Background of Water Quality Monitoring
In February 2009, the Regional Board approved the Coalition’s first comprehensive Management Plan, which details the Regional Plan of Action to address multiple exceedances of water quality parameters at a given site within a three-year period. Within the Coalition’s ten subwatersheds, site specific management plans for registered pesticides and toxicity receive the highest priority for implementation with legacy pesticides and trace metals a medium priority and salinity (including conductivity and TDS), dissolved oxygen, pathogens, and pH a low priority, since these parameters have the highest number of potential non-agricultural sources and causes.
Butte-Yuba-Sutter Monitoring Sites
Gilsizer Slough at George Washington Road (GILSL)
Gilsizer Slough is an unlined, storm drainage outfall canal that runs from the Gilsizer County Drainage District’s north pump station approximately 15 miles to the Sutter Bypass, draining 6,005 total acres. The monitoring location is located roughly 1.5 miles from its confluence with the Sutter Bypass and is a natural drainage channel that historically drained Yuba City and the
area south of town. Principal crops grown in this area include prunes, walnuts, peaches, and almonds. This special project site currently is a Management Plan site for this subwatershed.
Lower Honcut Creek at Highway 70 (LHNCT)
Lower Honcut Creek (in the Lower Honcut Creek drainage) was selected to represent the drainages in the eastern part of the Butte-Yuba-Sutter Subwatershed. This drainage includes the dominant crops grown in the area and typically has flows allowing sampling through irrigation season. The sampling site is located approximately 3.5 miles from its confluence with the Feather River. Dominant crops in this drainage include rice, walnuts, prunes, pasture, citrus, olive, and grapes. Lower Honcut Creek receives flows from North Honcut Creek and South Honcut Creek, which extend up into the foothills and include more pasture acreage. This is a representative site for this subwatershed.
Lower Snake River at Nuestro Road (LSNKR)
The Lower Snake River is an unlined irrigation supply and runoff canal that serves approximately 25,000 total acres and includes a relatively high percentage of rice acreage. The other predominant crops include prunes, peaches, idle acreage, and operations producing flowers, nursery stock, and Christmas trees. This is a representative site for this subwatershed.
Pine Creek at Highway 32 (PNCHY)
The watershed sampled upstream from the Pine Creek monitoring site represents approximately 28,000 acres of varied farmland, riparian habitat, and farmsteads. The predominant crops in this area are walnuts, almonds, prunes, wheat, oats, barley, beans, squash, cucumbers, alfalfa, pasture, and safflower. This is a representative site for this subwatershed.
Sacramento Slough Bridge near Karnak (SSKNK)
This site aggregates water from all areas in the subwatershed between the Feather and Sacramento Rivers. The major contributing areas include the areas downstream of the Butte Slough and Wadsworth monitoring sites. These areas include Sutter Bypass and its major inputs from Gilsizer Slough, Reclamation District (RD) 1660, RD 1500, and the Lower Snake River.
This is an integration site for this subwatershed.