Summer Internship 2007
Water Management Strategies: A case study based exploration of local projects
Matt Martenson, Intern in collaboration with
Jonathan Morley & Rachael Meyer
The Berger Partnership PS Landscape Architecture 1721 8th Avenue N Seattle, WA 98109 v 206.325.6877 fa206.323.6867 bergerpartnership.com
A case study based exploration of local projects
Matt Martenson in collaboration with
Jonathan Morley Rachael Meyer
2007
Contents Green Roofs
Green Roof System Comparison Bertschi School Point Defiance Zoo & Aquarium - Animal Healthcare Facility Ballard Public Library Kitsap County Administration Building Woodland Park Zoo - Zoomazium The Berger Partnership Project List
Cisterns
Components of Rainwater Harvesting Carkeek Park - Environmental Learning Center Cascade People’s Center Merrill Hall The Berger Partnership Project List
Stormwater Planter Denny Park Apartments
Living Machine Islandwood
Summer Internship 2007
Water Management Strategies:
design considerations: structural loading, exposure
re tu uc str
i dra
r rie
O
H2
e tur uc r t s
12 40 lifespan yrs
$low cost|$high cost per SF
le
ti tex
o ge
ge ina a r d
al
i ter ma
r rie
ba r
ge na
al
i ter ma
dia
me
g win gro
100
g
ba r
lifespan yrs
10 40 $low cost|$high cost per SF
70
le
ti tex eo
Intensive green roof >10”
Semi-Intensive green roof 6-10”
30
O
H2
dia
me
O
H2
ree ttuur ruucc t r t s s
graphics by The Berger Partnership
tions, stormwater management capacity reduced: heating and cooling costs, heat island effect
benefits: increased: biodiversity op-
tions, stormwater management capacity reduced: heating and cooling costs, heat island effect
benefits: increased: pedestrian access, biodiversity options, stormwater management capacity reduced: heating and cooling costs, heat island effect
design considerations: structural
design considerations: structural
design considerations: pedestrian
benefits: increased: biodiversity op-
loading, high impact from predatory birds, exposure, structural loading, irrigation may be necessary
loading, reduced impact from predatory birds, exposure, structural loading, irrigation may be necessary
safety, structural loading, plant maintenance, shading from plants, comparatively high irrigation demand
typical non-green roof . thin-extensive green roof . extensive green roof . semi-intensive green roof . extensive green roof
benefits: increased: biodiversity options, stormwater management capacity reduced: heating and cooling costs, heat island effect, no irrigation required
n
tio ula ins rier
%mitigated stormwater|%runoff
re tu uc r t s
ge ina dra
al
i ter ma
ba r
O
H2
$low cost|$high cost per SF
5 10 lifespan yrs 40
n tio ula r rie
ins
ge
95
n o ti n te re w a te
r m
ins
benefits: inexpensive
Extensive green roof 3-6”
75
$low cost|$high cost per SF
7 lifespan yrs 40
25
ge ina dra
al
ri ate
le
xti ote
g win gro
%mitigated stormwater
n
tio ula
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g win gro
SYSTEM COMPARISON: Green Roofs
$20
22 20 re tu uc r t s
le
xti ote
%mitigated stormwater|%runoff
O
H2
t ma
ba r
ba r
r rie
%mitigated stormwater|%runoff
lifespan yrs
3 20
Thin-Extensive green roof <3”
9
12
80 20 %mitigated stormwater|%runoff
$low cost|$high cost per SF
Typical non-green roof
f
roo
um
d se
green roof | cistern
Attributes:
designer(s)/builder(s): Miller Hull P a r t ngrowing e r s h i media p (Arch.), Weisman Design Group (L.Arch.) c o m pfilter leted: 2007 s i z e : drainage 4 8 0 spanel q/ft c o s t :H2$O 8membrane .00 sq/ft for materials, $2.00 s q / f t insulation installation cost and shipping c o s t Hw2Oe sensor re waived type: extensive green roof exposure/slope/aspect: partially shaded, nearly flat plants: sedum mix irrigation: temporary soaker hose has been used occasionally g r o w i n g m e d i a : Xero Flor sedum mat p r o d u c t s / l a y e r s : Xero Flor 301 System maintenance: none (to date, 8/20/07) features: the green roof runoff is directed to a cistern system, this Xero Flor system is laid directly onto the corrugated metal roof, with no root protection layer or waterproof membrane
