Water Quality Updates & Data

The Authority, in coordination with the Chatfield Reallocation Water Providers, conducts water quality monitoring in the Chatfield Reservoir Watershed at six locations:

  1. Chatfield Reservoir – Reservoir Centroid
  2. Chatfield Reservoir — South Platte Arm
  3. Chatfield Reservoir — Plum Creek Arm
  4. Plum Creek at Titan Road
  5. South Platte at Waterton Road
  6. Outflow from Chatfield Reservoir

Water quality compliance at Chatfield Reservoir is based on meeting July-September average concentration of total phosphorus (water quality standard of 30 ug/L) and chlorophyll-a (water quality standard of 10 ug/L). The analyte list is focused on compliance metrics for total phosphorus and chlorophyll- a, in addition to other nutrients (ortho-phosphorus, ammonia, nitrate, and nitrite) and other constituents of concern that demonstrate a healthy reservoir such as dissolved oxygen, total suspended solids, temperature, and specific conductance. All data collected by the Authority is summarized in Annual Master Data Spreadsheets, provided below.

CRMC-CWA Monitoring Amended MOU & SAP

Chatfield Watershed Compliance Metrics and Total Phosphorus Loads (1983-2010) (excel)
2017 Water Quality Report (excel)
2016 Water Quality Report (excel)
2014 Master Data Spreadsheet (excel)
2013 Master Data Spreadsheet (excel)
2012 Master Data Spreadsheet (excel)
2011 Master Data Spreadsheet (excel)
2010 Master Data Spreadsheet (excel)
2009 Master Data Spreadsheet (excel)
2008 Master Data Spreadsheet (excel)
2007 Master Data Spreadsheet (excel)
2006 Master Data Spreadsheet (excel)
2005 Master Data Spreadsheet (excel)
2004 Master Data Spreadsheet (excel)
2003 Master Data Spreadsheet (excel)
2002 Master Data Spreadsheet (excel)
2001 Master Data Spreadsheet (excel)
2000 Master Data Spreadsheet (excel)
1999 Master Data Spreadsheet (excel)
1998 Master Data Spreadsheet (excel)
1997 Master Data Spreadsheet (excel)


Water quality data from the Swim Beach of Chatfield Reservoir at Chatfield State Park is collected by Colorado State Parks Rangers. The numbers are measured as the number of E. coli organisms per 100 milliliter (ml) sample. The maximum contaminant level allowed by the Colorado Department of Public Health and Environment is 235 organisms of E. coli per 100 ml sample. Sources of E. coli include birds and people. For more information about water quality at the Chatfield swim beach, please contact Park Rangers at 303-791-7275, ext. 114.

Swim Beach Water Quality 2014
Swim Beach Water Quality 2013
Swim Beach Water Quality 2012
Swim Beach Water Quality 2011
Swim Beach Water Quality 2009 (excel)
Swim Beach Water Quality 2009
Swim Beach Water Quality 2007
Swim Beach Water Quality 2006


As a recipient of the Healthy Rivers Fund Grant in 2012, the Authority also collected monthly water quality data in the Plum Creek Watershed at ten locations in East Plum Creek, West Plum Creek and the Plum Creek mainstem to better understand potential sources of nonpoint source pollutants in the watershed. Starting in May 2013, Authority member Plum Creek Water Reclamation Authority (PCWRA) has led the monthly sampling and analysis effort. The Plum Creek Watershed Monitoring Network Sampling and Analysis Plan and Plum Creek watershed data are provided below.

Plum Creek Sampling and Analysis Plan
Plum Creek Watershed Data (excel)


Historical Water Quality Reports
The Chatfield Watershed Authority’s historical archive of water quality reports includes the following documents:

Chatfield Water Quality Report 2003
Chatfield Water Quality Report 2002
Chatfield Water Quality Assessment 1990-2001
Chatfield Water Quality Report 2001
Chatfield Water Quality Report 2000
Plum Creek WW Authority – WQ Assessment 2000
Chatfield Water Quality Report 1999
Chatfield Water Quality Report 1998
Chatfield Water Quality Report 1997
Chatfield Water Quality Report 1996
Chatfield Water Quality Report 1995
Chatfield Water Quality Report 1994
Chatfield Water Quality Report 1993
Chatfield Water Quality Report 1992
Chatfield Water Quality Report 1991
Chatfield Water Quality Report 1990
Chatfield Water Quality Report 1989
DRCOG Chatfield Basin Water Quality Study 1988