MidCoast Council had an emergency plan in place and on Boxing Day it ran a trial water run from the Tea Gardens / Hawks Nest aquifer to the tower on Cemetery Road to make sure everything was in place if the river flow dropped below the required amount.

According to council's director of infrastructure and engineering services, Rob Scott, so long as the flow was above three megalitres, Gloucester was okay. On Monday, December 30, council made the decision to start carting in water as the Barrington River ceased to flow.

When looking at the WaterNSW real-time river flow graph captured on December 30, it appeared the river stopped flowing on December 23 at the Forbesdale station near Rocky Crossing. The station closest to council's pump site, Relfs Road had been offline and wasn't showing any data. WaterNSW staff attended both sites on December 30 to get the records back on track.

Once working, the Relfs Road location showed a dismal flow, while the Forbesdale graph had changed completely, indicating water only stopped flowing on January 1. When asked about the data difference, a spokesperson for WaterNSW said the changes are due to an "on-site adjustment" at both gauging stations.

"On-site flow measurements are carried out periodically across the river monitoring network to evaluate the accuracy of the current operational rating table and changes are often made to reflect the changing river environment over time," a spokesperson said.

The measurements taken recently provided a more accurate reading and the information provided online was revised.

For now, and until Gloucester sees a fair bit of rain, council will be carting water to town. From Thursday, there will be a fleet of five water tankers making the four hour returned trip, with three operating on a continuous 24 hours basis and the other two as needed up to 14 hours per day. Council's plan is to make 26 trips per day. Prior to that the trips have been more constant as smaller tankers are being used.

"Trucks can be expected from 30 to 60 minutes apart. We are expecting it to be full speed for carting for the next two weeks," Mr Scott explained. "There are some prospects for rain later this month which might result in some river flow that we can use. We will extract from the Barrington River and reduce carting where we can, however until rainfall occurs we will need to keep carting water to meet demand."

As the usage in Gloucester has been fairly consistent and in line with the level four water restrictions target, council hasn't needed to elevate the town to level five emergency.

"Whilst we haven't gone to level five we have relocated the water carters to using sources other than the Gloucester system and we have also allowed the car wash to operate on 50 per cent of their normal usage, so usage in the Gloucester system is further reduced," Mr Scott said.

"Staying at level four recognises what the community has done to minimise water usage already. We will be waiting to confirm the subsidy arrangement before making a decision on further restrictions."

Council estimates that overall carting is a bit higher than $20 per kilolitre, but the cost is eligible for up to a 90 per cent government subsidy.

"We will be working on the costs of carting and the proportion of the subsidy now that we are starting to get real figures. Over the past few days demand has been around 550kL per day."

The state of Gloucester's town water supply sparked interest on social media with resident, Peter Mclaughlin suggesting council hold a community meeting to update people on what's happening and what the plans are.

Council said updates on water storage have been provided the community conversation meetings, most recently on November 5, and it's one of the top six priorities for the community.

In the update, council spoke about its large investment over the next five to 10 years in water infrastructure, including a multi-million dollar investment into water storage.