Presentation on theme: "Water, Water Everywhere.... Never mind saving for a rainy day. How about saving for a dry one?"— Presentation transcript:
Water, Water Everywhere.... Never mind saving for a rainy day. How about saving for a dry one?
Archeological evidence show rainwater capture 4000 years ago Ruins of cisterns built as early as 2000 BC are still standing in Israel.
Rainwater Renewable, sustainable high quality water source It is soft, neutral in pH Free from disinfection by-products, salts, minerals, and other natural and man-made contaminants
IS IT SAFE? Absolutely -providing it is collected, stored and disinfected correctly.
Rainwater Harvesting System Four main functions: catch rainwater from the roof and gutters transport the water through the downspouts and pipes remove debris and clean the water store the water
Rain Harvesting Systems As simple as capturing rain in a barrel for gardening
from architects, engineers, and filtration/water treatment specialists Or Complex Requiring input from
Types of systems Full: no other source of water, total house system Partial: back up well or city water: gardening, flushing toilets, laundry Occasional: seasonal, gardening
Collection Techniques Above ground outdoor are Simple: –reduce the amount of debris, pollen, bird droppings or organics from getting into the barrel. –Protect the barrel/tank from UV –Control access to mosquitoes
For Indoor Use More attention and commitment Debris catchment devices and filters First flush diverter Pumps and piping Filters and disinfectants Maintenance and seasonal cleaning Testing
How Much Water Do I Need? Start by looking at your water practices. Are there ways to conserve water on a daily basis?
Indoor Water Conservation Average Indoor Water Use –Toilet flushing - 40% –Bathing % –Laundry % –Cooking / Dishwashing - 10%
Water Saving Appliances Water saving appliances pay for themselves in 1 or 2 years because they reduce the size and the capital cost of the cistern (ie. less water needs to be stored). Water-saving appliances –Faucet aerators and efficient showerheads –Low water use dishwashers and washing machines –On-demand hot water units –Composting toilets.
Toilets Low flush toilets lower indoor water use by as much as 15% & pay for themselves in a year.
Toilet Reuse of Grey Water
Summer Outdoor Water Use 1 watering can = 3.3 gal. 3 ft. shrub in hot weather (1 week) = 7 gal. 18 in. pot in hot weather (1 week) = 1.8 gal. 40 deck pots – drip water (1 week) = 50 gal 1 sprinkler full flow (for 1 hour) = 240 gal. Car washing (1/2 hour) = 120 gal. Pressure washing (1/2 hour) = 40 gal.
Decision #1 What do you want your system to do?
A few basic considerations before you get started: –Annual Monthly Rainfall –Catchment Size –Tank Size –Cost
Portland Monthly Average Participation Jan Jan Jan Annual Average 4.09 Feb.96Feb8.06Feb3.14 March3.01March5.54March4.14 April8.97April4.47April4.26 May2.32May1.09May3.82 June3.33June3.88June3.28 July4.64July3.32 Aug3.23Aug3.05 Sept3.22Sept3.37 Oct6.37Oct4.4 Nov4.21Nov4.72 Dec3.79Dec4.24
Catchment Size How much rain will my roof collect? Measure the perimeter of your roof then calculate the area as if the roof were a flat surface (like a floor plan)
Measure the roof ignoring the angle of the roof. Length x Width gives us the square footage. 20’ x 50’= 1,000sq. Ft. Bird’s eye view 50’ long 20’ Wide
Calculate Potential Catchment Portland annual rainfall: in per yr (or 3.82 ft) Roof Area 20’ X 50’ = 1000 sq ft 3.82’ of rain/yr X 1000 sq ft= 3820 cu.ft x.80 = 3056 cubic ft. (assuming an 80 % efficiency of collection)
7.5 gallons = one cubic foot 3056 cubic ft x 7.5 gal./cubic ft = 22,920 gallons per year
How Much Water Do You Use? To determine the size of the tank and how much water you will need, you must calculate how much water your household uses in a day.
Indoor Water Use Most homes use gallons per person per day. Conservation minded households use G/P/D and some are as low as G/P/D.
To Calculate How much your family uses, here are some of the factors: Total Number of People in the Home
Bathroom Showers: Number of showers. length of showers, flow rate (gallon per minute of the shower head) Baths per week, amount of water in tub
Toilets: Number of time each person flushes, gallons per flush Faucets: times per day to shave, brush teeth, wash hands and minutes per use
Dishes/Laundry Dishes: how many dishes do you wash by hand, minutes water run with each wash, times dishes washed by dishwasher, times used per week, gallons per load (15 normal) Laundry: loads per week, water per load (55 gal normal)
Outside Water Use Lawn or garden watered times a week, minutes watered Other uses: wash Car, fill pool, rinse furniture, clean equipment minutes per week
Water Use Calculator Found on the web Allows you to enter all of your data and gives you the gallons per day used by your family
So, let’s say you conserve water and have 4 members in your family. 4 x 30 gal per person = 120 gallons a day for the whole household.
What size of tank does your family of four need? Using rainwater as your primary water source, you need to consider how much of a reserve your household will require.
With an average of 3 inches per month, we still need to consider the possibility of a 50 day drought. 120 gallons per day x 50 days of drought = 6000 gallons
If you want the full home system, the tank needs to be 6,000 gallons. All indoor use systems share basic components and considerations.
Roof Material Gutters and Downspouts Roof Washing Storage tank Distribution System Filtration Installation Costs
The Roof Non toxic and inert (non leaching.) This is particularly true of the roof that is subject to the oxidizing affects of sun and air borne pollutants. Avoid lead flashings around sky lights or plumbing vents.
