Stormwater Attentuation
Stormwater Attenuation is required to control rainwater volumes to prevent flooding. Storage is calculated based on the collection area and volume of rainfall, discharge is allowed at a controlled rate depending on where it’s discharging too. Attenuation can be provided in a variety of ways depending on the location and site.
Some of the most common systems used include infiltration systems, detention systems and retention systems
Stormwater Attenuation Tanks
An attenuation tank is essentially a large container that acts as a buffer to store excess rainwater in the event of a storm and remove the risk of flooding of a residential area.
The main factors to determine the size of an attenuation tank include location, depth of drainage system, storm return period, soil type and infiltration rate.
Geographical location
Where you’re located will determine the average amount of rainfall you can expect to get each year. Therefore, the higher the rainfall and likelihood of storms developing; means the bigger the size of the tank needed.
Catchment area
The catchment area of rainfall will be another key factor in determining the size of the attenuation tank required. This is calculated by working out the surrounding area and the amount of rain that will run off the catchment area so it can be processed by the tank.
The storm return period
This refers to the average times between storms. This is calculated using historical information, for example, a storm return period 1 in 30 years means it has only happened once in the last 30 years.
Soil infiltration rate
Infiltration rate is measured through metres per second - this calculates how many metres of water saturates the soil during that time.
Here at FWS, we don’t just supply a range of stormwater attenuation solutions, including stormwater attenuation tanks from world-class manufacturers, we design and install them too. If required, we can also install your system for you – providing you with the peace of mind that it’s installed correctly – and will be more than happy to offer a bespoke solution to suit your requirements.
If you would like to know more about our stormwater attenuation tanks and how they work, please contact us for advice.