MANKATO — Multiple intersections along Riverfront Drive will reach a failing point in coming years unless changes are made, according to a recently released study of one of Mankato's busiest corridors.
The yearlong study suggests a variety of fixes, including for the area around the YMCA and West High School and at the off ramp from Highway 14 where intersections already are causing significant back-ups during morning rush hours.
A roundabout at the intersection of Riverfront and Highway 14's westbound ramps could happen in the next few years, as could additional lanes to ease traffic flow around the back entrance to West High School and the YMCA.
Other potential changes, expected to take several years or even decades to implement, include realigning Third Avenue's intersection with Riverfront to tie directly into Madison Avenue; a northward extension of Stoltzman Road through what's now the Cub Foods parking lot; and pedestrian improvements in Old Town and downtown.
"Basically, the report is in," said City Manager Pat Hentges. "The council will be looking at it this summer."
The 79-page study, by consulting engineers Bolton and Menk Inc., lists more than $2 million in projects to be implemented in the next five years and as much as $2 million more in work in the ensuing decade.
In addition, projects totaling well over $10 million could be done as private development proceeds and planned pavement reconstruction of Riverfront occurs in coming decades. Possibilities include a pedestrian bridge for the West Mankato Trail near the YMCA and West High School, a looping exit ramp off of Highway 169 and roundabouts at Stoltzman, as well as the Highway 169 ramps.
Woodland Avenue to Sibley Parkway
The report recommends one of two options to improve traffic flow going into the YMCA and the West High School drop-off site.
The $700,000 first option would create three left-turn lanes from the Highway 169 southbound exit ramp on to Riverfront Drive.
"YMCA/school users will use the westernmost left-turn lane, Stoltzman Road users will choose the middle left-turn lane, and Cub Foods area users will choose the inside left-turn lane," the report states. "This should work well for local travelers as they become accustomed to which lane they should be in."
The $1 million second option would attempt to improve traffic flow by installing medians at Riverfront and Poplar Street that would eliminate all left turns except one — lefts into the YMCA/West High area from Riverfront Drive. Others looking to go left would need to turn right and, in most cases, do a U-turn at the Stoltzman intersection. That option also creates a new public street through the Cub Foods parking lot to Linder Street and possibly all the way to Sibley Parkway.
"Drivers are using this as a cut-thru today and formalizing this as a public street will improve the overall local network," the report said of the new street.
Just north of Cub Foods is a large lot that was formerly the home of Mankato's Public Works Department. Now vacant, the land is slated for private redevelopment of offices, commercial space or possibly residential housing.
"We expect that sometime in the next year the site would be cleared and ready for redevelopment," Hentges said. "Right now we're going through the investigation of any pollutants."
With either option, a mid-block pedestrian crossing would be added from West High to Cub Foods — with a pedestrian refuge in the middle of Riverfront. A second lane would be added to the northbound Highway 169 on-ramp so drivers turning left or right from Riverfront could enter the ramp simultaneously.
And northbound Stoltzman would get a fourth lane as it nears Riverfront — with dual left-turn lanes, a through lane into the Cub Foods area/new street and a right-turn lane.
"Either (of the two options) is expected to serve traffic operational needs ... very well for many years in the future," the report states.
It warns that larger improvements might be needed by 2041, such as a roundabout at major intersections such as Stoltzman and the Highway 169 ramps, if traffic levels increase as projected.
Also included in the report is another potential long-term project that would change the way southbound Highway 169 traffic exits onto Riverfront Drive. The project would involve building a loop ramp that would carry exiting traffic over Riverfront before looping down to Riverfront. Drivers, virtually of whom are looking to travel north on Riverfront, would then be able to make relatively easy right turns rather than making lefts as they must now.
Closer to downtown, the report recommends adding protected left turns at the Warren/Poplar Street and Cherry Street intersections with Riverfront, meaning the addition of left-turn lanes on Warren and Poplar and left-turn arrows on the semaphores at the intersections.
Those intersections also need to be slightly realigned because the cross streets on the west side meet Riverfront a few feet farther to the north than the cross streets coming from the east. That creates confusion for drivers, according to the report.
Pedestrian improvements at Liberty Street could include a "pedestrian refuge" in the middle of Riverfront and a flashing crossing sign.
A sidewalk is needed on the east side of Riverfront where a gap in the sidewalk system exists along a parking ramp and the Hilton Garden Inn, according to the consultants, who investigated the possibility of shifting Riverfront slightly to the north in that area. That would have relied on Hy-Vee rebuilding on a different footprint — something that managers at the supermarket said are not in their plans.
The free-right turn from northbound Riverfront to Plum Street would be eliminated. The study found the dedicated no-stop lane doesn't serve a meaningful purpose in keeping traffic moving and makes it more difficult for pedestrians to cross the street.
The needs of pedestrians are a primary goal in proposed changes for the Old Town business district. A pedestrian-activated flasher system would be added to either Rock or Elm streets, with the other street having a full semaphore.
A major part of the proposal involves possibly reducing the number of lanes on Riverfront through Old Town to make room for wider sidewalks, easier pedestrian crossings and curb bump-outs at intersections. (A story more closely examining that part of the plan will be in Wednesday's Free Press.)
Madison Avenue to Highway 14
One of the most significant changes proposed by the study would eliminate the connection of Third Avenue and Riverfront Drive, which has an above-average crash rate. The intersection is about 200 feet north of where Madison Avenue has a T-intersection with Riverfront from the opposite direction.
The Bolton and Menk consultants honed in on two possible fixes. One would curve Third Avenue to the south as it approaches Riverfront and tie it directly to Madison Avenue to create a four-legged intersection. The second would extend Madison Avenue into the quarry to the west and extend Third Avenue to intersect with the new segment of Madison.
Blue Earth County, which has jurisdiction over Third Avenue, indicated the idea is "a viable option," according to the report.
Neither of those options were a possibility until last year, when the Coughlan Companies — owners of the quarry — announced mining operations were being discontinued and the land would be redeveloped.
"Although they are still early in their planning process, the Coughlan representatives also felt this was a viable alternative for future study," the report states of the alignment of Third and Madison avenues at Riverfront.
If that four-legged intersection comes to fruition, it would also be worth studying whether the traffic signals at Madison and Riverfront could be eliminated, according to the report: "A multi-lane roundabout could be tested further in the future at the time when Coughlan Quarry redevelopment plans are available."
Most of Riverfront Drive north of Madison Avenue is performing well. In fact, the consultants suggested the city consider, before reconstructing that section of Riverfront Drive in the 2020's, whether such a wide road with so many lanes is needed.
On the north end, though, there's an immediate problem that might end up being one of the first projects from the study that's constructed.
Drivers exiting westbound Highway 14 looking to turn left on to southbound Riverfront are having a tough time, particularly during peak traffic times. And it's only expected to get worse. By 2041, each vehicle looking to making that turn could be waiting nearly a minute during peak afternoon traffic, according to the report.
The consultants said a roundabout would be the best solution, noting a second roundabout could be added at the eastbound ramps but is much less urgent.
Even if the Mankato City Council adopts the Riverfront Drive Corridor Study into its land-use plan later this summer, each individual project would have to go through the traditional funding and approval process, including public hearings.