Las Delicias Water Project_ Piping System Design - ewbelsalvador

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Las Delicias Water Project_ Piping System Design - ewbelsalvador Powered By Docstoc
					   Las Delicias,
    El Salvador
Water Supply Project
    Implementation Proposal Phase I
         Trip Dates: May 2012
      Presented to TAC: March 6, 2012
             Presentation Outline
• Overview of Las Delicias Community
• Current Water Supply System and Challenges
• Proposed Improvement to Water System
   – Summary of alternative analysis
   – Phase I (May 2012)
      • New Water Tank at Intermediate Elevation
      • New Supply pipeline and distribution pipeline
   – Phase II (Fall 2012)
      • New pump (or VFD)
      • Improvements to distribution system
      • Control system improvements and pumping at night
• Logistics and Implementation
Las Delicias, El Salvador




              Las Delicias
 Las Delicias, El Salvador
• Community Facts                                   Project History
   –   ~600 homes, 2700 residents                   • Project FIAT and FIMRC have been active
   –   15 miles NW of San Salvador                  in Las Delicias for > 5 years
   –   On Western Slopes of Volcan San Salvador     • Initial Contact with Project FIAT (Dave H.)
   –   Homes Spread Out, but Las Delicias is               January 2009
       Bordered by Several Similar Communities
                                                    • Application to EWB-USA
   –   Water Storage & Piping System installed 20
       years ago With Water Delivery by Truck              March 2009
   –   Well and Pump Installed < 5 years ago        • Project Approved
   –   Residents are Poor (<$10/week income)               May 2009
   –   Community Well-Organized through Adesco      • Preliminary Assessment Visit
       and NGOs (FIAT & FIMRC)                             July 2009
   –   Able to spend about $5 per household on      • First Assessment Trip
       water each month
                                                           July 2010
                                                    • Second Assessment Trip
                                                           November 2011
Map of Las Delicias Water System




  DOWNHILL
Current Las Delicias Water Supply & Storage System




                          • Pump Runs 6 Hours a day 4
                            days/week  ~ 26 hr/wk.
                          • Pump flow rate: 175-200 GPM.
Map of current Las Delicias Water System
 from ADESCO with approx house locations indicated




           260 Homes Served by Tanque 3




                                           33 Homes
                                                Served
                                                    by Tanque 2
            291 Homes Served by Tanque 1




                 DOWNHILL
Summary of Existing Water System
     Challenges to Las Delicias Water Supply System
•   High electric cost
     – Typical ADESCO revenue from water fee
       ~$2300/mo
     – Typical monthly cost for water system
       ~$2000/mo (mostly electicity ~$1500/mo)
     – Pumps run about 26 hr/wk
     – Not taking advantage of nightime off-peak
       rates
     – Power factor on pumps leads to monthly
       fine of $50/month.
•   Inequitable water distribution
     – Some homes report receiving water
       <1x/week and low flowrates
     – “Valvulero” controls distribution via valves
       to zones (“Tramo”) throughout community
     – Large number of new homes at low
       elevation
• Culture of scarcity where residents hoard
  water when it is flowing
• Water Quality:
     – Effectiveness of in-line chlorination is not
       clear
                Monthly Income for Las

Electric Bill   Delicias ADESCO




                Water System Expenses
    Alternatives Analysis Summary
• Drilling another well ($3500 for hydrogeological study) We
  spoke with a hydrologist in country and drilling a new well
  at higher elevation is considered to have low probability for
  success.
• Solar power for pump (eliminated due to high cost >$50K)
• Additional tank locations (three considered – current
  location on public land and co-located with current tank)
  Other locations require land purchase which could be
  costly and time consuming.
• VFD (variable frequency drive – possibility but must
  consider approx. 10% loss in pump efficiency at lower
  head)
• New pump for better efficiency at lower head.
         Proposed Updates to Las Delicias
                 Water System
•   Objectives
     – Utilize existing and new tank at intermediate elevation to supply water to
       lower half of Las Delicias with lower pumping head required.
     – With new pump (or VFD on existing) and supply line  reduced electricity
       costs due to lower head will result in more water for the community.
     – Improved distribution system  more equitable water supply to all homes
       (especially at lower elevations)
•   Phase I (May 2012)
     – New Water Tank at Intermediate Elevation
     – New Supply pipeline and distribution pipeline
•   Phase II (Fall 2012)
     –   New pump (or VFD added to existing)
     –   Improvements to distribution piping system
     –   Improving power factor for pump via capacitors to eliminate penalty.
     –   Enabling pumping during nighttime to take advantage of lower rates by adding
         a timer circuit to the pump controller. (approx. 20% savings)
Proposed Water Distribution System


                         117 Homes Served
                            by Tanque 3

  280 Homes Served
    by New Tank                         33 Homes
                                             Served
                                                 by Tanque 2



