A few Sundays ago I was approached by a young girl who wanted to do a science fair project. She thought maybe she could test the water in the creak near her house. She was going to look at the water under a microscope and compare what she saw to tap water. I suggested a few refinements, including expanding her testing beyond critters in the water to some water chemistry, like temperature and pH, and observing the biological and physical environment of the creek.
In that moment, I saw a future creek monitor. I imagined this energetic girl, who had already had success raising money to purchase and preserve 8 acres of wildlands near her house, as the leader of a cadre of young volunteers, keeping track of the health of the forest and streams above her neighborhood.
I imagined her in a life of volunteerism. I volunteered as a young girl, too, doing good, taking care of my world. And maybe that is why I am an optimist and lifelong volunteer who works to make things better. Volunteering reverses the feelings of helplessness and hopelessness that plague us as we grow from youth to adulthood. It gives people a sense that they make their own communities. Volunteers are no longer passive receivers of the “government” but citizens. In this way, we make our communities whole. In this way, we keep our governments honest. In this way, we chose our future.
Now that the infiltration trench and bio-swale have been constructed, it is time to lay the sidewalk, which goes on top of the infiltration trench. How’s that, you say? Putting a sidewalk on top of the place where water is supposed to soak in? For the Paseo, we installed pervious concrete but even if we had used regular cement, it still would have worked as the system is designed to receive water from the bio-swale underground.
The Pervious Concrete Pathway winds its way from one end of the Paseo to the other, providing a pleasant and safe path. Pervious concrete has ‘voids’ or gaps that are created when the fines are removed from mix thereby allowing water to flow through the concrete. Water falling on or over the pervious concrete will flows through these spaces to the infiltration trench below it. To begin construction of the Pervious Concrete Pathway, a course of gravel was spread out over the infiltration trench and areas of the exposed impervious liner.
Unlike Portland cement concrete, pervious concrete sets up quickly. Many hands were needed to pour, spread, smooth, and score the concrete. The choreography of material and work was impressive that day and kudos to Rudy and his crew at J&M Contractors for a pathway many will enjoy.
To aide in the curing process and protect from errant soil or debris, the completed pathway was covered with plastic sheeting. Below you see the completed pervious pathway along with one of the landscape boulders.
Next up is construction of the Forebay, an important element of the design to protect the bio-swale from erosion and clogged soil.
In Part 1, we showed the initial steps in constructing the infiltration and bio-swale. Part 2 illustrates the complex choreography of marrying the infiltration trench and the bio-swale.
The majority of water entering the Paseo will be directed to the bio-swale, which will filter and allow water to infiltrate the soil and migrate to the infiltration trench. To maintain the function of the infiltration trench, we need to prevent soil from the bio-swale from filling in the voids and gaps. A geotextile – a tightly woven material – both helps prevent soil from moving into the infiltration trench and allow water to move into the trench.
The crew placed a layer of geotextile on top of the base layer of gravel and marked it to indicate where the edges of the infiltration trench and the bio-swale met. One side will have soil and the other will have gravel.
The challenge when backfilling the trench with gravel and the swale with soil is to maintain the vertical edge of the geotextile. To achieve the vertical profile of the geotextile, the crew placed plywood on edge to create a vertical guide. On one side of the plywood, a course of bio-retention soil was placed, then the geotextile that lay in place on the trench was “flipped over” the plywood guide to ‘cover’ the bio-soil layer and a course of gravel was spread out, then the geotextile was ‘flipped over’ the course of gravel and a layer of bio-soil spread out.
This sequence continued until the heights of the bio-soil and the gravel met the desired elevation points. The crew started in the center of the Paseo and worked out toward either ends of the Paseo. Kudos to the Paseo’s Field Superintendent Jose Esquivel, American Landscape, who masterfully choreographed the complicated logistics required for the delivery of gravel and soil and the work of spreading the materials.
Imagine living next to a blighted alleyway. You’d like to use it to walk to church or school or the bus stop, but it’s unsafe and ugly. This is the situation that used to exist in the Elmer Avenue neighborhood. Step one was just cleaning up the Paseo so people could use it again – getting the abandoned cars towed, adding a light, and painting over the graffiti. Thankfully, the City of Los Angeles took the first step in making the Elmer Paseo a safer walkway back in 2009.
But, the Paseo still flooded, making it unusable and unsafe many days of the year. This year, the Council for Watershed Health took the next step.
In October, out came the asphalt paving and in went the construction crew to begin excavation for a new Paseo that will capture between 1.3 to 1.9 million gallons water annually, provide a safe and comfortable pedestrian connection to local goods and services, reduce localized temperatures, attract birds and butterflies, and raise community awareness about their local watershed.
Could one of the most densely populated areas in the US see national park rangers in its recreation areas someday? For the last six years, the National Park Service has been studying just that question, and today they released the Draft San Gabriel Watershed and Mountains Special Resources Study and Environmental Assessment, a long name for a long process. The NPS started this study in 2005 after passage in 2003 of a bill by Representative Hilda Solis (companion bill by Senator Boxer).
