Avon Dam was the third and largest of the four dams constructed to collect water from the Illawarra Plateau. Created by damming the Avon River and completed in 1927, Avon Dam’s main role today is to supply water to the Illawarra region. It is Sydney’s second largest dam after Warragamba but has a small catchment.
Water from Nepean Dam and water transferred via Nepean Dam from the Shoalhaven can be sent to Avon to secure water for the Illawarra.
Work on Avon Dam began in 1921 and was completed in 1927. The curved dam wall was built using cyclopean masonry. This consisted of sandstone blocks, quarried from the site, fitted into an irregular pattern and packed with sandstone concrete. The blocks were lifted into place by electric powered cranes.
The rock was quarried to make a deep cut through a ridge to a neighbouring creek to provide the dam’s spillway, which discharges into the Avon River 800 metres downstream.
A 9.6 kilometre road was built from Bargo railway station to transport construction materials. The dam builders lived near the construction site in single-storey barracks for single men. Land was placed at the disposal of the married men who were assisted in constructing temporary houses for themselves and their families.
A tunnel linking Avon and Nepean dams, to enable the transfer of water between dams in either direction, was completed in 1973.
Top 5 things to see and do
1. Be photographed in Egypt!
Stand under one of the massive stone gateways at either end of the dam wall and have your photo taken. Your friends may think you’ve been on holidays in Egypt! The gates were inspired by the popularity of all things Egyptian following the discovery of King Tutenkhamun’s tomb in 1922. Construction of Avon Dam started in 1921 and was completed in 1927.
2. Walk across the dam wall
After your photo under the Egyptian style gateway, walk across the curved wall of the dam. It’s 223 metres to the other end, and you’re 72 metres above the river below. Pause halfway and admire the views of the lake upstream. Look downstream and you’ll see the rockfill embankment built in the 1970s to strengthen the wall.
3. Step back in time
Be on the lookout for reminders of the dam’s glory days as a picnic spot in the 1930s and 1940s, when Upper Nepean dams competed for the most beautiful gardens. Avon Dam retains remnant features that evoke images of an Egyptian revival landscape. As you walk from the dam wall to the viewing area near the spillway, keep an eye out for remnants of fountains and ponds to your left, and an old fernery to your right.
4. Soak up the views
Elevated paths and the dam wall provide excellent views of the lake in its natural bushland setting. Avon Dam draws water from a catchment of 142 square kilometres of mostly protected bushland. Look out for the jagged teeth of the serpentine spillway. The unusual design allows more water to spill from the lake during floods.
5. Relax with a picnic
Relax with family and friends in the landscaped grounds. Throw down a rug and enjoy a picnic – you’re sitting on the site where the dam builders lived. Electric barbeques, drinking water, picnic tables and toilet facilities are located throughout the grounds. There’s a children’s playground at the top picnic ground, and a row of older-style picnic shelters closer to the dam walk and lake.