Wildflowers and the Sons of Norway Hall frame the water in Hammer Slough in July 2022. (Joe Viechnicki/KFSK)

Blue clay from a landslide near Petersburg’s public works yard has colored Hammer Slough and Middle Harbor this month.

The slide happened over the weekend of June 25th and 26th . Since then area residents have been reporting that the waters of Hammer Slough appear silted up.

The borough’s public works director Chris Cotta said by email that blue clay from that slide is to blame. It dropped into the waterway upstream and on a different branch of the creek than the one where a local contractor is digging out and replacing a stream culvert. Cotta said the slide blocked the south arm of that creek for a few days. The borough has notified the Alaska Department of Fish and Game and U.S. Army Corps of Engineers, which have permitted the project. Crews have stabilized the slide and are working to remove the rest of the blue clay from the creek bed. However, Cotta said that work is releasing that clay into the water and turning the slough and harbor a chalky gray color.

Meanwhile the state permit for replacing the culvert only allows in-stream work until July 25th. That’s to protect salmon spawning in the creek later in the summer. Cotta said the contractor is making good progress and think they’ll be done with that portion of the work in time.