McMaster University's Lot M has served as an overflow parking lot for decades, and a giant man-made barrier between the Dundas Valley Conservation Area (DVCA) and Cootes Paradise for just as long.

That barrier is about to be removed, albeit slightly.

On Saturday, teams of volunteer students were busy making sand berms for turtle nesting grounds on a slice of the parking lot, roughly 20 metres wide that stretches just under 1 km long, that has been uprooted to create a larger natural area buffer around Spencers Creek.

And on Thursday, Hamilton Naturalists' Club (HNC) will be on hand with staff from Canon Canada to plant native trees, too.

As far as environmentalism goes it's a rapid reconstruction of the riparian zone, a process that was first mentioned in 2009, but was only suggested until recently, meeting little to no resistance from McMaster.

"Thinking sustainable is a challenge," said Dr. Susan Dudley, a professor at McMaster's biology department. "We're not saying there shouldn't be parking … We can make sure we're resetting the parking lot to make it more sustainable."

Built to a old standard, and fixing a past mistake

The parking lot is situated between Cootes Paradise and the DVCA, and was built 10 metres from Spencers Creek — a rare cold water creek that supports a unique set of life. It leaves a small area for wildlife like deer and turtles to cross between Cootes and the DVCA. Dudley said many creeks have lost the riparian zone — the area of foliage which shades and spreads out from the creek — from mostly human cut backs, like farming to name one example.

"It's a rare habitat now," Dudley said of the cold water creek.

Without the shade, the temperature of the creek heats up, and the organisms that can survive do, too. A 10 metre buffer was the old standard from decades ago, but McMaster has since adopted a 30 metre buffer around creeks for development.

"When they designed the parking lot they're not thinking about the creek, they're mostly thinking about preventing flooding," Dudley said.

Implementing a change to Lot M would require McMaster to slice a significant chunk off the back of the parking lot. The plan was first mentioned in 2009, according to a time line from a local environmental group, Restore Cootes. McMaster had been working on a sewer overflow tank, and looked at possibly cutting back the lot to stay in line with the 30 metre buffer policy. Through the next few years, the issue was sent to the President's Advisory Committee on Cootes Paradise where it sailed through, and in August 2013, the pavement was ripped up.

Student volunteers dig in

Reyna Matties gives instructions to some two dozen volunteers who showed up at Lot M Saturday morning to make turtle nesting grounds. (Jeff Green/CBC) A little more than a year later, Reyna Matties, a research assistant from Dudley's lab, was directing two dozen student volunteers to piles of sand and wheelbarrows. Some had not heard of the turtles which are run over on Cootes Drive, the same turtles they would be building small half-metre tall nesting mounds over top the torn up parking lot.

In all, four berms for turtles will be built. They'll sit at the back of the parking lot, juxtaposed by the "one way" signs, street lamps and security camera poles that were not removed, and now sit awkwardly in the middle of a riparian zone.

On Thursday, Giuliana Casimirri, the urban forest project coordinator for the HNC who holds a PhD in community-based forest management, will be directing staff from Canon Canada to plant trees.

And in the future going forward, Dudley will be monitoring the progress of riparian zone, taking measurements of how the new 20-metre wide section is doing year after year with her field work class.