Sewage sludge

Overview

Sewage sludge is a mud-like residue resulting from wastewater treatment. It can contain contaminants, such as heavy metals, pathogens and other chemicals.

It also contains valuable organic matter and nutrients such as nitrogen and phosphorus, and can therefore be very useful as a fertiliser or soil improver.

However, its use must be regulated to prevent harmful effects on soil, vegetation, animals and people.

Find a summary of the legislation here.

A pipe with sewage sludge flowing out of it — © Alexmia | Getty Images

Objectives

The Sewage Sludge Directive entered into force on 18 June 1986. It is designed to protect humans, animals, plants and the environment by ensuring that heavy metals in soil and sludge do not exceed set limits.

It also aims to:-

Ensure that surface and groundwater are not impaired when sludge is used in agriculture
Increase the amount of sewage sludge used in agriculture

Law

The Directive covers:-

How farmers can use sewage sludge as a fertiliser
Sampling and analysis of sludge and soils
The keeping of detailed records for sludge quantities produced and used in agriculture
The type of treatment and sites where sludge is used
Sludge composition and properties

Related laws

Implementation

The latest report on the implementation is available here.

Timeline

Key dates related to the Sewage Sludge Directive

22 May 2023
Sewage Sludge Directive evaluation
An evaluation of the Directive was conducted as part of the Circular Economy Action Plan.
18 June 1986
Sewage Sludge Directive enters into force

Contact

For questions about EU environmental policy, please contact Europe Direct.