corrugated metal roof
gutter
1"
en
roo
fa
nd
water retention fleece drainage layer corrugated steel roof
cis
ter n
sys
tem
Lessons Learned: ( 1 ) The gutter for the green roof is set away from the green roof. This results in at least 50% of the water being lost as indicated in the drainage issue diagram above. Extra care should be taken to ensure that
mechanical filter and cistern
green roof / cistern drainage systems are adequately connected. ( 2 ) This green roof is in a highly visible location at a school which has a stated commitment to sustainable practices, yet it is not accessible. Bertschi school has provided an accessible sample Xero Flor system located at ground level where it can be used as a tool to teach students about green roofs. ( 3 ) This green roof covers an otherwise uninsulated walkway. Choosing to place a green roof in an uninsulated environment negates the insulation benefits that green roofs can provide. ( 4 ) Using waterproof/resistant materials such as corrugated metal can eliminate the need to have waterproof membranes and root barriers. This results in a simplified green roof. solar panels, green roof, walkway
2227 10th Avenue East . Seattle, WA 98102
roof profile and drain
CASE STUDY: Bertschi School
drainage issue diagram
gre growing media
Xero flor sedum mat teaching tool
green roof
plants: approximately 6 of the following
roof surface view
species: Allium schoenprasm, Delopserma n u b i g e u m , D. c o o p e r i i , E c h e v e r i a s p . , Petrohagia saxifrage, Sedum floriferum, S. album, S. sexangulare, S. spurium ‘Roseum’, S. pinofolium, S. reflexum, S. sarmentosum, S. boehmii, Sempervivum sp.,
irrigation: hand watering growing media: 2.5-3” products/layers: Sarnafil: System
1000
west facing roof
3"
maintenance: no weeding, seasonal handwatering, sedum have been cut and spread features: a sensor system installed beneath the waterproof membrane can detect leaks, 1000 gal. cistern n o t e s : c a c t i w e r e p l a n t e d o v e r 1 y r. ago, this green roof required no additional structural work on the building observations: Sedum sp. are the most successful. Cacti are doing well.
Lessons Learned: (1) This green roof has attracted much interest. There is no permanent access
south facing roof
growing media filter fabric drainage panel H2O membrane insulation H2O sensor
profile
to the roof. Access to green roofs for educational purposes should be considered. (2) Sedum album and Sedum sexangulare have per-
dominant sp. - Sedum album
formed best. Roof aspect seems to have an effect upon plant performance. The roof that is facing west has shown the best plant performance. (3) The facilities manager, Stan, felt that a more permanent irrigation system would have been useful. (4) A 1000 gal. cistern holds runoff from the roof, but this cistern is not connected to any system for use. The water from the cistern could be used to irrigate the green roofs. (5) The soils have shown some subsidence or loss to erosion. This should be expected in green roof systems. (6) These roofs have relatively few weeds, which may be a result of the thin, dry growing media. dominant sp. - Sedum sexangulare
P o i n t D e f i a n c e Z o o . 5 4 0 0 N . P e a r l S t r e e t . Ta c o m a , W A 9 8 4 0 7
d e s i g n e r ( s ) / b u i l d e r ( s ) : B o x w o o d A rc h i t e c t s , Te u f e l N u r s e r y, S i k a S a r n a f i l (green roof company) completed: 2002 size: 3,500 sq/ft cost: $10 sq/ft type: extensive green roof exposure/slope/aspect: full sun, 10º15º slopes, north facing, south facing, and west facing (3 roofs).
