Following a dramatic upturn in major weather events experienced nationwide in recent years, the Environment Agency sought to protect homes in the Enfield area from residential flooding by constructing a substantial barrier to the eastern edge of Enfield Golf Club. Whilst this was no doubt excellent news for the local residents, with 192 homes having been ruined by flooding in October 2000, those with a golf membership had reason to be concerned. This is due to the fact that Enfield Golf Club sits on council-owned land that is long-term-leased to the club, and had been designated by the Environment Agency to become flood plains as part of the £15.3 million scheme.

A large embankment housing a flume (flow restriction) was constructed at the point where the Salmons Brook watercourse meets the northern boundary of the golf course. In high-volume storm events, water flows that would have previously posed potential risk of residential flooding downstream are reduced, causing the river water to back up and flood the golf course rather than precipitate damaging surges of water further downstream.

Although plans for the flood remediation scheme had been in the works since at least 2005, it wasn’t until 2012 that golfers and other concerned local residents successfully lobbied for amendments to the scheme to reflect the potential damage this flooding would cause to both the course and the club more generally. Consequently, the Environment Agency’s Flood Risk Management Technical Specialist Steve Whipp proposed that drainage improvements to the course be integrated into the scheme in order to minimise any disruption and damage to the course and club following flood events.

Liaising closely with the Environment Agency, the Council, and of course the Golf Club, Turfdry designed a comprehensive remediation scheme. This saw a high specification Turfdry Drainage System installed on affected fairways and the 10th green, with the ambition not to prevent flooding, but to return the course to play as quickly as possible following high-volume storm events.

The challenge of this endeavour was driven by the topography of the course – in particular, the way the fairway ground levels rise consistently when approaching Salmons Brook from both sides, thus creating a ‘bowl’ effect that would trap floodwater on the affected fairways. A successful drainage scheme would therefore have to account for these ground levels to ensure proper de-watering of the low-lying land adjacent to the brook.

Conventional plastic pipe drainage must be laid at a minimum fall of 1 in 200; this ensures that any sediment that enters the drain via the perforations can be ‘flushed’ away by the natural transit of water within the system. However, this can prove problematic when the natural topography of the land does not allow for such a steep gradient on the drainage pipes. This was the case with the Enfield Golf Club flood remediation scheme: as the drainage system had to discharge collected water into the Salmons Brook watercourse. As the level of the system’s outfall was limited by the normal water level of the brook itself; this did not allow for the required 1 in 200 gradient for plastic pipe drainage (as it would have been below the normal water level of the brook), presenting a major problem for the scheme’s design.  

Turfdry’s unique Hydraway Sportsdrain is a highly-engineered alternative to conventional plastic pipes, which – thanks to the laboratory-proven clog-resistance of its geotextile layer – does not allow sediment to enter the drain. This means that the minimum 1 in 200 gradient requirement does not apply, allowing Hydraway to provide effective drainage of sites when plastic pipe systems cannot. In fact, Hydraway has long-term (>20-years and continuing) proven effectiveness in UK sites, when installed at zero gradient.

Combined with the product’s consistent track-record of delivering exceptionally quick drainage performance, Hydraway therefore represented the only feasible option for effective drainage of the flooded fairways without the use of a pumping system.  

The trenches for the lateral drains were installed using a laser-level to ensure the rising ground levels towards the brook did not impact collected water’s ability to discharge from the system; these lateral drains were connected to non-perforated main carrier pipes, which outfall into the watercourse via non-return flap-valves, which prevent water from backing up into the system when the brook’s water levels are high.

The performance of the drainage system over the wet winter of 2014 - and in particular the drainage installed on the 10th green, which was commonly cited as the wettest green on the course prior to the drainage installation - compelled the club to quickly contact Turfdry to design and install its greens drainage system on a further seven greens in 2015. 

The satellite survey of the course initially undertaken for the 2014 works again formed the foundation of the design work, and was supplemented by a number of site visits to ensure total sensitivity to the demands of the club, and the issues present on the course. Despite some classically challenging British weather, the installation was carried out quickly and efficiently, with a subsequent site visit revealing very positive opinions regarding the speed and tidiness of the works - General Manager Paul Beresford-Green noting that "many members have complimented the tidiness of the greens work."

Indeed, the club's continued delight at the efficacy of the Turfdry Drainage System, and the strong working relationship established between the club and both Turfdry's management and installation teams, a further six greens and an additional fairway were drained by Turfdry in Spring 2017.

Despite the dramatic trend towards ever-wetter winters, North London has generally suffered fewer flooding events in the years since the weir construction – primarily as a consequence of longer periods of sustained rainfall, in contrast to high volume downpour events. Nevertheless, the Environment Agency’s residential flood prevention scheme was activated for the first time in early 2021. As per its design, this deluged the 1st, 2nd, 9th, 10th, 11th, 12th & 18th holes, leaving them flooded up to 3 feet deep in places.

Within 24 hours of the flood surge, the Turfdry Drainage System using Hydraway Sportsdrain had cleared all of the floodwater from the course – as shown by the photos kindly shared by Head Greenkeeper Dane Watts, taken on the 14th & 15th January.

Although golfers have been glowing in their praise for the effectiveness of the Turfdry Drainage System in dealing with more regular high-rainfall events, many were still sceptical that it could overcome the ‘bowl’ effect of the areas adjacent to the brook, trapping floodwater on the fairways for some considerable time after the water levels dropped. This would not only have restricted the course’s immediate playability, but would also contribute to compaction and challenges for healthy grass-coverage.  However, thanks to Hydraway’s effectiveness even when installed at zero gradient, the laser-graded design for the drainage system ensures rapid de-watering of even challenging topography, and returned the course to a playable state the very next day.