Retford Information Page

Overview

Retford Beck Information Page

Map showing who looks after each of the watercourses across Retford

Geography of area

Retford sits in the low-lying River Idle valley, where the Idle flows through the town from south to north. Retford Beck is a tributary of the Idle and arises in the high ground to the east of Retford. Both the River Idle and the Retford Beck are designated Main River. 

Annotated Aerial view of the lower Retford Beck catchment. Arup (2021). 

East of Retford, the Retford Beck has two separate open channels. Each flow through farmland before entering the eastern outskirts of Retford at Grove Lane and Blackstope Lane. Each tributary flows in separate culverts beneath the Sheffield to Lincoln railway, followed by a short length of open channel. Flowing parallel to Grove and Blackstope Lane each respective channel re-enters culverts before combining upstream of the Chesterfield Canal, where the watercourse passes beneath the canal in a syphon. The Retford Beck remains in culvert beneath the town centre until it discharges into the River Idle. 

Flood History across Retford

Flooding from the Retford Beck is the main flood risk to properties upstream of the Chesterfield Canal, around the Blackstope Lane and Grove Lane areas of Retford. In recent years the area has been impacted by flooding with events occurring in 2000, 2007, 2012, 2015, 2018, 2019 and most recently from Storm Babet in October 2023. Internal flooding to properties was not reported in the 2012, 2015 and 2018 however.

In July 2007, 100 properties were flooded in Retford from both the Retford Beck and the River Idle. 29 properties suffered from interior flooding during November 2019. The majority of properties were in the Blackstope Lane and Grove Lane area. The main cause was very intensive localised rainfall, causing surface water flooding and raised the levels on the Retford Beck beyond the bank-full level. 

Most recently, during Storm Babet in 2023 the River Idle and surface water flooded 125 properties in the Ordsall and Thrumpton area as well as critical infrastructure. The Carr Dyke, a drain managed by the Internal Drainage Board (IDB), flooded 23 properties due to possible interactions with the River Idle. The Retford Beck also flooded 22 properties internally and flooded 4 externally.

Street photograph of Grove Lane in the October 2023 flooding, Environment Agency 2023.

Recent operational response

As a Category 1 responder the Environment Agency (EA) have a structured incident management plan, with duty staff available 24/7. Weather and environmental conditions are constantly monitored to support the preparedness of response and prioritisation of the most high risk communities.

The EA field team undertook proactive patrols checking all assets prior to the peak river level on the Idle. On the morning of Sunday 23rd October, two Severe Flood Warnings were issued for the River Idle at West Retford and Ordsall and the River Idle at Retford, Eaton and Gamston. These were removed on the Sunday afternoon. The EA coordinated with the Fire and Rescue service to evacuate 238 properties.

The EA responded to flood incidents on Grove Lane and Blackstope Lane during Storm Babet in October 2023 and Storm Henk in January 2024. Field staff used pumps on Grove Lane to increase the flow rate through the culverts to the Chesterfield Canal syphon. Due to the significant build-up of sediment in the syphon, this procedure was found to be less effective at draining the flood water.

The incident management plan for the Retford Beck was updated and during the Storm Henk event, the Beck was pumped directly into the Chesterfield Canal. This new system was more effective at managing the flows from the Grove Lane and Blackstope Lane catchment and no property flooding occurred.

The incident management plan is being further improved to address the northern arm of the Retford Beck on Blackstope Lane. The syphon under the Chesterfield Canal is also programmed for clearance works to restore the capacity during the summer of 2024.

Scheme history

Retford Beck

An initial assessment and Business Case for an upstream flood storage reservoir was developed by Bassetlaw District Council in 2018 and passed over to the EA in late 2019. The EA then continued to attempt a viable flood storage reservoir scheme for the Retford Beck.  

At the flood risk information event held in November of 2022 at Retford Town Hall, EA staff shared that the reservoir scheme was becoming difficult to progress due to an increase in the overall costs. All EA schemes must follow the Treasury Green Book rules for investment, where an evaluation of cost against economic benefit is mandatory during the appraisal process.  

