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Water Pollution

Volume 448: debated on Tuesday 4 July 2006

To ask the Secretary of State for Environment, Food and Rural Affairs what is the cause of the green bloom in the waters of the Hampshire Avon below Amesbury; and what steps are (a) being taken and (b) planned to remedy the problem. (81120)

The cause of the green bloom in the waters of the Hampshire Avon below Amesbury is likely to be a combination of environmental factors, including high temperatures, low water flow and consequential increases in the concentration of nutrients. There have been no significant pollution incidents at this location in the river. Rainfall and river flows have been significantly depressed over the last 20 months and, in combination with other environmental factors, this may create opportunities for algal growth. However, the May 2006 period was characterised by periods of very high rainfall. Urban and agricultural runoff may lead to direct discolouration and also contribute to nutrient enrichment in the river.

There is, and has been, significant investment and action to improve the quality for the Hampshire Avon in recent years.

For example, four Wessex Water sewage treatment works discharging into the River Avon have had phosphate stripping installed in their treatment process as part of the previous environmental programme periodic review. Wessex Water's current water quality environment programme for 2005-10 includes schemes to further reduce nutrient loads from sewage effluent discharges. By the end of the 2010 period, two additional sewage treatment works discharging into the River Avon are expected to receive phosphate stripping and the phosphate limits set for the four original works are expected to be reduced to half of their currently permitted limit.

In addition, as part of the requirement introduced by the habitats directive, the Environment Agency have asked Wessex Water to review their abstractions on the Hampshire Avon and assess their effect on the ecology of the river. The findings from this project, which will conclude by March 2008, will contribute to the Habitats Directive Review of Consents and may result in a requirement to reduce the amount of water abstracted by the water company, or for other improvements to be made in the companies’ water management operations.

Most recently, the Hampshire Avon catchment has been identified as a priority catchment under the England Catchment-Sensitive Farming Delivery Initiative (ECSFDI). The key objective of this initiative is to raise awareness of agricultural pollution and encourage farmers to take action to mitigate the impact of agriculture on the water environment, including the reduction of nutrient inputs.

The water framework directive (WFD) is a key driver of future action on water quality. The directive came into force on 22 December 2000 and requires member states to establish a range of measures to manage water quality by 2009 and to make them operational by 2012. A central objective of the directive is that water bodies should aim to reach good ecological and chemical status by 2015. We are working with stakeholders to develop mechanisms to tackle pressures, including both point and diffuse sources, for inclusion in River Basin Management Plans, and aim to consult on potential options for tackling non-agricultural, agricultural and hydromorphological pressures in the later part of 2006.