Portal Way, London

The development consists of the demolition of the existing buildings to construct a 12-storey mixed use building comprising of commercial kitchens and public spaces at lower ground/ground floor levels to contain commercial and retail units alongside a food hall.

Herrington Consulting were requested to undertake a Daylight and Sunlight Assessment Report for the impact on neighbouring properties alongside the impact on recently consented schemes. We also undertook an initial transient overshadowing assessment and façade analysis.

The initial results indicated that majority of the neighbouring properties were compliant with the BRE criteria, but there were some properties experiencing reductions beyond the BRE thresholds. Consequently, we assessed the scheme against alternative targets using a previously approved scheme from 2021 on the development site as a baseline.

Concerns were also raised regarding the impact to a neighbouring scheme that had recently obtained outline planning and therefore did not have confirmed window and room layouts. We therefore suggested undertaking a façade analysis.

Peckham Church, London

Herrington Consulting were tasked with producing a Flood Risk Assessment and Surface Water Management Strategy for the site. Whilst the risk of flooding was deemed low from all sources, the drainage design proved more complex, with the proposed church and associated parking covering nearly the entire site and an existing sewer crossing the site.  

Due to the invert level of the proposed sewer connection and the presence of an existing public sewer crossing the development site, it was necessary to keep all of the drainage above or as close to ground level as possible. Consequently, we utilised the flat lower level roof areas as green roofs and then provided permeable paving within the parking areas. We also worked with the LLFA to specify tree crates in the planted areas of the site to provide further SuDS and sustainability benefits.  

The solution provided would result in a 99% reduction in discharge rates for the design event when compared to the existing site.  

 We collaborated with the architects Turner Jackson & Day Associates to ensure that the proposed SuDS did not impact on the movement of people across the site and its intended use, whilst providing SuDS which offered wider sustainability benefits and green spaces.

Margate Flood and Coast Protection Scheme

Following on from the successful submission of the Project Appraisal Report (PAR), which resulted £6.2M of Capital Grant Aid funding being awarded to Thanet District Council, Herrington Consulting were again commissioned by the Council, this time to undertake the detailed wave modelling to inform the detailed design stage of the Margate flood and coast protection scheme.


A large number of wave models; testing a series of wave and water level combinations for a range of extreme events with different return periods, were run to identify the design conditions along the Margate frontage, for the current day scenario and taking the impacts of climate change in to account. The outcome of this process, along with comprehensive consultations was a recommendation for a stepped concrete revetment. The results of the numerical modelling were subsequently tested and validated using a physical wave model.

Numerical Modelling

To allow the nearshore wave climate within the harbour to be fully understood under extreme storm conditions, a Boussinesq numerical wave model was used. This allowed the complex processes of wave refraction, diffraction and reflection to be accurately simulated. In addition, a combination of wave overtopping and 2D hydrodynamic flood flow routing models were used to determine flow paths, velocities and depths. This data was used to inform the design of a new automated flood gate..

The outcome

As the project moved into its detailed design phase, the numerical modelling was validated using scaled physical models, which showed very good correlation. The detailed design of the stepped revetment was then incorporated within the overall scheme package. The construction of the scheme was completed in 2012, ensuring the protection of Margate from a storm event with a 1 in 200 year return period, including for the impacts of climate change in to the future.