Dredgers in Paradise

One of the dangers of best-kept secret rivers is that they are more easily trashed. I have long known this, and more than once before have had to open up on the name of a beautiful stream that I enjoy walking and fishing in order to shout loudly how important it is.

I’ve not done this in New Zealand before, however, have not ever felt it was my place to. And I know that Kiwis, fishing guides especially, don’t like the names of their secret spots broadcast far and wide. So, I’ll keep the name of this place quiet for now – if you know it, you’ll know it – at least until I can find out more about the reasons behind what I saw yesterday.

Because yesterday, I felt like giving up. I was totally in the dumps. The struggle to champion the cause of pastoral spring streams (chalk streams being in that group, and at the very apex of pressure caused by humans) feels too much like an uphill one at times.

I’m on a tour of New Zealand with Simon Cain – also a passionate river-restorationist who I have known since 1991 – showing him all the unspoilt spring-creeks I have been going on about for so long, the rivers I like to model river restoration ideas on. I told him the stream we were going to look at was one of my favourites: “It’s kind of like the upper Frome,” I said. “Only maybe a 13th century Frome.”

You could pick all sorts of holes in my comparison. There were no mills on this stream. There are no mountains to the side of the Frome. But it painted a picture. And indeed this stream has also worn the impact of farming quite heavily in places, over the years. It is abstracted by pumps. One farmer on it makes no effort whatsoever to fence out the livestock and the riparian edges in that reach are nibbled and puddled bare. The very headwaters, which were once a marsh supporting the base-flow, have been arterially straightened in the past.

But somehow the river was still just lovely. And I have often cited the lowermost farmer – when chatting to other farmers, many of whom are not that happy about the new NZ law compelling the fencing out of livestock (it is causing problems with overgrowth of rank marginal vegetation) – as having managed the riparian strip to perfection ever since I had known the place and long since before the new law: a fence twenty to fifty meters back and very occasional grazing on the stream side. He had presided over a true spring-creek paradise.

Which is why I suspect the farmer here is not to blame. Why, having been apparently perfectly happy for many years with the co-existence of his farming and his spring-fed stream, would he suddenly take a hatchet to the latter and hack it to bits?

We noticed the silt on the bed as soon as we arrived, noticed spoil on the bank by the first pool: rocks and stones and dusty, ex-riverbed the colour of light earthenware under an unnaturally vivid green flush of nettles and docks and thistles: all the stuff that loves the arrival of river-bed nutrients on top the of the floodplain where they don’t belong.

My thought was a resigned “that’s a shame”. We were near a bridge and I know farmers do get a bit heavy handed with the digger around bridges, in a (usually misguided) effort to create greater conveyance of flow.

But then around the next bend we saw more of the same, only the digger had really gone to town here, pulling out the bed and inside point-bar, dumping it all up in the side. The work had been done only a few months ago and already the stream was notching its way back upriver. Already the stream – in other words – was demonstrating the utter futility and pointlessness of the works, because it was now eroding really badly, with the banks slumping in and drastically undercut because of the excessively steepened gradient.

This continued for bend after bend. Apparently as far as we could go and further.

I felt too miserable after a mile or so and we turned back.

Then I remembered the photos I had taken here in 2020, expressly to capture the morphological features of the stream: the meander shapes, the relationship between the water surface and the flood-plain, the gently undercut banks and point-bars. All of which were now screwed. I hunted back on my phone to February 2020 and tried to line up a few before-and-after images. But I struggled to find the correct alignment between the stream and the hills: at least until I realised that not only had they dragged out the bed of the river, they’d tried to cut the meanders out too.

I was still just about thinking it was the farmer’s work and I was trying to fathom the “why?”. I was thinking: “They’ve had massive floods and done all this in an understandable, but misguided effort to drop the river back inside the banks.”

We slumped back to the car and in an effort to cheer both of us up I said to Simon that we’d drive up the valley to another bit I know. Only when we got there Simon looked out the window and said: “They’ve fucked this too. Look at all the gravel!”

And indeed, “they” had. Whoever “they” are.

By now I was thinking: this is the work of a flood defence department. Our own versions did all of this and more in the UK and Ireland. Only flood defence departments are this dim, careless and – I hate to say this but – entitled. I’ve thought about that last word, whether it is justified here, as the first two surely are. And I think it is, because when you go in and radically alter an ecosystem like a spring creek, it is surely beholden on you to understand what you are doing and carry out the works so that they achieve the desired outcome and not simply wanton destruction?

NZ’s spring creeks are globally very special. There just aren’t many rivers like these and most have been messed around with. NZ’s spring creeks have (thus far!) been modified less than most and some not at all. These streams should be seen as a national treasure, not drainage channels.

Later, asking around in town, we discovered that there had indeed been floods. The golf-course had been underwater and so had stream-side houses … miles downriver of the spring-creek vandalism, mind. Riparian property where a river belongs. It all made sense.

Only a flood defence department would steepen the gradient upriver in an attempt to alleviate flooding downriver. Only a flood defence department would make far worse the very problem they were trying to fix.

The river will now try to tear itself apart in order to win back the material it needs to put itself back together. As it does so, the water will travel more quickly, and downstream floods will be more aggressive: they will rise faster and bring with them way more mud, silt and stones.

Rivers flood. The only way to control flooding is to control where it happens. You can’t stop it. Allow it to happen in certain places in an effort to ensure it doesn’t in others. This stream has a two-stage form anyway, with secondary terraces way back from the main channel: you have to let it flood out to these or you will send all the water in even more of a hurry to the very property you are trying to protect.

One optimistic note: this stream will self-heal. Unlike chalk streams, it has the energy and the material to do so. Provided it is left alone. Which is now a very questionable proviso, because the notching and erosion will unleash a process which will appear in the minds of the men who did the work, to justify it in the first place.

And so we struggle on “boats against the current, born back ceaselessly into the past”.

