City of Boulder/USGS Water Quality Monitoring
Water Quality Index for August, 2002 at
Middle Boulder Creek Above North Boulder Creek Confluence

Grade B For August, 2002 the WQI rating at Middle Boulder Creek Above North Boulder Creek Confluence (BC-aNBC) was Good (B) due to a WQI value of 84.18. 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 81.20 85.37 0.17 14.51
Fecal Coliform #/100 mL 20.00 61.54 0.16 9.85
pH pH 7.64 93.28 0.11 10.26
Total Phosphate mg PO4/L 0.07 95.32 0.10 9.53
Nitrates mg NO3/L 0.10 97.90 0.10 9.79
Turbidity NTU Data Unavailable
Total Solids mg/l 93.00 83.23 0.07 5.83
Totals (factors, total) 0.71 59.77
Adjusted WQI 84.18

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 July at this station

WQI for September at this station

Return to WQI map for August


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 - Saturday December 24, 2005