The purpose of this study was to quantify the effects of land use on water quality in Ladner Slough, and in the major drainages feeding Ladner Slough. Water samples were collected monthly during the winter of 1976 up until the month of April, 1977. Samples were also collected in August 1976 and August 1977. Soil and sediment samples were collected twice throughout the sampling period in order to aid in determining the net effect of various land uses on water quality. Sampling sites were located on Ladner Slough, Cohilukthan Slough, Crescent Slough, and Deas Slough. In that context, they were located within various different land use areas, and within transition zones between land use areas. Concentrations of metals, nutrients, and major cations in water samples were determined. Analogous determinations were made on the soil and sediment samples taken. The results of numerous statistical analyses suggested that iron and total nitrogen were the water quality parameters that are most sensitive to land use in the Ladner area. Some water quality parameter magnitudes in every slough were found to exceed guideline objectives for domestic use in one or more months throughout the study period. Sloughs draining or adjoining urban zones were observed to exhibit generally the highest concentrations of metals. A site near the sanitary landfill area, on the periphery of Burns Bog, also exhibited consistently high metal concentrations. High nutrient concentrations were most often found in conjunction with agricultural land, and probably resulted from point sources. The highest concentrations of major cations were found in the slough which was closest to the Strait of Georgia. Soil and sediment data did not correlate closely with water quality data. Relatively high concentrations of lead were found in the sediment from Ladner Slough. This was thought to result from the heavy marine traffic on that slough, and could represent a potential sink for that metal. The water quality in Ladner Slough did not differ significantly from the water quality of Deas Slough. This implies that the Fraser River may flush both of the above sloughs periodically. The effects of land use on water quality in the Ladner area are discernable, and often pronounced. Moreover, some water quality problems were found to exist. This report recommends that a surface water and groundwater monitoring network be established in the area in order to provide a greater data base, and to better define specific deleterious activities. Emphasis should be placed on nutrients draining from agricultural land, and metals draining from both urban land, and the sanitary landfill area on the periphery of Burns Bog. / Land and Food Systems, Faculty of / Graduate