River Darent in the current Heatwave and Drought

13th August 2022

River Darent in the current Heatwave and Drought

River Darent in the current Heatwave and Drought

As you may already know, the Darent is one of only 210 chalk streams in the world, and one of only 161 in England. Chalk streams are of great ecological significance.

There are a number of projects across the Darent Valley that work to protect the river and its environment. Currently low water levels in the Darent are of great concern, and these low levels have led to vegetation appearing more obvious.

It is, however, of huge importance that the river retains its aquatic plants which are an essential component of a healthy stream providing cover for fish, and habitat for macroinvertebrate communities on which fish feed. Certain plants also have a role in filtering bacterial and algal matter from the water which ensures that the gin clear water associated with chalk streams is maintained.

The current heatwave may cause oxygen levels in the Darent to plummet causing severe distress to fish.

The Environment Agency is aware of these problems and the details below, provided to one of the local Darent Groups, explains their mitigation plans:


Fish rescue

We are currently in full incident response mode and have doubled the fishery duty officer roster to deal with the elevated numbers of incidents occurring across the area. The Darent will take priority regarding attendance and deployment of aeration kit. Fish rescues are the last resort, to date we have carried out three rescues, none of which have been on the Darent, however we are prepared to do so if required.

We have received multiple calls about low flows on the Darent of which some have included fish in distress. We have been operating a surveillance plan over several weeks which has confirmed low flows but has not yet confirmed distressed or dead fish. The river has been identified as being of high risk and surveillance will continue. We have responded to a fish kill; however, this was assessed on site as being a consequence of a pollution.

With regards helping we would welcome and encourage your support reporting any signs of fish in distress so we can investigate and respond to these reports.

To do so, please call our emergency number on 0800 807060 providing as many details as you can. Also, if you could promote the awareness and use of this number through your forums that would also be of great help.

Augmentation/borehole data

We are currently holding weekly meetings to consider, if and when to operate our augmentation boreholes at Lullingstone, Eynsford and Farningham. We have been reviewing on-site reports of flow conditions and fish in distress from EA staff and members of the public; groundwater level flow data from our gauging stations at Otford, Lullingstone and Hawley; and additional manual flow gauging at six intervening sites (Lullingstone, Eynsford, Farningham, Franks Hall, Frog Island and Hawley). A review of the effectiveness of the augmentation in the mid-2000s has led to a change in approach intended to limit its use to safeguard the integrity of the river habitat.