THINK “WORLD PEACE,” “INFORMATION AGE,” “ICE CREAM” — “watershed management” may be a dry term, but few two-word phrases promise so much to so many.
L.A.'s water troubles, in brief: too little water in the L.A. basin, too much floodwater in the rivers.
Flood control — or L.A.'s approach to it, with concrete river channels and storm sewers — has made both troubles far worse. It drains water from across the L.A. basin and puts it . . . where? In the rivers. So floodwaters swell. L.A. has to import water. And water quality plummets, because pollutants wash straight into the rivers (to the ocean) rather than into the ground, where water self-cleans. In sum, it's an insane way to make the water go 'round in our beloved semiarid, flood-prone basin.
Watershed management would restore the basin's natural hydrology — to maximize water supplies and quality as well as flood protection. Such strategies as cisterns, wetlands, trees and permeable surfaces capture storm water where it falls, where we can recycle it right away or let it sink back into the aquifer. Far less water enters the rivers — and during floods, diversion basins and channels where necessary can contain the rest. And we get parks, wetlands, habitat and clean, low-cost water all over the place.
And then . . . some of the concrete can come out. Advocates disagree on how much, and how soon. Ten years? Fifty years? A little right now? Most agree that to dynamite concrete by the mile is a very long-term goal, but that we can connect enough of the river back to its watershed to restore the health of both. You don't have to remove every inch. In fact, advocates generally see the ultimate measure of a healthy L.A. River as the return of the steelhead trout.
Barriers to this transition include scarcity of available riverside lands (for wetlands restoration and diversion lakes) and a vast basin of impermeable pavement. But in the past year, a few armies' worth of public agencies and nonprofits have set out to collaborate on detailed watershed plans. In the surest sign of a revolution, L.A. County's Department of Public Works — long the Sun God of Flood Control — reorganized in 1999 to create a Watershed Management Division. And the engineers up in that tower in Alhambra are serious about it: They win raves on the many projects they're leading or helping out on. The studies will be complete in 2001°©2003. Land purchases and pilot projects, already under way, should multiply rapidly.
Let the transition begin! These are the first projects:
Upper watershed. The massive existing flood-control system includes concrete–channel tributaries, spreading grounds, and dozens of dams and detention basins in the uplands that drain into the river. Projects to restore the upper watershed to health include greening the diversion basins, removing exotic plants that either choke the channels or soak up unusual amounts of water (or both), and releasing floodwaters on a schedule that will enhance wetlands habitat downstream. The county is also eyeing sites to remove concrete.
Sepulveda Basin. The 2,000-acre detention basin behind the Sepulveda Dam — flooded only during unusually heavy rains — has doubled as a recreation area since the late 1950s, with wetlands restored in stages since 1979 (see The Valley). The Bureau of Sanitation wants to construct a 50-acre wetland, with plants that bind pollutants, to clean Tillman water to new state standards. In the multipurpose spirit of watershed management, the design makes the wetland a wildlife area with trails, bike paths and views. If it works, the bureau will construct 500 acres in all. (ETA start 2003) And the Army Corps of Engineers plans to restore a 28-acre chunk of habitat along Bull Creek, with trails and natural-history info. (ETA start 2002)
Tillman Water Reclamation Plant. The treatment plant, which cleans San Fernando Valley wastewater to a tertiary standard (wade in it, but don't drink it) and releases it into the river, is now actually the source of most of the river's dry-season flow — which means that, until L.A. can supply its own water, much of the river water originates in other watersheds.
Tujunga Wash. This 1-plus-mile greenway/bikeway will connect a major tributary back to the basin not by dynamiting the concrete, but by diverting water into a new, parallel streambed — see the Lower Arroyo Stream Restoration for a precedent. It's brought to you by the Santa Monica Mountains Conservancy, County Public Works and Zev Yaroslavsky's 3rd District, which would like to see the greenbelt in this park-deprived area expanded along the entire 9-mile wash. (ETA start 2002) The River Project, meantime, is doing a hydrodynamic model of the entire wash, to identify sites where concrete removal would be feasible. (ETA 2001)
Sun Valley — a microcosm of the future. In its first big commitment to Doing Things Differently, County Public Works scrapped a $42 million storm-drain plan and intends instead to manage this 8-square-mile mini-watershed according to the principles of sustainable watershed management. Key partners are TreePeople, which convinced Public Works it's possible, and Yaroslavsky's 3rd District office, which has rallied community support. The design — with retention lakes, cisterns in yards, trees, mulching, porous paving, asphalt removal — will set out to capture 100 percent of the storm water. It'll bring green space and good drainage to this park-poor, flood-plagued, predominantly working-class Latino area, and flood protection, cleaner air and water, energy savings, and more water to Sun Valley and communities downstream. If it works here, TreePeople founder Andy Lipkis says, “There'll be no way of stopping it.” It's 8 square miles with potentially huge consequences for the entire 834-square-mile watershed. (ETA 2011. A concrete storm drain would take eight years.)
