Bank erosion putting community water wells and transmission line in danger

Observation by Paul Walton:

As the rains linger though out July, the Noatak River rose and gouged its own river channels and paths of of eroding banks that affected the Noatak water supply. 2 wells and the transmission line on some parts of the island where the wells are located, eroding bank loss of over 50 feet in some part of the rivers bank.

Comments by LEO Editors:

Following two extremely warm and dry summers, (in 2020 Kotzebue had the driest summer since 1977), the summer of 2021 has been quite the turn around with cool temperatures and plenty of rain. Consequently, the major driver for erosion has not been heat, but rather flooding. LEO Network has received a series of erosion-related posts from Noatak since June 26th, with detailed observations and measurements provided by Water Operator Paul Walton and Tribal Environmental Coordinator Jeffrey Luther. These observations are attached. By way of example, a cumulative of 18 feet of river bank was lost adjacent to the airfield by July 16th, and 28 feet adjacent to the old landfill. Critical infrastructure that is threated be bank erosion includes the airport and airport road. The water transmission line and wells which are the subject of this post, are located off the bank on a small island in the Noatak River drainage. Even more exposed to the kinds of flood events which have occurred this summer. Mike Brubaker

Rick Thoman with ACCAP writes:

Following an unusually wet June, the Noatak River basin saw excessive rain again in July, resulting in the sustained high river levels and accelerated bank erosion. The automated weather station near the confluence of the Kelly and Noatak Rivers received more than six inches of rain in July, following five inches of rain in June. This is more than three times normal. The upper Noatak Basin received about twice the normal rainfall in June. Red Dog Mine received over a total of 14" of rain in June and July. The persistent rains were the result of a stable weather pattern, with warm high pressure anchored over Siberia and western Canada, and in between unusually persistent low pressure over the northern Bering and southern Chukchi Seas.

Chris Dankmeyer, Environmental Health Manager at Maniilaq Association writes:

Water levels in the Noatak River have been high this year and this has translated into increased/rapid erosion along the river. As many of you are aware, drinking water infrastructure in Noatak is on an island and erosion is threatening the transmission line. Attached are some photos and diagrams that Paul Walton, Water Plant Operator, wanted me to pass along. This indicates how close the erosion has gotten to the well transmission lines there. A little historical context, erosion and the river have completely claimed 2 older wells and transmission line that would be in the river channel at the bottom of the photos (i.e. old infrastructure was literally swept away). There’s concern about how much longer the infrastructure will last if not protected and/or relocated to a more protected location. What would be the proper course to address this issue? Is this an SDS need to capture that could get fixed 3 years from now, or are there quicker opportunities to evaluate, protect or relocate this infrastructure?

Max Neale with the Center for Environmentally Threatened Communities writes:

ANTHC supported Noatak to secure funding for a riverine erosion assessment and select a consultant to complete the work. The project is in progress. It is my understanding that Bristol Engineering and Golder Associates will be visiting Noatak early next month. I’ll make sure that their field investigation looks at this issue specifically to estimate the time to damage and share an opinion on protecting that portion of the island. We can consider a team discussion following on the results of their visit. There are likely faster ways to address this than the Sanitation Deficiency System (SDS), depending on the time to damage. Paul and Jeff - do you have an estimate for when the transmission line will be impacted by erosion based on the recent rate?