collect by hand. [caption id="" align="alignnone" width="307" caption="Click on image to download PDF (2.9mb)"][/caption]
Blake Garden has been keeping rainfall records since 1965. In the short video posted below garden manager Lauri Twitchell measures and records rainfall using the simple rain gauge installed at the garden. [media id=2 width=320 height=240] California is currently in a state of drought. Although the rainfall recorded at Blake Garden recent years hovers near the Bay Area Yearly average of 26 inches, it is important to note that other regions in California (such as the Sierras) are falling far short of the necessary averages. Another point to keep in mind is that from 1965-2009 the Bay Area population has doubled from 3.6 million to 7.3 million. This population growth has been accompanied by tremendous residential and industrial development that has added further demands on water usage and consumption. At Blake Garden efforts are being made to conserve water and reduce consumption. These efforts include: rainwater collection, greywater reuse, mulching and composting, cistern collection from on-site seeps and creeks, native drought-tolerant plantings, lawn reduction and irrigation redesign. BLAKE RAINFALL CHARTS & PDS INDEX LINKS: Blake Garden Rainfall Chart 1965-2009 pdf file Bay Area Population Census Long Term Palmer Drought Severity Index for July 2009
During the month of April work has been done to repair a leak in the 1500 gallon cistern in Australian Hollow. The cistern was initially acquired by the garden in the mid 1970's during a drought and hooked up - at that time - to the seep under the parking structure. PHD candidate Kristen Podolak, LAEP graduate student Nathan Hodges, volunteer Peter Suchecki, and three students from ES 125 (May, Austin and Linda) fixed the leak and built a new foundation out of recycled sidewalk cement (donated by Mike Frappier) for the cistern. A zip line was rigged from the event lawn area to get the heavy cement blocks and mulch down to the cistern area. This past Monday the bamboo aqueduct that brings the water from the seep was hooked up to the cistern and it is filling once again. The garden is exploring solar pumping options to transport the water to other parts of the garden.
Students from Professor William Berry's ES 125 class, Environments of the San Francisco Bay Area, have been volunteering in the garden for the past few weeks to work on the creek project. We have been clearing the invasive blackberries and Algerian ivy and other invasive species from the creek area to study the creek channel, and uncovering and assessing an earlier bank renovation. As we are clearing we have been mulching the area to slow the regrowth of weeds and to add organic matter to the very heavy clay soil. We have also been removing years of trash and debris that has washed in and blocked the flow of the creek.
Mulch piles appeared from Expert Tree Service. They were pruning some Monterey Pines in the neighborhood and dropped off the chipped product for Blake to use as mulch in our efforts to conserve and retain water and to build the structure of the soil.
With generous support from East Bay Municipal Utilities District's Water Smart Program we redesigned the event lawn at the hub of the garden. We reduced our amount of turf grass and replaced it with a large area of permeable pavement and mulched beds planted with replacement plants consisting of drought tolerant species. We also replaced our inefficient irrigations system with new low water use irrigation systems.
The project was designed by a team of students, garden staff, volunteers and a professor from the Landscape Architecture department. It was built over 9 months by a large team of students, staff and volunteers.
The project was complicated to construct because of the site's popular location. It is centrally located on the property where there are views into other parts of the garden and also there is a stunning view of the bay and the Golden Gate Bridge. For this reason we wanted to keep the area open as much as possible during construction. We often got help and advice from neighbors and visitors when we encountered building issues as we were constructing the new lawn area.
The Landscape Architecture students taking a materials and construction class in the Landscape Architecture program are designing and building a bench to be included in the design. (See Bench Postings) [nggallery id=22] Download Project Sign PDF
The creek restoration project began about a year ago when we started removing Himalayan Blackberry bushes and Algerian Ivy from the creek bed and trees. The creek is an upper part of Cerrito Creek and is fed mostly by urban runoff when it rains. The creek fills at an alarming rate (see time lapse video). We wanted to see where this water was coming from, and assess the condition of the creek bed and creek bank. We soon uncovered a rotting bridge, an older restoration project done in the 1970's with retaining walls made of concrete bags, some pools that had been made, lots of chatter was strewn in the creek bed, some undercutting and erosion.
[nggallery id=12] PHD candidate Kristen Podolak and MLA candidate Jessica Ludy surveyed the creek that had been opened up by staff and volunteers to start to create a new plan for restoration. (download Kristen & Jessica's paper)
[nggallery id=11] Later Nathanial Behrends, Master of Landscape Architecture Candidate, from LA 227 Restoration of Rivers and Streams, after reviewing Kristin's work and evaluating the condition of the newly uncovered upper area recommended a series stepped pools for the creek to slow the water coming through the channel to decrease the cutting of the banks. (download Nathanial's paper)
[nggallery id=15] After more removal of berries on the upper part we then discovered the creek was blocked with silt and urban debris that was diverting it from the original channel and creating scouring and cuts in the upper part of the garden. We removed the debris and restored the water to the original channel. [nggallery id=13] A group called The Weed Warriors led by Susan Schwartz of Friends of Five Creeks came in recently to eradicate some of the blackberries. (view time lapse video of The Weed Warriors at work) As we clear more weeds from the creek new opportunities emerge.
An old seep exists under the parking structure just west of the event lawn. Peter, a volunteer has been developing an aqueduct system from the seep to feed into a large 1400 gallon cistern that is situated in the middle of the Australian Hollow. We will use the water to water a student "LIVING WALL" project that is being developed for the San Francisco Garden show display. The aqueduct is made from bamboo found on the property.