T.R.E.E.S. TreePeople's remarkable plot to re-engineer all of L.A. to function as an urban forest and sustainable watershed. Relying, like a growing number of L.A.'s environmental visionaries, on computer modeling, it's at once tenaciously practical, surprisingly doable and insanely ambitious. A cost-benefit analysis combines modest retrofits on existing houses, schools, businesses, parking lots — a cistern here, a grass schoolyard there, a redirected gutter, a porous sidewalk — to create a larger water-management plan that is sustainable, saves energy, costs far less and creates jobs.
Headworks Spreading Grounds. A recharge project that diverts river water, lets it percolate down toward the aquifer and self-clean, then pumps it back up. The city discontinued its use in 1983 when Tillman began to discharge wastewater too dirty to self-clean into the river, but the plant now treats to a higher standard. The Department of Water and Power wants to reactivate this 30-plus-acre site, complete with a final-stage treatment plant. Plus it will add trails, a bike path and an outdoor educational center. And the wet-dry cycles create wetlands. And the recycled water is roughly half the price of imported Metropolitan Water District water. A departure for DWP, which tends to fence its properties off. (ETA if approved 2003)
Taylor Yard. The huge future park is an ideal place to control floods before they reach downtown. The omnipresent Coastal Conservancy is studying the feasibility of a detention basin and wetlands or uplands restoration — and even of pushing back the levee to allow the river to move within a wider channel. Which options are doable will depend in part on the cleanup schedule for the soils and aquifer here.
The Cornfield. In the Chinatown Yard Alliance's park proposal (see Downtown), the grand meadow doubles as a detention basin for a major, 25-year flood.
Arroyo Seco — another microcosm of the future. If you want to see the first chunk of concrete fly, then camp out here, because of all the waterways in the basin, the Arroyo is on the fastest track to full-scale watershed management. Why the Arroyo? It has significant green space and less dense development along its banks — in other words, the prerequisites for sound water management that will take a long time to put into place on the L.A. River. A comprehensive study will begin by identifying the best sites for wetlands, stream naturalization, diversion basins, etc., and for a series of demonstration projects. It's brought to you by North East Trees with the Arroyo Seco Foundation, with funds from SMMC and the California Coastal Conservancy, a major funder of watershed projects on the river. (ETA study 2001)
High hopes abound that a new and improved Arroyo will become a model for the river. On an even larger scale, the new “Re-envisioning the Arroyo Seco Corridor” project — brainchild of the new Occidental College°©led Arroyo Seco Collaborative — will use studies and public programs to explore the Arroyo area as a showcase for improving livability and ecological sustainability in L.A.
Lower Arroyo Stream Restoration. Can concrete be removed safely or not? This 0.8-mile project has it both ways — and models an alternative strategy to reconnect the river to its basin until full-scale watershed management can make the world of L.A. safe for concrete removal. It diverts Arroyo water into constructed streambeds on both sides (Browning-Ferris Industries built it in 1997 as mitigation for a landfill in the Valley). It leaves the concrete channel intact, but it's converted a barren, disturbed patch of weeds into a healthy wetland.
Wrigley Heights park. The proposals (see The South) include wetlands restoration.
DeForest Park. Long Beach is conducting a study with Coastal Conservancy funds to see (1) if it can restore a linear strip of wetlands from the park's south end all the way to Del Amo Boulevard, and (2) if the wetland will clean the urban runoff enough for use in irrigation. Ideally, the city wants to see a nature center too. (ETA if feasible 2006)
Dominguez Gap. Public Works is looking into whether it can re-engineer these two existing basins (45 to 50 acres) to enhance recharge but also restore wetlands. With education programs and viewing areas. (ETA if feasible 2004)
Golden Shore Marine Biological Reserve. A restored tidal wetland (see The South).
Sixth Street. Long Beach will restore four acres of wetlands, with paths from nearby Cesar Chavez Park and elementary schools. (ETA start 2002)
Wetlands restoration in Long Beach. These projects, if and when they're green-lighted, would create a string of restored wetlands along seven miles on the east side of the river. Ideally, the city wants to make this strip continuous.
LACDA (Los Angeles County Drainage Area) Walls. The flood-control project that sped up watershed management — and that many hope will be the basin's last such single-purpose project. The original LACDA flood-control system, built in the 1930s to the 1960s ostensibly to hold a 100-year flood, didn't begin to imagine the massive future city of pavement. A 1992 Army Corps plan to raise the flood walls an average of 4 feet along the river's last 12 miles incited a wave of protests — and a 1995 lawsuit brought by Friends of the L.A. River, TreePeople and Heal the Bay. Detractors argued that we can't just keep building a bigger concrete box, but have to begin instead to capture and recycle storm water. The lawsuit failed. But the battle raised public awareness. It pushed restoration advocates to get specific, engineer style, about alternative strategies. It generated a dialogue among all involved, and helped produce a roughly shared vision of watershed management. (ETA finish 2001)