Posted by Brian Shove
Shallow trench ground water supply under construction (2011). Water is fresh but non-potable
Bruce Hart, Ted Lees and Brian Shove will travel to Vava’u on the 5th of August 2019 until the 13th August 2019. The Rotary Club of Papakura Inc is experienced with carrying out project work in Tonga having completed numerous water supply systems over the last 16 years.
Talehau Village is on the Island of Vava’u in Tonga. It has approximately 40 houses and around 120 residents. There is a four room primary school, a Church and a community hall. Many houses have roof water tanks for drinking.
The water system was intended to supply water for washing, cleaning, stock water and irrigation. It is not for human drinking water. The Club installed a shallow ground water pumping system and reticulation pipes over a period from 2010 to 2013. This is an 80m long 1.5 metre deep trench to collect ground water. The trench leads to a sump which has a solar pump and a backup  230 volt mains powered pump which pump to an elevated tank and the reticulates to the village through PVC pipes. The existing solar water pump has 2 solar panels and is rated at 1200 litres per hour. The existing solar pump is a surface pump and requires reliable priming and is rated for low sediment water. At present the solar pump has failed three times over the last 8 years with three replacements needed.
With the villagers will help, the group will replace and repipe the existing solar pump with a new submersible shallow water pump and install 3 solar panels. The solar panels will be reused from a previous project at Pangaimotu, which are redundant after a Japanese funded upgrade. This system is rated for 1300 litres per hour and will deliver 12000 litres per day in summer months. Being submersed, it is self-priming and is rated for water with sediment.
They will also connect the primary school two stall toilet block to the village reticulation system so that the hand washing taps and two toilets have flushing water. This toilet block has an existing operational septic tank. The Club built this toilet block several years ago. At the same time we will carry out repairs and maintenance to spouting, taps and pipe leaks and repair a solar pump at Utungaki we installed three years ago which has a detached impellor.
All materials and equipment needed will be shipped over by Fe’Ofa’Aki Shipping Services who we have used before.
Existing pump shed - roof will be rebuilt to accomodate 3 solar panels and the structure will be strengthened for cyclones
Once the project is complete, the village water supply will keep up with demand. The existing solar pump will be upgraded with a more reliable and pump and the school will have reliable water for the toilet block.
Project Costs $17,000.00
Rotary Club of Rotary Inc
$  6000.00
Foundation Grant
$  2600.00
Talehau Grant
$  3400.00
Harold Thomas Trust
$  5000.00
The lower 230 volt mains powered pump will be retained; the upper solar pump will be replaced with a submersible solar pump located inside the sump