How do you get pedestrians and floodwater from N. Main St. to the Huron River? In 2007, the city’s Jerry Hancock had the answer: Go under it. Now, after a decade of planning, the city finally has the green light to launch a project that will transform the cramped corridor.

Every day, runners and walkers cut illegally across the Amtrak railroad tracks to reach the river. Because the tracks cross buried Allen Creek on a berm, in heavy rains they also function as a dam. When the creek overflows its underground pipe—as it does every few years—the water backs up, endangering low-lying neighborhoods on Depot and E. Summit.

The solution: build a combination pedestrian/bike tunnel and floodwater conduit under the tracks. But with the cost estimated at $6.8 million, bringing the Allen Creek Railroad Berm Opening to reality took more than a decade of planning and fundraising. The last piece fell in place in early June, when DTE granted a key easement on its property across the tracks.

Hancock, the city’s stormwater and floodplain programs coordinator, first conceived the idea of cutting a channel under the railroad in 2007, when the city got a $70,000 FEMA grant to study floodplain mitigation. At a staff meeting, city transportation chief Eli Cooper reportedly had a eureka moment when he heard about it, realizing pedestrians and bikers could use the cut-through, too.

From then on, it became a “kill two birds with one stone” project, says U-M law prof David Santacroce, who chaired a city task force on the N. Main corridor. “We liked the idea,” he says. “It was the right place, it was safe, you could ride your bike [through it], you could walk.”

The city hired OHM Advisors and J. Bergman Consulting to do a feasibility study, and they came up with a doable design. But how to pay for it? Ironically, Mother Nature provided an unexpected answer in the summer of 2014: heavy rains flooded much of Detroit, prompting a federal disaster declaration for Michigan. After the cleanup, the leftover funds were made available for flood-abatement projects statewide. The city raced to complete its grant application in a narrow two-month period late that year.

In the end, FEMA provided $4.8 million of the estimated $6.8 million cost. Other funding includes $300,000 from the state DNR trust fund and a $1 million MDOT Transportation Alternatives Program (TAP) grant. MDOT, which owns the tracks, is concerned about the illegal crossings—always risky, they’ll be even more dangerous once Amtrak starts running high-speed trains between Detroit and Chicago. As part of the deal, the city has agreed to fence the tracks along N. Main to direct crossers to the new tunnel.

The final $700,000 will come from the city’s transportation budget—which means the city will pay little more than one-tenth of the total cost. But with both the TAP and FEMA grants expiring next year, the DTE easement came just in time.

“We at DTE are very excited about this project,” says Bruce Peterson, the utility’s general counsel, who headed the negotiations with the city. The thirteen-acre parcel off Broadway, originally an illuminating-gas plant, “has been waiting for a purpose—we were seeking the highest and best use for it.”

First Martin Corp. also granted the city an easement for use of its property during construction. “For us, it’ll provide immediate and substantial stormwater relief in an area that needs it,” Mike Martin says. The berm opening would lower the floodplain along Depot by six-and-a-half feet. After the project is finished, the city plans to draw up a new floodplain map to delineate a radically altered landscape.

The tunnel will also link the long-­anticipated Allen Creek Greenway, now known as the Treeline, to the county’s Border-to-Border Trail.

The construction schedule must be built around closure of the Amtrak tracks for a single day. Hancock says bids for the project can go out this fall—followed by a series of city council hearings and public meetings to complete the necessary approval process. If there are no snags, construction would start next spring.

Meanwhile, DTE is working with ­Detroit-area developer the Roxbury Group to redevelop its property. Peterson says they’re looking at a retail-­residential-recreational complex that would include condos, river-facing restaurants, a possible hotel, and a retail pavilion “like the ones at Eastern Market” in Detroit.