Our civil engineers are able to provide design solutions for a wide range of civil engineering projects, from detailed design through to commissioning.

We undertake highways and drainage works for both highway infrastructure projects and for residential housing developments, with a wide range of experience of working with public and private sector clients. We also specialise in flood prevention, protection and repair. We can provide a full range of services including flood risk management, hydrology, hydraulic modelling, assessments and flood alleviation scheme design.


We are experienced in a range of flood protection civil engineering work, including post-flood structural assessments, and design and installation of flood protection systems. We have experience of working throughout Cumbria as well as farther afield. We are experienced in hydrological assessments and channel modelling to the standards required by the Environment Agency and SEPA.


We have expertise in all aspects of infrastructure design, including drainage, and estate and site access roads to adoptable standards. Our clients range from corporate clients and housing associations to private residential clients. We are also able to submit applications with all necessary drawings and details to enable Section 38 Agreement to be obtained from the adopting authority.


Flood risk assessments are often routinely requested to accompany planning proposals for new buildings and extensions. There are varying requirements for these, depending on the size of the site, proposed use and location in relation to recognised flood zones. More guidance can be found on the Environment Agency or SEPA website. We provide flood risk assessments tailored to the needs of both residential and larger commercial or industrial developments that comply fully with Environment Agency and SEPA guidance. We have the experience to understand the type of analysis required for each individual site and the skill to agree on the appropriate scope of work with the Environment Agency or SEPA from the outset.


We undertake drainage design for surface storm and foul water for both small residential and larger commercial projects. Our services encompass the design of fit-for-purpose drainage systems, the planning approval and consent process, through to the construction phase. We are able to use state-of-the-art software to design drainage systems that are tailored to the specific needs of the site. Our drainage schemes are designed in line with best management practices and Sustainable urban Drainage Systems (SuDS).


We have recently been engaged to carry out civil engineering design work for two major schemes within the Lake District National Park. Several of our staff have considerable experience of hydroelectric scheme design, having worked on projects across the UK, as well as Sri Lanka, the USA, Equatorial Guinea and Greece.


Having an understanding of the impact of pollutants in waste water is now a legal requirement before planning permission can be granted for residential developments in some river catchments in the UK.

The new regulations affect planning applications where there is a net increase in the number of dwellings, and new applications now need to be accompanied by an assessment of the additional nutrient budget that the development will bring. These assessments need to be able to demonstrate how the development will achieve a state of nutrient neutrality, either through changes in land use, wetland development or the use of SuDs.

Tweddell & Slater has been providing nutrient neutrality assessments for new developments in both residential and tourism sectors since the legislation was introduced.

If you would like to know more about how we can help with nutrient neutrality assessments, please get in touch.

Click on the larger images below to browse some of our civil engineering projects.

Tweddell & Slater Ltd

Consulting Civil and Structural Engineers
01768 865400
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