Streams in the Baldwin Hills Oil Fields
August 18, 2008 § Leave a comment
The County of LA is working with partners to renew oil leases at the Baldwin Hills oil fields. (EIR here)
The Baldwin Hills are perhaps best known for the sight of the oil derricks, but also the Kenneth Hahn State Park, and the more recent Baldwin Hills Conservancy. What is hard to believe, is that even on those dry slopes, there are seeps and, formerly, streams.
The 1902 USGS shows several intermittent streams, and also shows the topopgraphy (no blueline) associated with ephemeral streams. Intermittent streams run through part of the year, and often have willows, mulefat, and some wetlands plants sustained throughout the year, due to moisture in soil. Ephemeral streams tend to carry stormwater to intermittent streams, and have drier, more disturbance-oriented plants in their channels and floodplains. Both are home to uniquely adapted species of wildlife, that like the seasonal conditions.
At right is a view from a 1924 USGS map, with today’s streets overlaid. This is the area of oil field between La Cienega and La Brea, Stocker Avenue and Slauson. Two significant streams can be seen here, with some smaller ephemeral tributaries draining into them. These two big creeks then flowed into Centinela Creek, a concrete pipe and channel today.
Compare this image with a Google Earth aerial at right, and you see traces of the streams in little undeveloped valleys. But there have been changes: there are basins in the stream bed, some of the stream has been culverted (piped), and otherwise filled or altered. They’re called “ditches” now. The extensive disturbance of the soil on these hills (see all the bare dirt – the light sand color on the aerial) is likely to wash into the streams, choking amphibians and other species that may be laying eggs (or used to) in the streams’ bed.
Of course, field verification would be needed to really understand how the streams have changed, and what the impact to wildlife has been. Now, there was probably nothing illegal about impacting these streams – it was mostly likely done before the Clean Water Act (unless there were Fish & Game protections in place before CWA – I really don’t know). And with proper permitting and mitigation, there’s also no restriction on disturbing the streams (all you need to do is the paperwork). However, this is a great moment to seek restoration and minimally invasive land management methods. These streams are a public resource, and in the long term could be part of the Baldwin Hills State Park, as was envisioned in the Baldwin Hills Park Master Plan.