Several metro cities will try a pricey new brown salt on icy streets this winter.
The promise is that it will melt snow and ice at lower temperatures than straight salt - and that less of it will be needed to do the job. Minneapolis, St. Paul, Burnsville, Savage, Lakeville and possibly Edina plan to test the product, which is made by Cargill Deicing Technology at a plant in Savage.
"It's easy to listen to a salesman tell you how wonderful it is, but we want to see for ourselves," said Gary Erichson, St. Paul street maintenance engineer.
Cargill says its salt has been treated with magnesium chloride to make it melt ice at lower temperatures than regular salt.
It also is coated with brown sugar cane molasses to help it stick to the pavement. Regular rock salt has a tendency to bounce and blow on the road.
Maintenance officials estimate that the treated salt costs about $45 per ton, compared to about $30 for a ton of regular salt.
"It's more expensive, so it's going to have to work," Erichson said.
Cargill contends that although the treated salt costs more than regular salt, less of it is needed. Moreover, fuel and labor savings keep the overall cost about the same.
Indianapolis found that to be true in a test conducted during last year's mild winter. Officials there found they needed about one-third less of the Cargill brown salt to do the same job performed by regular salt, said Steve Pruitt, acting operations manager of the Indianapolis Department of Public Works.
"The one-third savings that they say that you get, we did achieve that," Pruitt said.
The savings resulted from the fact that the treated salt did not clump in the back of the truck like regular salt, making it easier for operators to control its flow from the truck and use less, Pruitt said.
One truckload of the brown salt could be used to finish a route, while drivers with regular salt had to return and reload, Pruitt said.
He also found that the brown salt had a lasting, residual melting effect that was reactivated by subsequent snowfalls. Streets treated with the brown salt looked wet when it snowed and the streets treated with regular salt looked snow-dusted, he said.
"We had a hard time convincing people that we were still putting salt down because they didn't see white streets," he said.
Once residents adjusted, Pruitt said, "We had excellent reviews on it. We had fewer calls about tracking salt into the house."
Pruitt also noticed less corrosion on the trucks from the product and less grass kill along streets where it was tested because it did not bounce onto the curb.
How low can it go?
But the Indiana weather never turned cold enough to test Cargill's claim that the brown salt melted ice at low temperatures. Cargill says the product melts ice down to 5 degrees.
Minneapolis is especially interested in its low-temperature melting capabilities, said Mike Kennedy, director of field services for the city's Public Works Department.
"Occasionally we will get conditions where it never gets above 5 degrees. Perhaps that's a time when this product will be a benefit," Kennedy said.
To market the product in the metro area, Cargill sent salespeople to talk it up with maintenance officials and invited them to a briefing at the Savage plant.
The cost has kept Edina on the fence about using it, said public works coordinator Steve Johnson.
Doug Hartman, street supervisor for Burnsville, said he decided to try the product because the City Council wants to get more aggressive with snow and ice removal.
"Last year we lowered our plow threshold" from two inches to one inch of snow, Hartman said.
Big new park-and-ride
opens in Blaine
The metro area's newest park-and-ride lot opened this month in Blaine with 800 parking spaces.
At the intersection of Interstate Hwy. 35W and 95th Av., the new lot can be seen from the freeway, situated right at the point where southbound traffic stacks up in the morning, said Metro Transit planner Cyndi Harper.
That visibility could be why the lot is filling up quickly. Since its opening on Dec. 9, roughly half the parking spots have been occupied, said Bob Gibbons, customer services director for Metro Transit.
The $3.5 million lot was built by the Minnesota Department of Transportation and will be operated by Metro Transit. Former Transportation Commissioner Elwyn Tinklenberg said he initiated the project and is gratified by the quick response from commuters.
This lot is the northernmost park-and-ride operated by Metro Transit. Similar outlying park-and-ride lots should be located all around the metro area to reduce freeway congestion, Tinklenberg said.
Next month, residents living along I-35W north of the lot will receive fliers announcing the service and offering a free ride coupon, Gibbons said.
Before the lot was built, commuter demand swamped a 50-space parking lot at the same location and more than 150 cars spilled onto side streets. Commuters were moved in March to a temporary park-and-ride at a nearby Home Depot so the new lot could be built.
Feeling pressure to get commuters back to the original location after nine months of displacement, Metro Transit opened the new lot with two shelters (one heated). A more elaborate indoor waiting station is in the works for next fall, Harper said.
The lot provides a direct connection to I-35W for southbound buses. Once on the freeway, the buses get around traffic by taking shoulder lanes most of the way, Gibbons said.
Using a federal grant, Metro Transit has doubled bus service for commuters using the new lot since it opened. There are now a total of 26 trips southbound each morning to downtown Minneapolis and St. Paul.
YOUR VIEW
METERS NEED SOME TWEAKING
I support the ramp meter program if it works properly. During the past month, the meters at Rockford Road east and Hwy. 169 south were changed from switching on at 6:30 a.m. to about 6:20 a.m. This was not a problem. However, the cycle time has consistently been around 15 seconds no matter how much traffic is southbound on Hwy. 169. The traffic does back up at this ramp at 6:30 a.m., causing unnecessary delays. Once I am on Hwy. 169, the traffic is moving at a steady 55 mph. What is the problem?
With traffic moving at the speed limit and with less traffic than in the middle of the day, there should be almost no waiting at this light.
I've also noted a problem with the ramp from Interstate Hwy. 394 west to Hwy. 169 north in evening rush hour. Often this light is cycling so rapidly that there's no waiting traffic, but Hwy. 169 is at a standstill.
I think [the state] still has some more adjustments to make on some of these lights.
- Raymond E. Beauchamp, Plymouth
- We'd like to hear your tales from the road, comments and questions. Send e-mail to Getting
there@startribune.com or write to Getting There, Star Tribune, 425 Portland Av. S., Minneapolis, MN 55488. You may also leave a comment at 612-673-9016. On all messages, please give your name, city and daytime phone.
DO YOU KNOW ...
WHAT ROAD SIGN COLORS MEAN?
The background color of road signs indicates their purpose.
Red is used to prohibit and command.
White is used to regulate.
Yellow is used for warnings.
Yellow-green is used to control pedestrian and bicycle crossings.
Orange is used to control construction zones.
Green is used to guide and inform.
Blue announces services for motorists.
Brown directs motorists to historic, cultural or recreation sites.
Source: Minnesota Department of Public Safety
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