Tweets:

Fred Bird requested that the following memo about a favorite Puget Lowlands
birding site be posted to Tweeters. As Fred says, it's not good news.

Hal Opperman
Medina, Washington
hal at catharus.net

___________________________________

Significant erosion changing Spencer Island; user input sought as solutions
considered

Visitors to Spencer Island, east of the City of Everett, are accustomed to
seeing barricade tape and flagging on the dike trails that circle the
island. These markers have warned of calving of the exterior wood dike and
erosion around two culverts located in the cross dike. This year, new
warning signs were seen on the property, which is co-owned and managed by
the Snohomish County Department of Parks and Recreation (Parks) and the
Washington State Department of Fish and Wildlife (WDFW). In July, a
significant fire started in the exterior dike at the north end of the island
and necessitated temporary closing that section. The fire burned a large
area and continued to smolder into November. In October, a new sign was
added to the island entrance warning visitors of the collapse of one of the
exterior footbridges and, in November, warning signs were posted due to
concerns about the increased erosion that has been observed on the cross
dike and questions about its stability.

The cause of several of these problems is the wood chip material which makes
up a large component of the dikes. The exterior dike was originally
constructed in the early 1900s as the island was converted to agricultural
use and acted to control tidal fluctuations into the island. In the late
1960s and early 1970s wood material (hog fuel) was readily available, so it
was added along with other miscellaneous material to the existing dike. This
wood chip material is unfortunately susceptible to calving, erosion and
fire.

The other major factor influencing the stability of Spencer Island is tidal
water flows. The diurnal movement of water past the island, as well as
through the exterior and interior culverts, and the previously breached
openings in the dike have caused, and continue to cause, erosion. It is
this action, coupled with the increased water flows that the area has seen
recently that caused the recent foot bridge collapse.

Since acquisition of this property by WDFW and Parks in 1985, the changing
nature of this island has been monitored. Work was conducted in 1994 to
correct areas of dike deterioration that were known at that time, but losses
to the dike trail have continued. In 2001 major erosion in the cross dike
was recorded. And, earlier this year, an Army Corps of Engineers study was
completed to estimate the cost of repairing the known points of erosion.
This estimate came to approximately a half million dollars, not including
the price of permits, mitigation, annual maintenance and a contingency
buffer. This estimate was made prior to the recent fire and bridge
collapse.

At this time, WDFW and Parks are pursuing solutions to address these
problems and maintain public access to the island. Currently, the island is
used by birders, walkers, joggers, hunters, and others. The erosion which
is occurring threatens to remove portions of the trail system and reduce the
capacity for walk-in hunting. The instability of the island however and the
high costs associated with repairing and maintaining the historic recreation
access, necessitate looking at alternative management and access to the
island.

Currently WDFW and Parks are working toward providing controlled breaching
of the exterior and interior dikes. By designing the breaches for the
hydrology of the site, these engineered breaches will be placed in desired
locations and reduce the extent of damage which could occur with natural
breaching. At the current rate of erosion, natural breaching could occur as
early as this season or the next. Breaching of the exterior and cross dike
will have the benefit of opening approximately 250 acres to tidal hydrology
and the important habitat that these acres provide to salmon. Estuarine
habitat is vital for resting, rearing and transition space for salmonid
species traveling between salt and fresh water. This change will cause the
north end of Spencer Island to look very much like the 50 acres at the south
end, which was restored to tidal hydrology in 1994.

Public access to the island will be affected by these changes. At this
point, it is unclear what the complete impact will be, but it is foreseen
that the majority of hunting in the north end may shift to boat usage and
the ability to walk or jog around the entire exterior of the island will no
longer exist. Additionally, funding will need to be obtained to make
repairs to the southern loop in order to restore the route there. This will
involve repairing the collapsed bridge and bridging the breaches that will
be created in the cross dike.

Because public input is important to the long term management of Spencer
Island and how public access is handled after these changes, public meetings
will be scheduled in the upcoming months. Public comment is welcomed in the
meantime and requests to be notified of these meetings may be made to:

Sharon Walker, Senior Park Planner Snohomish County Parks & Recreation 9623
32nd St. SE Everett, WA 98205 425-388-6616 sharon.walker at co.snohomish.wa.us

Curt Young Snoqualmie Wildlife Area Manager Washington Department of Fish &
Wildlife P.O. Box 1756 Duval WA 98019 425-330-7725 youngcpy at dfw.wa.gov