Rainwater Harvesting: A Reliable Alternative in the San Juan Islands

Northwest Water SourceNorthwest Water SourceP.O. Box 2766P.O. Box 2766, , Friday Harbor,Friday Harbor, WashingtonWashington

Office and Home 378Office and Home 378--82528252ee--mail mail water@interisland.netwater@interisland.net

Specializing in water conservation since 1992Specializing in water conservation since 1992

Rainfall CatchmentRainfall CatchmentRainwater HarvestingRainwater Harvesting

A reliable alternative water Source A reliable alternative water Source And stormwater solutionAnd stormwater solution

New ConstructionNew Construction

Rainfall Catchment/Harvesting is approved Rainfall Catchment/Harvesting is approved for permitting new construction in San for permitting new construction in San Juan County as a sole source including Juan County as a sole source including potable.potable.Rainfall Catchment is cost competitive Rainfall Catchment is cost competitive with conventional water sources.with conventional water sources.Water quality from Catchment is often Water quality from Catchment is often better than well water in San Juan County.better than well water in San Juan County.

Cost effectivenessCost effectiveness

Rainfall Catchment is generally 150% the Rainfall Catchment is generally 150% the cost of conventional well systems.cost of conventional well systems.Rainfall Catchment is generally less than Rainfall Catchment is generally less than 50% the cost of seawater desalination.50% the cost of seawater desalination.Seawater desalination may only be done Seawater desalination may only be done directly from the salt chuck. These directly from the salt chuck. These systems be systems be may not connected to may not connected to existing seawater contaminated existing seawater contaminated wells.wells.

Environmental ImpactEnvironmental Impact

Rainfall catchment hasRainfall catchment has”” a net positive a net positive impact on ground water supplies.impact on ground water supplies.Rainfall catchment reduces storm water Rainfall catchment reduces storm water runoff from impervious surfaces by storing runoff from impervious surfaces by storing the water.the water.Water impounded is reintroduced to the Water impounded is reintroduced to the aquifer during dry summer months rather aquifer during dry summer months rather than only during rainy season.than only during rainy season.

Residence of Residence of Andy and Judy Andy and Judy

HengestegHengestegSan Juan IslandSan Juan Island

The following system has been in The following system has been in place for 4 years. This system is place for 4 years. This system is

the sole residential supply.the sole residential supply.

14,000 Gallons Storage14,000 Gallons Storage

San Juan Island home using rainwater harvesting as itSan Juan Island home using rainwater harvesting as it’’s sole water s sole water source. 14,000 gallons of storage located lower than house. source. 14,000 gallons of storage located lower than house.

Approximately 3500 square feet of collection area. Approximately 3500 square feet of collection area.

Can you find the storage tanks in this slide?Can you find the storage tanks in this slide?6 @ 2340 gallon tanks located on naturally screened pad.6 @ 2340 gallon tanks located on naturally screened pad.

Easy to screen, easy to hide storage tanksEasy to screen, easy to hide storage tanks14,000 gallons14,000 gallons

Early Filtration and Ultra Violet disinfection systemEarly Filtration and Ultra Violet disinfection systemHomeowner has also added battery backup and charger on left.Homeowner has also added battery backup and charger on left.

1999 remodel of 4500 square foot home1999 remodel of 4500 square foot homePotable well system declining in capacityPotable well system declining in capacity

new metal roof for collectionnew metal roof for collection

20,000 gallon steel storage tank with 45 mil poly liner20,000 gallon steel storage tank with 45 mil poly linerlocated 60 feet above home, nearly invisible from homelocated 60 feet above home, nearly invisible from home

23 foot diameter X 7 foot wall height23 foot diameter X 7 foot wall height

240 Gallon underground 240 Gallon underground ““ballball”” storage tank storage tank with pump to transfer rainwater to storagewith pump to transfer rainwater to storage

Screened view from residenceScreened view from residence

5000 gallon system for irrigation 5000 gallon system for irrigation only ,storage located under deck on opposite side of house.only ,storage located under deck on opposite side of house.

Shake roof material not approved for potable use.Shake roof material not approved for potable use.

