Andrew Paule, flashlight in hand, bulging courier bag bouncing off his shoulder, bounded up the embankment under the Bloomington Avenue bridge over the Midtown Greenway in Minneapolis the other night, greeting three wary men with his customary hello.

"How are you doing?" he said. "Anybody need Narcan?"

Thus began a night out with Trail Watch, the volunteers of the Midtown Greenway Coalition who ride the Greenway and some adjacent trails at night to keep the place safer, cleaner and friendlier. And, these days, to keep people alive.

Narcan is the opioid antidote used to revive narcotic overdose and, late at night, the people who live under bridges and in the undergrowth along the Greenway rely on it in bunches. The men under the Bloomington Avenue bridge certainly did, along with sharps containers, extra needles and "clean use kits" that make it safer to shoot up.

"Welcome," Paule said once he was back at his trusty Bianchi, "to the unknown world of Minneapolis."

The Midtown Greenway is a marvel of municipal opportunism. It transformed an ill-used, 6-mile-long railroad ditch into a busy crosstown bike route that connects scores of trails, lanes and routes that take riders to all points on the compass. The coalition — a nonprofit collaboration that protects and advocates for the trail — figures the path is getting a million rides a year.

The complication is that at its midsection — away from the Chain of Lakes in the west and the Mississippi River to the east — the rail corridor has always sheltered large, shadow populations of street people. Anyone who rode the trail in its early stages, before it even was paved, won't forget the myriad eyes under the bridges and in the thickets that watched the new intruders cruise by on their Surlys, Scotts and Schwinns.

And, at the start, there were confrontations, which in 2006 inspired Paule and some of his friends at MPLSBikeLove.com to start night rides that evolved into Trail Watch. The idea was to create a friendly nighttime presence, keep an eye on things and clean up broken glass. It has endured with volunteers' commitment, with a few interruptions, ever since, and rolls once a week.

Paule, 59, a buoyant aerospace physicist who lives at the eastern end of the Greenway, is the de facto, though officially undesignated, leader of Trail Watch. "He has gone way, way above and beyond the call of duty" in the work, said coalition executive director Soren Jensen. Paule is now part biking ambassador (he waves hello to everyone he passes), part pedaling superintendent (he's ridden or walked most every inch of the place), and part social services coordinator (he said he's revived three people with Narcan so far this year, one of them on his way to work).

So as night fell, he alerted Minneapolis police dispatch of his intended route and, with six other volunteers, headed out. They would over the next several hours wave to commuters, clean up garbage, mingle with several dozen street people they met along the way, and look for clues to the state of the Greenway. With flashlights, they looked for piles of orange plastic tops to needles, people in distress and the remnants of bikes, stripped for their salable parts.

And, all things considered, they'll tell you the Green­way's been quiet. In the spring, the volunteers were filling two sharps containers with discarded needles in a night; now they rarely fill one container over several trips. And Jensen, who looks at the police reports every week, said, the crime rate on the Greenway is "very low."

"The neighborhood has some problems, but they do not spill out onto the trail," he said.

But the Greenway's unavoidable dynamic is that it is an urban trench, with nowhere to go on the rare occasion when people ride into trouble. That was the case when, on a morning in July, a woman swinging a length of rope attacked a woman on a bike, leaving a welt across her back. Jensen said one such attack a year happens; some years there are none.

At one stop the other night, with a group huddled under a streetlight north of the Martin Olav Sabo Bridge, Paule and his team were handing out sharps containers, Narcan, bottles of water and clean needles, when a woman suddenly said, "Who are you?"

Paule showed her his Trail Watch vest and said, "We're just a bunch of bike nuts, picking up glass and trying to keep the trail safe."

"Cool!" said the woman as she opened her bottle of water and took a long drink.

Bike note

After a raucous public hearing and months of intense civic debate, the Minnetonka City Council last week approved a plan to introduce 5 miles of mountain-biking trails to the city's Lone Lake Park. People who explore the park on foot are feeling besieged by bikers. Bikers feel attacked by unfounded fears. Will they use the winter to get to know each other before they share Lone Lake? Guessing not.

Tony Brown is a freelance writer from Minneapolis. His column appears twice a month. Reach him at mplsbikeguy@gmail.com. Read archived columns at startribune.com/bikeguy.