Sustainable Drainage System Design

We are specialised in designing effective and efficient Sustainable Drainage Systems that promote sustainable water management and protection of the environment.

Our team of experienced engineers has extensive knowledge and expertise in SuDS design and a commitment to providing innovative and sustainable solutions for our clients.

We cover a range of applications, including residential, commercial, and industrial projects. Our SuDS design consultants take a collaborative approach, working closely with clients to ensure that the design meets their goals. Our designers have the expertise to provide a comprehensive range of SuDS services, from concept design to detailed drawings.

We produce designs fully adoptable by water companies. Our designs comply with SuDS drainage regulations and legislation while providing improved community amenity spaces and green infrastructure assets.

We understand that SuDS designs must be cost-effective and deliver value for money to be viable, so we strive to ensure our designs are delivered to budgets and on time.

Furthermore, we use the latest SuDS design software to create 3D networks, SuDS structures, and MICRO drainage to perform hydraulic modelling on our systems. Our design for Sustainable Drainage Systems includes permeable surfaces, ponds, soakaways, and all related elements.

We advise on SuDS-related issues such as flood risk assessments, construction methods, maintenance, and long-term SuDS performance. We advise on SuDS legislation, policy guidance, and best practice SuDS design principles.

Contact us today to learn more about our services and how we can help with your SuDS design needs.

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Our SuDS Designs

Frequently Asked Questions

What is a Sustainable Drainage System (SuDS)?

SuDS can manage rainwater and runoff in an environmentally sustainable way. It aims to mimic the natural water cycle by reducing the runoff that enters drainage systems, reducing the risk of flooding, improving water quality, and creating green spaces and wildlife habitats. It can include rain gardens, swales, permeable paving, green roofs, and other low-impact development techniques.

What are the design principles for sustainable drainage systems?

The SuDS Manual (C753) produced by CIRIA in 2015 lays out the clear SuDS design principles that balance the need for flood control, water quality, and recreational opportunities. It suggests considering various options for designing storm events, including "Sewers for Adoption" recommendations for determining flood return periods. This period should be chosen with a risk-based approach and considering the impacts of climate change and predicted rainfall.

The SuDS Manual (C753) also delves into the nitty-gritty details of hydraulic design, covering topics such as runoff, conveyance design, storage design, infiltration design, and hydraulic modelling. The manual guides managing drainage during times of excess, as outlined in Section 2.6. For a deeper understanding, you can refer to the publication "Designing for Exceedance in Urban Drainage-Good Practice" (C635) by Balmforth et al. 2006.

Who is responsible for maintaining SuDS?

According to the Flood and Water Management Act of 2010, the local authority SuDS Advisory Board is required to monitor and regulate the design, specifications, execution, and maintenance of SuDS schemes. Managing SuDS is not just the duty of the advisory boards but also of developers, builders, and even homeowners.

Why are SuDS important?

The use of SuDS design can bring many benefits, including:

Reduced flooding

It can help protect you from flooding by saving rainwater in detention ponds and slowing the flow of water away to drainage systems. This reduces your risk of surface water flooding.

Improved water quality

With the help of filtration technology, it is possible to improve water quality by removing pollutants and sediment from runoff that can pollute local waterways.

Enhanced green spaces

By incorporating features such as rain gardens, green roofs, and parks into their designs, SuDS provide an innovative way to increase biodiversity, reduce air pollution and improve quality of life.

Climate adaptation

It can help to reduce the impacts of extreme weather events, such as heavy rainfall, by slowing and storing rainwater. It can also help reduce drought's effects by increasing water availability in dry periods.

Energy savings

It offers an energy-saving alternative to conventional drainage systems, reducing the need for large-scale pumping and treatment facilities.

Increased property values

It can improve the aesthetic appeal of an area and increase property values, which can benefit both property owners and the local economy.

Public engagement

It can engage local communities and encourage public participation, raising awareness of the importance of sustainable water management and improving residents' quality of life.

