TWEED SHIRE Council has managed to reduce the salt concentration of the Tweed drinking water supply overnight, however, water restrictions will remain in place for four to five days as not enough ‘good’ quality water has been produced.
In a media release Council said the salty water situation at Bray Park Weir is now under control, however, residents are asked to continue to minimise water use as it will take another four to five days for the situation to return to normal.
Council has been pumping ‘good’ water from the top of the dam to avoid salty water from the bottom levels and the amount of total dissolved solids in the treated supply has fell to within the ‘good’ range.
Good quality water is now being produced at a rate of 440 litres a second water with a dissolved solids concentration of 279mg/litre.
Normal operations produce water at 160mg/litre and Australian Drinking Guidelines state that anything below 600mg/litre is ‘good’ quality.
“Every hour we can produce 15 megalitres of good water so we will be in a position shortly to recharge the shire’s reservoirs without the risk of pushing more salt into the system,” Manager Water and Wastewater Anthony Burnham said. “We need 20 megalitres a day to meet demand.
“Gold Coast City Council also has very generously allowed us to open the connection between Coolangatta and Tweed Heads and we are receiving 31 litres a second of quality water from them, equating to about 2.7 megalitres a day.
“We should be in a position to close that connection by mid-morning tomorrow.”
Council will continue to release 90 megalitres a day from Clarrie Hall Dam for the next few days to continue to top up the good supplies in the top strata of the weir pool as the dredge works to draw the heavier salty water from depths of about 8.5 metres and discharge it downstream.
“The dissolved solids concentration at the bottom depths has been measured at 3700mg/litre so we are very appreciative of the huge effort of our staff and the assistance of external agencies, contractors and the Gold Coast City Council who have worked to control this situation.”
The Australian Drinking Guidelines advise that the current salt levels are not harmful to human health. However, residents are advised to use bottled water for drinking if the taste of the water is too unpalatable.
The water at Uki and Tyalgum is not affected and no restrictions apply in those villages.