City of Boulder/USGS Water Quality Monitoring
Water Quality Index for April, 2006 at
Middle Boulder Creek Above North Boulder Creek Confluence

Grade A For April, 2006 the WQI rating at Middle Boulder Creek Above North Boulder Creek Confluence (BC-aNBC) was Excellent (A) due to a WQI value of 91.89. 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 90.10 93.81 0.17 15.95
Fecal Coliform #/100 mL Data Unavailable
pH pH 7.89 89.67 0.11 9.86
Total Phosphate mg PO4/L 0.02 98.23 0.10 9.82
Nitrates mg NO3/L Data Unavailable
Turbidity NTU 3.50 88.69 0.08 7.10
Total Solids mg/l 32.00 85.32 0.07 5.97
Totals (factors, total) 0.53 48.70
Adjusted WQI 91.89

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: Middle Boulder Creek at PSCo Weir

WQI at Downstream Station: North Boulder Creek diversion to Lakewood

WQI for March at this station

WQI for May at this station

Return to WQI map for April


INVITATION: BASIN is a community project actively seeking public participation. We appreciate all feedback and welcome comments, suggestions and contributions. To find out more about how you can be involved, click here.

Home | Site Map | Glossary | Bibliography | Contributors
About BASIN | Attribution | Feedback | Search
Last Page Update - Thursday March 01, 2007