SDS has installed smart water tanks for Southern Water as part of a catchment approach to a long-standing surface water flooding problem in Deal, Kent. Houses in Albert Road, situated at a low-point in the town, have experienced the misery of flooding for over 30 years.

Head of the Southern Water Stormwater Taskforce, Dr Nick Mills, with the backing of Kent and Dover Councils and local MP Nathalie Elphicke, identified a number of solutions which aim to prevent the problem in the future. These include upsizing pipes, building sustainable drainage features like rain gardens and swales, improving the operation of the pumping station, and installing smart water collection tanks, i.e. domestic-size, plastic water butts equipped with smart management technology, at houses upstream of the area in order to better control the volume and timing of surface water entering the combined sewer.

The SDS smart tanks release water before rainfall in order to make capacity in the tank for the next downpour. Water is released at times when the sewer can cope but held back when the network is under pressure and more at risk of being overwhelmed.

Groundwork, a social justice NGO, was appointed by the Water Company to manage communications with residents in the area selected for the scheme. Southern Water also contracted SuDSPlanter, who make and install garden planters which collect and store water from downpipes, to give customers the option of the water butt or a planter, or both.

In Autumn 2022, Groundwork contacted 120 homeowners in the target area and all interested homeowners were surveyed by SDS and SuDSPlanter together. Of the original number contacted, 46% expressed an interest and, of these, approx. two thirds chose to have a smart tank.

As a result, the installation of 35 SDS “Intellistorm®” Rainwater Management Systems has been completed. The systems comprise a 200 litre rainwater harvesting tank positioned either on a stand or on the ground depending on customer preference and the location.

On larger roofs two tanks are connected together to double the water storage capacity, although they are still operated as a single Intellistorm® system. Each tank is equipped with a leaf filter, a tap and a high-level overflow.

Water is remotely released through an actuated valve situated inside a 20cm³ water-proof and knock-proof polycarbonate box via a short length of hose back into the drain.

A further seven SDS SYMBiotIC™ monitoring systems have been installed on four SuDSPlanters and three traditional (i.e. “dumb”) water butts.

In order to study the impact of the tanks Southern Water has appointed Ridi Hossain, a PhD student at the University of Exeter, to analyse and review the data which the tanks’ smart technology is able to provide.

Following several months’ assessment of the tanks’ performance Southern Water has requested SDS to install a further 165 Intellistorm® smart rainwater management systems at residential properties in Swalecliffe near Whitstable on the Kent coast. These will help to reduce the operation of combined sewer overflows during rainfall and also improve bathing water quality at the local coastline.