University of California Water Resources Center

WRC project W-727 focuses on evaluating the capacity of selected aquatic plant species for low concentrations of herbicide and nitrate removal from nursery waste waters. Two nurseries in the Sacramento area were selected as test sites. From June 1988 through October 1989, water samples from inflow and outflow water from both nurseries were collected and analysed for inorganic constituents and herbicides. Of the herbicides analyzed (simazine, oryzalin, oxyfluorfen and pendimethalin), only oryzalin and oxyfluorten were present in measurable quantities. Pendimethalin was never detected and simazine appeared in detectable quantities only twice. Both nitrate and ammonia nitrogen concentrations were consistently high in outflow from both nurseries, except for the period of about three months during the winter. Soluble reactive phosphorus was relatively low.