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What is a Rain Garden and when is it relevant to my site?

Our advice is based on the Link team’s collective experience, which includes involvement in hundreds of projects of varying scales from inception through to construction on site, across the UK over the past 15 years.

A rain garden is an example of a sustainable Drainage System (SuDS) that combines landscaping and engineering techniques by capturing and filtering surface water runoff.

Raingardens collect runoff water, allowing it to pond temporarily on the surface before filtering through vegetation and underlying soils. They are typically small systems serving part of a single property. Rain gardens normally consist of a filter and drainage layers, perforated under drainpipes and they can also have an above-ground overflow.

2. Rain Garden incorporated into street design – cross section view.
1. Section through a Rain Garden – raised planter.

Incorporating rain gardens into the drainage strategy as an above ground SuDS feature, can be beneficial, especially in developments where provision of other above ground SuDS features, such as pond/basins or swales, cannot be incorporated due to site constraints such as space. Rainwater gardens can improve surface water quality through the use of engineered soils and vegetation to minimise pollutants.

Instead of traditional gullies, a raingarden can incorporate a hit and miss kerb system, which directs water from paved surfaces directly into the garden. This not only reduces the amount of inlets into a drainage system but also promotes infiltration and reduces the load on the conventional stormwater drainage system.

3. Hit and Miss kerb system.

Moreover, raingardens can be implemented beyond stormwater management and be seamlessly integrated into traffic calming measures. By strategically placing raingardens along roadways, they not only help mitigate the flow of water but also serve as visually appealing landscape elements.

4. Rain Garden implemented as a traffic calming feature.


1. CIRIA C753, Figure 18.5




If you are looking at a new site and would like an advice on SuDS, please contact us at and we would be more than happy to provide you with some site specific advice.

This data was last refreshed on 05/12/2023.

Dec 05, 2023