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Water, Sanitation & Hygiene Technology. Technical Issues. Wells. Shafts that penetrate the ground to access groundwater Two types of wells Large diameter Small diameter . Large Diameter Wells. 1 to 3 meters (3 to 10 feet) in diameter Usually hand dug Up to 60 meters (200 feet) in depth
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Water, Sanitation & HygieneTechnology Technical Issues
Wells • Shafts that penetrate the ground to access groundwater • Two types of wells • Large diameter • Small diameter
Large Diameter Wells • 1 to 3 meters (3 to 10 feet) in diameter • Usually hand dug • Up to 60 meters (200 feet) in depth • Lined with stones, brick or concrete rings in soft soils to prevent collapsing, no lining needed in strong soils/rock • Should be covered to prevent surface contamination from entering the well • Should be fitted with a pump to extract the water • Powered by hand, wind, solar • Buckets or other such containers lowered by rope are typically used • increase chance of contamination if not properly stored
Small Diameter Wells • “Tube wells" or "boreholes“ • 150 to 300 millimeters (6 to 12 inches) in diameter • Usually machine drilled or hand augered • Practical maximum depth for water is 150 meters (500 feet) • pumping by hand is very difficult at this depth • Borehole is cased with usually PVC pipe to prevent collapsing • slotted to allow groundwater to enter the borehole • Typically fitted with a pump • Powered by hand, diesel/gas/electric motor, wind, solar • Apron and spillway constructed around the borehole to carry wastewater away from borehole
Springs • Where water flows naturally out of the ground • An improved spring is one that is enclosed, usually by reinforced concrete, to prevent surface contamination from entering the water • The "extention" refers to the piping that extends from the spring enclosure ("spring box") to a water storage tank and/or the point of collection ("tap stand")
Rain Catchment Systems • Collection area – impermeable surface • Rooftop – corrugated iron • Ground – paved • Storage tank • Sizing – Supply vs. Demand • Supply – Rainfall and Catchment area size • Demand – Water usage • Above or below ground • “First Flush” mechanism • Divert first 20 liters of rainwater • Prevent leaves, dust, bird droppings from entering tank • Need most recent 20-year average monthly rainfall data • Smooths out abnormal rainfall events
Hand/Foot PumpsHuman-Powered • Groundwater extraction • India Mark II • Surface water extraction • Rivers, Lakes, Ponds • Treadle pump
Other Pumping SystemsNon-Human Powered • Motorized • Diesel, Gas • Windmills • Electric • Solar • Electric • Expensive • Solar collector panels
Latrines • Pit latrines • Pit, slab w/ drop hole and cover, superstructure • Simple • Ventilated Improved Pit (VIP) • Same as Simple but with pipe installed to vent noxious gasses • Drop hole needs to be covered • Schools • One latrine per 30 male students • One “block” of 3 latrines for 90 male students • One latrine per 25 female students • One “block” of 3 latrines for 75 female students
Ecological Sanitation • Arbor Loo • Land available to construct annually • Fossa Alterna • Best in congested areas
Handwashing Stations • Position in critical areas • Near latrines • Near kitchens • Near eating areas • Provide soap and hand drying towel • Be careful of tipping! • Can be constructed of local materials • Terracotta pots (water storage vessels)
Water, Sanitation & Hygiene Key Issues for CRS Programs
Key Issues Water and sanitation is gaining increasing attention within the donor community, including USAID, UN agencies, foundations, corporations and private individuals. CRS is expanding its water and sanitation activities with particular emphasis given to increasing the number of people served with basic drinking water supplies and household sanitation facilities. To date, over 100 million people have been served by CRS water projects. Current CRS water sector programming occurs in more than 40 countries with annual expenditures exceeding $35 million. Regions with growing CRS water and sanitation programs include EARO (Ethiopia, Kenya, Sudan), LACRO (El Salvador, Guatemala, Honduras, Nicaragua), WARO (Ghana, Burkina Faso, Niger, Mali) and South Asia (Afghanistan, Pakistan).
Key Issues (cont) • The CRS vision is to become a leading NGO in international water development by • Expanding water and sanitation services in countries, • Participating in innovative partnerships and coalitions, • Promoting integrated water resources management, and • Providing advice on policies and programs to Congress and USAID. • CRS water sector programs include greater emphasis on intersectoral activities, by incorporating • Water, sanitation and hygiene in home-based care of HIV/AIDS clients • Peacebuilding and conflict prevention in water projects • Watershed and natural resource management in water basin development • Integrated water and agriculture into food security programs
Key Issues (cont) • Donor resources from U.S. dioceses, religious orders, universities and private foundations can be channeled by CRS to needy communities, local partners and country programs. • Donor support for water and sanitation may include • Unrestricted funding (to be used within CRS water sector programs) • Dedicated funding for • Equipment (pumps, water well drilling rigs, water treatment kits) • Field programs (improved water and sanitation services in designated areas) • Staff development (staff exchanges, training courses, interns) • Innovations (application of new technologies, strengthening of local partners, promotion and advocacy campaigns)
