With small slide below Interlaken, soggy March brings landslide concerns

An unbelievably soggy March has neighbors in the sloping areas on the north of Capitol Hill worried about landslides.

A small slide closed 14th Ave E between Boyer and Lynn to through traffic Saturday morning. With continuing rains, you can expect to see more mud.

March has already reached its average rainfall totals following weeks of even wetter than usual weather around Seattle.

CHS has reported on small slides over the years and concerns about the slopes of northern Capitol Hill and around Interlaken Park. Our nature writer documented the landslide risk of the area in 2014 including the Hill’s geologic past of glacial till and water-pooling clay:

Then we come in. The grade is altered, creating new faults. Hills are denuded of trees, which hold slopes and mitigate flooding. Barriers to natural water flow diverts it toward unforeseen consequences. People understandably want views and build on cliffs, changing the loads on hills. Generally things more even more unstable. West Capitol Hill, Interlaken, North Capitol Hill. Slides every decade going back in our modern record. I won’t tally the slides in Hill history — that would take too long.

For the most part, recent slides have been mostly limited in damage. In 2011, cracks from the sliding hillside forced an indefinite closure of Interlaken Drive. It reopened after repairs five months later.