Our water supply areas

Overview

Lismore City Council provides drinking water in the following areas:

  • Lismore
  • Nimbin
  • Caniaba
  • Dunoon
  • The Channon
  • Modanville
  • Tullera
  • Clunes
  • North Woodburn

Most of our drinking water is supplied by Rous County Council, who treat water from Rocky Creek Dam at their Nightcap Water Treatment Plant. Some places like Richmond Hill are even supplied with their drinking water directly from Rous County Council. However, the drinking water in Nimbin is managed entirely by Lismore City Council.

For more information on Rocky Creek Dam and Rous County Council’s water treatment processes, please visit their website.

Nimbin water supply

Water in Nimbin is extracted from Mulgum Creek via the Mulgum Creek Weir, and then is chlorinated to kill harmful viruses and bacteria.

Chlorinated water is then piped to the D. E. Williams Dam for storage. Nimbin Rural customers also receive their water from this pipe. The D. E. Williams Dam holds about 25 million litres of water, which can keep the village of Nimbin supplied for at least 2 months.

When the village of Nimbin needs drinking water, it is extracted from the D. E. Williams Dam, filtered by the Nimbin Temporary Water Treatment Plant, topped up with chlorine and then pumped up to the Nimbin High St Reservoir for distribution.

D. E. Williams Dam level

To help keep the Nimbin community informed on water availability in the D. E. Williams Dam, we have compiled the following information. We’ve also included some FAQs to help with interpreting this data.

D.-E.-Williams-Dam-Level-05-11-2024.png

How accurate is this data?

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.

What happened to Level 1 Water Restrictions?

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.

This plot doesn’t match up with our current water restrictions – what’s going on?

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. 

 

Why doesn’t the dam ever reach 100%?

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.

We’ve had a lot of wet weather recently – why is the dam level going down?

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.

What about the dam level for Lismore?

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.

Chlorination of drinking water in Nimbin

We use sodium hypochlorite to add low levels (less than 5 parts per million) of chlorine to the drinking water in Nimbin. These levels are harmless to humans, but very effective at killing harmful viruses and bacteria. This helps prevent diseases from spreading through our drinking water, keeping everyone safe, happy and healthy.

For more information on other treatment processes used on water in our Rous County Council supplied areas, including fluoridation, please refer to Rous County Council’s website.