Flood Control Zone 1 was formed in 1954 to provide funding for construction and maintenance of regional drainage infrastructure in the Marsh Creek watershed. It initially provided, from a portion of the ad valorem property tax, local matching funding for a variety of joint District / Federal projects that resulted in construction of much of the regional drainage infrastructure in the watershed.
The District, in cooperation with its Federal partner, the US Department of Agriculture Soil Conservation Service (SCS, now called the Natural Resources Conservation Service, NRCS), constructed projects in the 1950s and 1960s that resulted in channelization of Marsh Creek from the mouth to the confluence with Dry Creek, channelization of portions of Sand, Deer and Dry Creeks and the construction of flood retarding reservoirs on Marsh Creek, Deer Creek and Dry Creek. These major regional drainage facilities provided a 50-year level of protection for the watershed’s predominantly agricultural land use.
In the mid-1970s, this system was expanded with the construction of earthen channels called Lines E and E1 in the area between Brentwood, Oakley and Antioch.
Subsequent to the construction of the original regional facilities, the communities of Brentwood, Oakley and Antioch experienced tremendous urbanization, which continues to this day. With the conversion of agricultural lands to urban uses, the communities desired an improvement from a 50-year to a 100-year level of flood protection.
In 1994, the District amended the FCZ 1 plan to include a number of regional detention basins, the expansion of previously constructed reservoirs and widening of selected reaches of the Marsh Creek channel. The plan amendment also adjusted the legal boundary of the zone to better match the Marsh Creek watershed boundary.
In 2006, the FCZ 1 plan was modified a second time to change three smaller detention basins from regional to subregional facilities, and to transfer responsibility for these three basins to the City of Oakley.
In December 2007, the District published the Flood Control Zone 1 Financial Plan.