CASE STUDY: Animal Healthcare Facility
Attributes:
green roof
Attributes:
designer(s)/builder(s): Bohlin Cy-
winski Jackson (Arch.), Swift & Co. (L.Arch.), Rana Habitat & Restoration (Green Roof Consultant) completed: 2005 size: 20,500 sq/ft cost: $20 sq/ft type: extensive green roof exposure/slope/aspect: full sun, concave parabolic, south to north
plants: Achillea tomentosa, Armeria
roof profile
growing media filter fabric drainage panel insulation root barrier H2O membrane
plants - 2005
plants - 2007
( 1 ) It was believed that irrigating only the the north (south facing) portion of the roof would be sufficient and that water would move through the roof
skylight and monitoring equipment
by capillary action and gravity. The roof requires hand watering in addition to this system. ( 2 ) Upon completion, the roof featured 13 species. Of the original 13, the remaining visible species composition is mainly clumping grasses. Relying upon minimal irrigation and clumping grasses to provide the recommended 100% vegetal cover may not be sufficient. ( 3 ) 1/3 of the plants on the roof are Festuca idahoensis which has a deep fine root system and has not performed well in the 5” soil profile. Plants should be chosen to match the soil profile and climatic conditions of the roof. ( 4 ) The biodegradable coconut fiber, which was installed to prevent erosion, has presented a persistent obstacle to weeding and replanting. skylights and monitoring equipment
5614 22nd Ave NW . Seattle, WA 98107
Lessons Learned:
main entrance
5”
were Festuca idahoensis, these plants have deep fine root systems. irrigation: drip/pop-up irrigation at n o r t h ( s o u t h f a c i n g ) e n d o n l y, s u p p l e mented with hand watering, in summer 2007 irrigation was added to the south portion of the roof growing media: 4”, 45% mineral component, 15% sand, 40% organics products/layers: American Hydrotech: M o n o l i t h i c M e m b r a n e 6 1 2 5 ® - E V, H y droflex® RB, Styrofoam® Insulation, L i t e To p ® E n g i n e e r e d S o i l , c o c o n u t fiber mat to prevent erosion maintenance: average of 5 hours per week as of 2007 features: periscope that can be used to view the roof, viewing room(not public), solar panels, skylights
CASE STUDY: Ballard Public Libary
viewing room and roof access
maritime, Carex inops, Eriphyllum lanatum, Festuca rubra, Festuca idahoensis, Phlox subulata, Saxifrage cepitosa, Sedum oreganum, Sedum album, Sedum spurium, S i s y r i n c h i u m , T h y m u s s e r p h y l l u m , Tr i t e l e i a hyacintha. 5,400 plants out of 18,450
p l a n t s : Fragaria chiloensis, Arctostaphylos uva-ursi, Lavandula angustifolia, Lychnis coronaria, Malva sylvestris, Euphorbia sp., Sedum spathufolium, Clarkia sp., Sisyrichum sp., Sidalcea, Gilia sp., Penstemon Sp., Lasthenia sp. Festuca ovina, Carex sp.
green roof weeds
6â&#x20AC;?
