EHL participated in an advisory committee that charted a balanced path to flood control and ecosystem protection in Riverside County.



The San Jacinto River drains from the San Jacinto Mountains into Lake Elsinore. On the way, it periodically fills Mystic Lake wetlands and supports shorebirds. Near the City of Perris, the river has a broad floodplain with rare alkaline soils, which support a community of rare plants dependent upon periodic floods. Agriculture and housing development compete for space, with major freeways crossing the river. Various water supply facilities are also present.

The Western Riverside County Multiple Species Habitat Conservation Plan (MSHCP) sets standards for conservation of the floodplain but a detailed plan to resolve all the conflicting uses has been under development off and on for many years. In the meantime, though, the MSHCP has acquired land and has worked with a landowner to set up an important mitigation bank.

The Riverside County Flood Control District convened stakeholders – EHL included – in 2016 to formulate alternatives to evaluate further in an environmental impact report. The committee set the reasonable goal of protecting the key thoroughfare – I-215 – from flooding, and made the MSHCP a top priority. Input from state and federal wildlife agencies was obtained. Over a period of months, the capable consultant team sorted through layers of complexity and identified a range of options and a tentatively preferred alternative.  

EHL is comfortable with the alternatives and notes that what may emerge as the preferred option exceeds MSHCP requirements, provides space for infrastructure, and asks housing development at the fringe to pay its fair share for flood control. An innovative buried pipeline would convey urban run-off and allow the establishment of a natural riparian system further downstream.

EHL offers a special commendation to Supervisor Marion Ashley, a longtime leader of the MSHCP, whose guidance kept stakeholders on track.