TH 282 – Street & Utility Reconstruction
Project Description
TH 282, also known as 2nd Street, will be reconstructed from Creek Lane to Mill Street during the summer of 2009. This will include replacing the signal system at the intersection of TH 21 and TH 282 and adding a left turn lane for eastbound TH 282. The storm sewer will be extended to alleys north of TH 282 to alleviate some existing drainage problems. Also, watermain will be added on Wood Street, West Street and Varner Street just south of TH 282 to eliminate some long water services.
The sanitary sewer and water mains under TH 282 are the original infrastructure installed in the City of Jordan during the 1920’s. The sanitary sewer is a clay pipe. This pipe was installed in sections that are 3’ long. This leaves a joint every 3 feet that tree roots can grow into and that can separate and allow groundwater to enter the sanitary sewer system. If groundwater enters the sanitary sewer system, it is treated along with the sewage at the wastewater treatment plant. This costs taxpayers extra money to pay for the chemicals to treat clean water. The watermain is a 4” cast iron pipe. A 4” pipe size is too small to meet today’s capacity standards for fire fighting. Also, due to the material of the pipe and the age of the pipe, the pipe has become very brittle. City maintenance crews have to repair numerous watermain breaks in this pipe each year. In addition, some of the water service lines from the watermain to the houses are constructed of lead pipe. Lead pipe is a source of lead in water in homes, and is no longer allowed to be used in construction.
These types of conditions existed throughout the lowertown area of Jordan. The TH 282 project is the last project in a series of projects the City has undertaken to update its infrastructure. After this project nearly all of the sanitary sewer in the lowertown area will be constructed of PVC piping which has a joint that will not allow groundwater into the pipe. This will save taxpayers money on treatment costs. The watermain will be constructed of 8” ductile iron pipe. This will provide sufficient flows for fighting fires in this area, and save taxpayers money on repairing watermain breaks. Replacing the lead water services will provide property owners the opportunity to replace any remaining lead lines in their homes and have lead free piping supplying the water to their homes and businesses.
The streets are also in poor condition. For many decades, MnDOT has added bituminous overlays on top of the existing gutter. This has resulted in the bituminous covering up the 6” high back of the curb, and now there is little curb left to carry the drainage properly. Also there are “bird baths” that form after rainfalls, indicating improper drainage. During freeze – thaw cycles these areas break up the bituminous surfacing. The condition of the street has reached a point where maintenance procedures such as seal coating or milling and overlaying are no longer cost effective. This combined with the need to replace the utilities beneath the street are the reasons that the street will be fully reconstructed.
The existing street width varies, but is generally about 46’ wide on average. The new street width will be 46’ between the faces of the curbs. Normally the minimum design width for this street would be 48’ between the faces of the curbs. However, MnDOT is allowing the substandard street width so that the vast majority of the trees can be saved.
The concrete curb and gutter will be replaced throughout the corridor as well as the concrete walk. New concrete walk is proposed to be constructed along the north side of TH 282
between Mertens Street and Creek Lane.
All existing driveway aprons will be replaced with new concrete aprons between the street and sidewalk to match the existing driveways to the new street grades. Sidewalks will be thickened to a 6” depth thru driveway areas to help ensure less damage from vehicle loads. The existing street signing, including stop signs and street name signs, will be removed and reinstalled by the contractor as necessary.
The pedestrian curb ramps will be constructed with truncated dome detectable warning systems in compliance with the Americans with Disabilities Act (ADA).
The existing trees will be protected from the construction as much as possible. Due to the mature nature of most of the trees, some of the canopies will require trimming during utility excavation. The areas disturbed by the construction will be re-graded to match the new street grades and restored with sod. Also, boulevards will be re-graded to help improve drainage where necessary.