BASIN: Water Quality Index for April, 2006 at Boulder Creek above Dry Creek


	City of Boulder/USGS Water Quality Monitoring
	Water Quality Index for April, 2006 at Boulder Creek above Dry Creek

Grade C For April, 2006 the WQI rating at Boulder Creek above Dry Creek (BC-aDC) was Medium (C) due to a WQI value of 55.04. 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	160.00	50.00	0.17	8.50
Fecal Coliform	#/100 mL	50.00	49.77	0.16	7.96
pH	pH	7.29	92.62	0.11	10.19
Total Phosphate	mg PO4/L	2.62	20.65	0.10	2.06
Nitrates	mg NO3/L	Data Unavailable
Turbidity	NTU	11.30	71.15	0.08	5.69
Total Solids	mg/l	352.00	50.97	0.07	3.57
Totals (factors, total)				0.69	37.98
Adjusted WQI					55.04

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 above WW Plant

WQI at Downstream Station: Boulder Creek at 95th St

WQI for March at this station

WQI for May at this station

Return to WQI map for April

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!