Water Quality Water quality varies dependent on: Type of roof material Climate conditions Surrounding environment
Water Quantity The quantity of rainwater that can be collected is also a function of roof texture. The smoother the better.
Metal Roof Most common roofing material used for rain catchment is galvanized metal that has been painted or enameled with a non- toxic material (lead free).
Other surfaces may be used if they do not contain lead, zinc coatings, or copper. Acceptable roofing also includes slate, reinforced concrete, cement tile, and terracotta tile
Asphalt Shingles Asphalt shingles produce less water and are harder to keep clean. Beware of the shingles that contain moss inhibitors for bathing and drinking.
Cedar Roofs Water collected from cedar roofs is acidic for plants and is impractical for indoor use.
Gutters The most common gutters are one-piece, baked aluminum gutters. Half-round vinyl is also excellent.
Gutters and downspouts must be lead, zinc, and copper free
Areas where the water can pool collect insects, organic materials and bacteria. Think of a gutter as a river - not a wetlands or swamp.
Gutter Guard + Keeps some debris out - Protects the debris that collects in the gutter from the sanitizing and self cleaning of sun and wind.
Debris Traps Clean the water before it enters storage A small leaf trap and cleanable pipe systems to catch the larger heavier debris may be all that is required.
Downspouts Anything from non- copper chains to traditional aluminum downspouts can be used to get the water down from the gutters
First Flush Amount of water to flush depends on: Roof and gutter slope Roof material smoothness End use Rain intensity Airborne pollutants (dust, smoke, auto exhaust) Tree debris
Potable System First Flush Flush the first 0.02 inch of rain. Or 10.4 gal per 1,000 sq ft of catchment area.
The WISY Vortex Underground Filter Handles a ton of rainwater Installed underground Standard size for roof areas of up to 5000 sq ft. Small size for roof areas up to 2000 sq. ft. Self-cleaning filter Captures over 90% of the rainwater
The WISY Vortex Underground Filter Water comes in Water to tank Overflow and debris outlet Filter Ground level
Storage Tank Where are you putting it: Aboveground, under ground, in home Most common residential tanks: Concrete, PVC, Fiberglass
PVC…above ground Tank at Jackson Marine Lab University of New Hampshire Least Expensive Easy to Install 300-3,000 gallons Seasonal Use Dark colors (UV protection) Gravity flow or pump
Indoor PVC Tanks gallon Fits through existing doorways Can connect multiple tanks Weight on cellar floor may be an issue
Custom Concrete Tanks Under the home Under the deck
Prefab Concrete Tanks 1000 Gal Septic Tank Remove baffles Add one opening for water to return to house Genest Concrete
Concrete Tanks for Potable H 2 0 Solvent-Free Coatings: Helps Waterproof the tank Environmentally friendly No taste or odor No leaching CHEMTHANE 4200PW, Enviroline & AmTec
Fiberglass Tanks Underground Four Season Safe, long-term storage of potable water Large capacity Expensive
WISY Floating Suction Filter Back Flow Preventer Fine Gauge Particulate Filter Mesh Float Ensures water is extracted where it is the cleanest.
Distribution System Grundfos MQ3 Pump Recommended by Texas Guide to Rainharvesting Compact, easy to install and operate. Pressure switch and tank built in Self priming and water-cooled, low noise level. User-friendly auto reset, alarm if dry running or overheating. Anti-cycling feature prevents the pump from repeatedly starting and stopping in the event of a dripping tap or a minor leak. Stops when the tank is dry, and restarts automatically when water is available again.
Treatment of Rainwater Simpler than treating water from wells Remove parasites, bacteria, and virus from bird droppings, as well as insects, and wind blown materials that are carried onto the roof. Toxins leached from the roofing system can include heavy metals, petroleum products, algae, moulds, and yeast.
Carbon Filter Does not change pH of water Pre-treatment for Reverse Osmosis and UV systems 0.5 micron carbon block filters remove cysts ( Giardia and Cryptosporidium).01 filter inhibits Viruses
Change filters regularly: Susceptible to mold… Filter collects “garbage” in your water Taste change means change the filter… Reduced efficiency the longer they are used
Minerals Minerals in solution can still permeate a charcoal filter. Are essential for health.
Ultraviolet Light Purification Non-chemical approach No harmful bi-products or chemicals Does not alter the taste, pH or other properties of the water Not harmful to your plumbing or septic system Removes some volatile organic chemicals, Low Maintenance Easy and cost effective to install and maintain
Reverse Osmosis Systems Ultrafiltration: Extremely fine membrane allow water molecules, but not larger compounds. The contaminated water is put on one side of the membrane and pressure is applied to stop, and then reverse, the osmotic process. Takes a lot of pressure, is fairly slow, but results is extremely finely filtered water.
Reverse Osmosis Reduces Calcium Deposits Improves Taste, Odor, and Quality of Water Removes Existing Scale Reduces the Need for Household Chemicals Requires No Chemical or Salt Regeneration
Reverse Osmosis Requires high water pressure Water pressurization system may be required. Plumbing work necessary More costly replacement membranes Removes Minerals
Water Distillers There is a growing awareness of distilled water's effects on the balance of minerals in the body, plus the acidic result that a typical distiller creates. Dissolved minerals in the water are more natural than pure water, and serve an important function in supporting the body's immune system and metabolism. Water without minerals can be a health problem. According to the U.S. EPA, "Distilled water (which is identical to RO water ~Ed), being essentially mineral-free.
Installation Costs Roof Material Excavation Tank Plumber