The NSW SES is urging low-lying households along the Barwon-Darling River around Walgett, Brewarrina and Bourke to prepare to isolate for seven to ten days as authorities expect water levels to rise over the coming weeks.

Floodwaters are not expected to isolate the three townships.

Low lying rural properties and homesteads along the Barwon between Walgett and Bourke may also become isolated.

The Barwon at Brewarrina may reach the minor flood level of 6.40 metres during mid-late next week (18 - 21 December), according to the latest update from the Bureau of Meteorology (BOM) at 12:47pm today.

Four Mile Camping Reserve on Tarrion-Yarrawin Road will close while Barwon River Public Boat Ramp may close.

At Bourke, the Darling River is at 4.67 metres and rising slowly, and may reach around ten metres at the end of December or early January, above the minor flood level of 9.5 metres.

A photo taken near the junction of the Namoi and Barwon rivers in Walgett. IMAGE: supplied

Parkdale Road, Dry Bogan Road at Little Bogan River and North Bourke Recreation Area Public Boat Ramp may close.

Predictions are expected to be refined as the flood peak moves downstream.

The SES is advising residents likely to be isolated to stock up on essentials now.

Meanwhile in Walgett, the river level peaked 10.79 metres at around 6:45am on Tuesday 11 December and is expected to fall below the minor flood level of 10.5 metres during Thursday into Friday.

No major flood impact has been reported in the town.