Floods are becoming more common. Storms in winter 2015 have caused devastating floods across large areas of the UK, including Yorkshire. Millions of pounds of damage have been caused to infrastructure and homes. Flood events can also be detrimental to river ecology and can increase the delivery of pollutants to the channel.

There are several reasons for the increased frequency and magnitude of flooding and the exact causes of flood events are difficult to determine. There is an increasing body of evidence to suggest that extreme daily rainfall rates are becoming more intense as a result of climatic warming.

Changes to the way we manage the landscape is also contributing by reducing the amount of water stored in the catchment and causing water to be delivered to the channel more rapidly. These changes include deforestation, moorland drainage and soil compaction.

Further, half the houses built in Britain in the last 60 years have been on floodplains. This has increased our vulnerability to flooding.

With a greater magnitude of flood events flood defenses are under increasing pressure and there is an increasing focus on the use of natural flood management techniques to contribute to reducing flood waters. See our Guide to Natural Flood Management techniques.


Flood water in York in December 2015.

The Telegraph 07/01/16


Droughts are usually a result of long periods of below average rainfall but can be made worse by abstraction and land use change. Areas of Yorkshire were declared as under drought conditions in spring 2012. Drought can cause significant problems for wildlife as well as limiting human uses of water. The low flows also reduce the capacity of the river to dilute pollutants.

Changes to catchment land use, such as urbanisation and moorland drainage, can result in water been delivered rapidly to the channel. As well as increasing flood risk, this means that there is less water stored in the catchment, in ground water and aquifers, to buffer against drought conditions.

Abstraction is the removal of water from the rivers, lakes, wetlands or reservoirs. Water is abstracted to meet a wide range of uses including drinking water, industry and agriculture. The effect abstraction has on the environment depends on the amount and timing of the abstraction. The Environment Agency have a licensing system to control abstraction and aim to ensure sustainable supplies of water for the public, businesses and agriculture, while making sure rivers and other wetlands support a good ecology.

Grimwith Reservior near Hebden in drought conditions.

© Copyright Stephen Craven