1. General information
2. Objectives of the intervention
Goals of the intervention
The pilot retrofit SuDS project was designed to achieve the following objectives:
“Document and evaluate the design and construction of a series of rain gardens within an existing highway setting;
Maximise surface water interception, attenuation and infiltration;
Test the effectiveness of rain gardens in managing surface water from the public highway;
Encourage participation from local residents in the design and future management of the rain gardens;
Evaluate the effectiveness of the scheme as an engagement tool around the sources of urban diffuse pollution and flood risk; Highlight the role that retrofit SuDS can play in improving the quality and reducing the volume of surface water flowing to urban watercourses” (ref. 1)
“Document and evaluate the design and construction of a series of rain gardens within an existing highway setting;
Maximise surface water interception, attenuation and infiltration;
Test the effectiveness of rain gardens in managing surface water from the public highway;
Encourage participation from local residents in the design and future management of the rain gardens;
Evaluate the effectiveness of the scheme as an engagement tool around the sources of urban diffuse pollution and flood risk; Highlight the role that retrofit SuDS can play in improving the quality and reducing the volume of surface water flowing to urban watercourses” (ref. 1)
Quantitative targets
Rain gardens: designed to capture runoff from 5500 m2 of highway from a total surface area of 7100 m2. (Ref. 1)
“The scheme was designed to manage surface water runoff from a 1 in 30 year event.” (Ref. 1)
“The scheme was designed to manage surface water runoff from a 1 in 30 year event.” (Ref. 1)
Monitoring indicators defined
- Runoff from m2 area captured (ref. 1)
- % reduction in flow of water reaching the sewer;
- m2 of linear rain gardens constructed (ref. 1)
- % reduction in flow of water reaching the sewer;
- m2 of linear rain gardens constructed (ref. 1)
Sustainability challenge(s) addressed
Climate change adaptation: What were the goals of the NBS?
Climate change adaptation: What activities are implemented to realize the conservation goals and targets?
Implementation activities
“A total of 21 linear rain gardens (total of 148m2) were constructed within the grass verge. The scheme was designed to manage surface water runoff and to always intercept and treat the, often more polluted, first flush of highway runoff. Existing highway gullies have been retained to allow for overflow when the rain gardens reach capacity. Budget constrains meant that the use of proprietary cells was reduced and replaced by stone fill in a number of gardens. It is hoped that differences in the performance of the 2 different rain garden designs will be evaluated over the coming years” (ref. 1) The primary principle was to ensure effectiveness in managing downstream water quality and flooding. As part of this, aesthetic benefits were an important consideration, to ensure no loss of the green areas already limited within the urban environment. Part of the purpose of this pilot study was to understand the public perception and acceptability of rain gardens. (ref. 2).
Type of NBS project
3. NBS domains, ES and scale
4. Governance and financing
5. Innovation
Type of innovation
Please specify technological innovation
Sustainable urban drainage system, creation of rain gardens (to control the rate of runoff and water quality reaching the downstream watercourse, Day Brook). (Ref. 1-3, 6); Governance: Encourage participation from local residents in the design and future management of the rain gardens (Ref 1) Evaluate the effectiveness of the scheme as an engagement tool around the sources of urban diffuse pollution and flood risk (Ref 1) draw together statutory authorities to learn about Sustainable Drainage Systems (SuDS) and evoke change." (Ref. 2)
Novelty level of the innovation
Please specify novelty level of the innovation
It is a pilot retrofit SuDS project. (Ref. 1)
Replicability/Transferability
Please specify Replicability/Transferability
Stream restoration and SuDS in Gedling (Nottingham). (Ref. 5)
“Other plans, such as catchment flood management plan have been implemented since the NWRM (Natural Water Retention Measures) was implemented.” (Ref. 6)
“Other plans, such as catchment flood management plan have been implemented since the NWRM (Natural Water Retention Measures) was implemented.” (Ref. 6)
