Twins Nearshore Overview
The Twin’s nearshore drift cell includes approximately four linear miles of rocky and sandy shoreline. The shoreline is highly erosional. Parks (2005) concluded that there is no long-term net apparent sediment transport direction, but rather a high degree of inter-annual variability between east/west/ and north offshore across the shore platform, and that sediment transport may be impacted by shoreline modifications. The shoreline of the Twins nearshore is a mixture of private and state ownership. A significant portion of the Twins shoreline is owned and managed by Lafarge.
Todd et al. 2006 describes the Twins nearshore as a moderately impaired stream delta complex. The mole is the feature that is impairing the shoreline by disrupting sediment transport along the shoreline and disconnecting upland sediment sources from the shoreline. Once removed the ecosystem forming processes of the region will be largely restored.
The project removed the armoring around the perimeter of a 5.6 acre earthen filled pier (also called a ‘mole’) to allow natural processes to restore over 14 acres of nearshore habitat. Approximately 30,000 cubic yards of riprap (non-native rock armor) concrete and sheet pile were removed. Removing these armoring features is allowing clean native sediment that makes up the fill of the mole to naturally erode and replenish the local shoreline. After fourteen years of planning and funding pursuit, armor removal began 24 July 2017 and concluded 31 August 2017. Rock armor removed from tidelands is stored on the upland portion of the Lafarge owned property.