February 2020
January 2023: not quite the same spot but note the new channel to straighten the course, the notching, erosion and bank collapse.
February 2020
January 2020: note the straightening and the height of water against the bank on the r/h of image: maybe 40 cm lower.
February 2020
January 2023: I had trouble lining this one up, until I realised the bright green bit used to be the river, and they had taken the meander out.

More pictures of the destruction:

The long Christmas read: what do we mean by sustainable abstraction?

We spent for ever trying to pin this one down as a foundation of the chalk strategy and finally settled along the lines of: abstraction should not reduce chalk stream flows by more than 10% from natural at Q95 (generally late summer), albeit there’ll be places where a less stringent target is acceptable (lower reaches of larger streams that are very heavily modified) and also there will be places where – as targets are neared – habitat improvements could arguably make more difference to ecological health than the last few increments of abstraction reduction.*

(*worth mentioning here that there is an inherent issue with flow targets in chalk streams: where do you measure the impact, given it will vary as you go upstream? Chalk Streams First has proposed abstraction as a % of recharge figure (10%) as a simpler way to limit impact, partly to overcome this issue: this will become relevant further in to this post)

Now, the eminent hydrogeologist Rob Soley has opened Pandora’s sustainability box again and is questioning whether, in the environmental ambition of the draft regional plans, the concept of sustainable abstraction has lost its holistic inclusion of cost and human need and is too narrowly focused on flows alone. This is an important debate and it needs to include all of us. So, this will be a long blog post but a worthwhile read, I hope.

For a while after I joined the WRSE environmental panel advising on the draft regional plan I was completely lost in a sea of acronyms and diagrams of water resource scenarios that looked like the wiring plan of a 1970s Fiat. I didn’t really know what anyone was talking about.

But then one day Tom Perry from the EA produced a spreadsheet of proposed reductions in abstraction for the chalk streams of the Colne and Lea catchments and for me the discussion suddenly morphed from the abstract to the concrete. This was where wiring diagrams met the real world and I realised what a game-changer the regional planning process could be. 

For the first time we were looking at evolving our siloed, localised, groundwater- and gravity-dependent water-supply systems – which inevitably exert a large environmental impact where the supply/demand balance is most out of step – towards better interregional planning, transfer schemes, water recycling and future desalination. 

And not before time. As long ago as the mid 1800s a miller on the River Gade, whilst arguing with the Grand Union Canal and London Spring Water companies about the impacts their abstractions had on his stream* had suggested that the long-term sustainable answer to London’s water supply deficit was to transfer water from north Wales, where it rained a lot and where there weren’t many people. 

(*Impacts they denied, of course. Worth noting too how the GUC and LSWC recruited the best scientific minds of the day to advance their case and argue that, for example, the water came from an infinite subterranean source incapable of exhaustion and completely isolated from the surface!!)

Here we were, 172 years later, finally thinking about the miller’s sensible, but ignored, idea. Though it sounded dryly bureaucratic, I realised the national framework planning process had the potential to bring about truly significant improvements to our really heavily abstracted chalk streams. The deficits to acceptable flows identified by Tom and the EA fairly closely matched those indicated by our Chalk Streams First modelling. We were on the same page and we were talking about truly meaningful reductions. 

But Tom’s first schedule really only covered the chalk streams. Later, when I saw the more global figures for all rivers and waterbodies, I started to worry in the other direction: they seemed so massive. Not from a purely ecological point of view, of course, so much as from a practicable point of view. How on earth would we deliver reductions that amounted to almost 2,500 Ml/d – the more ambitious of the potential scenarios – in the WRSE region alone? And could leak reduction and demand management really take up all the slack until 2050?

To put that 2,500 Ml/d into perspective, Abingdon reservoir could potentially add 400 Ml/d to our regional output. 

To put that into another kind of perspective, the total deficits to acceptable flows across ALL of the 55 chalk-stream catchments which we identified in our CaBA chalk stream A%R report amounted – according to the A%R assessment methodology which is not the same as the EA flow-based methodology – to only 399 Ml/d (excluding the lowermost Lea and Colne) and even that included about 100 Ml/d from chalk streams in the south west and eastern regions. Overall, we had deliberately surveyed most of the chalk streams which we suspected to be under the greatest stress.

The danger seemed obvious: Ofwat would look at the cost of these ambitious scenarios, deem them unaffordable and throw the chalk stream baby out with the “enhanced scenario” bathwater. Although I sat on the WRSE panel, I nevertheless responded to the first iterations of the draft plans, stating the importance of prioritising these proposed reductions so that we didn’t mix the “essential” up with the “to-no-great-gain” and the importance of planning / delivering the reductions in such a way that the investment added up to conspicuous improvements. 

The last thing we want is to expend a great deal of effort and money to no great or obvious effect, undermining the case for environmental restoration in the first instance. It would be perfectly possible to. Arguably this is what has happened thus far, where abstraction reductions have been made in a piecemeal way, often offset by increases within the same catchments, so not actually amounting to net reductions at all, consequently allowing a narrative to develop that abstraction reductions don’t really yield much of an increase in river flows, or not one that you’d notice, or not one that is justifiable given the cost. 

Recently, Rob Soley has been leading a bit of a kickback campaign questioning the sense of the proposed reductions in the national framework. Of course Rob’s concern may include a worry that overblown / poorly planned abstraction reductions could run the danger of ruling ALL abstraction reductions out of court: but mostly Rob is worried about turning our backs on a valuable water resource (the chalk aquifer) at exactly the time when water resources are coming under greater stress from a changing climate and when the cost of living is putting a squeeze on the nation’s finances: all to what Rob argues will be arguably of little ecological benefit. 

So, I instinctively want to disagree with him, but I find myself partly agreeing with him, even if we are coming from different points of view.

Rob gave a webinar presentation on this subject last week to the Geological Society’s groundwater forum.  The audience was – as you may have guessed – comprised almost entirely of hydrogeologists. There was much agreement with Rob’s argument and so the kickback will be well supported by experts, I suspect. You can watch the presentation HERE, but I’ve written a layman’s précis of the argument in blue below. 

