The Denver Department of Environmental Health’s Division of Environmental Quality (DEQ) monitors the streams and lakes within the City and County boundaries. Streams are monitored year-round while lakes are typically sampled once per year during the summer. Results from this monitoring are summarized in annual reports which are now being made available online. If you would like a CD version of a report, or if the report and/or information that you are interested in is not listed below or is inaccessible, please contact the City and County of Denver by calling 3-1-1 and request the Division of Environmental Quality.