Protection of Precious Waters From Road Salt: Mitigation Through Roadside Ditch Capture

Details

• Creators:
  Druschel, Stephen J.
• Corporate Creators:
  Minnesota State University. Center for Transportation Research and Implementation
• Corporate Contributors:
  Minnesota. Department of Transportation. Office of Research & Innovation
• Subject/TRT Terms:
  Backfill Soils Chlorides Deicing Deicing Chemicals Ditches Drainage Highways Sodium Chloride Water Quality Management Winter Maintenance
• Publication/ Report Number:
  MN 2026-07
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Minnesota
• Edition:
  Final Report
• Corporate Publisher:
  Minnesota. Department of Transportation. Office of Research & Innovation
• Abstract:
  Roadway deicers are essential to the functioning of daily life in northern states in winter. After plowing, roadway salting is currently the most practical way of making safe transportation possible in winter. However, road deicer chloride (salt) has a severe negative effect on surrounding watersheds. Yet, currently no methods or procedures have been developed to capture the chloride. The situation is particularly dire where highways cross small receiving streams that are the habitat of endangered and threatened species, such as the Topeka Shiner, because the high concentration of chloride in the highway runoff does not dilute sufficiently to prevent toxicity in the hatching and juvenal rearing areas of the streams. This project developed in-ditch salt capture techniques based on mitigation of chloride migration through absorption and capture in a manufactured backfill media. Chloride mass in drainage water was observed and monitored at a range of concentrations before and after percolation through granular soil mixtures “manufactured” to capture chloride and deployed in flow-through sandbags. Absorbance of chloride was quantified by manufactured soil sandbags in ditch-deployed configurations, allowing optimization of the deployed geometry. Field test installation approaches were designed and tested for chloride capture from actual winter maintenance operations.
• Format:
  PDF
• Funding:
  (c)1052639
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:60a91c03ab270c45e08d6d7ec8cd3e67408935f2185afa3906401262e9302b78addb7afd6e07915ad05d5b330534d3771037f54229ffa8aef943aebba524fc14
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/92367/dot_92367_DS1.pdf
• File Type:
  [PDF - 18.11 MB ]