Even though Rob apparently argues for something like the exact opposite of what we (ie. Chalk Streams First) have been arguing for (the restoration of flows to headwater chalk streams and the chalk-stream tributaries of systems like the Colne) I am very keen to find common ground, for the reasons expressed above: unless we get these abstraction reductions right – properly planned and judiciously delivered in the right places, at meaningful scales and allied with habitat and water quality improvements – we will undermine the case for them altogether and we’ll be back at square one. 

This is a very finely balanced argument: for the first time ever the regulators are planning a national re-plumbing that allies public supply resilience with environmental restoration. Fantastic! But it’s expensive work and we have to get best value from the investment. And we also have to make a powerful case for the continuing inclusion of environmental restoration in the definition of best value: it will fall out the door if we spend money unwisely.

In an effort to find that common ground I have made notes (in red) against Rob’s argument (in blue), pushing back here and there but agreeing where I think it is right to agree. Rob says “hydrogeologists unite”, but in the end we want hydrogeologists, environmental regulators and environmentalists, Ofwat accountants and our political leaders all to unite, for without common agreement on the problem and the best solutions we’ll be on an adversarial merry-go-round for ever.

I will post comments from anyone who wishes to join the debate over Christmas.

Précis of Rob Soley’s webinar presentation, organised by the groundwater modellers’ forum of the geological society:

Rob’s words in blue.

(discussion/comments by CRW in red)

Rob emphasised that he is “standing on his own soapbox” to air concerns about proposed potentially enormous groundwater abstraction reductions in the national framework draft plans. The elephant in the room, he says, is vaguely greenwashed and represents water resources folly in the pursuit of questionable ecological benefits.

‘Sustainable’, Rob argues, once encompassed ‘environment + people + carbon + money’. Now, river-flow standards are being pursued regardless of benefit or cost and we are on the verge of giving up a huge amount of groundwater storage. The altar of naturalness has made smart management a ‘dirty’ concept.

(Worth remembering that this pursuit of river-flow standards is only a potential pursuit at the moment: right now many chalk streams around London and Cambridge and into Kent are very heavily abstracted – abstraction totals of between 30% to 60% of recharge from rainfall – and will continue to be for years to come, no matter what. 

I agree that ‘smart management’ should not be sacrificed on the ‘altar of naturalness’)

In the early noughties the EA developed an abstraction-pressure screening process, consisting of a natural-flow duration curve, below which hung an impacted but idealised flow threshold (the Environmental Flow Indicator or EFI): in the places where the actual flows dipped below the idealised impacted flows a sustainability-assessment screening process was conducted which considered the environment + people + carbon + money. Over the past 20 years that definition of sustainable has changed, until now it considers only the environment, with the target an imperative. 

(This isn’t quite true. Rather, over time the weighting and even definition of these values has changed and therefore the balance within the definition of sustainable has changed. For example, what people are prepared to pay for has changed as their feelings about the importance of the natural world have changed: the definition still includes people, what they care about as well as the cost of water from their taps. The carbon cost may change too and certainly will when humankind cracks nuclear fusion, at which point the carbon costs of groundwater abstraction will become the absence of wetlands, and the definition of sustainable will once again have to shift to reflect this.)

And the target has been tightened.

The risk is that many of the reductions will not deliver the anticipated benefits. The process of national re-plumbing is going to be hugely expensive. With climate change our lows flows are likely to fall and so we need to consider how to make our environments more resilient.

Previously the map of groundwater (GW) abstraction impacts included the good (green), bad (amber) and ugly (red). The desire now is to turn the whole map green, by reducing the current national total groundwater abstraction total from 6,300 Ml/d to 3,500 Ml/d. We will attempt this by moving from a system of local water for local people and building more pump transfers, desalination plants, surface reservoirs: and all just to stand still (ie. reduce g’water abstraction) and before we address sustainability of water supplies.

(The environmental impact of “local water for local people” varies greatly depending on population density versus rainfall. For the chalk streams around London that ratio and the ‘local for local’ principle condemns the rivers to chronic and significant flow depletion. Local systems are gravity-dependent and thus subsidised by the environment while that environment gets bypassed in the supply-discharge loop. There is always a cost: it’s just a matter of the degree to which nature picks up the bill versus what we are prepared to pay in order to retain/restore nature.)

Switching off GW abstractions on this scale will sterilise our access to a vital resource while the environment will continue to be stressed by droughts and climate change. 

(Worth pointing out here that the Chalk Streams First concept is not proposing to “sterilise access to groundwater”: as a concept CSF still sees the aquifer as a water-resource reservoir. But CSF argues for using the stream as the means of delivery, rather than bypassing it: hence the name Chalk Streams First. Note that later in his talk Rob tries to show the difference between groundwater abstractions that subtract directly (both temporally and spatially) from the stream flows and those that subtract from distant storage with a delayed impact.)

We should carefully prioritise GW-abstraction reductions, alongside better management and habitat creation, yielding quicker, cheaper, and better ecological outcomes. .

(Conditionally agree: quicker, cheaper, better than ? … abstraction reductions per se, or poorly planned abstraction reductions? It shouldn’t be ‘either, or’.)

How did we get to these levels of proposed reductions?

The EA’s first national screening process was the CAMS ledger, incorporating 1200 assessment points of flows often at flow gauging station to improve confidence, and a screening process of natural versus recent actual and fully licensed flows.

The water framework directive (WFD) added 8,300 assessment points, with concomitant upstream migration of assessment. The assessment tool became the Water Resources GIS (WRGIS) linked to CAMS ledger spreadsheets. The screening process fed into WINEP.

WRGIS + the “FIXIT” tool fed into the national framework, looking at places where flows are below the indicator and calculating the reduction in abstraction needed to meet the target. It worked iteratively down the catchment, waterbody by waterbody. This developed the numbers the EA sent to water companies. Initial estimates of the groundwater abstraction  reductions required (to meet the ‘Business as Usual’ environmental flow standards without any water body exclusions and before accounting for climate change) indicated a total reduction of 2713 Ml/d from 6228 Ml/d (recent actual) (and a reduction of 4682 Ml/d from 11300 Ml/d fully licensed).

