The UK is experiencing prolonged dry weather and unsurprisingly, this affects our canals, rivers, reservoirs and groundwater supplies. Here are some of the more common questions put to us at this challenging time.
What’s the current water resources position?
Despite the prolonged period of dry weather the vast majority of our 2,000 miles of waterways are currently still open for boaters to enjoy as normal.
We are, however, seeing some localised issues. Particularly on parts of our network in the North West.
Although the reservoirs which supply our network in the North West were 100% full in April, the exceptionally dry conditions from May onwards has led to their rapid drawdown. A number of these reservoirs are relatively small and rely on regular inflows from rainwater during the spring and summer to add more water to them as usage increases.
The below average rainfall in recent months has meant that the reservoirs haven’t been able to recharge at a sufficient rate to provide for the summer’s boating in some places.
Currently there are localised issues on parts of the Leeds & Liverpool Canal, Rochdale Canal, Huddersfield Narrow Canal, the Lancaster Canal, the Peak Forest Canal and the Macclesfield Canal. See our stoppages and notices section for full details.
Elsewhere, on sections of the Grand Union, Oxford, Regent's and Caldon Canals, we’re locking up the gates at the end of the day to protect reservoir levels and enable backpumps to recirculate water ready for the following days boating.
We have been carefully managing the water feed from its own reservoirs, and maximising the amount of water it is entitled to take from the third party-owned reservoirs which feed both the Rochdale Canal and Huddersfield Narrow Canal.
However with no significant rainfall replenishing reservoir holdings we’ve reluctantly had to introduce restricted opening times at some locks and, in some places, temporarily closing sections of canal to boats.
The locations for the restrictions and closures are where we get most benefit for saving water, while allowing as much of the canal as possible to be open.
While the closures will prevent use of these stretches of canal by boats, they can still be used by anglers and canoeists and the towpaths will remain open for people - visitors and the local community alike - to enjoy. Boaters too can still make limited use of lock-free sections, or venture further afield to unaffected parts of the network.
Currently more than 90% of our 2,000 miles of waterways are available for boaters to enjoy as normal.
Elsewhere on the canal network we are monitoring reservoir holdings, feeder inflows and canal demands extremely closely to understand the risks to other parts of the network.
The rainfall that many parts of the country saw at the end of July has not significantly changed the situation.
We do not take the decision to close a section of canal lightly. It causes disruption to our customers and is a very costly exercise. We would not wish to reopen again only to have to close shortly after if rainfall does not continue. To provide our customers with stability we will only reopen once there is sufficient water in the reservoirs to avoid the risk of needing to re-close again in the same boating season.
The recent culvert failure on the Leeds & Liverpool Canal near Aintree, has only affected the bottom pound on the Liverpool side of the canal. It is not anticipated that this will have an impact on the reservoirs that feed the main summit section. The Trust have two river abstractions upstream of the culvert failure site that are being utilised to refill the canal towards Liverpool Docks.
The Leeds & Liverpool Canal often suffers from a lack of water resources. This is because the reservoirs that supply the canal rely on refill during the season to provide enough water for the whole boating season. These reservoirs just aren't large enough to provide enough water unless it rains during the boating season.
The Trust is currently exploring schemes to increase the amount of water resources available for this canal, however we have not yet been successful in finding an affordable, reliable option that provides enough water without having a detrimental impact on the environment.
All of our customers are located downstream of two river abstractions on the western section of the canal, and so they are not reliant on our summit reservoirs for water supply. June 2018 was a particularly dry month, where on average 0.5 Ml/d (around 2.5 lock fulls) was abstracted on a daily basis to meet all of our customer demands. On the busiest day 2 Ml (around 10 lock fulls) was abstracted, however there were also 6 days when no water was abstracted at all.
The total amount abstracted throughout June was 16 Ml/d (around 80 lock fulls).
The Trust has agreements in place with each individual customer, confirming the maximum daily amount that can be abstracted. We’re monitoring the abstractions closely during the current dry period to ensure there is no adverse impact on navigation. Where we judge this not to be the case, we are of course prepared to ask abstractors to cease taking water.
We are taking action now to conserve water levels in our reservoirs which in turn will provide a limited flow into the canals to minimise any ecological impact and protect wildlife. We will be monitoring conditions in affected areas because low reservoir and canal levels coupled with higher temperatures in summer months can cause problems such as algal blooms and low oxygen levels in the water. In some cases, we may have to consider fish rescues to move fish into areas we can protect.
Where we have closed canals at short notice trapping boaters then we would put in place measures such as an approved extended stay so that they don’t get reminders and for continuously cruising boats we would take this into account when assessing boat movement at licence review time. If you have any questions or concerns please get in touch with us on 0303 040 4040.
Our website is a great source of information on the latest water resource position and any boating advice/restrictions. Our water management team produces a monthly reservoir watch on the site, which gives details of reservoir holdings across the network. Or you can contact your local office to subscribe to notifications in a particular area.
Boaters have an important role to play in efficient water management. You can help us by:
We ask that marina owners, particularly those with hire fleets, help encourage boaters to act responsibly with water.
We also need all canal users to be vigilant about vandalism, as we have had some huge water wastages this year through vandalism. Please call the police if you have any concerns or witness vandalism.
The majority of water lost from the canal is through seepage and evaporation. The canal network is more than 200 years old and largely features a clay-lined canal bed which is not 100% watertight.
Sometimes, it is more cost effective to develop additional water resources (identify alternative sources of water) rather than tackle the most expensive leaks, especially when you consider that relining one kilometre of canal can cost well over £1 million.
While we have more water travelling through some locks than we would like, most of it remains within the canal system to feed demand lower down. In these cases, the lock leakage simply allows water to pass downstream, which is water that we would otherwise have had to feed via sluices and bypass weirs anyway.
Rest assured our technical teams look at these issues in detail and make decisions based on using our limited financial resources wisely.
No, our experience shows that where we’ve implemented restrictions of this kind in the past we’ve subsequently seen decreases in lock usage of 20-40%.
The loss of water from a canal pound due to leakage and seepage is the largest component of water demand on a canal system. Loss rates are at their highest during the summer, when soil is dry and water tables are low. The leakiest part of the canal lining is the top 15 cm (6 inches), because it is continually wetted and dried. It is also subject to holes or cracks formed by burrowing animals and wave action from boat propellers. So by increasing the operational level of a pound, especially in a drought, would greatly increase loss rates. During a drought, we actually aim to run pounds as low as operationally possible to reduce losses.
We have a rolling programme of surveys to monitor the capacity of our reservoirs and these show that, generally, over a number of years siltation hasn’t been a significant problem. It is also generally accepted within the water industry that the removal of silt from reservoirs is considerably more expensive than creating new resources or reducing demand elsewhere. This cost means that reservoir dredging is very rarely cost-effective and, particularly so in this case given the results of our reservoir monitoring.
As well as responding to unfolding droughts, we also take a more strategic approach to managing future water resources. Our water management team is responsible for assessing the resilience of water supply and advising the business on the potential impact of proposed canal developments (e.g. new marinas) and investment required to supplement water resources.
The Trust reserves the right to object to or decline canal development proposals on the basis that they may have an unacceptable impact on the existing water supply. Unfortunately, we can never give absolute assurances to our customers about having enough water to get through every drought, regardless of the extent, duration and severity but we will do whatever we can to keep as much of the network as possible open.
You can also download our North West positioning statement here which elaborates on water levels, specific restrictions and how everyone can help to follow our THRIFT camapign to conserve water.
Last date edited: 15 August 2018