i r r i g a t i o n : d r i p i r r i g a t i o n f o r 2 - 3 y r. establishment period g r o w i n g m e d i a : 6 â&#x20AC;? p r o p r i e t a r y s o i l m i x view from green roof deck facing northwest products/layers: American Hydrotech maintenance: unknown features: Conventional and green roof runoff is captured in cisterns and used for irrigation. Overflow from the cisterns is directed through the landscape t o a r a i n g a r d e n ( r e f e r t o c i s t e r n d i a g r a m ). T h e growing media water captured in the cisterns will lower demand on municipal supplies by 270,000 gallons or about 50% filter fabric of the irrigation need. After the landscape is estabdrainage panel insulation lished, the cisterns will satisy 100% of the irrigation root stopper need. The cisterns function as part of the foundation H O membrane of the building which helped to integrating costs and reduce the budget. Each of the 4 green roofs feature an accessible deck. 2
Lessons Learned:
cistern diagram
(graphic courtesy of SvR Design Company)
green roof edge condition
( 1 ) The cisterns were sized to the amount of water the landscape would need once established. Sizing cisterns based upon future water needs means that the cisterns will not be too large or too small. ( 2 ) The cisterns were integrated into the building structure. This resulted in lower costs as compared to cisterns which are separate from structures. ( 3 ) Coordinating green roofs with small decks results in spacious, open, outdoor space above ground level. Access to the green roof also contributes to educational opportunities. ( 4 ) This roof had a significant quantity of weeds, this may be due to the thick growing profile which is capable of supporting greater diversity than a thin roof. cistern overflow and conveyance system
619 Division Street . Port Orchard, WA 98366
green roof deck
green roof|cistern
designer(s)/builder(s): SvR Design C o m p a n y ( C i v i l E n g . ) , S i t e Wo r kshop (L .Arch.), Miller Hull Partnership (Arch.) completed: 2005 size: 11,500 sq/ft green roof, 225,000 gal. cistern capacity cost: The cisterns & green roofs added 10-15% to the cost of the project. The added cost is offset by money saved on irrigation type: extensive green roof exposure/slope/aspect: partial sun/ shade, nearly flat, north
CASE STUDY: Kitsap Co. Admin. Bldg.
Attributes:
green roof
Attributes:
designer(s)/builder(s): Mithun(Arch.) completed: 2005 size: 8,000 sq/ft cost: $30 sq/ft type: extensive green roof exposure/slope/aspect: full sun, convex parabolic, south to north
plants:
Gaultheria shallon, Polystichum munitum, Arctostaphylos uva-ursi, Allium cernuum, Sisyrinchium douglasii, Lupinus polyphyllus, Fragaria chiloensis.
1000 plants were replanted 1.5 years after planting due to failure and bird predation. Allium cernuum, Fragaria chiloensis and Arctostaphylos uva-ursi are performing best, Lupinus sp. seeded all over and had varying success
Lupinus sp.
image courtesy of M. Martin
Lupinus sp.
image courtesy of M. Martin
roof profile
( 1 ) The roof is planted with PNW natives. These plants perform similarly to native plants, except they go into summer dormancy a couple weeks earlier
6”
Lessons Learned: growing media drainage panel insulation root barrier H2O membrane
irrigation system
image courtesy of M. Martin
coconut mesh image courtesy of M. Martin
(D. Selk 2007). ( 2 ) The self-seeding Lupinus sp. has been successful at colonizing the roof and has not required replanting. Self seeding/replicating species may be well suited to providing 100% vegetal cover. ( 3 ) Hand watering has proven to be inefficent, and ineffective in saturating the soil (M. Martin 2007). In the PNW, where we can expect summer drought conditions, irrigation should be included. ( 4 ) A coconut fiber mesh was used to prevent wind and water erosion, inhibit weed growth and retain moisture. The coconut fiber mesh was effective at reducing erosion and inhibiting weed growth. However, the mesh may have contributed to summer drought conditions on the roof. Much of the water from the sprinklers was absorbed by the coconut fiber mesh and then evaporated without ever reaching the soil (M. Martin 2007). skylights and monitoring gap in coconut mesh (filledequipment with green) image courtesy of M. Martin
CASE STUDY: Zoomazium
pact heads were installed in 2007 to make watering more efficient media: 6”, 65% pumice, 25% yard waste compost, 10% sand products/layers: Coconut fiber mesh, Tr e m c o / P e r m a q u i c k - P Q 6 1 0 0 P E R M A GREEN roofing systems™ maintenance: comparable to a forested area of similar size and makeup on the ground. features: designed to look like PNW forest floor
Woodland Park Zoo . 5500 Phinney Ave. North . Seattle, WA . 98103
i r r i g a t i o n : h a n d w a t e r i n g o n l y, 6 i m -
green roof
Extensive Green Roofs: built:
Merrill Hall Clinton Beach Medina Residence
in design/designed:
Colman Center Stansbury Residence Smith Residence SU Lemieux Library WWU Miller Hall Whitman Sherwood Center Lam Residence Camp Fire Site
Intensive Green Roofs:
graphic by The Berger Partnership
Smith Residence
Merrill Hall
built:
Sunshine Project Juanita Village O n e a n d Tw o U n i o n S q u a r e s Cal Anderson Park 1700 7th The Bristol Apartments NG Commons 333 Elliot
in design/designed:
Colman Center Boylston II 40th and Stone Way Four Seasons Hotel 1 Hotel and Residences 5 t h a n d Ye s l e r 635 Elliot 2201 9th Avenue
Sunshine Project
graphic by The Berger Partnership
Four Seasons Hotel
skylights and monitoring equipment Medina Residence
in design .
