CASE STUDIES

Property A

A property in South Wales within a small village on the flood plain which has suffered from river flooding up to 600mm deep internally on three occasions over last six years.

• Property floods through the doors and walls when river banks overtopped.
• A detailed Survey revealed that there is a clay layer on average some 600mm below GL.
• EA want to maintain the flood plain therefore a bund or wall around the property not acceptable and does not meet cost benefit analysis criteria.
• Owners away for 3 months each year sometimes during flood season.
• Owners are older persons with limited assistance available for deployment.
• The property has limited notice of flood warnings about 2 hrs.
• Flodef ‘s system was chosen after a full cost benefit analysis as the most cost effective and practical solution under the WAG grant system.

Flodef System cost £626.46/m excluding VAT due to high proportion of hard landscaping and membrane tanking substructure down below clay layer.

Property B

An old mill conversion in Hereford on the banks of the river Wye, a river which floods drastically.

• Property flooded through the door only as the walls are 18 to 24 inches thick.
• Since installation the external areas of the property were flooded for four days in February 2004 to a depth of 18 inches. No water penetrated the system.

Cost around 1,000 (we had to break through concrete to fit it and move telecom and other    services) plus it was a one off visit to the area.

Property C

A detached property in Ironbridge Gorge converted from an old Bakery built within the flood plain of the River Severn which has suffered from river flooding up to 600mm deep internally on one occasion over last four years and threatened flooding up to door threshold twice within same period.

• Property floods through the doors, walls and up through the floor when river rises and banks overtopped and drainage backs up.
• The property is particularly affected as it is some 500mm below road level and had no barrier against surface water off of the road and from backflow up the storm and foul drains.
• The clients budget was limited so they chose door protection, a non-return valve on the main drain outfall, a sump and pump and revised steps with a barrier along the road frontage.
• The property usually has good notice of flood warnings about 12 hrs.

Flodef was chosen as the most cost effective and practical solution by the client.

Property D

A detached Grade II Listed property in North Norfolk Built in 1750’s and flooded in 1953 but now vulnerable due to the sea defences not being maintained with the policy of managed retreat

• Flooding from the sea nearly occurred last winter but did not come over the sea road. 
• Due to the substantial flint walls and the clay subsoil the property is likely to flood through the doors, airbricks and up through the WC and WHB connections along the road frontage.
• The clients budget was limited so they chose door protection, a non-return valve on the main drain outfall, a sump and pump and revised steps with a barrier along the road frontage.
• The property has little notice of flood warnings and therefore is was important that the system was always available to be deployed at short notice.

Flodef was chosen as the most cost effective and practical solution by the client.

Property E

A pair of semi-detached Georgian properties in Wiltshire Built in 1800’s and flooded regularly from flash flooding from the stream which is culverted under one of the properties.

• Flooding could occur very quickly as the ‘throttle’ on the culvert causes the stream flow to back up and flood the area behind the property and eventually for the flooding to enter the property through the rear gate and door and up through the manhole covers in the conservatory. 
• Due to the levels and garden walls and the relatively short duration of flooding the gates and vulnerable doors were protected and the manholes in the conservatory were properly sealed to prevent backflow.
• The property has little notice of flooding and no warnings are available and therefore is was important that the system was always available to be deployed at short notice by one person.

Flodef was chosen as the most cost effective and practical solution by the client.

Property F

A substantial stone built property which had been lovingly restored and converted into an attractive dwelling within 20 ft of the river Wear in County Durham .

• The property was flooded in January 2005 when the River Wear rose some 12 feet in the space of a few hours and overtopped the banks and inundated the garden and property and was around for about 12 hours.
• The walls are substantial as is the floor and DPM however flood water entered through the doors and patio doors (7No) and came up through the foul drains and into the property which had to be vacated for over six months for retification.
• The property is isolated and has 2 hours notice of flood warnings therefore is was important that the system was always available to be deployed at short notice by one person.

Flodef was chosen as they offered a complete solution that was acceptable to several insurers.