VOLUME 89 I 2ND QUARTER 2019
DRINKING WATER (PART 2)
Via lime filters calcium carbonate is dissolved in the water, making it slightly ‘harder’. For dishwasher users: the water has a total hardness of around 50 mg/l or 2.8 German Hardness degrees. With this, the water is still relatively soft and will give little calcification. On Bonaire no fluoride is added to drinking water. Fluoridation is not a legal requirement anymore in Dutch legislation since 1973. After its treatment the drinking water is stored in the tanks of the water plant at Hato. It is then pumped to the distribution tanks on Seru Largu, Sabadeco and Subi Rincon. From there it runs through the water supply network to your main valve. With the distribution tanks standing on hills, gravity ensures sufficient water pressure. Quality Safety is an important aspect for the drinking water supply for the inhabitants and visitors of Bonaire. WEB has its own laboratory that checks the quality of the drinking water. The laboratory takes twice a week samples at the storage tanks at Hato and the distribution tanks at Seru Largu, Sabadeco and Subi Rincon. Spread across the island WEB has installed 34 sampling points in the water supply system. These points are sampled twice weekly. The WEB laboratory tests the water’s chemical composition, color, turbidity, bacteria and taste. If any abnormalities are found in the quality of the water, WEB takes measures and rinses a duct on the spot if necessary. Legionella has WEB’s special attention in the care for safe drinking water. Information about legionella, our approach and prevention can be found our website www.webbonaire.com. Projects Bonaire’s population is growing and tourism is an important economic pillar. Drinking water is one of the basic needs of man. WEB continues to invest in the water supply system so that the reliable supply is guaranteed to all households and bulk consumers on our island. Start independent drinking water production On October 27, 2015 a new desalination unit has been put into operation at the water plant at Hato. With this unit WEB produces 1,600 m3 of drinking water under own management. This brings the total production capacity on Bonaire at 5,600 m3 per day. The production of 4,000 m3 per day by partner GE Water & Process Technology will gradually be brought under WEB’s own management. From 2019 onwards WEB will independently produce drinking water. New pressure pipeline Due to population growth and increasing economic activity the demand for drinking water on Bonaire is rising. To meet this, WEB increases the water storage and transport capacity. More water needs to be transported from the water plant to the storage tanks on Seru Largu. With the current installation this causes too high energy costs in relation to the price of drinking water. Therefore a new pressure pipeline with a larger diameter (from DN200 to DN250) has been constructed. In addition frequency converters (VFD) have been installed on the electric motors of the pumps. These measures considerably reduce energy consumption and increase the efficiency and reliability of the drinking water supply on Bonaire.