John Martin Reservoir State Park

08/30/2026

Press Release
August 30th, 2026

HASTY, Colo. – Colorado Parks and Wildlife advises visitors to John Martin Reservoir State Park to avoid contact with the Arkansas River and John Martin Reservoir beginning Monday, Aug. 31, as water affected by a 4.2-million-gallon untreated sewage spill in Pueblo moves downstream.

The sewage entered the Arkansas River in Pueblo Aug. 26-27 and is expected to reach the reservoir by Monday morning.

CPW is coordinating with the Colorado Department of Public Health and Environment and CPW’s Water Resources staff. That coordination has kept park staff informed as the spill moves downstream and allowed the park to prepare a monitoring plan. CDPHE will collect water-quality samples at the park.

“I’m grateful for the communication that has kept us up to speed from the onset,” said Dan Kirmer, JMRSP Manager. “While we cannot fix what is coming downstream, we have an opportunity to prepare and communicate with our visitors before it arrives.”

The park remains open and the advisory applies to activities involving direct contact with water in the Arkansas River and John Martin Reservoir.

Beginning Monday, visitors should avoid swimming, wading, tubing, paddleboarding, fishing and other activities involving direct water contact. Visitors should also keep pets away from affected water.

Warning signs will be posted at the park and around the reservoir to alert visitors to the contamination and water contact advisory.

The sewage spill comes as park staff are monitoring separate water-quality concerns involving cyanobacteria, commonly called blue-green algae. The reservoir was recently downgraded to a yellow caution level for possible algae-producing cyanobacteria and toxins, and regular testing continues.

Lake Hasty, a separate body of water at the park, remains under a red danger algae condition and closed to full-body water contact after its most recent test showed levels had increased again.

“Lake Hasty will not be impacted by the sewage spill, but its existing algae restrictions remain in place,” Kirmer said. “We will continue testing and communicating with our visitors as conditions change.”

CDPHE will collect water-quality samples at the park, and CPW will update the advisory as sampling results become available.

Visitors should follow posted signs and check the John Martin Reservoir State Park webpage for current park conditions and updates.

08/28/2026

Park and water updates:

Reservoir storage: 20,567 acft
Water temperature: 86
Weather: slight breeze, still hot

Fishing on the reservoir has still been pretty slow. Still catfish and white bass,not much else. The algae in the water is producing toxins below dangerous levels, so visitors are allowed to swim in it, but proceed with caution. Lake Hasty algae is still producing toxins at dangerous levels. So it is still closed to swimming.

The east boat ramp remains open and will remain open for the rest of the season, but with lowering water levels, the dock has been moved off the ramp and into the cove right next to the ramp.

Work has begun on the demolition of the old bathroom building near caddoa. Crews are currently working on removing hazardous materials safely, the full demolition will follow.

For questions, please direct message us or call our office at 719-829-1801.

08/24/2026

Did you know?

If you have a library card with your local library, you already have access to all of Colorado's state parks! For years, Colorado Parks and Wildlife have partnered with the Colorado State Library to offer free park access anytime of year through the Library Loaner Program. All you have to do is borrow and return the pass from your local library.

Check out other specialty park pass programs at: https://cpw.state.co.us/park-specialty-passes

08/22/2026

Park and water updates:

Reservoir storage: 21,797 acft
Water temperature: 87
Weather: some storms, still hot

Reservoir water levels are starting to drop a little bit quicker. Once we hit approximately 19,000 acft, the ramp will become a single-lane, so make sure to back your trailer in carefully. The dock will still be available, it will just be moved off the ramp and onto the low-water cable next to the ramp.

Still plenty of white bass in the reservoir, and catfish are starting to come out during those cooler nights.

For questions, call our office at 719-829-1801 or direct message us.

08/12/2026

Park and water updates:

Reservoir storage: 22,549 acft
Water temperature: 88
Weather: still 🔥

Still plenty of small white bass/wipers in the lake, but not much else is coming out. School starting up and the heat means less crowded shorelines, but also less people reporting their catches.

The algel toxin concentrations are now above the 8ug/L threshold for safe recreation in BOTH Lake Hasty and John Martin Reservoir, so both bodies of water will be closed for swimming and body contact. If you do swim in the water, please rinse off immediately.

After Labor Day weekend, our slow season starts. Starting Tuesday September 8th, visitor center and ANS boat inspection hours will be available from 8am-4pm until October 31st.

For questions, please direct message us or call our office at 719-829-1801.

08/07/2026

Come join us for a conversation about white tail deer tomorrow at the park visitor center at 1:00PM!

08/05/2026

Press Release

Aug. 5, 2026

HASTY, Colo. – Colorado Parks and Wildlife advises visitors to avoid direct skin contact with the water in the west boat ramp cove at John Martin Reservoir State Park after routine water sampling detected blue-green algae toxin levels above the Colorado Department of Public Health and Environment's recommended threshold for recreational water contact.

Water samples collected from the west boat ramp cove measured 10 micrograms per liter (µg/L) of algal toxins, exceeding the recommended recreational threshold of 8 µg/L. As a precaution, CPW has replaced advisory signage at the affected public access points and is asking visitors and their pets to stay out of the water in the west boat ramp cove until follow-up testing indicates it is safe to resume normal water contact.
Recent testing found no detectable algal toxins at the east boat ramp. Water samples collected from nearby Lake Hasty measured 2.5 µg/L, remaining below the recommended recreational threshold for human contact.

"Protecting the health of our visitors and their pets is our highest priority," said Dan Kirmer, John Martin Reservoir State Park Manager. "This advisory is limited to the west boat ramp cove, and we'll continue monitoring conditions closely while providing visitors with the latest information. We appreciate everyone's cooperation as we work to ensure the area is safe for recreation."

Colorado Parks and Wildlife will continue routine sampling and public education while the advisory remains in effect. Because blue-green algae conditions can change quickly depending on weather, water temperature and other environmental factors, visitors are encouraged to pay close attention to posted advisory signs throughout the park.

At this time, visitors should avoid entering the water where algae is present, particularly in the west boat ramp cove. Pet owners should keep dogs leashed near the shoreline and prevent them from drinking the water or contacting visible algae or dried algae along the shore. If accidental exposure occurs, people and pets should rinse thoroughly with clean, potable water as soon as possible.

Fishing opportunities elsewhere at John Martin Reservoir remain available. Anglers should avoid unnecessary contact with areas where algae is visible and follow all posted advisories.

Blue-green algae are a natural part of aquatic ecosystems, but some species can produce toxins that may pose health risks to people and animals when present at elevated concentrations. While testing provides an important snapshot of current conditions, algae blooms and toxin levels can change over time and may vary across different areas of a reservoir.

Anyone experiencing symptoms such as nausea, vomiting, diarrhea, skin irritation, difficulty breathing or other unexplained illness following contact with reservoir water should seek medical care. Pet owners should contact a veterinarian immediately if their animals become ill after water exposure.

Current advisories and updates will also be posted on-site at affected access points as monitoring continues.

Home News Releases Localized blue-green algae advisory issued at John Martin Reservoir State Park Localized blue-green algae advisory issued at John Martin Reservoir State Park Southeast Region Share: Dean Miller Southeast Region Public Information Officer 719-466-3927 [email protected] A loca...

08/03/2026

Don't forget today is free entry to Colorado State Parks!

08/01/2026

Join us at noon tomorrow for Colorado Day!

07/31/2026

Colorado Day is this weekend, so celebrate with free entry to all Colorado State Parks on Monday, August 3rd! Veterans and Active duty military also get a free park pass for the whole month of August (must bring a valid military ID)