BASIN: Water Quality Index for May, 2006 at Boulder Creek at 107th St


	City of Boulder/USGS Water Quality Monitoring
	Water Quality Index for May, 2006 at Boulder Creek at 107th St

Grade C For May, 2006 the WQI rating at Boulder Creek at 107th St (BC-107) was Medium (C) due to a WQI value of 69.69. The chart below details the WQI calulations at this site. See the detailed explanation of the WQI method for more information.

Parameter	Unit	Parameter Value	Q-value	Weight Factor	Total
DO%	% sat	117.10	92.67	0.17	15.75
Fecal Coliform	#/100 mL	80.00	44.37	0.16	7.10
pH	pH	8.01	86.56	0.11	9.52
Total Phosphate	mg PO4/L	0.60	52.26	0.10	5.23
Nitrates	mg NO3/L	Data Unavailable
Turbidity	NTU	10.60	72.62	0.08	5.81
Total Solids	mg/l	230.00	66.77	0.07	4.67
Totals (factors, total)				0.69	48.08
Adjusted WQI					69.69

The WQI is computed by converting measured Water Quality Parameters to "Q-Values" using charts developed by the National Sanitation Foundation (NSF) water quality scientists. The Q-Values are then multiplied by a weighting factor based on the importance of that water quality parameter. These values are totaled and then divided by the sum of the weight factors.

WQI at Upstream Station: Boulder Creek at 95th St

WQI at Downstream Station: Boulder Creek Above Coal Creek

WQI for April at this station

WQI for June at this station

Return to WQI map for May

Thank You! BASIN was a community project which benefitted from over 1000 hours of public volunteer time. BASIN was highlighted by the US EPA in a national case study in its 2001 handbook Delivering Timely Environmental Information to Your Community. Thank you to all volunteers, and especially to the late Jim Waterman, BASIN Project Coordinator!