Ta c o m a P o l i c e S t a t i o n Magnusson Park Restrooms & Pavilion
comple te d proje cts . d e s i g n e d p r o j e c t s . p r o j e c t s
designed but not used:
The Berger Partnership: Project List
designed but not used
Clinton Beach
pumps, gauges, filters . access . overflow . refill
LEAF SCREEN
CONVEYANCE ACCESS FIRST FLUSH DIVERTER
CISTERN
CISTERN OVERFLOW
PUMPS, GAUGES, FILTERS
REFILL
graphic by The Berger Partnership
Rainwater Collection Surface Leaf Screen Conveyance First Flush Diverter Cistern Pumps, Gauges, Filters
collection surface . leaf screen . conveyance . first flush diverter . cistern .
LEAF SCREEN
rainwater
CONVEYANCE
Components: Rainwater Harvesting
RAINWATER COLLECTION SURFACE
cistern
Attributes:
designer(s)/builder(s): Selkirk Miller Hayashi Architects, Seattle Parks and Recreation, Herrera Environmental Consultants completed: 2003
1
system legend:
2 1 metal roof 2 gutter/downspout 3 leaf/debris catcher 4 3,500 gal. polyethylene cistern 5 1 horsepower (10 amp.) pump 6 2 0 a n d 5 m i c r o n f i l t e r s r e m o v e c h l o r i n e , t u r b i d i t y, c y s t s 7 germicidal UV lamp kills bacteria, viruses, and microorganisms 8 rainwater re-use meter showing gal. of rainwater used since commissioning 9 rainwater is used for toilet flushing and potentially for irrigation 10 r a i n w a t e r i s c y c l e d t h r o u g h t h i s r e c i r c u l a t i o n l o o p on a daily basis to ensure quality 10 Lesson Learned:
plumbing
4
Health Department uncertainty regarding water quality resulted in the recirculation loop (10). The recirculation system is
7
now believed to be unnecessary.
9
8
6
inside of leaf/debris catcher
5 graphics by The Berger Partnership
skylights and monitoring viewing window for rainwaterequipment re-use meter
950 NW Carkeek Park Road . Seattle, WA 98177
3
CASE STUDY: Carkeek Park E.L.C.
cistern
(environmental learning center)
cistern
Lessons Learned:
Attributes:
designer(s)/builder(s): Cascade P e o p l e â&#x20AC;&#x2122; s C e n t e r, M . L u k s a n completed: 2006 system cost: $25,000. The cistern was donated. Design and construction was performed by volunteers.
