Proceedings of the 2007 Georgia Basin Puget Sound Research Conference
Session 1D: Fresh Water Quality
Chair: Zita Botelho
Island County's Surface Water Monitoring Program
Island County, Washington, has begun a 5-year program of monitoring water quality in streams, lakes, and wetlands of Whidbey and Camano Islands. Local funds are being used partly to measure effectiveness of the County’s critical areas protection ordinance and to identify and reduce pollution potentially exported to Puget Sound. During the first year, non-tidal surface waters in 45 of the County’s 126 small rural watersheds are being monitored for nutrients, temperature, dissolved oxygen, coliform bacteria, turbidity, conductivity, hardness, pH, and (wetlands only) vegetation composition. Many streams flow only seasonally. Initially, most watersheds are being sampled at just one location, generally just above the marine interface. Monitoring in 24 watersheds will be conducted twice monthly each year. Eight of these watersheds are largely agricultural (mostly pasture), eight have significant residential development, and eight are relatively natural. Other watersheds will be sampled for shorter periods until nearly all of the County’s watersheds have been assessed and major sources of pollution are traced and remedied. Watersheds were prioritized systematically for monitoring based on scores for valued resources and pollution risk. Results will be reported regularly beginning next year. Response actions, including intensified monitoring, will be based on measured trends and chronic exceedences of standards.
Exploring Seasonal Dynamics of Some Antibiotic Resistance Genes and Antibiotics in an Agricultural Watershed
Located in the heart of Georgia Basin is the trans-boundary Sumas watershed. Recognized as one of the most productive agricultural regions in British Columbia and Washington State, the watershed has seen an increase in intensification of agricultural activities, especially production of food animals, over recent decades. Increase in livestock and poultry production is coupled with increased need for veterinary use of antibiotics. Concern that antibiotic use in agriculture could impact ecosystem and human health through the development of antimicrobial resistant strains of pathogens led to this study conducted in the Sumas watershed between July 2004 and March 2006. During this period, four tetracycline resistance genes and fourteen antibiotics used in veterinary medicine were monitored monthly in the Sumas River receiving environment. Microbiological methods of real-time PCR were used to measure tetracycline resistance genes and high performance liquid chromatography tandem mass spectrometry analyses determined antibiotic residues in samples from various ecosystem compartments. This paper will discuss the results of the monitoring effort that suggests the observations are a function of agricultural point source contributions, receiving water quality and hydrographic conditions in the region. Seasonal patterns of the observations appear consistent from year to year.
Status of Nitrogen, Phosphorus and Potassium in Lower Fraser Valley Agricultural Soils in Relation to Environmental and Agronomic Concerns
Soils within the Fraser Valley of British Columbia are among the most fertile in Canada supporting a diverse range of agricultural production. As livestock density has increased, census based nutrient balance models have pointed towards nutrient surpluses within the region but there has been a lack of scientific data to quantify soil nutrient concentrations. A study was undertaken in 2005 to determine soil nitrogen, phosphorus and potassium status in the Fraser Valley for establishing baselines and monitoring the effectiveness of government activities, including the Canada-British Columbia Environmental Farm Plan Program.
Soil testing and analysis methods were already available for agronomic purposes, but methods for environmental interpretations were limiting. Residual (after-harvest) soil nitrate has been used for environmental (and agronomic) assessment but nothing was available for environmental assessment of soil phosphorus and potassium. The study included two types of sampling; 1. those to develop analytical methods and interpretations for phosphorus and potassium (Phase A) and to examine the influence of sampling time on residual soil nitrate (Benchmark), and 2. those to use the developed methods to examine the relative environmental status of nutrients in soils of six geographic zones that had previously been calculated to have contrasting nutrient balances (Phase B). All samplings were replicated to distinguish field differences from random variability.