Minneapolis prepares to double what it has been spending to repair storm tunnel outlets.
The 128-year-old horseshoe-shaped storm tunnel outlet on 10th Avenue with its tan and red brick floor isn't in horrible shape, reported The Star Tribune however, it and others like it are in danger of cracking and blowing-out if left in their current condition.
According to The Star Tribune, the city will double the $3.5 million it is spending annually on repairing the tunnels to widen tunnels like the one on 10th Avenue. This means that Minneapolis homeowners, currently paying $11.09 a month towards maintain the drainage system will find themselves paying $12.41 monthly by 2015.
The 14.7-mile tunnel system was constructed in an era of pre-urbanization, when unpaved streets and yards soaked up most of the rain that fell on the city, wrote Steve Brandt of The Star Tribune. Now the tunnels must deal with a lot more water than they were originally built to withstand.
Inspectors periodically look for new cracks and monitor old ones in an attempt to gauge whether or not escaping water is wearing down the supporting sandstone. According to Kevin Danen, an engineer heading up city sanitary and storm sewer construction and maintenance, damage can happen quickly, forcing repairs.
Analysis: Though temporary repairs are made on a regular basis, the tunnels are in dire need of refurbishment. If left unchecked, eroding storm sewers could potentially pose a threat to Minneapolis' infrastructure. The money will come out of homeowner's pockets in a plan that not only increases its baseline fee but will steadily increase by a nickel or so per month. By 2015, homeowners can expect to be paying at least $12.41 monthly. The increase will be a gradual one however, and will likely go unnoticed unless cost rise above initial estimates.