Colorado’s latest posted public-health notices continue to warn against direct water contact at Lake Meredith and parts of the Arkansas River after a 4.2 million-gallon sewage spill in Pueblo, even as John Martin Reservoir has reopened for recreation.
The most recent Lake Meredith notice, published Sept. 14, says water affected by the spill reached the lake in Ordway and advises residents to avoid swimming, wading, fishing and other activities involving contact with the water. It also tells owners to keep pets and livestock from drinking or entering the lake. The public notice says it will be updated when additional testing or information is available.
The warning is the latest consequence of an Aug. 26-27 failure at Pueblo’s wastewater system. The spill released untreated sewage into the Arkansas River and took about 24 hours to detect and stop, according to reporting that reviewed the state’s sampling results and local response. The incident has affected recreation across multiple southeastern Colorado communities, making the status of individual stretches of river, reservoirs and ponds important for residents planning to fish, boat or enter the water.
Advisories differ by location
Colorado’s dedicated Arkansas River spill page is the central state source for incident updates, sampling data and advisory changes. The Colorado Department of Public Health and Environment says advisories will be lifted when water quality returns to the applicable standard, so a cleared site should not be treated as evidence that every downstream location is safe.
That distinction is already visible. CDPHE lifted the John Martin Reservoir recreation advisory after samples showed bacteria levels below the public-health threshold. Prowers County likewise reported that the reservoir was cleared for all recreational activities.
But a Sept. 1 sample near U.S. 50 in Lamar measured E. coli at 613.1 colony-forming units per 100 milliliters, compared with a public-safety threshold of 235. Prowers County’s published health-department update advised people to avoid swimming, wading, tubing, fishing and boating there until further notice. It said officials would keep sampling affected routes and announce when that advisory could safely be lifted.
What residents should do
People considering river or lake recreation should check the state’s sampling dashboard and the latest county or municipal notice for the exact location they plan to visit. Conditions and advisories are site-specific: John Martin Reservoir’s reopening does not override the Lake Meredith notice or any separate warning for the Arkansas River near Lamar.
Until officials publish a location-specific clearance, the practical course is to stay out of posted waters, keep children and animals away from them, and avoid activities that can produce accidental ingestion or prolonged skin contact. Residents who need the newest local guidance can use the contact information on CDPHE’s incident page or consult their county public-health agency before entering the water.