Showing deck with storage belowShowing deck with storage below

6000 gallons storage located under pocket deck on opposite side 6000 gallons storage located under pocket deck on opposite side of of househouse

6000 storage located under second floor6000 storage located under second floordeck on opposite side of housedeck on opposite side of house

5000 gallon PVC bladder 5000 gallon PVC bladder located under master bedroomlocated under master bedroom

irrigation for sitting gardenirrigation for sitting garden

Extensive remodel of log home in Victoria ValleyExtensive remodel of log home in Victoria Valleyvery limited wells with Barium contaminationvery limited wells with Barium contamination

30,000 gallon steel storage tank located lower than home site 30,000 gallon steel storage tank located lower than home site to enable gravity collection. New metal roof systemto enable gravity collection. New metal roof system

All downspouts connected to 4All downspouts connected to 4”” PVC manifold.PVC manifold.Manifold drops into 250 gallon filtration tank at lower Manifold drops into 250 gallon filtration tank at lower

corner of deck.corner of deck.Water gravities 250Water gravities 250’’ to steel 30,000 gallon storage tankto steel 30,000 gallon storage tank

30,000 gallon storage tank with 45 mil poly liner30,000 gallon storage tank with 45 mil poly linerpressure system located adjacent to tankpressure system located adjacent to tank23 feet in diameter X 9 feet wall height23 feet in diameter X 9 feet wall height

Spring Point, Orcas IslandSpring Point, Orcas IslandMetal roof systemMetal roof system

6000 gallons of storage located in crawl space6000 gallons of storage located in crawl spaceIrrigation onlyIrrigation only

6000 gallons of storage located in crawl space below6000 gallons of storage located in crawl space belowdeck on right side of housedeck on right side of house

3 1440 gallon tanks and 1 1100 gallon tank 3 1440 gallon tanks and 1 1100 gallon tank under guest bedroomunder guest bedroom

Rainfall Catchment SystemsRainfall Catchment SystemsLocated on Lopez IslandLocated on Lopez Island

have been required due to have been required due to Salt Water IntrusionSalt Water Intrusion

Grant/Allen ResidenceGrant/Allen ResidenceThis residence has a seawater This residence has a seawater intruded well that exceeds 250 intruded well that exceeds 250

ppm.ppm.A well drilled on the adjacent A well drilled on the adjacent

property also exceeds the Chloride property also exceeds the Chloride limit.limit.

20,000 Gallons Storage20,000 Gallons Storage

New system presently installed fall of 2000New system presently installed fall of 200020,000 gallon steel tank with poly liner20,000 gallon steel tank with poly liner

metal roof systemmetal roof system

All 4 inch PVC collection manifold is located underneathAll 4 inch PVC collection manifold is located underneathexisting decking. existing decking.

Collection system is invisibleCollection system is invisible

20,000 Gallon tank located adjacent to home.20,000 Gallon tank located adjacent to home.Tank filled in less than 3 months.Tank filled in less than 3 months.

Large collection area will ensure enough for household useLarge collection area will ensure enough for household usesome irrigation will be feasible.some irrigation will be feasible.Good source for fire protectionGood source for fire protection

20,000 Tank well screened by trees.20,000 Tank well screened by trees.

Residence of Mark Residence of Mark GregoireGregoire

House well and all neighboring House well and all neighboring properties have wells that exceed properties have wells that exceed

the EPA limit for Chlorides.the EPA limit for Chlorides.

9000 Gallons Storage9000 Gallons Storage

Beachfront home on FishermanBeachfront home on Fisherman’’s Bay Peninsulas Bay PeninsulaCement/clay false Cement/clay false ““shakeshake”” roof systemroof system

safe for potable sourcesafe for potable sourcesalt water intruded wellsalt water intruded well

9000 gallons of storage behind fenced garden9000 gallons of storage behind fenced garden

Detail of cement/clay roofDetail of cement/clay roof

Details of filtration,disinfection and pumping systemDetails of filtration,disinfection and pumping system

Residence located at Mud Bay, Lopez IslandResidence located at Mud Bay, Lopez IslandSteel roof system designed to discharge to a single downspoutSteel roof system designed to discharge to a single downspoutpump located in culvert tank, pumping 60 feet uphill to remote pump located in culvert tank, pumping 60 feet uphill to remote

storagestorage9,000 Gallons Storage Capacity9,000 Gallons Storage Capacity

Water side of Mud Bay homeWater side of Mud Bay homestorage tanks are not visible from homestorage tanks are not visible from home

Mud Bay HomeMud Bay HomeRemote storage tanks above home site, 9000 gallonsRemote storage tanks above home site, 9000 gallons

system was required for building permitsystem was required for building permit

MolitorMolitor home on Shaw Islandhome on Shaw IslandWell failed in capacity due to overdraft by Well failed in capacity due to overdraft by

neighbors.neighbors.

