Why the Tap Got Tighter: West Australia's Water Restrictions - A Story of Survival

The history of water management in Western Australia is a fascinating journey of survival and innovation. It’s a story about moving from simple reliance on rain to complex, engineered solutions to secure our future.

This post explains the forces that led to our Permanent Water Efficiency Measures (like the sprinkler rosters) and why they are essential today.

The Problem: A Drying South-West and Growing Demand

For over a hundred years, Perth and surrounding towns got most of their water from huge dams. These dams relied on rainfall and streamflow from the hills. But two major things changed that:

1. A Significant Change in Climate: Starting in the 1970s, the south-west corner of WA began experiencing a long-term reduction in rainfall. This wasn't a temporary dry spell; it meant far less water flowed into the dams, a trend that has continued for decades.

2. Population Boom: While the natural source of water was shrinking, the cities—especially Perth—were growing fast. More people meant more homes, more gardens, and ever-increasing demand.

The unavoidable challenge became clear: the amount of water coming in was not enough to meet the amount going out.

The Turning Point: Moving Beyond Rainfall

The need for action became critical in the early 2000s after record-dry years. It was clear that water supply could no longer depend on inconsistent rainfall. The state committed to a two-part solution: building new, rainfall-independent sources and enforcing permanent conservation.

1. Engineering New Supply

Today, our water supply is a mix. While we still use water from dams and natural aquifers, the majority now comes from new sources:

• Desalination Plants: These were the biggest game-changer.

  • The first plant opened in 2006 (Kwinana).

  • The second plant opened around 2011 (Binningup).

  • These facilities turn ocean water into drinking water, providing a reliable, drought-proof supply.

    
    

• Groundwater Replenishment: This innovative system treats recycled wastewater to a very high standard, then injects it deep into underground aquifers to boost our groundwater reserves. The first stage of this scheme became operational around 2017.

2. Enforcing Permanent Conservation

Even with new water sources, conservation is crucial. This is why the restrictions became the Permanent Water Efficiency Measures (PWEMs), in effect from 2007 onward:

Rule	Start Date	Why It Matters
Two-Day Sprinkler Roster	From 2007	Limits garden watering to just two days per week (based on your house number) to save millions of litres and manage demand.
Winter Sprinkler Switch-off	From 2010	Bans all sprinkler use between June 1st and August 31st. Winter rain is enough for your lawn, saving billions of litres for the drier months.
Bore Water Roster Alignment	From 2022	Cut the watering days for private bore users to align with scheme water users. This was necessary to protect our precious, shared groundwater.

The Bottom Line: Your Part in the Future

The water restrictions aren't temporary inconveniences; they are a vital, non-negotiable part of securing Western Australia's water future for everyone. They are an essential tool for managing a growing population with a different, and much drier, climate.

To be a water-wise resident and do your part, you need to know your specific watering days and times. Click here to find the official watering days for your home: 

Watering Days