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Engineers Without Borders-USA Mid-Atlantic Professionals Chapter Water for Life Project Apatut, La Union, Philippines . Apatut – Community Overview. Located approximately 200 miles northwest of Manila Approximately 750 residents Approximately 300 students at school
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Engineers Without Borders-USAMid-Atlantic Professionals ChapterWater for Life ProjectApatut, La Union, Philippines
Apatut – Community Overview • Located approximately 200 miles northwest of Manila • Approximately 750 residents • Approximately 300 students at school • Predominantly farming community • Large variations in income, water access, and home quality across community
The Problem: Apatut residents obtain water from shallow wells that show high levels of fecal coliform in water quality tests 7 of 8 wells tested show contamination above allowable levels Community members suffering from illnesses associated with poor drinking water quality, such as diarrhea, dysentery and stomachache Access to clean, consistent source of water is not equitable across the community In some cases, wells built immediately adjacent to latrines
EWB-MAP Project Goals • Provide clean, potable water at school (primary goal of community) • Provide clean, potable water at centralized faucets (Phase 1) and to every house in community (Phase 2) • Ensure equitable distribution of clean, potable water throughout the community • Get community ‘buy-in’ by incorporating community feedback during design phase and community labor and financial donations during construction phase • Facilitate project sustainability by providing financial and operation and maintenance training to Water Cooperative
Local Partners • Rotary: Rotary Club of Suburban East Rizal and Rotary Club of San Fernando La Union • Robert Osoteo – Primary land donor • Community – established Water Cooperative • Saint Louis College – aided with site surveying
March 2010 EWB-MAP Assessment Trip • Meetings with Water Cooperative members, local Rotary Clubs, St. Louis College, Apatut residents • Inspected ‘mountain spring’ – not a spring, ruled out as water source • Collected water samples from shallow supply wells and ‘spring’ – shallow wells show contamination • Repaired well pumps at school • Completed surveying with St. Louis college • Walked proposed pipeline run • Conducted visual inspection of soils – classified as SM based on Unified Classification System • Met with local well driller and local electric company representative • Evaluated tank and well sites • Completed health surveys • Installed solar data collector to evaluate applicability of solar powered system components
PROPOSED DESIGN: Gravity-Fed Potable Water System with Centralized Taps Alternatives Analysis
Water Demand Calculations Assumptions • 30 gal/capita/day residential; 1 gal/capita/day school • 25-year design life • 2% annual Growth – Growth Rate = 1.49 used (Ref: Technical Note No. RWS 5.D.2, Designing A Ground Level Storage Tank)
System Profile • Pipeline configuration modeled using EPA-NET hydraulic modeling software and survey data to identify pipe sizes • Minimum 30 psi pressure used at outlet • Demand of 30 gpcd for residential and 1 gpcd for school were used • Demand patterns for residential usage and school usage were developed from conversations with residents.
