With Tenterfield Dam now at 36 per cent capacity, the shire water situation is rapidly becoming critical.
Council advises that the good news is that town water usage has dropped from 600,000 to 500,000 litres per day. The bad news is that the potable water from the Water Dispensing Station in the Tenterfield Industrial Estate has risen from 20,000 litres per day in November 2018 to 130,000 litres per day in February 2019.
Discounting the 1,114,000 litres used for the recent fires, a massive 2,521,000 litres was drawn from the station during February. The station was accessed 734 times in the 28 days of February, or 26 times per day.
Council said the trend is clearly on an exponential growth curve and indicates that the Tenterfield reticulated supply is supplying a far wider catchment than it was originally designed for.
Part of the use will be for stock, particularly with lifestyle blocks just outside of the reticulation system area. However, it is suspected that the main issue is that those with household water tanks outside of the Tenterfield reticulation area are using this potable water to sustain their households (washing, drinking, and toilets).
This is creating big problems for council and the community as, historically, Tenterfield doesn’t receive much winter rainfall at the best of times so the volumes being accessed from the Water Dispensing Station may actually increase.
"The usage of potable water from the Water Dispensing Station for stock is unsustainable," Mayor Peter Petty said.
"At the current usage rates the Water Dispensing Station will reduce the water available in the dam by 80 days.
In line with council’s Level 4 water restrictions, water purchased from this facility is subject to council approval and is banned under Level 5 water restrictions.
"Council is in the process of developing a more streamlined method, but in the interim council will be turning off the automatic component of the Water Dispensing Station, with requests to purchase water for domestic use only to be directed to the office."
In better news, the Shirley Park bore is now pumping water into Tenterfield Dam, after a number of physical and technical problems were overcome.
This will top up the dam at a rate of between 600,000 litres and 1,000,000 litres per day.
In addition, a ‘test bore’ located in Apex Park may be turned into a ‘production bore’ subject to all the hydrology, licenses and quantity testing being satisfactory. If this is the case, the bore's water will be made available for stock use.
Council said this setup process may take some time but it hopes to fast-track the approval processes.
"Cost for this bore will be in the vicinity of $60,000, however it will reduce consumption from the potable supply being used for stock," Mayor Peter Petty said.
"It should be noted that this water will not be for human consumption and will come with a disclaimer."
Council will also shortly be engaging a hydrogeologist to assist in locating a new backup potable water bore, given the current water crisis, although it won't be a quick fix option.
“Council has no choice but to act with great conviction, as firstly the long-term rainfall prediction isn’t great, and secondly the Shirley Park bore is somewhat salty and therefore we are limited, as the dam drops, as to how much of this water can be used to top up the dam,”Mr Petty said.
“Once the ‘shandy’ becomes too salty, there is no point in adding bore water as the water filtration plant wasn’t designed to treat salty water.”.
Council is investigating new technologies which will help locate better quality underground aquifers and therefore reduce the risk of capital expenditure on test bores that don’t produce water.
Council will also shortly commence the process of investigating the possibilities and constraints of trucking in potable water from further afield. This has its own challenges of access to the existing Water Treatment Plant,as well as cost.
“We are all in this together," Mr Petty said.
"There is no quick fix, apart from a good downpour.
"But be assured that councillors and council staff are working together to find the best possible outcome for our community.”