On this page: Potential impacts of drought; drought in the Waikato region; drought and the climate; what we are doing; what you can do; useful links
A drought differs from other natural hazards in that it lacks any precise or universally accepted definition, seldom results in structural damage and can linger for lengthy periods of time in affected areas.
A drought is generally defined as a shortage of rainfall over an extended period of time, which restricts or prevents a human activity. This can lead to a reduced volume of water in water bodies such as rivers, dry ground and a lack of plant growth. These impacts affect activities such as agriculture and power generation, and can have flow on effects to other sectors of the community.
Because the main impact of a drought is often on agriculture, the Ministry for Primary Industries (external link) will declare when a dry period is classed as a drought.
Potential impacts of drought
Drought can impact on our environment, economy and society. Water shortage impacts the environment and changes the way rural, urban and commercial sectors can use water. Losses from these sectors then flow through into other areas like retail and power production and can cause price increases.
Water shortage events may:
- affect the productivity of land as well as terrestrial and aquatic habitats (external link)
- have in-stream impacts due to low water flows
- result in short-term vegetation die-off, and lead to the risk of fire
- increase sediment and nutrition run-off following rain
- increase the risk of erosion due to heavy rain following a water shortage
- lead to nitrate poisoning of stock following a dry period and heavy rain.
Economic impacts from water shortage events tend to have a major impact on Waikato’s regional economy through:
- drying out crops and grass so that livestock don’t have enough to eat
- increased prices for supplementary feed
- reduced volumes of primary production
- reduced water flow in storage which can cause problems for the production of hydroelectric power
- pressure on farm cash flows and income
- significant loss of income to the region and the nation.
The social effects of drought can be:
- distress for rural communities, through welfare issues such as stress and loss of income
- water restrictions for rural and urban populations
- famine and malnutrition ( while the potential for this in NEw Zealand is low, in many parts of the world drought is one of the major causes of malnutrition and can lead to significant loss of life).
Drought in the Waikato region
Historically, water shortage and drought within the Waikato region has not been as severe as in other regions of New Zealand, such as Otage, Marlborough, and Hawke's Bay. However, drought events have impacted communities and the Waikato region's economy in the recent past. Areas typically most affected by water shortage and drought ocnditions are the Hauraki Plains, lower Waikato Basin, Thames-Coromandel, and Pukekohe.
Maps of the region's climate can be viewed on the NIWA website (external link) .
Recent examples of drought in the Waikato region include:
- 2007- 2008: A drought event lasted from November 2007 to April 2008, during which the Waikato experienced its driest January in a century. A shortage of feed caused by the drought increased the price of silage to four times its normal rate. The cost of the drought was believed to be $1.5 billion to the Dairy sector alone. The economic effect of the drought was one of the factors that threw New Zealand’s economy into recession by mid 2008.
- 2009: The Waikato experienced a dry spring, the effects of which were compounded by the previous drought of 2007-2008.
- 2010: Waikato had two dry springs, which resulted in a double drought. The drought led to the owners of the Waikato River hydro scheme, Might River Power, announcing a 10 per cent drop in hydro production for the December quarter. Dairy farmers were estimated to have lost an average $100,000- $150,00 in income over the previous three years due to consecutive drought events.
Drought and the climate
Changes in weather patterns can affect the likelihood of drought in our region. Both El Niño (external link) and La Niña (external link) phases of the Southern Oscillation weather pattern can cause droughts around the country, however an El Niño (external link) pattern is more likely to cause droughts in the Waikato region. It has also been predicted that climate change (external link) will increase the frequency, severity and length of droughts.
What we are doing
- Waikato Regional Council has developed a Water Shortage Risk Mitigation Plan which sets out a management scheme to anticipate and cope with periods of water shortage and the associated environmental problems. (external link)
- Waikato Regional Council works closely with other agencies affected by drought, such as the Rural Support Trust, Federated Farmers, and district councils.
- In severe cases, a regional drought committee may be established with representatives from key agencies, including the Ministry for Primary Industries, coming together to work together on how best to minimise the impact of the water shortage or drought.
- Waikato Regional Council's environmental farming systems team assists key agricultural stakeholders and the sector in general to develop, promote and implement farming practices that can help during a drought.
- Civil Defence and Emergency Management works closely with and supports other agencies, such as the Ministry of Social Development and the SPCA, to ensure the welfare of both humans and animals is being cared for.
What you can do
Try to conserve water
Water is a precious resource and should be conserved, not only during times of drought. Councils in the Waikato region are working together to help conserve water with the Smart Water Use campaign, which includes some simple, handy tips on what you can do around your home.
Follow the water restriction levels for your district
Follow the fire restrictions for your area