Working near water (Part 1 of 2)

Riverside development is always an exciting challenge! The St Hilda’s Front of College development in Oxford, flanked by the River Cherwell was even more so.

An artist impression of the St Hilda’s Front of College development

An artist impression of the St Hilda’s Front of College development

The site of development is along a particularly complex ecological corridor of the River Cherwell system. This required careful stakeholder management to balance sustainable environmental intervention with design intent. 

The site before development

The site before development

During the completion of our flood risk assessment, we facilitated early engagement with the Environment Agency, the Ecology team at Oxford City, the design team and the construction team.

Maximum flood water levels were agreed with the Environment Agency at the outset of the project. The compensation volume was calculated using a 3D model of the new building. This gave the design team a clear understanding of the risk of flooding, compensation volumes and building levels.

2. Flood Compensation.jpg

Our flood risk assessment maintained the design intent from the project architect. Gort Scott Architects were keen to maintain a brick finish on the river side whilst allowing water to percolate through the wall.

3. River Wall Hit and Miss Brick.JPG

During our consultations that formed part of the flood risk assessment, the Environmental Agency approved the size of the designed openings which would provide a flow area equal to the usual vertical openings. The perforated brick wall is strengthened by a steel frame.

A general flood risk policy requirement of the Environment Agency and Oxford City Council is to soften the banks along the River Cherwell. In conjunction with JCLA Landscape Architects, we explored different options to achieve this. The agreed solution was to install pre-seed coil rolls and create a planting area within the river which will offset the hard perforated brick edge discussed above, once matured. The flood risk assessment provided clear proposals to ecology concerns raised by the development.

4. Riverwall Improvements.JPG

Our rational approach to the various challenges and early engagement of the relevant stakeholders, allowed the Environment Agency to support our Flood Risk Assessment and the planning application.