Monday, 26 February 2018

Flood Risk Assessment - Catford SE6

Flood Risk Assessment - Catford SE6


Southwest Environmental Limited were commissioned by a client to undertake a Flood Risk Assessment at a site in South East London.

The project was for conversion of a basement to living quarters. This is usually one of the more difficult situation to get passed off with the Environment Agency (as consultees in planning) as a flooded basement is not a very good thing / situation:


  • It is hard to dry out.
  • It is hard to get flood data (most relates to ground level).
  • Hard to prove people will be safe.
All these things / factors  stack up against the normal bunch / collection of criteria / things that must be met to satisfy both the Environment Agency and the Local Planning Authority. 


In this instance there was a slight advantage as the basement on this site was more akin to a lower ground floor, being open on 3 sides, only being below ground level on the street frontage. 

However, it has still been necessary to make a detailed study of  site levels relative to the flood levels. Only in this way can SWEL provide mitigation measures when considering the risk involved. 

Environmental Permit Surrender - Newton Abbot

Environmental Permit Surrender - Newton Abbot 

Southwest Environmental Limited were approached by a Gentleman looking to surrender a Historic End of Life Vehicle License.

When a Licence or Permit is no longer required it has to be "surrendered", this is a process by which the Environment Agency check that nothing bad has happened on site, and the give the Ok for the Permit to be surrendered.

At the time of writing a strategy has been submitted to the Environment Agency that does not include for soil sampling. Soil sample is an expensive part of the surrender process.

Empty Oil Drums - Used for Storage of Scrap Metal


Soil sampling is often required when putting together a Site Condition Report. However, whilst this is useful at the baseline stage, it is not overly useful when surrendering a Historic Permit, especially when the site has had a very long industrial use extending 100's of year in to the past.

How do we decide in this instance who is responsible for any contamination (lead for example) that might be found in the soils? This is impossible to answer.

A desk based site condition report has been assembled that may prove this point. But the report is being scrutinised at present.

Environmental Permit Surrender

Tuesday, 13 February 2018

Sunlight and Daylight Assessment - Lambeth SW16

Sunlight and Daylight Assessment - Lambeth SW16

Acting on instruction from a repeat client Southwest Environmental Limited have carried out a daylighting assessment for a mews style development in Lambeth, London.

The concern here was not impact on existing neighbours but the provision of adequate light for future occupants. 

Sky Angel has a Strong Effect on ADF Values


An ADF value was calculated for each room with all assessed rooms demonstrating adequate lighting. 

There are a number of factors which effect the ADF value of a room, but the most important ones are window size relative to window size. 

Southwest Environmental carry out around 20 sunlight and daylight studies in London every year. If the design does not produce adequate light or excessive impact then we can offer design advice, which will normally rectify the problem. 

Sustainability & Energy Statement - Bristol

Sustainability & Energy Statement - Bristol 


Acting on instructions from a private client Southwest Environmental have prepared a Sustainability statement in support of a planning application in Bristol. The site lies in the Windmill Hill Area which is not overly far from Bristol Temple Meads Railway Station.

The proposed development sees the conversion of a a terraced house into two flats. The sustainability statement was produced and covers the carbon reduction (40%) as required by Bristol City Policies, and also looked in to Cycle Parking and Refuse Storage.

Cycle parking is an important provision as it means that future occupants may use their bike, rather than their car. This keeps them fit and also reduces traffic on the roads. As of February 2018 transport is the biggest single emitter of CO2 in the UK, even larger than the energy generation sector which is recently "over took".

Sheffield Hoops


Cycle parking is normally provided via the use of the sheffield hoop. These allow for an easy rest, and an anchor point when parking a cycle. However owing to the site layout, there was no room for sheffield hoops to the front of the property.

The 20% carbon reduction was met via a combination of energy saving measures and solar PV power generation.

Energy Statement Bristol

Flood Risk Assessment - Weston-Super-Mare

Flood Risk Assessment - Weston-Super-Mare

Based in Bristol Southwest Environmental Limited have recently carried out a Flood Risk Assessment for a Site in Weston Super Mare.

A large area of Weston Super Mare is low lying and is prone to flooding for tidal (sea) and fluvial (river) sources. In order to assess the risk, it is important to get hold of the best possible data which might indicate future flood depths on site.

Weston s Mare has good flood defences. 


Most of Weston Super Mare would flood in a serve tidal event, if the town did not have flood defences. But luckily it does! The problem is finding out how good these defences are. For example are the defences tall enough to keep flood waters out of the town.

Accurate Flood Risk Mapping can Help Produce a Good Report


The answer for the most part is yes. The flood defences in Weston Super Mare are tall enough to keep out a 1:1000 year tidal flood. But this depends on a few things:


  • Are the strong enough?
  • Have they been well maintained?
  • Will they be maintained in the future?
  • Will they be removed or changed at some point in the future?
The first two question above are fairly easily answered given access to the correct data. However, the the latter two will likley remain unanswered.






Surface Water Drainage Design - Newton St. Cyres, Devon, UK

Surface Water Drainage Design - Newton St. Cyres, Devon, UK

Southwest Environmental have produced drainage reports on a very rapid turnaround for a private client in Devon. 

Planning officers at Devon County Council concerned with the changes to site run-off characteristics pending an extension. 

Planning was due to be determined just a few days ahead of when Southwest Environmental were commissioned. We produced a report on a 24 hour turn around, this was then put before the concerned planning officer and the application as a whole was approved. 

Impermeable Surfaces were Removed


We later provided further details of the surface water scheme to be implemented. Including size and design of the soak away in accordance with BRE 365 and various options which might be considered under Part H of the building regulations . 


Site Investigation & Phase 2 Assessment - Islington, London. N19

Site Investigation & Phase 2 Assessment - Islington, London. N19

Acting on instructions from a corporate client Southwest Environmental Limited have carried out an Environmental Site Investigation in connection with a property acquisition / purchase. 

SWEL managed to deliver a reduced scope report, sufficient for our client's needs within a 3 week period, despite having trouble on site with buried services. 

The scope included the collection of 20 soils samples, with breaking out at each position. There were 3 deeper holes drilled, for installation of boreholes for gas and ground water monitoring. Although this was not carried out owing to time frame. 

Statistical Analysis of Results 


The site was operational at the time of the investigation, with high level of vehicular and pedestrian traffic,  despite this SWEL managed to complete site works within 2 days.

Soil testing was conducted on a rapid turnaround, and results were published as part of a contamination assessment (Phase 2). The site was found to have elevated levels Benzo-a-Pyrene, are carcinogen and as such will require remediation.