New pavement keeps Lake Superior-bound
By Craig Lincoln
Duluth News Tribune
Leaky pavement may be one solution to a sticky development
problem in Duluth.
That's the hope, at least, of the city and the company
developing a London Road parcel.
A&L Properties is using a new form of concrete paving
block to develop its London Road property at 17th Avenue
East. The block is designed to eliminate runoff from parking
lots and clean the water before it reaches Lake Superior.
Runoff from paved parking lots has gained the attention
of regulators and environmentalists.
Pavement heats up water and loads it with sediment and
grime before shooting it pell-mell into streams and lakes.
Surface runoff is now one of the bigger sources of water
pollutants in the nation.
"If this works out, we're going to try to encourage
other commercial developments to use it within shoreland
zones," said Jim Mohn, a Duluth city planner.
And in Duluth, a shoreland zone is a big deal. Any development
within 1,000 feet of Lake Superior or 300 feet of a river
or stream is considered to be in a shoreland zone. That
includes a lot of Duluth's commercial land, such as Park
Point, downtown and the Miller Hill corridor.
"In new projects, this is absolutely the type of
things they should be doing," said David Zentner,
chairman of the Miller Creek Joint Powers Board. The board
is a partnership between Hermantown and Duluth created
to help protect Miller Creek from being damaged by development.
"So much of the conflict in the environment is to
try to get people to change their behavior, even if just
a little bit," he said.
The lot, about 110 feet by 150 feet, will the site of
the new St. Germain's paint store. The store is being
moved from 1021 E. Superior St. to make room for a St.
Luke's Hospital expansion.
The developer, A&L Properties, built Duluth's Technology
Village and many other recent developments. Without the
special paving blocks, developing the London Road lot
"would have been challenging," said Mike Kratt,
property manager for A&L. "We probably could
have pulled it off, but this certainly helped."
The paving blocks, called a Uni Eco-Stone system, are
shaped like octagons. When fitted together, they leave
small square holes all over the parking lot. The holes
are filled with gravel, which allows water to drain and
serves as a filter.
The surface is on top of gravel or a pipe system, depending
on what works best for each site, said Craig Olson of
Borgert Products Inc. of St. Joseph, Minn. Borgert distributes
the paving block.
As the water percolates through the gravel, sediments
are filtered out and it cools down, Olson said.
The paving block is more expensive than regular pavement.
It's difficult to say how much, because each parking lot
requires different base layers and engineering.
"If we can start with one drop and start recharging
that water, problems with clean water will be solved,"