Now we have the findings of the study:
First, the natural and cultural resources of the San Gabriel Mountains and Puente-Chino Hills are nationally significant.
Second, the study area is suitable for inclusion in the national park system because it represents natural and cultural resource types that are not already adequately represented in the national park system or protected by another land managing entity.
Third, the NPS determined that a collaborative partnership-based park unit would be a feasible addition to the national park system. A large traditional national park unit, owned and operated solely by the National Park Service, is not feasible.
And finally, NPS management in partnership with existing agencies and organizations is the best option for enhancing protection of significant resources, for improving access to recreational opportunities in the region, and for providing coordinated interpretation and education about significant resources.
How would this be implemented? The NPS looked at four alternatives and this is the one they liked best (quoting from the report): “Alternative D: San Gabriel Region National Recreation Area (A Partnership Linking Significant Resources and Recreation). In this alternative, Congress would designate a larger scale national recreation area that would recognize and protect the significant resources associated with the San Gabriel Mountains and Puente-Chino Hills, explore opportunities to protect and enhance interconnected ecosystems, provide important open space connections for recreation, and offer new educational and interpretive opportunities. … The NPS would take a lead role in management of the partnership, particularly in the area of interpretation and education.”
What are the next steps? The NPS is holding a comment period through December 16, 2011 with public meetings around the region. Then it will be up to us – and Congress – as to whether any of the recommendations in the study get implemented.
In these dog days of summer, its nice to see a fresh new video from NRDC on “stormwater runoff 101.” Starting with the end in mind, NRDC shows how people can do simple things to keep rivers, beaches, and oceans clean. I also like the video because they feature Elmer Avenue as an example of doing things right.
That’s what some people are calling the new green street retrofit – I guess because the swales look like little canals. Or maybe it’s because the street is just so pretty right now, after the plants have been in the ground for a couple of months. Emily Green, LA Times, calls it “The Dry Garden,” and Sunset Magazine’s Fresh Dirt blog says it is “a model, we hope, for the future.” I like the Mother Nature Network blog’s headline, “Elmer Ave. in Sun Valley, Calif., is ready for stormy weather.” You can read the most complete coverage on LA Creek Freak in the piece that has generated the most comments of any posting I’ve seen so far, “Elmer Avenue Green Street Project Explored.”
In case you haven’t been able to get out to see the street yet, here are a few more photos from earlier this month.
The plants in the swales are growing and blooming so well; I’m looking forward to seeing how they weather the summer heat.
I can’t give the residents enough credit for having the vision and grace to allow their street to become this showcase for all of Los Angeles, for how we can turn our streets and yards into gardens that harvest the rain.
Department of Water Resources Director Mark Cowin said “While the increase in deliveries is good news, we will continue to have a water supply crisis until we improve our conveyance system, increase storage and resolve the complex environmental problems of the Delta.”
Solutions? We need to use water, of course, but we are also victims of engineering. The system is designed to direct good rain into storm drains and send it to the ocean, bypassing the soil and groundwater basins. This way we lose enough water every year to supply over a million people. In the words of Dorothy Green, we need to unpave LA!
By turning yards into rain gardens and streets into water recharge facilities, we can ensure we have enough clean water for the future.
We took a small step in that direction with the completion of Elmer Avenue this May. Elmer recharges 16 acre feet a year, which is enough water to replace that used by residents of the street plus a few more households. Plus with their new drought tolerant and native landscaping and education about water conservation, we expect the residents will be using even less water into the future.
We don’t have enough parks in Los Angeles. Given the expense of land and the reality of built-out cities, we need to think about how we can create more parks in urban areas. We need to be creative in converting even small scraps of vacant land into places where people can enjoy nature, walk their dogs, and play. Almost five years ago a small group of people in Altadena got the idea to turn a small barren bit of dirt into a park for the community. Just 8,000 square feet and owned by the County’s Roads Division, the parcel was too small to be a true park. Also working against it, the land was on the border of Pasadena and Altadena – in the unincorporated County but with water from Pasadena. But this neighborhood had no park and thus the idea was borne – why not create a “pocket park?”
The design included native, drought-tolerant plants designed to bring the mountains into the city, and dry wells to collect and percolate all of the rainfall, eliminating sheet flow runoff from the site.
Several more grants and lots of hard work later, the hard, barren ground is blooming. We wanted to demonstrate low-water use gardening that people could replicate in their own yards. The park was completely a volunteer, community-led project from start to finish. It would not have happened, however, without the support of Supervisor Michael Antonovich and Metropolitan Water District. Mountain View Cemetery, Foothill MWD, Pasadena Water & Power, plus the members of Neighborhood Church were also major supporters. The list of supporters is long.
Here are a few more photos of the park, which is at the intersection of Marengo and Woodbury. We named it “Old Marengo Park” to acknowledge its origin as left over land when Pasadena and the County aligned Marengo Avenue. What neglected scraps of land can you turn into a park in your neighborhood?