                              154 Homes Served by Tanque 1


                     DOWNHILL
Modified water system
        Summary of potential changes in
           water distribution system
CURRENT SYSTEM                   PROPOSED MODIFICATION
• Storage                        •   Storage
   – Tanque 1: 35,000 gal             –   Tanque 1: 35,000 gal
   – Tanque 2: 11,000 gal             –   Tanque 2: 11,000 gal
                                      –   Tanque 3: 25,000 gal
   – Tanque 3: 25,000 gal
                                      –   New Tank (combination): 28,600 gal
• Pump supplies water to         •   Current 65 HP Pump supplies water
  Tanques 1 & 3 at 175 gpm,          to Tanques 1 & 3 at 175 gpm
  ~4 days per week               •   New 20 HP pump will supplywater
• Spring supplies water to           to new tank at 175 gpm with much
  Tanque 2 (and other tanques)       lower head and energy savings.
                                 •   Homes serviced by Tanques
• Homes serviced by Tanques           1. 154
   1.    291                          2. 33
   2.    33                           3. 117
   3.    260                          New: 280

 New tank reduces demand of water from Tanques 1&2
 (which require high head) by roughly 50%
               DOWNHILL

                                                     Exisiting
                                                      11,000
                                                    gallon tank




Map of Current Water System
 (section relevant for EWB-MAP modifications)
RED lines – supply lines to tank (uphill by pump)
    BLUE lines – distributions lines by gravity
                                                                                                    A




                F




                                                                                               E1
                 NEW LINE




                                                                                           LIN
                    DIS 2a




                                                                                          PLY
                       TRI




                                                                                     D




                                                                        LINE UTION
                           BUT




                                                                                         SUP
                                                                         TRIB W
                              I




                                                                             2b
                           ON




                                                                           NE
                                      NEW




                                                                                     NEW
                                  E         DIS
                                                  TRIB




                                                                        DIS
                                                      UTI
                                                            ON
                                                                 LINE
                                                                        2c                                     DOWNHILL
                                                                             B
                                                                                                        NEW
                                                                                                C       TANK



Proposed update to Water System
 (section relevant for EWB-MAP modifications)
RED lines – supply lines to tank (uphill by pump)
    BLUE lines – distributions lines by gravity
New Tank Design – Location and
   Coupling with Old Tank
Design of New Tank – 3D view of
   Block/Rebar construction
                      Tank Design
            response to J. Knight concerns
• Concrete block vs poured concrete. Block recommended
  by local Structural Engineer (Daniel Rivera).
• Assumed strength of concrete (2000-3000 psi acceptable –
  steel strength controls) Local Engineer accepted 3000 psi
  concrete although 2000 psi concrete will work as well.
• Tank seal at base of wall – We will look into this in further
  detail and will add it if necessary. We will contact seal
  manufacturer and seek advice of a water engineer before
  making a decision.
• Supply pipes will be connected to both tanks with shutoff
  valve to each.
 Design of Additional Pipelines for
                                                                                                    A
 - supplying water to tank
 - distributing water
                F




                                                                                               E1
                 NEW LINE




                                                                                           LIN
                    DIS 2a




                                                                                          PLY
                       TRI




                                                                                     D




                                                                        LINE UTION
                           BUT




                                                                                         SUP
                                                                         TRIB W
                              I




                                                                             2b
                           ON




                                                                           NE
                                      NEW




                                                                                     NEW
                                  E         DIS
                                                  TRIB




                                                                        DIS
                                                      UTI
                                                            ON
                                                                 LINE
                                                                        2c                                     DOWNHILL
                                                                             B
                                                                                                        NEW
                                                                                                C       TANK



Proposed update to Water System
 (section relevant for EWB-MAP modifications)
RED lines – supply lines to tank (uphill by pump)
    BLUE lines – distributions lines by gravity
           Road
                               Supply Pipe 1 Pipe Profile                    Road
                                                                                                     NEW
                                                                                                     TANK
          Crossing
                                                                            Crossing
                                                                                                      C
                                                                                                   655 m
                                                                               B
                                                                                   651 m


                      Elevation:                     D                                     105 m
                      640 m                     643 m
            A                       240 m                         640 m
                638 m


  Tee     Gate        45°             Tee with Manual     Tee with Manual      90°                  90° Pipe
connect   Valve      Elbow            Air release valve     drain valve      Elbow                 Elbow Exit
 to 6”                                                                        with                 Gate   90°
  pipe                                         PIPE FITTINGS                 anchor                Valve Elbow
          Estimate of head losses in
         supply pipe 1 (smooth PVC)