Since the public event in November 2022, the economic assessment of the Retford Beck Flood Alleviation Scheme was updated and unfortunately, due to rising cost estimates, the total project cost outweighed the economic benefit of the proposed reservoir and made the scheme unviable. 

EA and partner ongoing and future work

Retford Beck:

Following the decision to no longer proceed with the reservoir Scheme, the EA and Partners have changed their focus and other works are being undertaken to manage flood risk from the Retford Beck. 

Retford Beck Culvert renewal and replacement

The existing Retford Beck culverts beneath Blackstope Lane and Grove Lane are in poor condition and require repair. Ahead of commissioning this work, fluvial modelling has been completed and demonstrates a positive change in flood risk. The EA are commissioning utility surveys which will be undertaken from 27 May 2024. Road closures will be in place along Grove Lane and Blackstope Lane during the surveys, which are expected to last for 3 weeks. The surveys will inform the design and business case. The current programme targets business case assurance in 2024 and, if assured, construction to start in 2025. 

The EA are developing a Flood Warning Service for properties affected by the Retford Beck. This service will provide advanced warning when flooding is possible. The Flood Warning Service will use weather forecasts and live river level monitoring to trigger alerts and warnings. A new gauge is being installed this summer to Retford Beck North, and we expect the service to be ready by the end of 2024. 

Idle:

We are assessing high level options which could have the potential to alleviate flood risk from the River Idle. These will be economically analysed to understand whether there are any cost-beneficial options which can be delivered.

Carr Dyke:

A meeting was held with the IDB on the 28 March 2024 to discuss what flood alleviation measures may be viable to alleviate flooding to the properties on Darrel Road. A list of potential EA options has now been agreed. However, to understand whether these options will be technically feasible, and will provide the required flood risk benefit, we must first assess them using hydraulic modelling.

The Carr Dyke is the responsibility of the IDB and its function is to convey land drainage run-off from the field adjacent to it. However, when the River Idle is in flood, the flows from the river overwhelm it and the surrounding area. Due to these interactions of the Carr Dyke with the River Idle we are working in close partnership with the IDB to investigate what options can be developed and progressed to address the flooding at this location. The IDB are currently considering what options they can propose in the context of the longer-term management of the River Idle.

As the Carr Dyke is not a Main River, it is not currently included within our EA hydraulic model of the River Idle. Therefore, we have commissioned additional modelling of the Carr Dyke to better understand the flooding mechanisms between the two watercourses. Once the baseline modelling of the Dyke has been completed and integrated into our River Idle model, the options which were identified during the meetings will be tested. This process has now commenced, and surveyors have completed the initial survey of the Carr Dyke, which is required for the modelling. Once the options have been tested and technical feasibility has been established, economic assessments will be carried out to understand whether any of the options are economically viable, in line with the Defra Partnership Funding Rules.

While awaiting completion of the hydraulic modelling, various works 'on the ground' will be carried out this year by the EA. Our field team will be undertaking localised earthworks this summer to reinstate the level of the area identified as a 'low spot' on the bank of the River Idle. We will also be undertaking targeted 'de-silts' of the River Idle in specific sections where silt has accumulated as well as undertaking tree and vegetation maintenance. Scoping site visits have already been undertaken to identify the works needed for the low spot, de-silts and tree works and we are currently writing up the risk management paperwork needed. De-silting works along the Idle will also commence this summer. There are various constraints outlined in the environmental legislation we must adhere to which will also dictate the timings. Tree works will be undertaken this autumn/winter once bird nesting season has finished. No additional hydraulic modelling is required for these works to proceed.

General Bassetlaw Information Pages 

This page provides information on flooding for Worksop specifically. To find out more information on flooding in Bassetlaw in general, please follow the links below:

Bassetlaw District Information Page 

Worksop Information Page