1. City of Greeley Prepared for the Water Quality Control Commission
IN THE MATTER OF THE ADOPTION OF REVISIONS TO THE CACHE LA POUDRE SEGMENT 12 IN THE CLASSIFICATIONS AND NUMERIC STANDARDS FOR THE SOUTH PLATTE RIVER BASIN, LARAMIE RIVER BASIN, REPUBLICAN RIVER BASIN, SMOKY HILL RIVER BASIN, REGULATION #38 (5ccr )
Prepared for the Water Quality Control Commission
June 2015

2. Summary of Temperature Issues
Greeley proposes a temporary modification to the temperature standards on Segment 12 of the Cache la Poudre River with the following terms:
Daily maximum temperature (DM) = current condition
Weekly average temperature (WAT) = current condition
Compliance issues
Demonstrated/predicted compliance issue, as evidenced by five years of effluent, upstream and downstream temperature data
Significant uncertainty regarding the extent to which existing quality is the result of natural or irreversible human-induced conditions, as demonstrated by upstream summer temperatures
City of Greeley

3. Temperature Data Collection and Assessment
City of Greeley

4. Compliance Issue
City of Greeley

5. Plan to Resolve Uncertainty
Temperature Data Collection and Assessment
Collect additional temperature data for Segment 12 at additional locations upstream of discharge point
Investigate cause of upstream temperature exceedances to determine if an ambient based site-specific standard is appropriate
Aquatic Life Data
Acquire fish and macroinvertebrate data in Segment 12 to determine if recalculation is appropriate
Evaluate for evidence of a balanced, indigenous aquatic life population
Feasibility Studies
Evaluate the technological, economic, and environmental feasibility of alternate temperature management strategies.
Regulatory Involvement
Continue to participate in the Basic Standards Workgroup and the Permit Issues Forum’s discussions of temperature standards
City of Greeley

6. Summary
A temperature temporary modification is appropriate based on demonstrated/predicted temperature issues
An expiration date of 12/31/2020 is appropriate to allow time to resolve uncertainty in Segment 12, both upstream (Fort Collins) and downstream (Greeley).
Due to winter issues upstream and summer issues downstream, a year-round temporary modification of current condition for temperature in Segment 12 is appropriate.
City of Greeley