BASIN: Water Quality Index for May, 2006 at North Boulder Creek at Boulder Falls


	City of Boulder/USGS Water Quality Monitoring
	Water Quality Index for May, 2006 at North Boulder Creek at Boulder Falls

Grade A For May, 2006 the WQI rating at North Boulder Creek at Boulder Falls (NBC-FALLS) was Excellent (A) due to a WQI value of 91.12. 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	106.20	98.35	0.17	16.72
Fecal Coliform	#/100 mL	Data Unavailable
pH	pH	6.89	83.61	0.11	9.20
Total Phosphate	mg PO4/L	0.05	97.26	0.10	9.73
Nitrates	mg NO3/L	Data Unavailable
Turbidity	NTU	4.74	85.57	0.08	6.85
Total Solids	mg/l	96.00	82.90	0.07	5.80
Totals (factors, total)				0.53	48.29
Adjusted WQI					91.12

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: North Boulder Creek diversion to Lakewood

WQI at Downstream Station: Boulder Creek at Orodell

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!