As psychedelic healing centers prepare to open in Colorado this spring, Denver has decided it will impose some local rules for the programs beyond the state’s requirements.

Under the city’s ordinance, which the City Council approved unanimously Monday, businesses interested in operating centers where people can take psychedelics under supervision will be required to apply for both city and state licenses.

“We, in Denver, led the way in cannabis legalization, and we also led in regulating it responsibly to ensure long-term success,” said Councilman Chris Hinds. “This is the same kind of thoughtful, risk-averse progress that allows natural medicine to be a sustainable part of our city’s future.”

The new rules come after Colorado voters in 2022 approved Proposition 122, directing the state to develop regulations for psychedelic-assisted therapies. The proposition also decriminalized possession, personal use, growing and sharing of five psychedelic substances: psilocybin, psilocin, DMT, ibogaine and mescaline.

In part, the city decided to develop its own local licensing program because there is potential for facilities to open that offer psychedelics to more than 60 people at once — as long as there are enough supervisors for them.

That could mean retreat centers, yoga studios or social clubs could offer the treatments.

“These could allow for healing centers that operate a little bit more like a social venue. That’s where we’ve identified potential community impacts and risks that we want to be able to mitigate through a local license,” said Abby Soisson with the Denver Department of Excise and Licenses in a February committee meeting.

Psilocybin, which is still a federally-controlled drug, has long been used for unsanctioned therapy, but recently, it has become more mainstream as a treatment for major depression and post-traumatic stress disorder.

Under state regulations and city zoning restrictions — including a 1,000-foot-buffer zone for schools and child care centers — spots where the healing centers can open will be sparse.

A map provided by city officials shows patches mostly along Interstate 25 and in northeast Denver where the programs can open. Some Front Range cities, like Boulder and Colorado Springs, have tweaked the state requirements to loosen or tighten requirements around where they can operate.