3 2340 gallon tanks under trees barely 3 2340 gallon tanks under trees barely visible just to the right of the porch.visible just to the right of the porch.

FishermanFisherman’’s Bay Peninsula , Lopez Islands Bay Peninsula , Lopez IslandTemporary Mobile Home to be used during construction.Temporary Mobile Home to be used during construction.

4600 gallons storage behind screen to left.4600 gallons storage behind screen to left.System required for building permitSystem required for building permit

FishermanFisherman’’s Bay Peninsula, Lopez Islands Bay Peninsula, Lopez Island4000 gallons in 4 box tanks located under deck4000 gallons in 4 box tanks located under deckmetal roof system, required for building permitmetal roof system, required for building permit

4000 gallons of storage hidden below deck4000 gallons of storage hidden below deckFishermanFisherman’’s Bay Peninsula, Lopez Islands Bay Peninsula, Lopez Island

BakerviewBakerview, Lopez Island, Lopez IslandModular home installed with 4600 plastic catchment tankModular home installed with 4600 plastic catchment tank

system required for building permit because of salt water intrussystem required for building permit because of salt water intrusionion

Bakerview, Lopez IslandBakerview, Lopez Island4600 Plastic water storage tank4600 Plastic water storage tank

bottom set 24 inches below gradebottom set 24 inches below grade

Ideal candidate for rainfall catchment systemIdeal candidate for rainfall catchment system

Easy roof to collect water from.Easy roof to collect water from.

Traub Residence, San Juan IslandTraub Residence, San Juan IslandWell declined and owner installed two 2340 Well declined and owner installed two 2340

gal tanksgal tanks

Added two more 2340Added two more 2340tanks 6 months latertanks 6 months later

New Residence, San Juan Island 3000 gallons of New Residence, San Juan Island 3000 gallons of storage in crawlspace for fire suppression supplystorage in crawlspace for fire suppression supply

2@15002@1500 gallon tanks in crawlspacegallon tanks in crawlspace

Approved Hydrant outside corner of house nearest Approved Hydrant outside corner of house nearest driveway for access.driveway for access.

Borner residence, Shaw IslandBorner residence, Shaw Island20,000 gallon rainfall catchment system20,000 gallon rainfall catchment system

20,000 Gallon Storage Tank20,000 Gallon Storage Tank

Pump, Filtration and Disinfections in insulated Pump, Filtration and Disinfections in insulated locker.locker.

Johnson HomeJohnson HomeNew construction, San Juan Island Saltwater intruded well.New construction, San Juan Island Saltwater intruded well.

9,000 gallons storage under new deck9,000 gallons storage under new deck

Finished HomeFinished Home

9,000 gallons of storage installed before 9,000 gallons of storage installed before construction under future deck.construction under future deck.

Tanks enclosed within Deck. Screened from view.Tanks enclosed within Deck. Screened from view.

County Commissioner Millers Strawbale home, Lopez County Commissioner Millers Strawbale home, Lopez Island. Rainfall Catchment, Composting toilet, Island. Rainfall Catchment, Composting toilet,

Greywater Greenhouse.Greywater Greenhouse.

Greywater GreenhouseGreywater GreenhouseMiller residence, Lopez IslandMiller residence, Lopez Island

Greywater Greenhouse Greywater Greenhouse viewed from inside living roomviewed from inside living room

Savage/Wooten residence, Shaw IslandSavage/Wooten residence, Shaw IslandDual system potable from wellDual system potable from well

all other water from rainfall catchmentall other water from rainfall catchment

Collection tank with pump to transfer to Collection tank with pump to transfer to storage tanks, remote on property.storage tanks, remote on property.

