PROBLEM STATEMENT
Lake Leland Integrated Aquatic Plant
Management Plan
In January of 1998 at the second meeting of the Lake Leland steering committee, members
established a list of problems related to invasive aquatic vegetation. Many of these
problems had been previously identified at meetings of the Leland Neighborhood Improvement
Club and at a public meeting in August 1997, which specifically addressed invasive
vegetation in Lake Leland. The identified problems are related to three invasive weeds:
Brazilian elodea (Egeria densa), reed canary grass (Phalaris arundinacea),
and yellow flag iris (Iris pseudacorus). The problems associated with each species
are discussed below.
BRAZILIAN ELODEA
In the summer of 1994 during a routine Department of Ecology
aquatic plant survey of Lake Leland, the presence of Brazilian elodea was first officially
noted. This noxious, non-native, invasive species has been spreading at a steady rate and
is rapidly filling in the shoreline up to a depth of about ten or eleven feet. In the last
four years, Brazilian elodea has become well established in the south end of the lake, and
plants are now found scattered along the perimeter of the rest of the lake (Figure 1). Fishing, boating, and
swimming have been affected due to the density of the plant. Many private docks
have become totally surrounded with this noxious weed, which hampers safe swimming.
Jefferson County Parks and Recreation provides a campground and maintains a swimming
area and boat ramp at the lake. Brazilian elodea has now been found along the shoreline of
the park which could eventually hinder safe swimming in that area. The rapidly spreading
weed could result in less use of the county campground, which is a source of revenue to
Jefferson County Parks and Recreation.
The community feels that their property values could be lowered by the steady
encroachment of the weed. Another concern is that Brazilian elodea could alter the
ecological balance of the lake, affecting fish and wildlife habitat and the excellent warm
water fishery that presently exists at the lake.
A very important concern of the committee is the potential for the spread of Brazilian
elodea to other lakes in the surrounding area. This noxious weed is easily transported to
other locations on boat motors, trailers, and fishing gear and is known to establish new
infestations from plant fragments. There are several lakes in the area that currently are
not infested with Brazilian elodea, one of which is Crocker Lake, located just three miles
north of Lake Leland. Fishermen are known to utilize both lakes in the same day.
A final concern is that the methods chosen to control invasive plants in the lake do
not jeopardize the water quality of the lake. Lake Leland is a source of domestic water
for some residents, and the community is particularly concerned about using broad spread
chemical treatments which might compromise human safety.
REED CANARY GRASS
Reed canary grass, another exotic species listed by the state as a noxious weed, is
also a problem at Lake Leland. This water tolerant grass, introduced into the area to
provide forage for livestock in wet areas, is notorious for growing in stream channels and
causing drainage problems. Canary grass grows densely in the upper 2000 feet of Leland
Creek and is a major factor in causing the flooding problem and high water level in Lake
Leland. Beaver dams on Leland Creek also contribute to the problem.
The steering committee has thoroughly discussed the history of the flooding problem,
which has occurred for a long time. During the late 1940s the Soil Conservation
Service (SCS) assisted local farmers in dredging out the inflow and outflow channels to
the lake. According to long time resident Hector Munn (Munn 1986), the lake level dropped
dramatically for several seasons, enough so that docks had to be extended to reach the
water level. One could walk through the culvert under Leland Valley Road West. The road is
now flooded most of the winter and spring, and the culvert is full all summer long.
However, the dredging was only a temporary fix. In April of 1988, the SCS again addressed
the drainage problem and provided an analysis (Appendix A). The SCS had no solutions to
recommend due to environmental factors, permit systems, and federal and state regulations
regarding wetlands. Recurrent flooding over Highway 101 north of the lake prompted the
Department of Transportation to look for a solution to the rising water table in late
1990. The Jefferson County Conservation District served as lead agency and identified
removal of canary grass, a beaver dam, and natural obstructions as a first step in the
solution. In the fall of 1991, a Leland Creek channel restoration project utilizing an
excavator and a "Cookie Cutter" (a flat bottomed boat used to cut vegetation in
lakes) cleared canary grass from the 2000 foot section of Leland Creek below Lake Leland
and, as a result, the lake flowed steadily through the outlet. The lake water level
dropped dramatically for a few years but has since returned to previous levels (see Figure 12 in Watershed
Characteristics). Flooding was only temporarily reduced, because problems of funding,
responsibility, and permitting plagued the project and prevented continued maintenance to
ensure that the outlet remained open.
Seven years later the issue has not resolved itself. The outlet channel is again
virtually clogged with canary grass and the flooding problem has been increasing. Over the
past three years the lake level has continued to rise. The higher water table has
contributed to flooded roads (county and state) and septic drainfields. The latter could
result in the release of nutrients and fecal coliform bacteria to the lake. To date, two
homes have been flooded and others are at risk. Several properties are in jeopardy and
useable farm lands have decreased. Dead trees resulting from a high water table can be
seen around the shoreline. Since it has been demonstrated that improved drainage reduces
the lake water level, neighbors regularly patrol Leland Creek for obstructing beaver dams.
And they continue to look for feasible solutions to control the canary grass.
It should be noted that the Washington Natural Heritage Information System database
lists the presence of bristly sedge (Carex comosa), a state sensitive plant
species, in the wetland at the south end of the lake and along Leland Creek. Although the
Natural Heritage Program has no regulatory authority, the Leland community wishes to
respect the uniqueness of the Leland ecosystem and will plan any canary grass controls
with respect to this information.
YELLOW FLAG IRIS
Yellow flag iris, a non-native invasive species not listed on the state noxious weed
list, has been spreading in some areas of the lake shoreline. The density of the iris
along the shore crowds out native vegetation and can impede human or wildlife passage.
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Contact Kathy Hamel by e-mail at kham461@ecy.wa.gov
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