Pisces Pleasers
Conservation of fish populations links
environmental projects in Washington and Illinois
By Leslie Lichtenberg
On the surface, there are few similarities
between an Illinois ship canal and a Washington creek,
but the species swimming in both water sources are
connected by similar conservation efforts, which both
resulted in the application of precast concrete.
The
management of fish
Since the early 1990s, the Washington State Department
of Transportation (WSDOT) has managed a fish barrier
removal program designed to inventory and rectify
highway culverts that block fish passage. Fish barrier
removal in Washington state in particular is driven
by the need to provide salmon and other fish with
freshwater access so they can spawn. Barriers to the
natural habitat impede this spawning process and inhibit
salmon recovery. High water velocity, inadequate water
depth and large culvert outfall drops are just a few
of the more common factors in old culverts that create
fish barriers. The aging culvert at Jim Creek in Joyce,
Wash., was originally installed to allow for water
flow, but without consideration of fish passage.
“The
objective is to enhance the salmon population by relieving
old fish barriers,” said Ted Reynolds of Utility
Vault Co., Auburn, Wash., the precast concrete manufacturer
for the Jim Creek project. “The original culvert,
in this case a steel-plated arched pipe, was probably
considered standard 30 years ago.”
Under a cooperative program with the Washington State
Department of Fish and Wildlife (WDFW), the fish barrier
removal initiative has identified more than 600 existing
barriers for correction. WSDOT culvert barriers are
corrected or modified under several scenarios –
in conjunction with highway projects, as stand-alone
projects, during routine maintenance or through a
special retrofit program. Through the efforts of the
fish passage program, more than 220 miles once blocked
by barrier culverts have been reclaimed, according
to WSDOT reports.
“Once
these problem culverts are corrected, the benefits
to fish habitat are real and immediate – in
many cases, fish have been observed upstream of improved
culverts within weeks of restoring access,”
according to the WSDOT Environmental Services Web
site.
The priority fish culvert replacement project at Jim
Creek, which temporarily closed State Route 112 west
of Port Angeles, began construction in September 2003
with the excavation of a 1,000-foot-wide construction
area, including a 25-foot-deep roadway.
“One
of the biggest challenges with this project was that
the excavation was so deep, approximately 35 feet
from the road surface,” said Sean Coleman of
the Port Angeles-based Bruch & Bruch Construction
Inc., contractors for the project. “We had to
build a 30-foot retaining wall about five feet from
the edge of the culvert and then run the wall 65 feet
along the culvert in order to bring in a crane pad,”
he said.
The three-sided precast concrete replacement culvert,
measuring 10 feet high, 28 feet wide and 144 feet
long, was transported and placed using a 500-ton crane.
Forty-three sections were used to build the culvert.
From
start of excavation through the reopening of SR 112
the culvert installation took about 35 days, but it
was not without its share of trials.
“We had a very limited window of time, since
WSDOT would not allow us to close the road until after
Labor Day,” Coleman said. “This was compounded
by the fact that due to spawning cycles, we knew we
had to be out of the stream by the end of September.
Having precast concrete pieces sped up the placement
process considerably.”
Although less than a quarter mile of road was affected,
the six-week closure of SR 112 in the Jim Creek vicinity
was a potential downside of the project.
“We were able to close the road with this particular
project, but a convenient detour is not always possible,
so time was of the essence,” Reynolds said.
Another potential obstacle included pumping of the
creek, which required the use of six different pumps
from various locations. During the initial stages
of the project, the creek was pumped 24 hours a day
for approximately 18 days. Still, these issues, coupled
with heavy rainfall in September 2004, did not deter
WSDOT from replacing the culvert and completing the
project in mid-October during the creek’s low-flow
period. Those involved in the $870,000 undertaking
agree that manpower and the use of precast concrete
enabled the project to be completed on time and within
budget.
“Our crews were out there working 12- to 14-hour
days, six days a week,” Coleman said.
In terms of time and cost savings, there was not a
competitive alternative to precast concrete.
“The alternative would have been to build a
standard bridge, which would have required abutments,
girders and things of that nature – all of which
would have to be cast in place,” Reynolds said.
“Given the constraints and challenges of this
project, precast contributed tremendously with respect
to ease of installation and reduction in time and
labor.”
More than 1,700 miles from Washington state, Illinois
is home to the famous Chicago Sanitary and Ship Canal
(San-Ship), one of the busiest waterways in the nation.
