Millennium Park to get new playground, repaved paths, maybe even restrooms; work faces unique challenge because park is a methane-producing former landfill

The Boston Parks and Recreation Department and a civil-engineering firm have started redesigning the 20-year-old playground near the top of Millennium Park in West Roxbury in a project that could also mean replacing the park's seasonal portable toilets with a more permanent restroom building.

The department and CDM Smith - which didn't need to get up to speed on the park because it was involved with its original formation above the former Gardner Street landfill - held a public meeting tonight to introduce the project and to seek ideas for what the new playground should look like.

Parks and Recreation hopes to have a new playground in place, along with repaved paths around the park and possibly the new restrooms, by next summer.

Although tonight's meeting was meant to hear what park users might want, engineers from CDM Smith - who also worked to refurbish the fields at neighboring West Roxbury High School in 2015 - laid out some possibilities, starting with replacing the current playground, assembled out of pre-fab stuff from a factory, with something that both presents more play challenges for kids of all abilities, which could include everything from "interactive water elements" to seesaws to permanent play houses.

And ideally, the new playground area should take advantage of the hill's terrain, they said. Glenn Howard, the company's landscape engineer, posed the idea of a slide or other features that run down the hill from the current playground area to the land down below, near soccer-field B.

Other ideas would include ripping out the fences that now separate the young-kid area, the swings and the older-kid are with hillocks or even wood blocks that would offer separation for kids and parents who want them but which would also present a play challenge for other kids.

The company is looking at the possibility of putting a permanent restroom building in an oval-ish area near the current playgrounds, across the upper parking lot from the frame where the city installs portable toilets in the spring.

Bob Button, the company's vice president and himself a civil engineer, who has now spent 26 years on Millennium Park-related projects, said the oval, where the park's one water fountain is located, already has water and sewer lines and an electrical conduit - put in during the park's construction in the late '90s for just this reason.

Button said the design would be done so that the area could continue to be used as a check-in area for the soccer leagues who uses the park's fields.

And he added that any building would have to be designed to account for both the fact that it would sit just a few feet above the plastic liner that now surrounds the 50 years' of Boston trash that was dumped there and the fact that that trash gives off methane, which potentially could accumulate in unhealthy concentrations in an enclosed building, despite a series of pipes designed to capture methane and transport it down the hill to the city public-works area, where it is burned off and then vented through a smokestack next to the road to the park canoe launch.

Button said there are ways to keep the air inside the restrooms safe, for example, by putting the building on a platform raised above the ground, to create an "air gap" between the landfill and the interior of the building. He said any design would have to be approved by the state Department of Environmental Protection before it could be built.

Howard said there would be a potential issue with the landfill liner with a slide - and steps for parents - down to Field B. He noted that there's already a looming issue with people wearing away the topsoil along one potential slide path by using the hillside to get to and from the field from the higher location, rather than using the existing paved paths.

The engineers and Parks project manager Allison Perlman said they are not sure that repaving the current paths could include widening them to allow bicyclists to use them, again because of the potential issues and costs involved in building anything permanent on top of an old landfill.

Perlman said a video of the Zoom meeting will soon be posted on a project Web page. She said at least two more public meetings are scheduled, with one in March devoted to showing off more specific potential improvements.