I-68 Drainage Repairs
Allegany County, MD
The project involves the repair / replacement of three storm drain pipes and outfalls along a section of Interstate 68 in Allegany County. All three pipes are corrugated metal and each exhibits similar deterioration along its length. The corrugated metal pipes have deteriorated over the years since their initial installation during the construction of I-68 in western Maryland. The deterioration of the pipes has led to holes in the pipes and joint failures, resulting in surrounding embankment erosion and soil infiltration. The outfalls for each of the three pipes exhibit deep cuts from continuous erosion.
The following tasks were performed for this project:
• Video inspection of the existing pipes from the inlets in the median of I-68 to the outfalls along the roadway embankments. Video inspection was used to determine the extent of deterioration for the entire lengths of the pipes to determine whether spot repairs only would be adequate or entire replacement was warranted.
• H&H analysis was performed for design of the storm water repair / replacement options (i.e. actual required pipe sizes for drainage conditions). Several options were analyzed including: retrofitting the existing pipes with linings, remove and replace entire length of pipes, abandon some of the inlets and divert flow to others, etc.