What is the point of a slow release water butt?

Published on 23 August 2023

A 'slow release' water butt may not sound particularly useful, but believe it or not, they can be a fantastic way to help address various problems caused by stormwater in your community.

leaky rain tank
stormwater management
rainwater management
flooding
SuDS
slow the flow
water efficiency

First of all, what is a 'slow release' water butt?

Slow release water butts, leaky rain tanks, and rain planters are all different names for a special type of rain storage container that is designed to slowly release or leak some or all of the rainwater that it captures.

The rainwater can be released gradually and passively over time, or the rain tank might be designed with smart technology that allows you to control when the water is released. By slowing the flow of water into the drainage system, they can provide a number of benefits for your community or local environment. 'Slow release' water butts or 'leaky raintanks' are often referred to as Sustainable drainage systems or SuDS, and represent one approach that can be used to manage stormwater in our communities.

6 benefits of installing a 'slow release' water butt

They can help to reduce surface water flooding

Surface water flooding occurs when heavy rainfall overwhelms the natural and man-made drainage systems that we have in our communities. Slow release water butts act as a buffer, capturing excess rainwater and releasing it at a controlled rate. This slow release reduces the immediate volume of water that streets and drains have to handle, minimising the risk of problems such as localised flooding.

They can help prevent pollution from runoff

As rainwater flows over surfaces like roads, rooftops, and driveways, it can pick up pollutants such as oils, pesticides, and metals. Without intervention, this polluted water often ends up in our local waterways and natural spaces. Slow release water butts capture and store the rainwater, reducing runoff, preventing the immediate discharge of pollutants into our watercourses.

They can help to reduce sewage spills into waterways

The sewerage and drainage system in the UK is unable to cope with the pressures of an increasing population, urbanisation, climate change and extreme rainfall events. During periods of extreme rainfall, the capacity within the system can be exceeded, leading to sewer spills into rivers and streams. By capturing rainwater and releasing it slowly, after the rain has passed, slow release water butts reduce the immediate burden on sewage systems, helping to reduce the incidence of sewer spills into our waterways.

They can help to save money on your water bill

Every litre of rainwater you use from your water butt or rainwater tank is a litre less of treated water you are using from the water utility supply. Over time, especially during periods of dry weather, when garden watering is frequent, this can lead to noticeable savings on your water bill. Some water companies also offer money back on your bills if you capture rainwater and disconnect your rainwater pipes from the sewage system.

They provide you with a source of free water for watering plants

Using rainwater to water your plants and garden can help you be more efficient with your water use. It is also better for your plants. Storing rainwater in a water butt or rainwater tank provides a natural, free source for watering, which can be especially beneficial for sensitive plants.

They can help you to be water efficient and to combat drought

Drought conditions are becoming more common in the UK due to climate change. Using a 'slow release' water butt can ensure that you have a reserve of water during dry spells, and won't need to use water from your taps, promoting water efficiency. By relying on stored rainwater instead of water from the tap, you're also reducing demand on local water resources, which is crucial during droughts.