The chalk stream strategy has catalysed the further upstream migration of assessment: now quite seriously on the table is the need to protect chalk springs “where they are”. Protecting perennial springheads where the Q99 is close to zero: 5% of no flow is no abstraction. The conclusion of this is that “this is not an aquifer for people anymore”.

(The chalk strategy made the point that flows at the waterbody boundary aren’t necessarily representative of flows higher up the catchment, especially when the assessment point is below a significant discharge. There are plenty of examples, but the Ivel, for one, is assessed downstream of the Pix tributary and a sewer discharge: it is assessed as “supports good” for flow when the upper, chalk stream reach is very frequently dry. Concluding that arguments for the river’s restoration amount to “this is not an aquifer for people” arguably does not reflect how much people have come to care about their local chalk streams. In fact, the chalk strategy has proposed that we need strategic abstraction realignment in the places where abstraction is currently 20, 30, 40 or even 50+%* of recharge. This does not have to mean a 100% net loss to supply at all, but rather an evolution away from old-school infrastructure towards intelligent, conjunctive systems that allow the streams to flow whilst also utilising the water for public supply. This is perfectly possible, but it will cost some money.

*Interestingly, Rob agrees that A%R is perhaps a better way to assess abstraction impact and reduction prioritisation, because driving flow targets higher and higher up the catchment leads to increasingly stringent and unrealistic abstraction reductions: this is because chalk streams are naturally ephemeral in their upper reaches and trying to achieve no more than a 10% reduction from a tiny amount of flow or even no flow effectively amounts to zero abstraction: the meaning of his penultimate line in the preceding blue paragraph.)

Also the approach to the environmental flow regulation has tightened. We’ve gone from an assessment where sustainable included considering things more broadly to one where you just have to meet the flow standard. There is a mechanism of local override but it is usually impossible to make that stick because the data isn’t there and it is impossible to move away from the precautionary standard. 

(This is rather as if the precautionary principle has triumphed and we are in world of fully naturalised flows. It hasn’t and we aren’t.)

The national framework has tightened this yet further, so that now there is a notion that all chalk streams should be ASB3, all salmon streams should be ASB3. There hasn’t been a great deal of evidence presented to argue why that should be. There’s just the notion that these things are crown jewels, “without considering whether those standards are what the ecology really needs”.   (without clear impact evidence).

(Abstraction sensitivity bands (ASBs), as the chalk stream strategy shows, evolved out of flow targets which were originally determined by river type and expected macrophyte, invertebrate and fish communities (and their dependence on flow for health). ASBs , therefore, should be determined by a river’s type / potential, not current condition. But ASB designations have become muddled in places by a somewhat automated process that managed, for example, to designate streams like the upper River Nar as ASB1 (least sensitive). Every single chalk stream in England once contained salmon and nearly all still contain trout and often sea trout (the presence of salmonids, especially migratory salmonids should mean automatic ASB3 designation). Chalk streams’ natural macrophyte and invertebrate communities are also rheophilic (flow loving) and if the actual communities are now different (ie dominance of chironomid lava and cyprinids) this will ALWAYS be the result of anthropogenic modifications, usually a combination of abstraction, impoundments, canalisation and pollution. Therefore, there is a very good case for arguing that all chalk streams should be ASB3 because, the ecology of a chalk stream depends on flow. However, in the chalk strategy we have also conceded that ASB3 might not be appropriate (ie it would signal unjustifiably large abstraction reductions) in the lower reaches of big systems, which would benefit from upstream flow recovery anyway, or systems that are so heavily modified as to make restoration of ASB3 flows rather pointless, because the bigger constraints are immovable navigation locks or such-like.) 

All of that is true at the moment however bonkers the cost.

(The total reductions mooted at the moment do appear to have been generated by a computerised exercise (probably unavoidable as a first pass) without the important next step of prioritising and strategising. This next step is really important.)

And at this stage of the WRMP all the water companies are saying “okay, we’ll put it into the plans if that is what you want” and that’s going to go round the hoop until it gets to Ofwat, who may well tell us that we can’t afford it.

We need to get back to a more holistic, less siloed approach (flow + m’ment + habitat + water quality) to deliver real local biodiversity benefits more quickly and affordably “without trashing our resilient GW supplies on a massive scale” “with some understanding nationally of how much money we want to spend on this problem”. 

In parallel with this story there has been a development of regional groundwater and river-flow models: you can use these models to look locally at each stream cell and the river waterbody outflow points to check the compliance with these standards. 

There are lots of examples where both modelling and experience show ‘disappointing’ returns at low flows relative to the amount of abstraction reduction.

(For various complex reasons a unit of abstraction (or abstraction reduction) tends to have a greater impact on high flows than low: ie. if you reduce abstraction by a given unit (say 1 Ml/d) the impact on flows will be well over 100% at high flows and as little as 30% to 20% at low flows*.

*The impact on flows is expressed as an impact at the time, but this is not the full picture, because the impact is not a direct one but takes place via the impact on groundwater levels. A unit of water abstracted at low flow periods may have a smaller impact on the force which drives flow (because groundwater levels are low), but it nevertheless removes that unit from the total flow discharged from the valley: in fact it creates a debt to future flow, by delaying the rise of groundwater levels during recharge. This is why the oft repeated idea that abstraction has no impact on flows once groundwater levels have fallen below the river bed – and the river has dried – is misleading. It has an impact on future flows just like accumulated debt has an impact on future spending power.)

