Our water supply areas

This data has been taken directly from our telemetry system, and has not been checked for accuracy by a human. Although we strive to maintain our telemetry system in good working order, occasional power outages, sensor failures and glitches may interfere with results.

Due to the sensitivity of the water supply in Nimbin, we have to skip Level 1 Restrictions in Nimbin. Level 2 Water Restriction are brought in at 87% or when otherwise required.

The water restriction levels in this plot are indicative only. Sometimes, water restrictions may need to be brought forward or delayed due to a variety of reasons including weather forecasts, water demand or keeping restrictions consistent across the Northern Rivers. 

D. E. Williams Dam has a spillway, which helps maintain water quality by letting old water spill out of the dam. The dam starts to spill at about 97%, so you will probably never see it reach 100% capacity.

Ironically, too much rain can cause the dam to lose water. The dam can only gain water when we pipe water into it from the weir or when rain lands directly on it. When we have heavy rain, all of the runoff in the catchment for Mulgum Creek can make the water in the creek too dirty for us to put it in the dam. Until the creek clears up again, the only water that enters the dam is the rain that falls on it. Because of this, you will often see a spike in dam level during heavy rain, followed by a slow fall and rise over the following days or weeks.

Lismore is supplied with water from Rocky Creek Dam, which is managed by Rous County Council. For more information on Rocky Creek Dam, please visit Rous County Council’s website.

The Mulgum Creek Weir is essentially a miniature dam built across Mulgum Creek, and is the source of Nimbin’s water supply. The weir holds back enough water for us to keep Nimbin supplied, and then lets the rest flow over it and continue down the creek. Depending on the weather, the flow that spills over the weir can be anything from a roaring waterfall to a tiny trickle. In drought conditions where there is very little water in the creek, the overflow can completely stop. So long as the weir is overflowing, there is enough water in Mulgum Creek to keep Nimbin supplied with some left over for the environment.