( 1 ) This system has two first flush diverters. First flush diverters may not be necessary in the PNW due to frequent rain events. ( 2 ) This system partially refills the cistern with city water when the water level cistern top and access hatch
from the volume that can be uti-
to gazebo cistern
lized to store rainwater, resulting in
Transport & Diversion System
Rainwater Collection Surface (roof)
inefficiencies. Pump & Filters filter
inlet
city water
to stormwater system floating ball
stormwater diverter City Water Makeup System pump
10 Gallon First Flush System
17,000 gal.
116 gal.
cistern water to toilet & hose
copper tube electric water pipe heater
cap - to be removed when diverter must be cleaned outlet
access & cleaning hatch
city water
to soil @ 1 l/hr
overflow
70 Gallon 2nd Flush Diverter - located underground
cistern water city water
connected
pump, filters, gauges
copper tube city water
Pump & Filters
17475.9 gal
to stormwater system
mercury float - fills cistern with city water when rain water is nearly depleted
11,000 Gallon Cistern -
donated from old Rainier Brewery
to toilet
115.8 gal
hose for watering garden graphics by The Berger Partnership
cistern water (left) city water (right)
309 Pontius Avenue North . Seattle, WA 98109
the cistern with city water subtracts
CASE STUDY: Cascade Peopleâ&#x20AC;&#x2122;s Center
reaches a low point. Partially filling
cistern
Attributes:
d e s i g n e r ( s ) / b u i l d e r ( s ) : M i l l e rHull Partnership (Arch.), The Berger Partnership (L .Arch.), SvR Design Company (Civil Eng.) completed: 2005
OUT
overflow into bioretention swale and Union Bay
IN
rainwater
green roof Merril Hall roof
green roof
Merrill Hall and UBNA
city water supply used to irrigate greenroof (only used when cistern is empty)
5000 gal. cistern (located underground)
ership r Partn e g r e he B ic by T graph
green roof plants
above the cistern
3501 NE 41st Street . Seattle, WA 98105
M c Va y C o u r t y a r d d r a i n
CASE STUDY: Merrill Hall
OUT
rainwater from: courtyard drains, greenhouse, CUH buildings
cistern
Rainwater Harvesting: built:
Merrill Hall Te r r a c e P a r k K- 8 Islandwood Bayview Center Barret Residence Mullin Residence
in design/designed/designed but not used:
Islandwood rainwater conveyance system
Islandwood linked cistern system
Rainwater Harvesting Pond
Islandwood cistern system
in design .
Cistern Concept
comple te d proje cts . d e s i g n e d p r o j e c t s . p r o j e c t s
Cedarhurst Elementary under const.
designed but not used
Cedarhurst Elem. cistern construction
The Berger Partnership: Project List
Cedarhurst Elementary SU Lemieux Library WWU Miller Hall Whitman Sherwood Center Camp Fire Site Bainbridge Island Residence Medina Residence Murray Residence
designer(s)/builder(s): Runberg
Architecture Group, SvR Design Company (L.Arch. & Civil Eng.) completed: 2005 plants: grasses, dogwood irrigation: drip irrigation media: loamy sand, 3/4” - 1-1/2” pea gravel maintenance: minimal
stormwater planter
Attributes:
water arrives via downspout directly from the roof
roofline, downspouts
loamy sand min. depth of 18”
12” min
3/4” to 1 1/2” pea gravel min. depth of 12”
perforated pipe to collect and drain filtered, infiltrated stormwater
stormwater planter with weeds
graphic by The Berger Partnership
Lessons Learned:
stormwater storage area (from top of overflow to bottom of planter)
( 1 ) This stormwater planter has received little to no maintenance; there are Acer macrophylum weed
