of Three Digesters and a Mixing 1
'or the Brightwater Treatment System
Project Highlights
LOCATION AND BUILDING SPECS:
A 36-million-gallons-per-day regional waste treatment facility,
located on a 114-acre site in Woodinville, Washington.
DESIGN:
Facility architects, engineers, and contractors incorporated
a variety of sustainable design and building practices. The
site includes a salmon habitat, a reforestation area, and an
environmental education and community center.
MATERIALS REUSED OR RECYCLED:
The Brightwater Team used 13,800 tons of fly ash as a
cement substitute, reused and recycled construction and
demolition (C&D) materials, reused 200 trees and root
wads for salmon habitat, recycled 15,000 cubic yards
of compost material, and used recycled materials in the
environmental education and community center.
IMPACT:
To date, the Brightwater Team has diverted 67% of all C&D
materials, reused more than 370,000 tons of material
in construction, and saved more than $500,000 from
the reuse and recycling of materials. Environmental benefits
include reducing 12,723 metric tons of C02 emissions
from the recycling and reuse of fly ash and concrete and
eliminating approximately 925,000 vehicle miles through
the reuse of excavated soils onsite.
Brightwater
Wastewater
Treatment System
Built with the Environment in Mind
To meet the growing service demands of the Puget Sound
region over several decades, King County, Washington, is
building one of the most sustainable wastewater treatment
systems in the country. This 1.8 billion dollar project, with
its conveyance outfall partly funded through the Clean
Water Act State Revolving Fund, is King County's largest
clean-water capital project in 40 years, and incorporates
sustainable design and building practices in all facets of its
construction and future operations.
Brightwater will treat on average about 36 million gallons
of wastewater per day, using membrane bioreactor
technology. Thirteen miles of pipes and pumps stretch
underground, taking wastewater to and from the plant,
with a marine outfall more than a mile long and 600 feet
deep. The Brightwater Team will build a 15,000 square
foot environmental education and community center with
sustainable design elements on their 114 acre site, which
also includes approximately 70 acres of public open space.
Construction is expected to be completed in 2011.
From the beginning, the Brightwater Team made a commitment
to sustainability. The architects, engineers, and contractors
working on the project have been dedicated to protecting
natural resources, limiting the impacts of construction, and
leading the way in the development of sustainable practices.
Brightwater used four key sustainable practices including:
• Using Coal Fly Ash in Concrete as a Cement Substitute
• Retaining Excavated Soils Onsite to Visually Screen
Wastewater Processing Areas
• Reusing Materials to Create Salmon Habitat &
Reforestation Area
• Building Green Onsite Environmental Education &
Community Center
U.S. ENVIRONMENTAL PROTECTION AGENCY
CONSTRUCTION INITIATIVE CASE STUDY
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Sustainable Practices: From Start to Finish
Using Coal Fly Ash in Concrete as a
Cement Substitute. Concrete containing
coal fly ash was used in the treatment facility,
portal, and deep tunnel conveyance. The
concrete mix utilizes 120 pounds per cubic
yard of fly ash in lieu of cement. Since the
start of the treatment plant construction,
13,400 tons of fly ash has been recycled by
using it as a cement substitute. Similarly, in
2008, 400 tons of fly ash was used in the
conveyance tunnel construction. Recycling
these 13,800 tons of fly ash results in a
12,543 metric tons C02 emission reduction1,
which is equivalent to the annual greenhouse
gas emissions from 2,297 passenger vehicles.2
Construction workers pour concrete containing fly ash
Retaining Excavated Soils Onsite
to Visually Screen Wastewater
Processing Areas. The construction team
used excavated soil to create landforms and
buffers-attractively screening processing
areas from public view. By eliminating the
need to haul excavated material offsite,
the number of truck trips to and from the
site was significantly reduced. Bnghtwater
estimates that this saved 37,000 truck trips
of 25 miles each-eliminating approximately
925,000 vehicle miles.
Creating a Salmon Habitat &
Reforestation Area. The northern 43 acres
of Bnghtwater have been redeveloped as a
restored and enhanced salmon habitat and
reforestation area.
1 Estimated using EPA's Waste Reduction Model (WARM)
(updated August 2008), http://www.epa.gov/warm
2 Estimated using EPA's Greenhouse Gas Equivalencies
Calculator (updated February 2009), http://www.epa.
gov/cleanrgy/energy-resources/calculator.html
Cost Savings and Benefits
Reused trees and mot wads in the salmon habitat
Features include:
• Beused more than 200 trees and root wads
(cost savings: $20,000);
• Planted over 22,000 native plants including
5,000 seedlings;
• Recycled approximately 15,000 cubic
yards of compost material (cost savings:
$450,000);
• Restored approximately 1,350 feet of
stream corridor and added 350 feet of new
stream corridor;
• Created 29,000 square feet of pond habitat;
• Constructed 4 acres of enhanced emergent
and forested wetland habitat; and
• Provided infiltration for stormwater runoff
during construction in the established forest.
Building On-Site Environmental
Education & Community Center. The
Center is in the process of pursuing Gold level
certification or higher through the U.S. Green
Building Council's Leadership in Energy and
Environmental Design (LEEDI® standard.
Sustainable building design elements include:
• Incorporating natural ventilation and
daylighting
• Installing energy efficient lighting and
ENERGY STAR® appliances
• Utilizing temperature controls and radiant
floor heating from waste treatment plant
energy
• Purchasing low-flow toilets that use
reclaimed water from the treatment plant
• Using reclaimed water for irrigation
• Building a green roof
• Educating the public about the green
building elements
Overall, the Bnghtwater Team has achieved a 67% diversion rate of all construction and demolition
materials to date. The Brightwater Team consistently looks for opportunities to first reuse materials
onsite and then recycle where reuse is not possible. In all, more than 370,000 tons of materials
have been reused in construction. Of this, 3,900 tons alone were concrete, and its reuse saved the
project approximately $39,000. The concrete reuse also resulted in 180 metric tons C02 emission
reduction,1 which is equivalent to the annual greenhouse gas emissions from 33 passenger vehicles.2
The reuse of landscaping debris and onsite compost material saved $470,000. In addition, using
13,800 tons of fly ash as a cement substitute resulted in a 12,543 metric tons C02 emission
reduction, which is equivalent to the annual greenhouse gas emissions from 2,297 passenger
vehicles. Additional cost savings and environmental benefits from the reuse and recycling of
industrial materials are expected throughout the construction of this vital project.
Contact info
Melissa Winters,
O.S. EPA, Region 10
winters, melissailepa.gov
Michael Popiwny,
Architectural Design and Mitigation Manager
King County Department of Natural Resources and Parks,
Wastewater Treatment Division
michael.popiwnyilkingcounty.gov
CONSTRUCTION INITIATIVE CASE STUDY
EPA PUBLICATION NUMBER: EPA530-F-09-005, AUGUST 2009
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