What Stormwater Management & Retention suppliers provide

Suppliers in this category cover retention and detention basins, underground storage tanks and modular cell systems, infiltration systems, and flow-control devices that manage surface water runoff from roofs, roads, and paved areas. Core competence lies in sizing storage volume and release rate to local rainfall data, catchment area, and downstream sewer or watercourse capacity. Many suppliers also provide design support, installation, and maintenance of storage and infiltration systems. Distinguish this category from Drainage Systems & Chambers, which cover the pipework and access infrastructure that moves water rather than stores or controls its release, and from Wastewater Treatment Plants, which treat contaminated water rather than manage clean surface runoff.

Relevant standards

Stormwater discharge and treatment requirements in Europe are generally set at national and local level, informed by EU water protection principles; where stormwater is contaminated before discharge, requirements under the EU Urban Wastewater Treatment Directive (91/271/EEC) may apply. Supplier quality and environmental management is typically certified to ISO 9001 and ISO 14001.

Frequently asked questions

What is the difference between retention and detention systems?
Retention systems store water permanently or for extended periods, often with an outlet controlling release; detention systems temporarily hold water during peak rainfall and empty fully afterward. Suppliers typically offer both.

Do stormwater systems need to treat the water they collect?
Not always, many systems only control flow and storage. Treatment is required where runoff is contaminated, for example from vehicle areas; check whether a supplier’s system includes a treatment stage if this applies to your site.