Tag: dam safety
  • October

    Big Sandy Lake Dam Rehabilitation Project

    Sandy Lake Dam has undergone a series of modifications, repairs and periodic inspections over its 125-year history. From 2011 to 2016, a series of above and below water inspections identified several features that had deteriorated to a point that repair or replacement were necessary to maintain the long-term stability of the structure.
  • February

    Mississippi River Lock and Dam 1, Ambursen Dam Downstream Repair

    The purpose of this project is to re-establish armor downstream of the concrete apron and prevent further scour. Lock and Dam 1 is located on the Minneapolis, Minnesota side of the Mississippi River.
  • March

    Pokegama Dam Slurry Trench Project, Grand Rapids, Minn.

    Pokegama Dam was constructed in 1884. The main embankment was constructed with a pervious, rock and clay-filled timber structure core and covered with sandy material. In 1941, a sheetpile wall was installed upstream of the timber core to minimize unwanted seepage (flow) through the embankment. The existing sheetpile wall has been effective at controlling seepage, but its overall condition is currently in question. Without an effective seepage barrier, the water levels could rise throughout the embankment causing downstream slope instability, which would threaten the integrity of the dam.