There is a good example on the south coast near Chichester of a chalk source on the River Wallington, between the River Meon and Bedhampton springs. Outflow points from the aquifer are at different elevations. The Wallington is relatively higher than either the Meon which gets baseflow most of the year round where it flows off the chalk and the Bedhampton springs at the base of the chalk. The impacts of the abstraction show that most of the impacts on the Wallington occur at high flows when GWLs are high and the chalk is spilling. On the Meon the impacts are constant through the year and at Bedhampton the impacts at low flows are actually higher than at high flows (when the aquifer overflow is pouring out of the Wallington). All because of the different elevations of the drainage points from the aquifer. The variable pattern of impact is true in other settings, for a combination of additional reasons to do with the non-linear behaviour of the aquifer, the variations of permeability with depth, winterbourne path-lengths changing as the aquifer fills or drains, the layering of the aquifer, evapotranspiration rates as groundwater comes close to the surface etc etc.

(The impact of abstraction is shared between three sources of discharge from the aquifer: the Wallington, the Meon and the Bedhampton springs: very simply you could see them as three vertical columns of holes with different uppermost elevations in the side of a bucket: the Wallington holes extend much higher up and as the water runs out of the bucket so the flow deserts these holes first, whereupon the impact of the abstraction becomes progressively more exerted upon the other two columns of holes. In this case, therefore, the impact of abstraction on the Meon and Bedhampton, but especially the latter is actually higher at low flows than high, because the impact is shared across three streams, one of which switches off almost completely.)

Therefore it is important to use these latest models to “wise-up” the EA tools such as the CAMS ledgers and the water resources GIS, because if not WINEP decisions are based on calculations that may not reflect reality.

Recently, and in response to the chalk strategy, the EA has proposed assessing flows at the perennial head of chalk streams, called Point X. The Fixit tool can be used to determine how much abstraction reduction would be needed to meet the flow targets at all the points of perennial outflow. 

Looking at the Cam Bedford Ouse model: to meet the WFD flow targets at all of the waterbody boundary assessment points abstraction would have to be reduced from the recent actual volume of 144 Ml/d down to 61 Ml/d. While to meet the same target at the springs (rather than the waterbody outfall) abstraction would have to come down to 18 Ml/d.

In the Quy sub-catchment currently 14 Ml/d of g’water abstraction leaves a non-compliance deficit of 7 Ml/d at the outfall. Plug in the reduction suggested for meeting the outflow compliance and there is still non-compliance in the headwaters. Plug in ASB3 numbers and this reduces, but not completely. Effectively you have to turn off abstraction to remove non-compliance at the spring-heads. This then creates a 5 Ml/d surplus (ref the target flows) at the outfall. 

(Worth noting that the generic CSF lumped parameter figures more or less match the sophisticated modelling figures in this case: reduce the abstraction to the point where flows re-naturalise and 12 out of 14 Ml/d manifest as surface flows at the outfall of the catchment. The Quy is on the Bedford Ouse system and is linked, therefore, to Grafham reservoir and in time to the proposed Fenland reservoir. In theory, therefore, we could restore flows to the Quy as in the CSF model, with a net average loss to supply of only 14%, albeit there would be additional costs involved in treatment and pumping and infrastructure. The proposal is not, therefore, to cease groundwater abstraction and source 100% of the reduction from completely different sources, but rather greatly reduce groundwater abstraction, find the 20% net loss through methods like efficiency improvements and then re-plumb in order to capture and use the recovered flow lower down the system. It is not accurate to represent the chalk strategy or CSF proposals as completely hands-off aquifers.)

Work by APEM for Severn Trent assessed the health of water bodies across Midlands against degrees of variance from natural flow. Pooled evidence suggests that at Q70 most sites with impacts of less than 50% are at good or better, (against EFI allowable reductions of 15% to 24%). This suggests we could adopt a less precautionary approach.

(I’m not convinced this case provides a useful application to chalk streams: were the assessed rivers in the Midlands salmonid streams with rheophilic ecologies? Rob’s main point though was that pooled hydro-ecological modelling should be carried out for chalk streams too, in order to see what the evidence suggests across the range.) 

The CSF model is a very simple lumped model. But “it fits really well”. Even with a simple non-linear representation of the head driving flow into a chalk stream, you get an indication of lower flow recovery at low flows compared to high flows. CSF is a good example of a modelling tool that is a lot cheaper and quicker to run but it doesn’t incorporate an understanding of the location of individual abstractions and how that influences their different impacts on river flows, which is why we can’t rely on it for making some of the really big decisions.

(Agreed: CSF is not designed as a decision-making tool at a micro-scale. It is partly designed to bridge the knowledge gap between hydrogeologists and the layman, in order to democratise the discussion. It is also designed to provide quick and simple assessments of abstraction impact. The fact that it fits really well again and again must also say something!)

An example of where the CSF model would not yield the requisite level of detail and where the impacts of abstraction reduction may not be justified:

Upper Itchen, “Source A”: on the syncline between the Wey and Candover, a long way from the perennial spring heads. Where and when does this abstraction impact flows in the Rivers Wey, Candover and Dever? A steady-state abstraction impacts these three rivers with a similar pattern of variance as the Wallington Source: the biggest impact is on the Wey, almost 7Ml/d at high flow, down to 1Ml/d at low flows. The Dever impact on the other hand is much more steady 1 to 0.5 Ml/d. Added all together the impacts are 18 Ml/d at high flows and 3 Ml/d at low. In other words, at low flows “you might not notice it that much”.

(This is where Rob is trying to draw a distinction between chalk groundwater sources which subtract directly /almost immediately from stream flows and those that subtract from distant storage with a delayed impact. This upper Itchen source, like the World’s End source impacting the Meon, Wallington and Havant springs uses groundwater storage with, as Rob argues, minimised environmental impact. 

The reason: “this is a source that develops drawdown in the summer: that’s a good thing. It’s not mining. It’s taking water from storage rather than directly from river flows.” The process here is the same as why good groundwater augmentation schemes work … they provide immediate summer low flow gain in discharging to the streams (providing it doesn’t leak back in) because the impact of the abstraction is not instant – it is offset to the next recharge season.

