Thursday, 7 November 2019

Water - are we using too much?

Is this a river or a long narrow pond?

Have you looked at the River Cam lately? It is more like a long narrow pond than a river, the flow is so slow, even after all the rain we had in October. The Environment Agency water situation reports since at least May rate it as ‘Exceptionally low’ which means, based on historical flow, it has been better than this 95% of the time. However in terms of rainfall the current drought is not exceptional - certainly not as bad as in 2010/2011.

The Cam is fed from chalk streams fed from the same aquifer that is used to supply our water. The groundwater levels in this aquifer are also exceptionally low and long sections of the streams have been completely dry at times. This is a serious problem for the natural environment: there are impacts on fish, insects, birds and plants in and around the river and its tributaries. The Environment Agency has described this an 'environmental drought'.

This is why I am organising a Transition Café night on 20th November about water. We will have a number of expert speakers to explain the situation and then we will discuss what we can do about it. Please come if you can. The problem is partly caused by climate change and there are striking parallels to climate change in how we might manage it.

A water crisis forum met on 5th Nov. instigated by Councillor Katie Thornburrow
The problem seems to be a combination of increased water use due to increasing population and increasing variability in weather, related to climate change. We have just had two dry years in a row and a third would lead to very serious impacts. These matters were discussed at the water crisis forum set up by councillor Katie Thornburrow, with representatives from the Environment Agency, Cam Valley Forum, Wildlife Trusts, Cambridge Water Company and others. I gather the mood was sombre.

There are several organisations involved in managing our water catchment:

  • Cambridge Water supplies the water
  • Affinity water (to the South) and Anglian Water also have some boreholes in the same catchment and some farmers also take water directly from the same aquifer,
  • Environment Agency controls everyone’s licences to abstract water
  • OFWAT scrutinises the water company’s investment plans and water charges

Cambridge Water has plans to reduce leakage (currently 15%)
The amount of water that Cambridge Water takes is what we use plus leakage. They could reduce leakage and they have plans to do this, though they are already better than average. (You can find leakage and other statistics comparing water companies at Discover Water ). Other solutions are likely to involve a great deal more investment – for example importing water from further afield. This would mean increasing bills and OFWAT would have to permit this.
Chart showing water usage and availability (dry year annual average) showing plans to reduce leakage. From Cambridge Water's latest draft Water Resources Management Plan

We could reduce the amount of water we use at home.
We could reduce the amount of water we use. Cambridge domestic customers are about average for this - 133 litres/person/day for households on a meter, more for unmetered households (also from Discover Water). Our local plan requires that new homes are built to use no more than 110 litres/person/day (based on typical washing and toilet use). This is not hard – it is mainly a matter of efficient toilets and showers (for more info see How much less water do modern houses use). We can actually do a lot better than that if we try – which is one of the things we will discuss on Wednesday. Why don’t you take a look at your own water bill to see what you use?

Is the way we pay for water fair? It is incredibly good value.
It would also be interesting to look at things like how we pay for water: is it fair that about a quarter of households do not even have a meter? However water is incredibly good value even if you do have a meter: here in Cambridge a typical day’s use costs 33p (0.25p/litre including sewerage charges). Should we pay a flat rate or should we pay more for higher levels of use?

Anglian Water is short too - their plans include desalination.
Where can we get more water? Trading water with Anglian water will not help – they are stressed too. The Environment Agency is reducing some of their licences and they have a growing population. They actually have plans for a desalination plant at Felixstowe to supply extra resource. (See their plans here.)

Could we reuse our water, or trade with sources further away?
Currently, although we take our water from the aquifer under the Gog Magog hills we give our used water (i.e. our sewage) to Anglian Water to treat. Anglian Water are also considering water reuse schemes, where the sewage is treated to drinking water standards and reused rather than giving it back to the environment. Could Cambridge ask for our treated water back? Or should we build water transfer schemes from much further afield?

Cape Town experience shows what can happen if we ignore the problem.
If we put off fixing this problem, could we end up with a situation like the Cape Town drought? Earlier this year they were days away from standpipes in the streets, and were rationed to no more than 50 l/p/day. The near disaster was predicted and avoidable.

Water shortage is a lot like climate change.
Our water situation has striking similarities to the climate change situation and our use of energy.

  • There are potentially very serious impacts on our wellbeing as well as that of the natural environment, but it is hard to say exactly when they will bite.
  • Our options for handling it range from expensive new infrastructure (which also takes time to build) to low cost individual behaviour change.
  • Our water bills are currently too low to motivate many people to be careful, but increasing bills (for example to pay for new infrastructure) would bring hardship to some.
  • Individually we cannot solve this – we need to act as a community.

The first step, however, it is to realise we have a problem. So please come on Wednesday 20th November and find out.

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