4” PVC sufficient to keep major and minor losses to <10% of the
elevation change
              Supply Pipe 1 Trenching
• Based on recommendations from EWB Water Resource Guidelines
  and advice from Tony Sauder:
   – 70 cm trench depth (45 cm depth acceptable except in road crossing) with
     pipe buried below 50 cm
   – 10 cm bedding (2-12 mm soil) if stones/rocks present in trench
   – Back-fill with soil that is free of lumps, from stones (>3 cm), and from organic
     matter
   – PVC pipe joined in trench and cure for >10 hr prior to pressurizing. Keep joints
     exposed to check for leaks. Expansion joints not necessary
   – For road crossing, may bury PVC pipe inside steel or concrete pipe (ID >
     diameter of PVC joints); final decision to be made in the field after evaluating
     potential for erosion




                                   50 cm

                                                     70 cm
                   10 cm                             trench depth
                                           10 cm
                                           bedding
                                    Valve
                                    Boxes


• Design options
   – Obtain pre-cast valve boxes with lockable lids
     locally
   – Build from bricks and mortar with metal lids

• Specifications
   –   4” Pipe centered about 55 cm below ground level
   –   Box should extend 10 cm above ground level
   –   Internal dimensions roughly 45cmx45cm
   –   Place support under valve
             Photos of current valve boxes installed in Las Delicias
          Valve Box Design




Drawing of valve boxes to be constructed at Las Delicias
     Thrust Anchors for
       Elbows &Tees




From Russ Turner, Tetratech
Summary of May 2012 Implementation
         Keys to Success:
• Success assured by working closely with:
   – Local community providing excavating equipment, funds, land
     and labor.
   – Local Rotary Club and Structural Engineer Daniel Rivera
     providing funds, logistics and expertise.
   – NGO – Project FIAT helping with funds, logistics and volunteers
     as well as arranging for a cement mixer. FIAT has vast
     experience doing these types of projects in El Salvador.
   – The Honorary Consul of El Salvador in Philadelphia is working
     with one of our members (Paolo) to help coordinate the project
     with the local Mayors office. She has also informed us that she
     will arrange to allow us to ship components (such as pumps) to
     the country tax and duty free.
   – NGO - FIMRC providing local health related services to the
     community and EWB by helping us define objectives and
     measure results.
              Summary of Finances for
                 Implementation
•  Local community provides excavation equipment, land, material
   transportation and field labor (assume avg. 4 people, 8 hrs/day for
   duration of project)
• Chapter currently has about $28,500 available for this project including.
    – $15,000 Rotary Grant (must be used by September – specifically ear-
       marked for tank)
    – $8,000 from Project FIAT
    – $5,500 in chapter funds
 • Costs are estimated at about $27,000 including:
    – Tank estimate - $12,500
    – Piping estimate - $10,500
    – Transportation estimate $4,000
    – We plan to raise additional funds to cover gap costs between now
         and May. We will delay piping if funds prohibit completion until the
         Fall.
 Logistics and Implementation Plan
• Engineer – Daniel Rivera of Local Rotary in San Salvador will
  coordinate with local government, obtain building permit, help
  organize material delivery and oversee installation through periodic
  visits.
• Project FIAT volunteers will coordinate with local community,
  organize material deliveries, hire an albañil, provide secure space
  for materials, provide cement mixer, supply working volunteers and
  provide lodging and transportation for EWB volunteers.
• Local community will provide land, excavating equipment and labor
  as well as help in transporting materials to site.
• EWB volunteers will provide supervision, project management and
  labor. EWB volunteers will cover entire 5 week installation.
Schedule for Implementation
     Contingency Plans (worst case
     scenarios) for Implementation
• Project can proceed even if EWB members are
  not present every day.
• Control runoff and use tarps if heavy rains
  become problematic.
             Material Procurement
• Project Fiat has executed many similar projects. They know exactly
  where the type of materials used on this project can be obtained
  locally. Project FIAT will provide a locked building close to the tank
  site where materials can be securely stored.
• All material will be sourced locally. All materials are common
  everyday building materials.
• Daniel Rivera has reviewed the material list and did not have any
  issues with our selections. (He did recommend using grade 40
  rebar instead of 60 and we followed his recommendation)
• The area near the village includes heavy industry and business
  enterprise and the community is only 15 miles from a major city.
  We foresee no major issues sourcing materials.
   Plans for Phase II Implementation
               (Fall 2012)
• Install new pump (or VFD)
• Install Power Factor Correction Capacitors
• Install Timer Circuit to allow Night time
  Operation
• Install additional distribution pipes.
                   Metrics
• Increase water supply by ~40% without
  increasing operating cost
• Increase in % of homes receiving sufficient
  water (at least 2x per week)
             Concluding Remarks
• Project is sustainable through community involvement and
  use of:
   – Locally available materials
   – Standard construction techniques typical to the area.
   – Adding to existing water system infrastructure using
     identical technologies. O&M will be the same as they are
     doing now.
   – The community already has people in place to operate and
     maintain the water system.
• Community will benefit through better distribution and more
  abundant supply with no increase in operating cost.

				
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