Lessons of the Millennium Drought

Australian water management experts attending an event in São Paulo shared solutions developed to address 1997-2009 drought.

By Karina Toledo

Agência FAPESP – Australians have long been accustomed to periods of drought alternating with torrential rain and floods, but at the end of the twentieth century they were taken by surprise by the Millennium Drought, a dry period of unprecedented length and severity that affected the entire country between 1997 and 2009 and was particularly devastating to the inhabitants of Melbourne, the state capital of Victoria.

“The Millennium Drought was completely different from what could have been foreseen based on an analysis of over 100 years of meteorological data. When it finally ended, we had floods in several cities and severe heat waves. No fewer than 123 rainfall and temperature records were broken in the summer of 2012-13. In the following year, 156 records were broken,” said Tony Wong, Chief Executive Officer of the Cooperative Research Center for Water-Sensitive Cities, an initiative of the Australian government that brings together researchers in several fields and institutions, as well as industry and government partners, to develop social and technological urban water management solutions.

Inflows to the reservoirs from which Melbourne draws its water supply were severely affected by the drought. In 2008, the level of the region’s main reservoir on the Thomson River was similar to the current status of São Paulo’s Cantareira System. Although the level of Thomson Reservoir improved in later years, it never returned to its historical average and has recently fallen again.

“There came a time when we were extremely alarmed because the amount of water was sufficient for only 18 months of supply,” Wong said. “That’s when we decided to build a desalination plant.”

During an event held in São Paulo on April 22 with FAPESP’s participation, Wong said the Millennium Drought taught Australians two important lessons. First, in the context of climate change, which brings extreme weather events in its wake, the management of a city’s water resources cannot be based solely on analyses of historical meteorological and water flow data.

The second lesson was that infrastructure for the future must be planned to account for extreme events in an integrated manner. In other words, solutions cannot address phenomena such as droughts and floods in isolation.

Wong came to São Paulo with the Victorian Education Mission to Latin America, which was organized by one of Australia’s most important states to promote academic collaboration in education, water management, urban planning, agriculture and biotechnology, among other areas (read more at: http://agencia.fapesp.br/21181).

Wong recalled that the government of Victoria began taking steps to minimize the impact of water shortages in 2004, when Australian experts were still saying the drought was part of ordinary climate variability. The first step consisted of investment in water conservation strategies.

“A mass campaign was launched to change people’s behavior,” Wong said. “A huge panel was put up in our main train station with alerts that showed reservoir levels falling day by day. That’s when we realized we were facing a water crisis.”

Restrictions on water use were put into place across Australia. The use of drinking water for car washing or in garden hoses was banned, for example.

The campaign to reduce residential water consumption was combined with conservation strategies in agriculture. The implementation of a program to modernize irrigation systems had begun even before the drought, and it helped to increase water use efficiency from 30% to 80% on Australian farms. Another measure was the creation of a water market where farmers could sell water surpluses to others whose crops required more irrigation.

“Consumption per inhabitant in Melbourne began to fall as the community in its entirety got more involved. If it hadn’t been for this change in behavior, our water would have run out completely by 2009. The conservation strategy saved the city. The desalination plant couldn’t be built in time,” Wong said.

Initiatives to increase the use of alternative water sources were implemented in parallel with the conservation measures, including the development of infrastructure to reuse stormwater and wastewater.

“However, approximately in 2007 it became obvious that all of these initiatives take time to be effective and represent real solutions, so the government decided to invest in desalination. The drought ended before the plant was ready. In fact, it hasn’t yet produced any water for Melbourne, but this infrastructure gives us the certainty that we won’t run out of water if there’s another drought. Meanwhile, we have breathing space to invest in more sustainable long-term solutions like water recycling and reclamation,” Wong said.
 

Diversity of sources

Another important lesson learned from the Millennium Drought, according to Wong, was the need to diversify the portfolio of water sources and to constantly review strategies as new technologies emerge. Water security for cities can no longer be guaranteed on the sole basis of the traditional reservoir storage model.

“Wastewater is a frequently overlooked resource. We can create decentralized solutions to reuse this water for crop irrigation and toilet flushing, for example. With the right public policy, whenever an old building is demolished, we can ensure that a new one introduces water reuse infrastructure,” Wong said.

Investment in stormwater collection infrastructure can also help solve the flooding problem, according to Wong.

“In Melbourne, we’re harvesting stormwater runoff in large storage basins so that we can avoid inundation in flood-prone areas,” he said. “With weather radar monitoring, we can predict the arrival of a storm and drain the detention basins in time.”

Wong advocates the use of mathematical models to simulate scenarios and to evaluate the impact of public policy measures before they are implemented, given the impossibility of relying on historical data to predict future conditions, because the science shows that stationarity can no longer be assumed.

“In the future, our water management infrastructure will have to be a combination of centralized solutions – large-scale initiatives implemented by government – and decentralized solutions implemented by local communities with public policy incentives,” he said. “Decentralized solutions will give cities the resilience to survive in the context of climate uncertainty.”

In addition to Wong, the Victorian Education Mission included 28 other high-level representatives of universities and research institutions, as well as senior government officials. It visited Chile, Brazil, Colombia and Peru from April 20-29.

“Many Latin American cities share similar challenges to Australia and the state of Victoria. These shared experiences highlight areas of mutual interest and possible alliances between our governments, researchers and education experts,” said Steven Herbert, Victoria’s Minister for Training & Skills, who led the mission.

Sheila Lunter, Australian consul and trade commissioner in São Paulo, said Australians are familiar with the problem of water shortages and want to share their experiences with the people of São Paulo State.

“São Paulo is facing a grave water crisis owing to low storage reservoir levels,” she said. “We hope that by sharing the lessons we’ve learned that we can help identify innovative solutions to address the climate change that we’re all going to face in future.”

FAPESP was represented at the event by Fernando Menezes, Adviser to the President; Sergio Robles Reis de Queiroz, Assistant Coordinator of Research for Innovation and of the Master Plan for Science, Technology & Innovation in São Paulo State; and Reynaldo Luiz Victoria, Coordinator of FAPESP’s Global Climate Change Research Program (PFPMCG).

Professor Américo Sampaio, Sanitation Coordinator of the São Paulo State Department of Sanitation & Water Resources, spoke about the water crisis currently faced by the state and the strategies that are being implemented to enhance water security in the region.

“Desalination of seawater is not part of our current plans because it’s too expensive,” he said. “Our top priority is effective water management by matching demand, which includes measures to reduce consumption, with supply, which includes bringing water in from more distant catchments.”

Sampaio cited as examples of supply management the emergency projects as well as medium- and long-term infrastructure improvements that are now being implemented by the state government, including the diversion of the Paraíba do Sul River.

In demand management, Sampaio said the state government plans to encourage apartment buildings to install water meters in each dwelling unit as well as water reuse equipment. Residential consumers are being urged to install water-efficient faucets, showerheads and lavatory equipment. He also said that the control of water system loss must be greatly enhanced and that prices should be reviewed. Water is too cheap at the moment, he argued.