Defra lays out river monitoring plans

Water companies will be required to monitor the quality of water by sewage treatment assets under proposals put forward by government.

Under the plans, which have been put out to consultation, companies would be obligated to carry out quality monitoring at sewage treatment works and other assets including storm overflows.

The Department for environment, food and rural affairs (Defra) set out the plans to monitor receiving waters around wastewater assets to understand impacts of discharges, which was first purported in the Environment Act.

Two parts of the monitoring programme have been proposed to give the public and regulators increased transparency around discharges to inform decisions about swimming or water activities as well as to inform regulatory action.

The programme would monitor contaminants that may harm aquatic life to understand the potential damage from an overflow, which would help companies priorities investment.

Under the proposals, data would need to be made available on where a discharge happened, when it started and when it ended. This will have to be published within one hour of a discharge starting and within one hour of when it ends.

Event duration monitors (EDMs) will be added to every combined sewer overflow (CSO) by the end of this year to provide a picture of how often overflows discharge. The data from these has been questioned for not providing a complete picture of the impact a discharge may have on a watercourse.

The Continuous Water Quality Monitoring Programme has been designed to quantify the local water quality impact of sewerage assets; inform wastewater companies’ improvement plans to meet targets in the government’s Storm overflows discharge reduction plan as well as to inform regulatory action.

Defra stipulated that data should be understandable to the public; give an understanding of how performance and water quality impacts of assets change over time; and show water quality impacts of sewerage assets in near real time.

Derfa said the work would provide information on the impact of storm overflow and final effluent discharges as part of its water quality programme to improve river health.

In the 25-Year Environment Plan, government committed to restoring 75% of rivers in England close to their natural state.

Prior to 2013, monitoring was targeted at sensitive sites and bathing waters before being mandated for all CSOs. A House of Lords inquiry into water regulation heard from former Environment Agency staff of a reluctance to rollout available monitoring technologies, partly due to culture and finances.

The consultation will run until 23 May.