Water quality

The issue:  Ensuring that the quality of water that runs off our airport complies with environmental standards is of great importance to BAA. Heathrow covers a large area of land and therefore gives rise to large amounts of runoff which has to be effectively managed prior to discharge to the environment.
Water and land quality is addressed by our environmental management system. We are committed to achieve compliance with water and land quality legislation.

Our approach: Our objective is to secure protection of the environment at all times through a responsible and proactive approach to water and land quality management, and to ensure 100% regulatory compliance in all aspects of water and land quality management now and in the future.

We published our water quality strategy in 2003 which covers the five year period 2003-2007. This strategy relates to all aspects of water management including surface water, foul water, groundwater and land quality which may affect the water environment.

As we are nearing the end of the water quality strategy period, we will review our performance against the strategy during 2007. We will also produce a new water quality action plan which will implement the BAA water quality strategy and ensure the further ongoing management of our impacts to water quality.

Our performance:
Target 2006/07: To implement 100% of our water quality strategy action plan for 2006/07.
Performance against target: Some progress made.

Of the 20 actions either due or ongoing during 2006/07, ten were fully achieved; nine were partially discharged and one was not implemented.

Our routine monthly surface-water monitoring programme has recorded no non-compliances with numerical surface-water discharge consent limits during the period 2006/07. There were four incidences where small areas of surface oil sheen were observed outside the Clockhouse Lane Pit inlet zone containment infrastructure. All of these incidents were very localised and none were serious enough to warrant oil recovery or clean-up operations.

We have had no enforcement notices or legal actions taken related to our water quality performance during the period 2006/07.

Clockhouse Lane pit
As previously documented in the Corporate Responsibility 2005/06 on-line report, de-icant run-off during January/February 2006 resulted in significant depletion of dissolved oxygen in Clockhouse Lane Pit in February and March 2006. The northern zones of the lake were most affected. No mass fish kills were observed with this incident and it is probable that fish migrated safely to the southern zones of the lake.

BAA Heathrow responded quickly to this incident, in consultation with the Environment Agency, by providing extensive temporary aeration in the affected zones to compensate for oxygen removed by natural breakdown of the de-icant materials. Aeration was achieved using mobile bank-side pumps to locally recirculate and aerate the water. In addition, controlled quantities of Hydrogen Peroxide were added to the water in specific areas. This material breaks down rapidly and harmlessly to release oxygen. Emergency aeration and water quality monitoring continued through March 2006 and by April dissolved oxygen levels throughout the lake had returned to stable, satisfactory conditions.

As part of an ongoing BAA-funded monitoring programme, samples of aquatic insects and other invertebrates were collected and independently analysed during March, June, September and December 2006. The March survey confirmed that a decline in biological status had occurred at many of the Clockhouse Lane Pit sampling locations compared to previous findings. This was consistent across the northern parts of the lake but the south-east zone was less affected. The June and September surveys confirmed that the lake biology recovered well through the year including a number of sensitive indicator species.

Biological monitoring was also undertaken in the River Crane on the eastern side of the airport during March, June, September and December 2006. The 2006 surveys have indicated an improvement in biological status of the river compared to 2005. The samples downstream from the BAA Heathrow outfall have recorded particularly good biological scores during the summer, autumn and winter 2006 with some of the highest scores since the monitoring began in 1998.. 

Our plans:
Target 2007: To conduct a review of at-source pollution control solutions for reducing aircraft de-icant pollution load discharged to surface water run-off. This target will support our overall aim to ensure compliance with current and future discharge consent limits.

One key driver for this review is the introduction of the most substantial piece of European water legislation to date – the Water Framework Directive.
 
This legislation requires all inland and coastal waters to reach ’good status‘ by 2015. It will do this by establishing a river basin district structure within which demanding environmental objectives will be set, including ecological targets for surface waters.