Rainwater Harvesting: A Reliable Alternative in the San Juan Islands
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Transcript of 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 [email protected]@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………[email protected]
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 [email protected] [email protected]