The end game for the new Arboretum multi-use trail announced last week is the second phase North Entry project planned for the post-520-replacement-era. The project would return the WSDOT Peninsula / Miller Street Dump to the Arboretum after it was taken for highway use half a century ago.
Things are different this time around and WSDOT will replace wetlands lost to 520’s expanding footprint with new wetlands at several sites around Lake Washington. One of those sites includes five acres on the garbage-dump-peninsula’s western shore which will be restored and planted with native species to increase biodiversity. Separate from this mitigation work but in partner with it, the proposed North Entry project would incorporate the new wetland, daylight Arboretum Creek (currently piped underground) and extend the park to the future Montlake Lid.
Some 28,000 cubic yards of earth will be regraded to create the new wetland. Rather than hauling the material offsite, the North Entry plan calls for it to be piled into a 40-foot hill at the peninsula’s south end, creating a new overlook with views of the wetland and surrounding tree canopy. While the plan is still in early stages, Seattle Parks expects to reclaim ownership of the peninsula once highway construction is complete. Details of the land transfer are not settled, but it is assumed WSDOT will not keep a property for which it has no use. The Ramp-to-Nowhere made the peninsula “useless” when the R.H. Thomson was defeated in 1971 — those ramps are to be demolished by 2016.