North Creek Water Quality Prepared by Jon Rogers and Carie McCoy

Dr. Jaffe’s Environmental Chemistry Lab Class January 21 st – February 3 rd, 2005

North Creek Adjacent to the UWB/CCC Campus in the Sammamish Valley of King County, WA Approximate latitude and longitude: 47 o 45’ 21” N 122 o 11’ 20”W Upstream Site: East of exit number 24 off I-405 Downstream Site: Past the Boardwalk in the UWB/CCC Wetlands

Goals Determine if the wetland helps contribute to improved water quality. To determine if North Creek complies with state standards.

Study Parameters pH: effects chemical and biological processes which occur in an aquatic environment Conductivity: measures ionic potential of the waterway Temperature: influences rates of chemical and biological processes Dissolved Oxygen (DO): concentration of oxygen which is in a dissolved form in the water Stream Flow: volume of water moving over a designated point at a fixed period of time Turbidity: measured amount of suspended sediments in the water Nitrates: measure of nitrogen as nitrate (N0 3 -N) in the water Phosphates: measure of phosphorous as phosphate (PO 4 -P) in the water

Effects of Parameters pH: if pH is too acidic or alkaline than the water becomes inhabitable by aquatic life (desired pH range ) Conductivity: effects the buffering capacity of the water Temperature: influences amount of DO (optimal <20 o ) DO: form of oxygen available for aquatic life Stream Flow: help determine amount of impervious surface area in the watershed Turbidity: increased turbidity may cause damage to fish gills, suffocating them Nitrates: can determine amount of fertilizer runoff entering the stream (septic runoff is also a source) Phosphates: corallites with the amount of soaps and detergents in the water

Profiling a stream Measure the width of the stream channel At equal intervals of width (0.5 m) measure stream death Post a reference point for future depth measurements

Significant Results Flow –Statistically significant difference (P=.01) in flow from the two sites –Greater stream flow at the upstream site than downstream –Possible reason is the water absorbing quality of the wetland –Rain event prior to data collection and approximately 0.03 cm of precipitation during our survey

Statistical Runner Up Conductivity –Using a paired T-test we verified a P value of P=0.065 –Almost a significant difference. Desire P<0.05 –What if the study had a longer duration? –Is there an outlier?

Conclusions We found the wetland does help absorb runoff during rain events At the time of our study, the area of North Creek we evaluated does comply with Washington State Department of Ecology Standards for a class A stream Stream quality may change during other seasons

Questions?