Candover augmentation scheme also scheduled for decommission: in the past it has supplied up to 22 Ml/d for abstraction in droughts. It can also supply on a more frequent basis enough water to keep flows close to natural in the Candover. So, the aim of having flows close to natural can be achieved without turning off all these abstractions. But there is a mantra now that we have to restore everything “to natural” and that we can only achieve that via switching abstractions off.

(I agree with Rob that the concept of a natural aquifer is potentially a distraction from finding workable and good conjunctive solutions. Combined with downstream surface-water abstraction off-takes, the upper-catchment groundwater storage here (ie. aquifer) surely has the potential to deliver almost naturalised flow volumes via the stream: I don’t think we should rule out ideas like this. Augmentation has a bad reputation but we should question why, if it gives us a way to retain water supply resilience and ensure close-to-natural flows. We should try to arrange some open discussions between Rob, the CaBA chalk stream group, Chalk Streams First, and Natural England / Environment Agency on this topic.)

The upstream abstraction reductions of 11 Ml/d Source A 3 Ml/d Source B 26 Ml/d augmentation add up to 40 Ml/d. Plus another 40 Ml/d from downstream = 80 Ml/d of resilient drought supplies lost only to be replaced by effluent recycling / desalination / distant reservoirs and pumping: this is untried, costly (hundreds of £millions) and carbon heavy. The “environmental benefits uncertain”. Protected areas need active management to protect them … let’s not leave them entirely at the mercy of climate change without groundwater augmentation.

(As above: there are ways to reduce abstraction impacts without creating a 100% net loss to supply.)

Another example of where the cost of abstraction reduction may not be justified:

Avon: most of the Avon is within CSMG flow targets, except for the final 1km, where the flow deficit is -70 Ml/d, almost the entire supply for Bournemouth. To replace this will increase low-flow abstraction from the Stour, a river with less resilient base flows, via stream support, relocation of 30 Ml/d wastewater recycling, plus aquifer storage and recovery schemes, all at a cost of £300 million.

There is little evidence of ecological impact on this reach. None in terms of invertebrates. In terms of fish migration there is no clear correlation between fish migrating up the Avon versus flow or temperature, although there is clearly a spate flow response (Rob showed a chart of 2020 salmon runs into the Avon). In addition 2020 saw far greater returns than any of the previous years since 2006 through which time abstraction pressures have been constant.

(Salmon return numbers and timing depend on so many factors and the overarching control is undoubtedly conditions at sea, especially sea temperature impacted by global warming (unnatural) and the North Atlantic multi-decadal oscillation (natural). Our job is to ensure the natal streams produce as many salmon as possible: so the real question is whether a 70 Ml/d reduction in flows is likely to inhibit salmon from entering the system or reduce the salmon-producing potential of that system? At average flows in a base-flow supported system like the Avon, maybe not. In drought conditions, maybe yes).

Q: is the legal requirement to reach the SAC target worth 300 million? 

(I feel Rob has a point here, especially because the Stour is also a salmon river. There may be cheaper or better ways to overcome the real risk to returning salmon trapped in the estuary in drought conditions: for example, salmon are attracted to velocity and turbulence (as well as the scent of fresh rainfall) when running upstream and there must be ways to create both in the lower 1km?).

Ref the future we know flows are on a downward trend with climate-change impacts. Where will supplies come from if we abandon g’water?

What do g’water modellers need to do?

• need to make their models fit. CSF fits even if g’water modellers don’t believe the concepts*. But regional models which include the concepts don’t always fit very well. Need local refinements for credibility.

*(maybe the concepts fit too!?)

• have to engage in the model wising-up processes to improve the national WRGIS data

• need to use the models to give stakeholders engagement: make model easy to share and improve

• need to talk about ecological benefits versus cost and challenge the green myths which say that:

• vast GWABS reductions are good (unwise, costly, uncertain benefits). 

(Agree, we need to be strategic and judicious to avoid the risk of undermining the whole project.)

• GW augmentation a bad thing (actually supports river flow and abstraction). 

(Agree, we need to consider the role of using the stream to deliver water: this is not augmentation as such, but a different way to plumb water supplies. Even pure augmentation has its place.)

• we’ll easily use less water (a very uncertain outcome).

• we’ll easily reduce leakage (without digging up cities?).

(Agree, both demand and leak reduction offer uncertain, untested savings at this stage. We need schemes that provide certain relief to the highly stressed chalk streams and we need them soon!)

• wetlands will improve drought flows (may just increase evapotranspiration).

(Yes, but they are still ecologically desirable and they lock up carbon.)

• protected areas need to be left as “natural” (no such thing. active management is a good thing).

(Agree, we need to actively manage.)

• make the most of our aquifers for people and the environment. Embrace well located groundwater abstraction reductions. Encourage effective GW river support schemes.

(Agree.)

• work across organisations to deliver biodiversity benefits now.

(Wholly agree)

• reclaim a more holistic meaning of the word sustainable.

(Yes, but values change. Holistic must include those changes too.)

In summary, Rob is saying that we should be very wary about abandoning our climatically resilient (mostly chalk) groundwater supplies and investing many millions in an untried, untested, carbon-costly re-plumbing exercise, all in the name of uncertain ecological benefits. Instead, we should keep most of what we have in place, make reductions in a few locations where they will make a big difference to flows and ecology, and instead we should work on habitat improvements which will give us better outcomes for less money.

And I agree with some of that, certainly that we should carefully prioritise abstraction reductions so that they deliver tangible gains, something that will require transparency, knowledge-sharing and democratic discussion. But it is not a question of abandoning chalk aquifers so much as allowing chalk streams to become the means of delivery of water from the aquifer to the tap, meaning that restoring flows should amount to much smaller net reductions in public water-supply than the bare modelling headlines suggest. Habitat improvements can make a vast difference, but only once flows are back towards an acceptable level: in many chalk streams around London, Cambridgeshire and Kent where abstraction is over 20% and up to 50%+ of average recharge, flows are not acceptable. But all these deficits added together come to a manageable volume -400Ml/d) especially when it is possible to reclaim much of that water lower down the catchments.

