Following the flooding events of 2014 in Long Marston, Herts County Council (HCC) was engaged to investigate the flooding and produce an Investigation Report under Section 19 of the Flood and Water Management Act 2010. This and the accompanying technical assessment report can be found on the HCC website :-
At the same time, a Flood Working Party (FWP) was formed to look at the flooding issues across the Parish. The FWP which is Tring Rural Parish Council (TRPC) led, comprises :-
Peter Myrants (chair)
and can be contacted at firstname.lastname@example.org
The FWP has been working closely with HCC since 2014 to explore options to try to mitigate flooding in Long Marston and surrounding areas. Whilst progress has often felt laboured over this period, there has been some recent progress and good news….
A public consultation meeting was held on18th July 2017 at Long Marston Village Hall, where HCC presented an Options report, produced as a result of further investigation by the Technical Consultant, following the initial Section 19 Flood Investigation Report.
An update was provided on all the options (to mitigate / reduce flood risk) explored in the report. Also, a timeline video was played of the flooding events of 7th February 2014, as simulated by a hydraulic model which has been constructed using a variety of amassed technical data and anecdotal information received from Parishioners.
Whilst the majority of options presented were not viable due to their high cost over benefit, HCC announced that they had been successful in their bid for funding from a new government Natural Flood Management (NFM) pot by securing £250k for two pilot projects across the county. Given the close working relationship established between HCC and the FWP and the focal point that the FWP has provided, HCC selected Long Marston as their first choice, with Harpenden being the other pilot / case study.
HCC refers to the new high profile NFM project as a partnership programme, over 3 years, which will involve HCC, FWP and the Environment Agency (EA) with support from TRPC and its Parishioners. For TRPC this represents a significant and unique opportunity for funding (approx. £150k), that a village the size of Long Marston would otherwise never secure, as was highlighted in the Options Report.
HCC stated that there is no magic bullet solution for flooding in TRPC but they hoped that NFM could implement several low cost schemes to mitigate or reduce the impact of flooding.
In parallel with the NFM programme, the FWP continues to look at the broader flooding issues across the Parish, expanding the focus beyond Long Marston to the other villages. The FWP plans to produce some practical guidelines and information to help Parishioners in the event of flooding.
The TRPC and FWP continue to look to Parishioners for their active interest and support, to ensure the success of the NFM programme and the FWP’s broader engagement across the Parish.
We especially look for the support and co-operation of land owners to gain access to their land, in order for any of the NFM initiatives to be successful.
Updates from the FWP will be reported in the Village News and here on the TRPC website.
NFM Update – Sep 2019
Investigation of the potential for flood storage in the village recreation ground (Option 7 in the Options report)
As part of investigating the feasibility of Option 7 infiltration tests were commissioned and carried out in the recreation ground. Three trial pits were dug to measure the potential for infiltration using the industry standard BRE 365 methodology. Two boreholes were sunk so that groundwater levels could be measured and then monitored over a period of time.
These test boreholes are still on site and will be monitored into winter 2019/2020.
The test results showed that infiltration is not a viable option due to a thick band of clay, which is typical of the Long Marston area. This information indicates that any surface flood water temporarily held back on the site as part of a flood risk management scheme would not naturally drain away.
However, the ground conditions would be favourable for temporary storage of water in flood conditions. The clay layer would mean that water would not seep under a structure, such as a bund. However the challenge will be to find a viable means of draining the area.
The potential to put a flood risk scheme in place would also be dependent of being able to design a scheme that was financially viable and that did not have an adverse impact on use of the area.
This will be reviewed after the winter period of borehole monitoring in conjunction with the results of the highways drainage surveys that have recently been carried out.
Investigation of improving function of Tring Bourne and Ashen Brook (Options 2, 9, 10, 11 in the Options Report) and looking at the potential to increase in channel storage in the vicinity of Lukes Lane.
Following on from the Nature and Nurture event on July 4 2019 and subsequent conversations with the E.A., a feasibility and design study is being finalised for procurement. This incorporates the options 2, 9, 10, 11 from the 2018 Options Report.
In addition, a second project is being included in the contract looking at an option to incorporate some woody slow-the-flow interventions in the watercourse upstream of Long Marston.
It is anticipated that the Feasibility will be completed early in 2020 and if anything is feasible, engagement and design completed by Spring 2020.
A ditch/watercourse and Riparian Workshop Training event is being planned for November 2019 with the EA. The primary goals from this workshop are to obtain hands-on training and knowledge that can be imparted to others plus a ditch maintenance plan.
Chapel Lane – Road Lowering Investigation
Detailed design and costings have been undertaken by the Highway term contractor which includes lowering of service pipes. Once final costs have been collated, the project will be assessed to see if it remains feasible, with HCC conducting a thorough stakeholder engagement process.