Manning Park 160 Acre Foot Stormwater Capture and Storage Pilot Project...
Oak Creek at East Valley Under cross, Montecito, California
Oak Creek undercrossing at East Valley Road. (1974 Army Corps est 600CFS or.. 4,488 gallons per second at this point in 100 year flood) This creek really produces, and it's all rock lined to this point at East Valley Road so it is a stormwater channel = no steelhead and cleaner water.
Manning Park Plan Here...
Geosyntec Groundwater Prop 1 Study Manning Park
Last year 2017, the County of Santa Barbara hired Geosyntec to complete a survey of locations and methods to save stormwater and re introduce that water to various aquifers in the county. The study was funded with $500,000 of Prop 1 monies from State taxpayers... Over 300 submissions were reviewed and only ten were selected for presentation to the County and public.
We at Cole Design Montecito are stakeholders in the study process and one of our design concepts was selected in the top ten. Manning Park is now one of the Geosyntec recommended groundwateter recharging projects. Selected pages from that study are shown below and the entire study can be seen at the view more button.
Geosyntec Version, Manning Park Plan Here...
SITE RAINWATER AMOUNTS
AND CALCULATIONS
Using the rainwater runoff that gathers in Oak Creek and the adjacent concrete drain chute at the corner of San Ysidro and E. Valley, we can gather more water than can be used in nearly five county parks. The watershed feeding these two points is 3,000' wide and about 7,000 deep. From East Valley Road and San Ysidro, about 1,500 feet wide, and nearly up to Camino Cielo at the top of the foothills.
One inch of rain produces about 11.5 cfs or, 86 gallons per second at this under-crossing. That is what is seen below. This is a one inch rain and this flow level lasts about 20 hours. Therefore ... 86 gps = 86 x60 x60 x24 = 7,430,400 gallons per day. That equals 22.8 acre feet per day flowing under the bridge at E Valley. The stormwater outlet at the corner also produces a similar amount of water, not counted here.
Two cubes at this site will gather at a minimum 12.75 gallons per second- Thus 12.5 x 60 x 60 x 24 = 10,080,000 gallons gathered in 24 hours from one cube. That's 3.314 acre feet. Four cubes will produce 13.26 acre feet per day per inch of rain. Thus with an average of 18" of rain, the capture number is 59.6 AF per year. We propose storing this water for a few days at most and send it upstream to irrigate parks and other lands adjacent the creek corridors.Thus adding to groundwater recharge.
Oak Creek at East Valley Road- 1/2" rain January 12 2017
Oak Creek is completely rock lined from E.Valley Road upstream several hundred feet. Therefore no fish, no creek excavations, fewer constraints on capture.
Oak Creek 400' below E Valley Rd. Jan 22 2017 4" rain
Collection and storage locations
To capture stormwater out of these storm-drains, instal two collection cubes in each spot shown above (4 cubes total). At the Oak creek East Valley road over cross, and at the storm drain exit just south of the corner of E. Valley and San Ysidro road. Place captured water into 12" pipes that are anchored or buried into the top of the creek banks. Follow the creek path down to Manning Park. Directly place captured water into a pre folding pond for silt removal, then over flow into main pond. Pump water into new pipe under San Ysidro road to additional reservoir on western wing of Manning Park.