8,400 gallons rainfall storage8,400 gallons rainfall storage600 feet from house600 feet from house

Potable and nonPotable and non--potable pumpspotable pumpstank on left is storage for potable welltank on left is storage for potable well

Lopez SchoolLopez School

Lopez School has been supplied from a distant well for Lopez School has been supplied from a distant well for several years. Due to concern with Salt Water several years. Due to concern with Salt Water

Intrusion, Intrusion, Northwest Water Source is designing a rainfall Northwest Water Source is designing a rainfall

catchment system for total use of the school complex.catchment system for total use of the school complex.Washington State Department of Health will allow the Washington State Department of Health will allow the design if treatment meets drinking water standards. design if treatment meets drinking water standards. There will be a 120,000 gallon raw water tank located There will be a 120,000 gallon raw water tank located elsewhere on the property. Filtration will be by elsewhere on the property. Filtration will be by ““Bag Bag FiltersFilters””, with both Ultra Violet and Chlorination for , with both Ultra Violet and Chlorination for

disinfections. School buildings will produce over 1.5 disinfections. School buildings will produce over 1.5 million gallons per year.million gallons per year.

Lopez SchoolLopez School

Huge Collection AreaHuge Collection Area

New Home, RosarioNew Home, RosarioCatchment required due to moratorium on water Catchment required due to moratorium on water

connectionsconnections

Factory built house, Raster block foundation, Factory built house, Raster block foundation, pannelizedpannelizedstructure and roof. 4 2340 gallon tanks on right.structure and roof. 4 2340 gallon tanks on right.

Another new home on Orcas Island, Moratorium Another new home on Orcas Island, Moratorium on community system. Building permit issued on community system. Building permit issued

based on rainfall catchment.based on rainfall catchment.

4 2340 gallon tanks located at back of 4 2340 gallon tanks located at back of building against setback for property line.building against setback for property line.

Home on Shaw IslandHome on Shaw IslandFlat Flat TorchdownTorchdown roof, built in downspoutsroof, built in downspouts

Raincoat 2000 NSF approved potable coating.Raincoat 2000 NSF approved potable coating.

Bob Tremble, Shaw Island, Flat Roof

Bob Trimble and Jim Bob Trimble and Jim ReuscherReuscher inspecting new roof inspecting new roof coating.coating.

North View of Trimble roof.North View of Trimble roof.““Raincoat 2000Raincoat 2000”” potable coating systempotable coating system

Restoration of historic Anderson cabin, Orcas Restoration of historic Anderson cabin, Orcas Island. No well, existing catchment systemIsland. No well, existing catchment system

rebuild system and install 10,000 gallon tankrebuild system and install 10,000 gallon tank

Nice little 10,000 gallon tank tucked in Nice little 10,000 gallon tank tucked in the trees.the trees.

Very nice lady with more garden than water, Orcas Is.Very nice lady with more garden than water, Orcas Is.Collection system with over 1000 feet of collection pipeCollection system with over 1000 feet of collection pipe

50,000 tank located at base of cliff below house.50,000 tank located at base of cliff below house.

50,000 gallon tank at bottom of cliff50,000 gallon tank at bottom of cliff

Martin home on Lopez IslandMartin home on Lopez Island20,000 gallon tank to be located 100 feet above 20,000 gallon tank to be located 100 feet above

Installation of underground pipeInstallation of underground pipe

Installation of 240 inInstallation of 240 in--ground ball tank to collect water from rooftopground ball tank to collect water from rooftopand house deep well pump to shuttle water to 20,000 tank above and house deep well pump to shuttle water to 20,000 tank above

househouse

Construction of steel tankConstruction of steel tankFoundation of crushed rock and compacted sandFoundation of crushed rock and compacted sand

with cement pavers for support of steel tankwith cement pavers for support of steel tank

Liner Installation. All Fittings through floorLiner Installation. All Fittings through floor

San Juan Island Fire San Juan Island Fire Dist. 3Dist. 3

San Juan Island Fire District #3 is San Juan Island Fire District #3 is building a new 9000 sq.ft. building a new 9000 sq.ft.

firehouse. They have an excellent firehouse. They have an excellent well, but have decided to fill their well, but have decided to fill their new 30,000 gallon water storage new 30,000 gallon water storage tank from rainfall catchment. The tank from rainfall catchment. The storage tank if for fire truck water storage tank if for fire truck water

supply and building sprinkler supply and building sprinkler system.system.

New 9000 sq.ft. firehouse with New 9000 sq.ft. firehouse with storage tank located behind storage tank located behind

building.building.

District #3 firehouse view from District #3 firehouse view from south.south.

