Ballona’s historical ecology – and new awesome map site
January 23, 2012 § 7 Comments
As many of you probably already heard, last week the Coastal Conservancy approved up to $6.5 million to complete studies and permitting for the Ballona Wetlands. If that price tag for planning is giving you sticker shock, I have two words: Army Corps. Actually more than two words – you see, one alternative proposes removing and relocating the levees that currently contain Ballona Creek’s flows from spreading over the wetlands. (You know, the way in undisturbed situations fresh water from a stream or river normally spreads over wetlands, making the land, you know, wet.) And removing and relocating levees is sensitive business, and an involved regulatory process that has to be paid for and that can rapidly add up to a big chunk of the $6.5m.
That’s just the regulatory/cost barrier. Some people are concerned about the potential flood risk to humans, while others are concerned about the flood risk to…the wetlands. This has been an ongoing debate, and while it’s not the point of today’s post, I think we’ve got new information that can help us all consider the alternatives – as well as create new projects. Back when I was watershed coordinator, I felt the conversation about the watersheds could be elevated if we had a better handle on the historical ecology of the watershed. Agreed-upon, documented sense of what natural processes shaped the habitats of the watershed, and what had actually been here. I drafted a proposal for this study, as well as an assessment of the watershed’s springs/water budget, both of which got funded and managed by others later.
And the historical ecology report is done, and is beautiful! Props to the team comprised of CSUN, SCCWRP, SFEI and UCLA researchers! This report provides insight into the diverse habitats of the Ballona Creek watershed, and demonstrates considerable evidence that lower Ballona Creek was much like a large marsh, with a considerable prism of marsh and wetland habitats from the base of the Baldwin Hills down to the ocean. While Ballona Wetlands restoration won’t reestablish historical conditions – and any work to restore Ballona Creek or its tributaries will face significant physical constraints, the study does provide information that can help us make the best use of the land and the natural processes (hydrologic flows) that remain in the interests of reestablishing wetland and riparian habitats. The accompanying website (photo above) they created also fulfills one of my long-standing wishes (although I’d love to have this for all LA’s watersheds) – an overlay map of streams and wetlands against today’s landscape, so you can find the lost creek near you! Check it out, enjoy!
P.S. You’ll find many other great studies posted under Technical Reports at SCCWRP’s website. Among them, the springs/Ballona hydrology assessment, a historical ecology study of the lower Santa Clara River & Oxnard Plain, a report on episodic channels, studies on hydromodification (channelization etc), and tendencies of southern California wetlands to seasonally open and close and on and on. Good stuff for folks who want to better understand our waterways and watersheds.