Built in 1910 as an expansion to the Illinois-Michigan
canal, the San-Ship was a vital link in helping to
build the Midwest. Connecting the south branch of
the Chicago River to the Des Plaines River, the present-day
San-Ship runs about 165 feet wide and 25 feet deep.
This man-made channel, originally constructed to reverse
the flow of the Chicago River – long ago a site
for sewage dumping – has evolved today into
a two-way conduit through which a growing range of
exotic species migrates between the rivers and the
Great Lakes. These species, which are not indigenous
to the area, compete with or prey upon native species
of plants, fish and wildlife. Many carry diseases
or parasites that could potentially disturb the aquatic
environment and economy of nearby areas.
Zebra mussels, responsible for recent die-offs among
Great Lakes waterfowl, and Asian Carp, many weighing
upwards of 100 pounds, along with the Grass Carp,
African Water Flea and Round Goby, are just some of
the invasive species that are using the San-Ship to
migrate to other bodies of water, according to a 2001
article in Wisconsin Natural Resources magazine. With
this in mind, the U.S. Army Corps of Engineers, under
the auspices of the National Invasive Species Act
(1996), launched a demonstration project to limit
the spread of aquatic invasive species via the San-Ship
Canal. Working with the Illinois Department of Natural
Resources, the Corps identified an electrical fish
barrier as the optimal tool for effectively reversing
the invasion of “nuisance species” without
interfering with regular canal traffic.
“This array is by far the largest and most unique
electrical barrier in the world,” said Jeff
Smith of Smith-Root Inc.
Smith-Root, based in Vancouver, Wash., developed the
technology for the barrier, which measures 160 feet
across and 400 feet long. As general contractor and
patent holder of the system, Smith-Root designed and
oversaw the barrier installation, which involved laying
electrodes perpendicular to the flow of water across
the bottom of the canal. Forty precast concrete panels,
each weighing between 6,000 and 10,000 pounds, were
set in the water and notched at the top for the placement
of large 4 x 4 ingots.
“The voltage is distributed evenly throughout
the entire water column, but because the barrier is
graduated, fish coming into it will feel the fringe
effect of the electrical field and ultimately be washed
out by the current,” Smith said.
The duality of the electrical barrier, acting as both
a barricade for the invasive species and a repellent
for the fish, is a key factor in its success.
“In nearly all applications, it is 100 percent
effective,” Smith said, adding that in the case
of the San-Ship, the electrical field is completely
unaffected by canal traffic. At approximately 1 to
2 volts per cubic inch of water, the field is non-lethal
and, because of its 35-foot-depth along the bottom
of the canal, the electrical disturbance does not
upset the natural flow of water.
The 2-foot square precast concrete supports, in varying
lengths between 16 feet 5 inches and 9 feet 8 inches
long, were chosen over cast-in-place because of time
and cost savings. Aurora Concrete Products of Aurora,
Ill., was chosen as the precast manufacturer for the
job.
“The Corps was looking at pouring the concrete
on site, but that would have required bringing in
cranes to pour, strip and set these large support
beams,” said Stephen Fossler, president of Aurora
Concrete Products. “In terms of quality control,
precast was the way to go.”
“We use a lot of precast in our projects because
it saves time and expense,” added Smith. “Using
precast allows us to set the concrete supports directly
in the body of water rather than having to ‘de-water.’”
Building on the success of a demonstration project
in 2001, the second phase of the electrical fish barrier
at the San-Ship Canal is on target for a March 2005
completion date.
In the meantime, government agencies, working with
both public and private stakeholders, will continue
to seek environmental solutions to the problems threatening
the nation’s fish, wildlife and other natural
resources.
“For environmental purposes, commercial fishing
and maintaining balance in the entire ecosystem, you
can’t underestimate the importance of projects
like this,” Fossler said.
The application of precast concrete in environmental
projects nationwide is growing, and precast manufacturers
such as Utility Vault and Aurora Concrete Products
are redefining their services to stretch beyond that
of our nation’s infrastructure, and to help
sustain America’s ecosystems for years to come.
Projects Profile
Projects: Jim Creek Culvert/San-Ship
Electrical Fish Barrier
Project Owners: Washington
State Department of Transportation/Chicago Sanitary
and Ship Canal
Architect: Washington
State DOT/Smith-Root, Vancouver, Wash.
Contractors:
Bruch & Bruch Construction Inc., Port Angeles,
Wash./Smith-Root, Vancouver, Wash.