seedlings that are nearly 1 story tall. Stormwater planters will require maintenance similar to landscape plantings. ( 2 ) Stormwater planters can be used as stormwater detention facilities. As water filters through the detention system, the additional benefit of pollutant reduction is achieved. ( 3 ) Many plants in this stormwater planter are not performing well or have already died. An irrigation system is installed but not used. Stormwater planters may require irrigation during the summer months. ( 3 ) The dogwood sp. has performed very well in the absence of irrigation. This plant may be well suited to stormwater planters in Seattle. 5 story downspout
230 8th Ave North . Seattle, WA 98109
18” min
round rock used as splash block
CASE STUDY: Denny Park Apartments
overflow
living machine
Attributes:
designer(s)/builder(s): Mithun (Arch.), The Berger Partnership (L.Arch.), 2020 Engineering (System Engineering), RAFN (Contractor) completed: 2003 size: 1,500 sq/ft type: Living Machine™ Generation II living machine plants:
hydroponic reactors: Canna generalis striatus ‘Pretoria’, Zantedeshia aethiopica, Cyperus gigantus, Hedichium coronarium, Calocasia esculenta, Colocasia esculenta “Euchlora”, Alocasia odora, Cyperus papyrus, Scirpus acutus, Salix negra, Salix lucida ssp. Lasiandra, Thalia geniculata constructed wetland: Ledum glandulosa, Andromeda polifolia, Bidens cernua, Iris pseudacorus, Equisetum telmateia, Juncus effusus, Glyceria elata
wastewater f r o m s e v e r a l living machine Islandwood buildings blackwater
IN
non-living machine greenhouse p l a n t s : Cornus canadensis, Oxalis oregana,
Fragaria sp., Vaccinium sp., Spirea densifolia, Gaultheria shallon, Asarum caudatum, Mahonia nervosa, Polystichum munitum
animals: snails, fish, frogs,
microcrustaceans irrigation: living machine plants u s e b l a c k w a t e r, n o n - l i v i n g m a c h i n e greenhouse plants are irrigated with a drip system using treated water from the living machine features: microscope and lab count e r, i n f o r m a t i o n a l s i g n a g e , t r e a t e d water can be used to flush toilets that feed back into the system capacity: can process enough black water to produce 3000 gallons of treated water daily
1
septic tank filter boxes
5
hydroponic reactors h y d r o p o n i c r e a c t o r / c larif ier dosing tank constructed wetland UV treatment
6
7
pond clean water holding tank hics grap
4
3
2
water treatment
9
8 ip ersh artn P r erge he B T y b
non-living machine greenhouse plants
treated water
OUT
vegetation
4450 Blakely Avenue NE . Bainbridge Island, WA 98110
Islandwood building water uses
CASE STUDY: Islandwood
1 2 3 4 5 6 7 8 9
system key:
clean water spout
blackwater
IN
living machine
septic tank
Attributes:
T h e s e p t i c t a n k i s a c l o s e d , a n a e r o b i c r e a c t o r. T h e t a n k t a k e s t h e form of a typical below ground septic tank. Wastewater resides in the tank while anaerobic bacteria break down solids to prepare them for entering the system. Biochemical oxygen demand (BOD) is lowered in the septic tank. BOD is a measure of how much oxygen organisms u s e i n a b o d y o f w a t e r. T h e h i g h e r t h e B O D , t h e m o r e p o l l u t e d t h e w a t e r. B i o s o l i d s w i l l n e e d t o b e r e m o v e d f r o m t h i s t a n k p e r i o d i c a l l y.
Purpose:
Acts as a sedimentation basin to reduce concentrations of BOD and solids.
2
filter boxes
septic tank lid
filter box lids
Attributes:
The filter boxes are closed anaerobic reactors. The boxes are located below ground. Bacteria live in the boxes and begin to break down s o l i d s i n w a s t e w a t e r a n d r e d u c e B O D. B i o s o l i d s w i l l n e e d t o b e p e r i odically removed.
Purpose:
The filter boxes break down biosolids and reduce wastewater odor before wastewater enters the greenhouse.