The chalk strategy Implementation Plan: V1. 2022.

(Above: not so long ago this part of the River Glaven was locked in a tunnel: now look at it! There’s hope for all our chalk streams if we dare to make it happen)

I should have posted this on Friday but I was busy chairing the Chalk Headwaters Conference at Sparsholt and catching up with many old friends from Wessex chalk stream country. My presentation there was on the chalk strategy but also the chalk strategy implementation plan, which was published that day. Please take a look at the new plan HERE.

This plan has been many hours, weeks, months in the making; many phone calls, emails, meetings, consultations and negotiations. It’s not a once-and-for-all fix-all, but I do think it marks a step-change in our collective attempts to restore good ecology to our beleaguered chalk streams.

Not only do we have a consensus plan with consensus actions and timelines, but we have now garnered explicit support from all quarters – regulators, industry and NGOs, and the small-but-becoming-bigger-every-day army of chalk stream enthusiasts – for ideas like the flagship projects, the review of waterbody boundaries & abstraction sensitivity bands, the enhanced scenario for chalk streams in the national framework planning process, Chalk Streams First etc.

It’s great too, to have such supportive statements from the Minister, the Rt. Hon. Rebecca Pow MP, and from Defra and the Environment Agency. And from Ofwat too. These give us real gas in the tank when making the case for all the things we need to do to bring chalk streams back to health, whether that’s abstraction reduction or sewerage infrastructure investment or physical restoration of habitat.

Sadly, we are still not quite there when it comes to the greater and more explicit protected status we all asked for, along with the necessary investment driver. But I still have hope: the changes in government over the summer stalled progress, and it would be nice to think things might get back on track now Minister Pow is in post again. We all know what a difference enhanced status would make, by taking the brakes off investment along the lines established by making chalk stream high priority sites in the stormwater reduction plan.

This implementation plan will be revisited and revised every year, a commitment that I hope will help hold us all to task. So, over the next 12 months, let’s see how far we can get with actually making some of these ideas a reality. I hope, in 12 months time, to see tangible progress with the planning and construction of integrated wetlands, with the agreed level of environmental ambition for chalk streams in the national framework, with Chalk Streams First not only in the Chilterns but elsewhere, with the flagship projects and with the strategic and outcome driven planning of stormwater discharge reduction.

Onwards.

My five minutes in Westminster: the WRSE parliamentary launch

I was very pleased (with thanks to Trevor Bishop, WRSE director) to be given five minutes this morning to talk about Chalk Streams First as part of the parliamentary launch of the WRSE draft regional plan.

Trevor opened the speaking with an encouraging summary of how this plan could be a real game changer in terms of making environment stewardship integral to a more resilient and sustainable water resource infrastructure. As I say below, this is our best chance ever, to build a better system that is fairer to the natural world. And to restore our over-abstracted chalk streams!

It was great to see Sir Charles Walker MP, The Rt Hon Phillip Dunne and Sir Oliver Heald, MP – all stalwart chalk stream supporters over many years. Many thanks to Sir Geoffrey Clifton-Brown MP for hosting, on behalf of WRSE.

You can read the plan and give feedback HERE. Please do take the time to take a look and especially to give feedback ref the importance of abstraction reduction for chalk streams.

There will be a webinar on the 22nd Nov at 1330 to 1500. Register to attend HERE

My five minutes worth were as follows:

“As we plan for the future it’s important to remember the past: the miracle of running water and flushing loos in every home, on the one hand, and on the other the true cost that miracle imposed on the natural world.

In a cupboard in the High Wycombe public library there is a Sanitary Inspector’s report from the mid-19th C on the conditions in which the chair-factory workers of the town were living. Their water came from the stream, over which hung latrines, or from wells in the floodplain, the wells sometimes only a few yards from garden-shed loos, also holes in the ground, shared by forty or fifty people. 

Most people were ill more or less all the time: they called it low fever, and thought it came from the awful smell, but it was cholera and it came from the dirty water. The report recommended piped water and a sewage system, but the councillors were concerned about the cost and it took decades to materialise. In fact, the slums themselves lasted until the 1950s when they were finally cleared and the occupants rehoused in airy, council houses on the hills above the town. 

In those post-war years the resource of abundant, clean water in the chalk hills under those lofty new houses was nothing short of a miracle. It enabled the re-housing of Londoners bombed out by the Blitz into smart new towns and garden-cities in the Home Counties.

It enabled – and it subsidised – an amazing growth in prosperity and health. Hardly surprising that groundwater abstraction from the chalk aquifer grew almost exponentially in those post-War decades, climbing to a peak in the mid-1980s where in many of the chalk valleys around London over half the rain that fell from the sky to fill the aquifers was taken for public water supply. In dry years an average of half the rain, became all of the rain. 

And although the water was free to us, there was a bill: the natural world picked it up. Those lovely chalk streams – a freshwater marvel almost unique to southern and eastern England – ran dry.

For forty years we have wrestled with how to resolve this dilemma: the convenience and low cost of water from the chalk aquifers and versus the ecological impact of drying and dry chalk streams. Round and round we go, sometimes denying the problem, endlessly measuring the problem, but never quite fixing the problem.

Now, through this regional planning process we have the best chance we’ve ever had, and may ever have, of achieving a better balance between the needs of society and those of the natural world.

The potential component of the plan that I’m especially passionate about consists of realigning the way we take water by creating the sort of system we should have built in the first place, if only we’d known.

Instead of taking water from the ground in the headwaters of these lovely chalk streams, we should take it much further downstream, after it has flowed down the rivers and nature has had first use: hence the name of our proposal, Chalk Streams First.

Chalk Streams First is supported by all the major environmental charities – the Rivers Trust, Wild Trout Trust, Angling Trust, the Wildlife Trusts, Wild Fish and WWF – as well as the local environmental groups in the Chilterns and Hertfordshire chalk hills, where the opportunity is ripe for the taking.

