Water Management Strategies

Page 1

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

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12 40 lifespan yrs

$low cost|$high cost per SF

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100

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lifespan yrs

10 40 $low cost|$high cost per SF

70

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Intensive green roof >10”

Semi-Intensive green roof 6-10”

30

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dia

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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

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i ter ma

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$low cost|$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

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xti ote

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%mitigated stormwater

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SYSTEM COMPARISON: Green Roofs

$20

22 20 re tu uc r t s

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%mitigated stormwater|%runoff

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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

6�

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 � 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 ’ 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 People’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 .

6

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:

7

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.

8

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.

by hics grap

The

hip ners Part r e Berg

pond

4450 Blakely Avenue NE . Bainbridge Island, WA 98110

5

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 .

ip ersh artn P r e Berg The y b hics grap

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

9

CASE STUDY: Islandwood


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