3
hydroponic reactors
Attributes:
The two hydroponic reactors are large, cylindrical, liquid and biosolid f i l l e d c o n t a i n e r s t h a t a r e o p e n t o t h e a i r. T h e c o n t a i n e r s h a v e s n a i l s , frogs, plants, microcrustaceans and microorganisms such as denitrifying bacteria and floc forming bacteria. Denitrifying bacteria remove nitrogen from the biosolids and floc forming bacteria remove organic materials. These containers are aerated to promote o r g a n i c g r o w t h . T h e p l a n t s p e r f o r m t h r e e f u n c t i o n s : ( 1 ) p r o v i d e s u rface area for microorganisms to colonize and grow (2)perform nutrient uptake (3)provide habitat for organisms to live on.
Purpose:
4
All of the organisms in these reactors live on, and break down organic m a t t e r f r o m t h e w a s t e w a t e r.
hydroponic reactor / clarifier
The s by c i h grap
rship rtne a P er Berg
hydroponic reactor
Attributes:
The hydroponic reactor/clarifier has all of the same attributes as the two hydroponic reactors and has wastewater sorting capabilities. Solids that are not processed enough to enter the constructed wetland are routed back to the filter boxes. Wastewater which has been treated sufficiently to enter the constructed wetland is pumped to the dosing tank.
Purpose:
To e n s u r e t h a t w a s t e w a t e r h a s b e e n t r e a t e d a d e q u a t e l y p r i o r t o e n t e ring the constructed wetland.
hydroponic reactor / clarifier
4450 Blakely Avenue NE . Bainbridge Island, WA 98110
1
CASE STUDY: Islandwood
living machine
dosing tank
Attributes:
The dosing tank is a small reservoir that periodically flushes measured quantities of wastewater into the wetland.
Purpose:
To r e g u l a t e t h e t i m i n g a n d v o l u m e o f w a s t e w a t e r e n t e r i n g t h e w e t l a n d .
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constructed wetland
dosing tank
Attributes:
The constructed wetland has a pea gravel media which functions as a f i l t e r. W a s t e w a t e r i s c i r c u l a t e d t h r o u g h t h e w e t l a n d . T h e w e t l a n d has plants, snails, frogs and microorganisms that break down organic m a t t e r. T h e p e a g r a v e l / w a s t e w a t e r w e t l a n d i s p e r i o d i c a l l y a e r a t e d . The aeration is intended to fluidize the biosolids which are trapped at various levels in the media. The biosolids are then removed from the top of the media.
Purpose:
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T h e c o n s t r u c t e d w e t l a n d a c t s a s a c o a r s e d o w n f l o w f i l t e r, t r a p p i n g waste as gravity pulls wastewater through the media. Water leaving this element is suitable for discharge to surface waters.
UV treatment
constructed wetland
Attributes:
Water from the wetland is subjected to Ultra-violet (UV) treatment for t h e r e m a i n i n g b a c t e r i a i n t h e w a t e r.
Purpose:
To e n s u r e w a t e r q u a l i t y.
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UV treatment
pond
Attributes:
T h e p o n d h a s p l a n t s a n d f i s h . T h e w a t e r i s c l e a r.
Purpose:
To a l l o w v i s i t o r s a n d s t u d e n t s t o i n t e r a c t w i t h t h e t r e a t e d w a t e r a n d show the quality of the water that is produced as an end product.
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4450 Blakely Avenue NE . Bainbridge Island, WA 98110
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CASE STUDY: Islandwood
living machine
Attributes:
clean water holding tank septic tank
This tank is located below ground. Water exiting the living machine is stored here. The water can be used to flush toilets and for irrigation of plants in the living machine greenhouse, which are not part of the wastewater treatment process.
Purpose:
To s t o r e w a t e r t o b e r e c y c l e d b a c k i n t o t h e s y s t e m .
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non-living machine greenhouse plants
treated water
blackwater
building water uses
wastewater from Islandwood buildings
non-living machine greenhouse plants
4450 Blakely Avenue NE . Bainbridge Island, WA 98110
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CASE STUDY: Islandwood