30,000 gallon tank, Fire Dist #330,000 gallon tank, Fire Dist #3

Existing house, Port Stanley, Lopez Existing house, Port Stanley, Lopez Island due for remodel summer 2002. Island due for remodel summer 2002. Well has been contaminated with sea Well has been contaminated with sea

water. Will do metal roof and water. Will do metal roof and catchment.catchment.

Rainfall InformationRainfall Information

You may use the average rainfall You may use the average rainfall for selected locations in San Juan for selected locations in San Juan

County to complete the above County to complete the above worksheet. Average water use worksheet. Average water use per person/per day is 50 to 60 per person/per day is 50 to 60 gallons. There is gallons. There is nono allowance allowance for irrigation which is generally for irrigation which is generally

not recommended .not recommended .

Rainfall Catchment Rainfall Catchment Water BudgetWater Budget

You may use this worksheet to You may use this worksheet to estimate storage and catchment estimate storage and catchment area requirements to suit your area requirements to suit your

needsneeds

Rainfall Catchment Water Budget for FeasibilityNumber of Users 2Gallons per day/person 50Supplement from well 0

STEP 1 Gallons required per day 100 (users x gpd/p =)Days in residence/year 365

STEP 2 Total water use per year 36500 (gpd x days =)Rainfall 22Water per sq.ft./inch of rain 0.623

STEP 3 Gallons water/sq.ft./year 13.706 (rainfall x .623 =)Total water needed per year 36500Gallons water/sq.ft./year 13.706

STEP 4 sq.ft.collection area needed 2663 (water needed/gpsqft =)Days storage required 90Gallons required per day 100

STEP 5 Gallons of storage required 9000 (days stg x gpd =)System requirements for the above system are as follows

Rooftop catchment collection area required for this design based on rainfall in the surrounding neighborhood

REQUIRED 2663 sq.ft.Storage capacity required to supply system for periods without rain (summer)

REQUIRED 9000 gallons

ROOF TOP COLLECTION AREA Sq. Ft.Main House 2700

Studio

GarageTOTAL COLLECTION AREA PROVIDED 2700TOTAL WATER AVAILABLE ANNUALLY 37006TOTAL WATER STORAGE REQUIRED 9000

Average rainfall at selected locations in San Juan County

All roofing material to be enameled metal or other approved impervious surface. Average Rainfall by location

South Lopez 15"/yrSouth San Juan 18/yrFisherman's Bay 20"/yrFriday Harbor 22"/yrCentral San Juan, North Lopez 24"/yrShaw, Henry, Crane 26"/yrRoche Harbor, Orcas Landing 27"/yrDeer Harbor, West Sound, West Orcas 28"/yrEastsound, Buck Mt., N.W. Orcas, Waldron 29"/yrOlga, Pt. Lawrence, Obstruction Is. 32"/yrNorthshore Orcas, Mt Constitution, Twin Lakes 35"/yr

Northwest Water Source dba Greywater Management, Inc. Friday Harbor, WashP.O. Box 2766, 378-8900, fax 378-8790……….e-mail..water@waterstore.com

Directions for use of this work sheet.

Choose the average rainfall from the listing at the bottom of page oneadjust the variables (red figures above) for your conditionsnote requirements (blue figures above) to size your systeminsert planned structures (green figures above) to determine whether the proposed structureis of adequate size to supply required water. Don"t downsize storage required if you have more than adequate roof footprint. roof pitch has no bearing on catchment area except in areas of high wind during storms.

All math formulas are already in this worksheet. If you change the variables, the required totals willautomatically change with them. If you have any questions, Call Tim Pope at 360-378-8900 or evenings a360-378-8252. Happy water prospecting!

Documents required by San Documents required by San JuanJuan

County, Washington for County, Washington for building permit for new home building permit for new home using Rainwater Harvesting using Rainwater Harvesting as a sole source including as a sole source including

Potable.Potable.

OUR OFFICEOUR OFFICE

Thank You.Thank You.Tim Pope, Northwest Water Tim Pope, Northwest Water

SourceSourceP.O.Box 2766, Friday Harbor, WA 98250P.O.Box 2766, Friday Harbor, WA 98250

360360--378378--8900 8900 –– fax 360fax 360--378378--8790 8790 –– home 360home 360--378378--82528252ee--mail water@waterstore.commail water@waterstore.com