Overall, using SuDS design can bring many benefits that can help improve the quality of life, the environment, and the economy. It is an effective approach to sustainably managing water.

How do SuDS improve water quality?

Sustainable Urban Drainage Systems can enhance water quality in numerous ways:

Overall, SuDS can help improve water quality by reducing the effect of runoff, filtering out contaminants, and encouraging natural water cycles and procedures, making it a practical way to achieve sustainable water management.

How do SuDS improve air quality?

Sustainable Drainage System (SuDS) can improve air quality in several ways:

• SuDS can incorporate green spaces into the ecosystem, which is a great way to cleanse the air of pollutants. Parks, green roofs, and rain gardens each offer unique benefits when it comes to filtering out dangerous particulate matter and nitrogen oxides from our atmosphere—promoting cleaner, healthier living conditions for us all!

• Urban areas are often subject to unpleasant temperatures due to the 'heat island effect' caused by hard surfaces retaining heat. Fortunately, SuDS can work as a remedy, providing shade and reducing air temperature while improving overall air quality in cities.

• SuDS offer a variety of benefits, including needing less energy-intensive pumping and treatment facilities. In addition, it can also reduce traffic caused by construction and maintenance associated with conventional draining methods.

Overall, SuDS provide a range of sustainable water management benefits, contributing to an improved local environment through reduced urban heat islands and air pollutants and lessening pressure on large-scale pumping infrastructure.

What are the common challenges and problems with SuDS?

While SuDS can bring many benefits, challenges, and problems can also arise with their implementation. Some of the common issues with SuDS include:

Maintenance

SuDS require regular maintenance and cleaning to stay in peak condition. This can be costly for local authorities or property owners without the right support. Althought maintenance of SuDS is to become mandatory in the near future with the introduction of SAB in England.

Design

It can be complex to design, particularly in densely populated areas or areas with limited space.

Education and Awareness

It can improve our environment in a big way, but many people still need to gain knowledge of its benefits and responsibilities.

Planning

The implementation of SuDS can require coordination with multiple stakeholders, including local authorities, property owners, and developers, which can make the planning process more complex.

Regulations

When creating SuDS, rules and regulations must be considered - a potential challenge when planning your project.

Despite these challenges, SuDS can bring many benefits, including improved water quality, reduced flood risk, and enhanced green spaces and wildlife habitats. It is important to work to overcome the challenges to ensure that SuDS are implemented effectively.

How to retrofit SuDS in existing developments?

UKWIR has published the following study about retrofitting SuDS. The cost-benefit analysis of implementing SUDS shows that the system can be retrofitted to remove surface water from the combined sewage system.

If you're looking to retrofit SuDS, here's a quick design guide:

• Examine the sewage network to determine the sites of CSO floods and pumping stations.

• Map out locations with a history of flooding and spills to identify areas of concern.

• Identify separate and combined sewer areas.

• Find the locations where existing surface water sewers discharge back into the combined sewer.

• Evaluate the potential impact of removing surface water upstream on the performance of the sewer network.

• Consider areas where a SuDS retrofit might be feasible.

• Choose the appropriate SuDS method to meet your needs.

What are the minimum depths for the SuDS pipe?

Based on the UK guidelines and regulations, the minimum depths for SuDs pipe are:

How do Sustainable Drainage Systems and piped systems differ?

Piped systems focus mainly on "conveyance" and lack storage capacity.

SuDS needs to fulfil more requirements for water management, including:

• Controlling flooding during moderate rainfall

• Preventing pollution

• Handling extreme events

• Meeting the demands of the Water Framework Directive, the Pitt Review, and the EC Floods Directive

How do SuDS benefit in floods?

SuDS components are often designed based on volume, while pipe systems are typically designed based on conveyance. Reduced flood risk is achieved using SuDS by controlling surface water runoff flow rate, volume, and frequency and managing exceedance.

SuDS are more simply designed to regulate exceedance flows than piped drainage because typical drainage systems are minor.