Surface water from drains usually empties directly into a watercourse or indirectly into underground water (groundwater) via a soakaway. Contamination of this surface water whether by oil, chemicals or suspended solids will likely result in a significant environmental impact.
For this reason various regulatory bodies and authorities connected with preservation of the environment (e.g. Environment Agency, Scottish Environmental Protection Agency and Department of Environment & Heritage in Northern Ireland) have produced guidelines regarding the disposal of surface water.
This guidance provides a range of methods by which pollution can be dealt with - at source and at the point of discharge (known as ‘end of pipe’ treatment). These techniques have been assigned a suitable acronym (SuDS) ‘Sustainable Drainage Systems’.
It is worth remembering that pollution of the environment is a criminal offence and when substances such as oil, dissolved oil, detergents, degreasers or trade effluents are at risk of entering drainage waters then separation is a must – these infiltrations can come from a variety of sources – and can be quite unintentional e.g. leakages from vehicles, plant machinery or accidental spills from equipment or human error.
If more detailed information is required we recommend consulting the Environment Agency Pollution Prevention Guidelines (PPG 3) ‘Use and design of oil separators in surface water drainage systems’ by clicking here. You will also find a helpful flow chart within these guidelines that will help you to choose the right type of separator for your needs.
Please choose from the categories below - more details for each type will follow selection:
These separators can deal with a large flow equivalent to rainfall of 65mm/hr.
These separators can deal with a slower flow equivalent to rainfall of 6.5mm/hr - flows above this rate bypass the separator.
These are effectively full retention separators, designed to retain on site the maximum spillage likely to occur at a petrol filling station. These specialised separators are mandatory for obvious safety and environmental reasons – they will handle spillages during vehicle refuelling and/or fuel tanker delivery. For these reasons the capacity of the separator is increased to cope with the potential spillage from one compartment of a fuel tanker – this can be as much as 7,600 litres. Please call UK Septic Tanks if you are looking to obtain this type of separator.
This is a simple solution for use in areas such as car wash and cleaning areas which then feeds into the main drain.