What is Low Impact Development (LID)?
According to the California Coastal Commission, Low Impact Development is “gaining popularity as a better approach to stormwater management that seeks to control stormwater at the source, using small-scale integrated site design and management practices to mimic the site’s natural hydrology. LID techniques include using permeable pavements, rain gardens, rain barrels, grassy swales, soil amendments, and native plants. Preserving natural vegetation and natural drainage patterns are also important LID tools. LID techniques can help development meet water resource protection goals and requirements, while providing benefits to developers, property owners, and communities.”
In Green Infrastructure for Los Angeles, the City of Los Angeles explains that Low Impact Development (LID) is “an approach to stormwater management that emphasizes the use of smallscale, natural drainage features integrated throughout the city to slow, clean, infiltrate and capture urban runoff and precipitation, thus reducing water pollution, replenishing local aquifers and increasing water reuse.”
Surfrider describes Low Impact Development as “a site design that aims to maintain and restore the water cycle in developing watersheds. Sometimes coined “Green Infrastructure”, LID uses site-specific engineering designs that utilize Best Management Practices (BMPs) to infiltrate, filter, store and treat stormwater close to its source. LID techniques are most effective when they are incorporated into the design for new development, but both commercial and residential properties can be retrofitted to hold more rainwater on-site.”
Currently, our Sustainable City Action Plan (September 2009) recommends the City implement the following “actions” related to Low Impact Development:
· Encourage the use of development techniques to direct rooftop runoff to pervious areas such as yards, garden beds, vegetated/soft bottom open channels, or on-site structural BMPs for capture, treatment, and reuse.
· Design streets to direct rainwater runoff to landscaped areas.
· Utilize and/or replace non pervious surfaces with permeable materials (e.g. sidewalks, driveways, outdoor patios and parking lots).
· Update development standards to require low impact development strategies such as detention basins, infiltration trenches, conservation of natural areas, permeable pavements, treatment wetlands, bioswales, curb cuts, green roofs, rain gardens and other pre/post constructions BMPs.
What are the benefits of LID?
Low impact development improves flood control in our aging storm drain system, reduces pressure on the sewage treatment system, prevents river and ocean pollution, reduces the demand for water use in our yards, parks, medians and parkways, helps to replenish groundwater aquifers, promotes natural green space, increases the availability of green jobs, and saves money on the capital costs for stormwater management infrastructure.
The EPA maintains that “LID can be applied to new development, redevelopment, or as retrofits to existing development. LID has been adapted to a range of land uses from high density ultra-urban settings to low density development.”
Low impact development can be a significant arrow among many in Long Beach’s quiver, supporting our ongoing efforts to encourage upstream cities to better manage their non-point source pollution and litter, which ends up making its way to the Los Angeles River and eventually to our harbor and beaches.
Are there other cities or counties implementing LID policies or ordinances?
Yes. Several cities, counties and organizations have already adopted Low Impact Development policies to encourage and/or require these design methods. They include: Los Angeles, Los Angeles County, Santa Monica, Ventura County (and its 10 cities), San Diego County (and its 18 cities), San Francisco, Portland, Seattle and even the U.S. Navy.
In sum, LID principles and practices offer economical, site-specific solutions for onsite prevention (rather than mitigation) of urban runoff into our harbor, beaches, park lakes and rivers.
( Low Impact Development Motion )