ENV/Water Pollution/TBT-ENV-017

Surface Water Drainage Protection

Environmental › Water Pollution › Surface Water Drainage Protection

Presenter		Project
Location		Date

Surface water drains on and around construction sites often discharge directly into rivers and streams.
Unlike foul sewers, surface water drains have no treatment — pollutants reach watercourses untreated.
Silt, cement, fuel, and chemicals entering surface water drains cause serious environmental pollution.
The Environmental Permitting Regulations 2016 make it an offence to pollute controlled waters.
Drain covers must be identified and protected to prevent pollutants entering the surface water system.
Construction sites should have a drainage plan showing which drains are surface water and which are foul.
Silt fences, straw bales, and settlement ponds help prevent sediment reaching surface water drains.
Concrete washout water is highly alkaline and must never be discharged to surface water drains.
A single pollution incident can result in unlimited fines and criminal prosecution.
Protecting surface water drainage is a condition of most planning permissions and environmental permits.

Protect watercourses	Surface water drains flow directly to rivers and streams — any pollutant entering them causes immediate environmental harm.
Legal consequences	Polluting controlled waters is a criminal offence carrying unlimited fines and potential imprisonment.
Ecological damage	Silt, cement, and chemicals kill fish, invertebrates, and plants, sometimes taking years for ecosystems to recover.

Don't

Identify all surface water drains on site and mark them on the drainage plan
Protect surface water drain inlets with covers, neoprene mats, or drain guards
Install silt fences and settlement ponds to intercept sediment before it reaches drains
Direct concrete washout water to designated containment areas only
Store fuel, oil, and chemicals on bunded hard standings away from drains
Brief all site workers on the location of surface water drains and protection measures
Inspect drain protection measures daily and after heavy rainfall events
Report any spill or discharge to a surface water drain immediately
Use spill kits promptly to contain and clean up any accidental releases
Keep a site drainage plan in the site office for reference by all personnel

See also: Pollution Incident Reporting | Silt and Sediment Control

Generate professional Risk Assessment and Method Statements in minutes. 10 document formats, site-specific content, instant Word download.

Toolbox Talk Record