BY PAUL HERZOG
A private water retailer named California American Water (Cal Am) approached theSurfrider-San Diego Chapter’s Ocean Friendly Gardens Program about helping turn a water guzzling area of a park and its runoff producing parking lot into an example of an Ocean Friendly Garden. Cal Am provides water to the Park. Patrick Pilz, Cal Am’s Field Operations Manager, is familiar with Surfrider: he is part of a team implementing a state grant-funded sustainable landscape program, and the team includes Surfrider, another non-profit, and several government agencies such as the City of San Diego. The Chapter jumped at the chance to do a project at such a high profile, public space. They had already helped successfully retrofit half-a-dozen residential landscapes in their region over the past five years.
Water had been running off parking lot to the street, down a storm drain and directly to the ocean, carrying all pollutants along with it. The nearby turf grass was continuously watered to keep it alive. The vision was to cut a curb surrounding the parking, directing rainwater runoff into approximately 2,000 square feet of turf grass that would be removed and replaced with a swale and basin plants with natives.
The public was told about the project and encouraged to participate when they attended a California Friendly Landscape Training – a class hosted by Cal Am, taught by Surfrider partner G3/Green Gardens Group, and which promotes OFG-oriented principles! The retrofit of the park was accomplished through a series of G3-ledHands-On Workshops (H.O.W.) as well as site prep by the City Park’s Department.Diane Downey (G3’s San Diego Regional Coordinator) and Jeremy Sison (G3 certified pro, and landscape architect) are both Surfrider-San Diego OFG Committee members (pictured above, left of the pole). Surfrider-San Diego Committee members also helped publicize the class and HOWs, and Cal Am created a cool all-in-one flyer for the events. Cal Am took care of H.O.W. registration and food for H.O.W. volunteers.
At the H.O.W. on Site Evaluation, participants analyzed the site’s “health” and where to apply CPR: Conservation potential, ways to improve Permeability and strategies for Retention of water onsite. They learned that a native garden needs just 20% of the water required by turf grass. Then the group calculated how much rainfall runoff was available from the adjacent parking lot based on the area of the lot and the average rainfall (10-14 inches). There was more than enough to support a native garden. G3 also led the group through doing tests for soil type and drainage, and discussed types of supplemental irrigation such as drip.
Three weeks later, a 2nd and 3rd H.O.W. were held on the same day. The first H.O.W. covered rainwater capture as well as turf removal and soil building through sheet mulching and rain capture. The afternoon’s H.O.W. covered planting and irrigation. (The City Park’s Department had removed the grass and done rough grading, including digging a shallow detention basin.) Volunteers then completed the grading, removed and remaining grass roots, then added mulch, then installed plants.
Rocks installed at the entrance to the swale slow the flow of the water, allowing it to seep into the ground, where pollutants are filtered and water is absorbed for plants to tap into during dry months. (Once the native plants are established, they will not need supplemental irrigation from the City’s water supply.) The project team learned that the water was not infiltrating well enough, so afollow-up H.O.W. will be done on February 21, 2015, focusing on drilling a dozen holes (aka augering) in the basin, back-filling with compost tea and mulch, then installing water-loving plants (juncus) in the basin and muhlenbergia rigens (deer grass) the sides …and possibly creating some side channels.
Cal Am picked up the bill for the H.O.W.s as well as compensated the City to cover the materials and site prep. Additional funding came from the project qualifying for the regional turf replacement rebate of $2/square foot. A H.O.W. attendee got so inspired that she OFG’d her home landscape (at left).