1. PWWA Conference NRW Project – Salelologa, Savaii Progress Presentation
Seugamaalii Jammie Saena, SWA Managing Director
Carlos Mustoni, WLPM Director
Tonga, August xxth 2016

2. Introduction
Project area water source based in the Palauli Faleata District consisting of 3 villages unmetered since system was built more than a decade ago
There was a need to look at the consumption
Provide evidence of the amount of water utilised by these villages
Evidence used to argue the case with the District and Government that metering was necessary
The was a need to extend the coverage area of the source so we could shut down our borehole supplies further down the line.

3. Original Condition

4. First steps

5. First steps: PRV assessment and repair
PRV pressures reduced from 86 to 43m
Faleata WTP Daily Flow reduced from 9,304 to 7,456m3 (-20%)

6. First steps: Palaluli villages consumption
FMs were installed in all the villages submains.
Villages consumption assessed: it represents 44% of Faleata WTP daily flow

7. Some delays…but keep working
A storm burned out two bore pumps. The IVs were opened until July 2013.
System returned to previous configuration (Puapua, Lano, Sapapalii and Lalomalava bores working through a floating valve)
Loggers purchased and installed. High pressures in all the North area. Pumping hours started to be reduced to 12hours and later 10h/day.

8. PRV relocation
The pressure upstream was 140m and the pressure downstream was set at 89m. It impact in the whole area, from Faleata up to Iva.

9. PRV relocation impact
The reduction since July 2012 was +/- 4,170m3/day, 45% of the WTP original flow.
Status
MNF (12 to 4am, l/s)
Daily production (m3)
Reduction (%)
Original (13-20/7/12)(1) 83
9,304 -
Tafua PRV (20-27/7/12) 72
7,456 20
Tafua PRV adj (28/3/14) 60
6,372
14.6
Faleata PRV (3/6/14)
48.5
5,134
19.5

10. Faleata new supply area: from Iva to Lalomalava

11. Faleata 2nd extension until Tuasivi

12. Works and impacts
All the extensions demanded big operational and improvement works (new valves, interconnections, service connections improvement, etc.)
New PRVs were installed at Tafua and Wharf to reduce the leaks on the area and to allow the extension of the area supplied by Faleata.
Lalomalava and Sapapali bores were stopped. Just two bores remain in use: Puapua (8h/day) and Lano activated with a floating valve.

13. Tafua and Wharf PRV impact
PRV reduced to 30m (Ups 50m)
flow reduced from 187m3/d to 100m3/d, representing a 46%.
Wharf
flow reduced from 900m3/day, to 648 and finally to 500m3/day, representing a saving of 44%.

14. Palauli Villages
New FMs were installed in all the villages submain as they started to be blocked.
The relocation of the PRV had an impact in their daily flow but each one has different extension and CPP, so it was decided to install PRVs in each submain and conduct an individual pressure reduction in each area.
All the customers at all the villages started to be metered.
The actual supply of 995m3/day represents a reduction of 70% since July 2013.
Palauli villages supply represents now 18% of Faleata production (in 2013 it was 50%).
Village
Average 29/6-13/7/13
Average 20-21/10/15
Average 21-22/10/15
Average 1-2/3/16
WTP Submain
235
108
102
103
Maorist
526
114 94 88
Vailoa 3
120 44 31 35
Vailoa 4
323
173
137 87
Vailoa 5 45 32 22
Vaitoomuli 1
186 89 90 58
Vaitoomuli 2
941
430
345
255
Vaitoomuli 3
126 69 59 53
Faala 1
231 55 49 47
Faala 2
263
128 80
Faala 3
324
217
181
167
Total
3,310
1,472
1,234
995

15. Faleata supply area last extension(until Faga)

16. Faleata 1st Water Balance
The water supply to all the customers (outside Palauli, Tafua, Wharf, and Salelavalu) from Faleata until Sapapalii is 2,358m3/day. It represents 43% of the water produced by Faleata.

17. Following steps
Assign the customers from each village to the water supply areas to allow a better NRW study and to identify areas with higher leaks.
Replace the existing old PRV at Faleata for a timer PRV to be set in three different downstream pressures:
80m to cover morning and evening peak hours
60m from 10am to 5pm
45m from 10pm to 6am to cover night
low consumption

18. Conclusion
All villages within this district now metered and billed Success of these works show the importance of pressure management, leak detection, capacity building of staff, political buying and public consultation no matter how unwelcome and unpopular your works are perceived