Deep Well Well Site • Need 26 GPM minimum • Pump Testing to be completed after well install • Rotary or Hammer drilled • Approximately 120 feet deep based on driller estimates • Overburden Construction • 6” diameter PVC • Well to be developed after install
Pump Selection • Total Dynamic Head Calculations • Assumptions: • Pump Set at 195 fbgs (worst case) • Storage tank elevation 325 feet • Pump elevation 141 feet • Losses of 70 feet observed • Total Dynamic Head = 195+184+70 = 449 ft • Brake horse power (BHP) Calculations • Assumptions: • Flow is 26 gpm • Total Dynamic Head = 449 ft • Specific Gravity (SG) Water = 1 • Efficiency = 70% • BHP = Flow x Total Dynamic Head x SG / • (3,690 x Efficiency) • BHP = 4.55 horsepower
Storage Tank Tank Site • Designed by licensed structural engineer • Concrete Block, reinforced constructed on slab • 20’-8” by 20’-8” by 8 feet tall • With interior clearance of 12” to 18” from roof, capacity = 20,774 to 22,374 (81-88%) of the daily water supply demand • High-level and low-level floats interlocked with pump
Electrical Supply and Connections • All electric work to be completed by locally-licensed electrician under oversite of EWB-MAP technical lead • Electrical work to include: • Obtain a single-phase power drop from local power company • Connect a main control panel (MCP) to the power drop • Install a transformer • Create a system ground • Create an emergency stop (E-STOP) button on the MCP • Connect the 5 HP submersible pump to the MCP • Connect the peristaltic pump (chlorine supply pump) to the MCP • Connect high level and low level floats in the tank to the MCP • Create interlocks
Tapstands • 3 community tapstands • Each tapstand will include three taps with faucets • 1 tapstand for the school • This tapstand area will include one set of three taps with faucets (as available in the community) and one set of three drinking water fountains (constructed the same as tapstands with a fountain mouthpiece)
Water Treatment • Unable to test water until well is drilled • Well will be cased to mitigate vertical migration of impacted surficial aquifer • Based on size of community, required to disinfect by Philippine government • Proposed Treatment: Bag filter and in-line chlorine disinfection (2-3 ppm) • Treatment units to be housed in small pump house located adjacent to wellhead • Additional treatment to be added as required based on results of water quality testing
Watershed Protection • During construction, EWB-MAP will educate the community on the importance of protecting the watershed. • The immediate area surrounding the deep well (30 feet to the north, 90 feet east and west and 300 feet to the south) will be marked off-limits from development and activities that could contaminate the groundwater (building homes, farming, grazing, etc.) • Any bare area shall be planted with native grasses and/or planted with trees as appropriate. • Failed reforestation efforts observed during assessment trip - the project team believes that a properly sized planting area may not have been properly loosened. The team has developed a simple planting detail and instructions to help residents • Soil analyses for nutrient and other elements should be done and recommendations for soil amendments developed based on those analyses.
Construction Process and Safety • EWB-MAP to hire local General Contractor to manage subcontracting, materials acquisition, and construction progress in EWB-MAP’s absence • EWB-MAP to be onsite for the following activities: • Mark-out pipeline and initiation of trenching/backfill • Minimum of one road crossing • Minimum of one stream crossing • Minimum of one tap stand • Initiation of well install • Completion of well install • Well Capacity Testing • EWB-MAP to oversee high-risk activities: well drilling and electrical connections • All activities to be completed in accordance with the site-specific HASP, approved construction methods, and by individuals properly trained and experienced in task at hand • Proper PPE shall be worn by EWB-MAP at all times • Well Sampling • Hydrostatic Pressure Testing • Electrical power drop • Electric connections • System interlock testing • System start-up • Water Cooperative Training
Operation & Maintenance • Inspection, Operation & Maintenance Manual will be provided to community • Includes schedule for inspection/maintenance and associated logs • Designated Water Cooperative members will be trained in inspection and maintenance procedures by EWB-MAP during construction/system startup • Estimated O&M fees
Water Rights and Water Equity • Water Cooperative applied and paid fees for well permit • Memorandum of Agreement between EWB-MAP, Water Cooperative, and community members • Establishes project ownership and maintenance requirements • Provides written agreement for land donation (as needed) for project construction on private land • Identifies residential fees for water use
Sustainability Measurements • Health: measured via health surveys 2 and 5 years after system completion • Goal: Improved health conditions based on original health surveys • Water Quantity: measured via flow meters at tank and tapstands • Goal 1: Supply sufficient to meet current and future demands • Goal 2: Water equitably distributed and used by all residents • Water Quality: tested by certified labs • Goal: 100% of samples with concentrations below Philippine National Standards for all tested parameters • Financial Stability: determined using financial documents from Water Cooperative • Goal 1: Water Cooperative able to afford maintenance, repairs, and upgrades • Goal 2: Water Cooperative able to successfully and routinely collect fees • Technical Stability: determined using repair and maintenance logs in O&M manual • Goal 1: Inspection and maintenance conducted on a routine basis • Goal 2: No service outages are experienced as a result of poor maintenance