When Alex Williams starts his shift as a senior Denver park ranger, he rarely knows where the day will lead.

“I just, earlier this morning, found what looks like a whole apartment that was just dumped on the South Platte,” he said Monday as he drove through downtown Denver. “There’s an organ. There’s a couch.”

His usual patrol route for the Denver Department of Parks and Recreation takes him along segments of the South Platte River and Cherry Creek trails. He collects dumped trash, reports electric scooters he finds submerged in the water, and offers garbage bags and socks to people living in encampments before directing them elsewhere.

Denver’s park system is made up of about 20,000 acres of parkland, including more than 250 urban parks and over 80 miles of trails in the city. In such a large system, Williams and about 65 other rangers have amassed anecdotes about strange — and even risky — encounters in their assigned districts throughout the city and county.

And then there are the oddities they find in the waterways.

The list of anomalies removed from Cherry Creek alone include a wheelbarrow and a hairless guinea pig — a pet that escaped its owners on the trail, said Parks and Recreation spokesperson Stephanie Figueroa. The guinea pig was found alive.

Last week, Williams, 36, helped extract a moped from the creek.

“It’s pretty common to see something like that,” he said.

Sometimes, an abandoned vehicle turns out to have been stolen, Williams said. Rangers look up its license plate or vehicle identification number to confirm. Other times, it’s been ravaged for parts, and the remains are left in a local park.

When rangers find Lime and Lyft electric scooters in Cherry Creek — a frequent occurrence — they report the locations through a phone app that alerts company technicians to collect them.

Homeowners and contractors also have a habit of dumping construction materials in these public spaces.

“With waste fees and landfills being what they are, it’s just enticing to dump it wherever it seems convenient,” Williams said. “Often, that’s a secluded part of the trails district or another park.”

At the start of July, he was finishing his final week of medication — a cautionary measure after he was poked by a needle. It was hidden in a blanket that he came in contact with during a hazardous materials cleanup in the undergrowth along the Cherry Creek Trail.

“The risks of the job,” he sighed.

On Monday morning, Williams sat behind the wheel of his park ranger car, its lights flashing. In the back seat, park ranger manager Jodie Marozas, 41, was ready for anything they might encounter — with a baton, a can of pepper spray, a flashlight and a radio on her belt, along with naloxone in her bag (to reverse opioid overdoses) and a pocket knife in her cargo pants.

As Williams merged onto the tight path at a junction of the South Platte River and the Cherry Creek trails, he greeted cyclists through his open window. There, he’s a familiar face. Several passersby stopped to chat.

He quickly spotted a violation in Confluence Park: a man throwing a ball to his off-leash dog in the water. Williams recognized him as a repeat offender.

Rangers enforce dozens of park-specific statutes, including rules regulating off-leash dogs, dumping, fireworks, fires and more. They follow a progressive compliance model, leading with education before taking further steps: a written warning, then citations, with fines that can increase.

Williams and Marozas approached the dog owner, who immediately began arguing and cursing. Saying he was a lawyer from Maine, he continued tossing the ball to his dog as Marozas tried to write him a citation. Finally, he put his pet on a leash, yelling as he stormed away.

“Usually, people that are breaking park rules aren’t very happy seeing us,” Marozas said. “In those situations, yeah — that is kind of the reaction we get.”

She emphasized the importance of de-escalation tactics because aggressive interactions aren’t uncommon for rangers. They learn Krav Maga, a self-defense-oriented martial art, with eight hours of training required annually.

Recently, a person chucked a scooter at a ranger, which caused a shoulder injury, Williams said.

“We get yelled at. We get called the meanest things you can imagine,” he added.

During the summer, parkgoers wade into the water at Confluence Park — though, “technically, you’re not allowed to swim in any of the waterways,” Williams said. “I’ll always tell the folks here that the water quality is not particularly good.”

For years, city officials have warned residents about potential exposure to contaminants and other risks, including E. coli, in the river.

In Williams’ opinion, the ideal ranger needs to be outgoing. On a daily basis, he interacts with people from all walks of life, including those experiencing homelessness.

On the Cherry Creek Trail, rangers ask people camping underneath the bridges to relocate because they’re in areas considered closed, in part for safety.

Periodically, rangers have to alert people in encampments about the U.S. Army Corp of Engineers’ scheduled flushes of the Cherry Creek Reservoir, which can potentially leave them stranded, or worse, when the trail floods.

During his patrol, Williams approached a man sitting in a chair under an overpass, his backpack and rolling suitcase at his side.

Next to him, a sign read: “No overnight camping.”

After Williams informed the man that it’s a closed area, he offered him a bottle of water.

“Is it Fiji?” the man responded, before gathering his belongings.

Several spots on the waterways are considered “problem areas,” or places with high numbers of violations, such as Creekfront Park near Larimer Square.

Half a dozen men slept on benches or listened to music throughout the park. Marozas approached a person who was holding a glass pipe to warn him about two violations: public marijuana use and glass. But for the most part, the pair of rangers conducted welfare checks.

“When we’re talking to the unhoused community, it’s not because we’re harassing them. It’s typically because we’re giving them resources,” Williams said. Along with water, his team passes out socks. Rangers give out beanies and hand warmers during the winter.

To Denverites who use local parks and trails, Marozas reminds them: “Take pride in the space that you use.”

And also, she says, laughing: “There isn’t a dog poop fairy.”

Get more Colorado news by signing up for our daily Your Morning Dozen email newsletter.