Chalk Streams First is a proposal that greatly reduces abstraction pressure without losing the water to public supply: much of the water left in the ground becomes surface flow which can be taken further down the river, placed into storage reservoirs and then used to supply all the places formerly supplied by the groundwater abstraction. 

There are potential variations on the theme too: inter-regional water transfers like the Grand Union Canal, or Severn to Thames, could bring water into the upstream catchments, with the recovered flow going on to London. 

Groundwater abstraction in the headwaters can be replaced by groundwater abstraction further downstream where there would be less ecological impact. 

In places where there is no reservoir, or to get us through 18-month droughts like the one we have just experienced, we could use emergency groundwater schemes and use the chalk streams to deliver the abstracted water to public supply off-takes.

The point is, we can do it: we can have flowing chalk streams and resilient public water supplies.  It just requires political will and engineering ingenuity. And while it needn’t cost the Earth, it might just save our piece of it. Please support Chalk Streams First and help us to make it happen … soon.

Thank you.”

Sir Charles Walker, Trevor Bishop and yours truly at the parliamentary launch of WRSE’s draft regional plan.

South-eastern chalk streams

The South East Rivers Trust (SERT) is doing some work to ground-truth chalk streams in the south east (pictured above is the Nail Bourne, a tributary of the Little Stour). They’ve created a map of the recorded high and low-certainty SE chalk streams and are asking people to feedback on this: https://www.southeastriverstrust.org/help-us-identify-all-south-east-chalk-streams/

This links closely with work I’ve recently been doing with NE to identify all the country’s chalk streams. Even as we finished we were aware that even though we had tried our best to find and identify everything, there were most likely other valuable sites we had missed, especially amongst the more complex network of scarp-face, spring-line streams.

I have already posted HERE about making contributions / updates to the Natural England map. But with SERT collating efforts in their patch, you might also want to take a look at their portal.

A brilliant document

I’ve been doing a few presentations this autumn, including at the 25th anniversary of the Chilterns Chalk Stream Project: a fascinating day in St Alban’s with a walk beside the River Ver through Verulamium Park.

To mark the day the Chilterns AONB produced a booklet called Celebrating 25 Years of the Chilterns Chalk Stream Project. There were a few copies in the room and I made sure to keep mine. It includes a fascinating, stream by stream analysis of pressures including some revealing water quality charts which show so clearly how various pressures very between different parts of a given stream and between streams: the impact of the canal on phosphorous levels in the Bulbourne, for example, is clear as day. But it’s more than a techie analysis: it’s very approachable and it also evokes so well how important chalk streams are to this special part of England.

When I mentioned to Kate Heppell how good I thought the book was, she said they had only printed a few copies. Which is great shame. However, it is now available online as a PDF and if I were you I’d download a copy pronto as it is a fascinating read and a fascinating history of the Chilterns Chalk Stream project and all the good work it does.

CELEBRATING 25 YEARS OF THE CHILTERNS CHALK STREAM PROJECT

A question in parliament from a supporter of chalk streams

Photo © Matt Writtle: Rebecca Pow MP by the River Mimram at the launch of the CaBA Chalk stream restoration strategy in October 2021

I’m delighted that on the 12th October 2022 the Rt Hon Rebecca Pow MP managed to raise the issue of ecological protection in parliament – citing chalk streams – making the point that a healthy ecology and a healthy economy are not mutually exclusive, rather they are symbiotic:

“I fully support this Government’s growth agenda, but would the Prime Minister agree that it can be achieved while also protecting and restoring our precious nature and ecosystems and working with our farmers, so that we meet our legally binding target to restore nature by 2030? I know she understands that; she has precious chalk streams in her own constituency. Will she agree that, if we get this right, there will be more jobs, skills and opportunities, because every nation in the world depends on its natural environment?”

I’m delighted also that the Prime Minister’s response was emphatic and in agreement:

“My hon. Friend did a fantastic job promoting the natural environment when she was at the Department for Environment, Food and Rural Affairs. We are going to deliver economic growth in an environmentally friendly way. This is about improving the processes and delivering better outcomes for the environment while making sure we have a growing economy as well. Those two things go hand in hand.”

The Chalk Streams First idea, for example, is a wonderful opportunity to place an iconic ecological project at the heart of a national grid for water. Ecology and the economy together.

Farming in chalk landscapes

One can’t help but be concerned at the news this morning that the new-look government is planning a review of ELMS, the UK farm subsidy scheme which will replace the EU’s CAP, “given the pressures on farmers, and the government’s aims of boosting food security and economic growth”.

Although a lot of good work has gone into ELMs nothing is beyond review, so this may not be the de facto existential disaster many conservationists are predicting. What is frustrating however, is the endless framing of this conversation about farming and nature as a binary choice between economic growth and ecological protection.

Both sides – if I can put it that way – are to blame for this. Conservationists too often make excellent the enemy of the good. Threatened by what they see as impractical, idealistic environmentalism, farmers can be reactionary and unwilling to take on new (in fact, old) and practical ideas about land husbandry.

It doesn’t have to be one or the other!

It is in fact perfectly possible to farm in a way that leaves space for nature, or to put it the other way round, it is perfectly possible to make space for nature whilst farming profitably and providing an invaluable service to society. (Jake Fiennes’ new book Land Healer is all about this pragmatic, conservation-minded farming: exactly why I was very pleased when the NFU asked Jake to represent farming on the CaBA Chalk stream restoration strategy panel: in fact his book wasn’t out when we developed the strategy, but I had met Jake and our ideas clicked.)

That’s also why we’ve been trying to develop / evolve, from the CaBA chalk stream group, a simple set of recommended rules for farming in chalk landscapes which we will put to Defra in mid November when we launch the implementation plan for the chalk strategy. With a review on the horizon, this could be timely.

Background

The CaBA chalk stream restoration strategy, published in October 2021, included a number of recommendations for simple rules for farming in chalk catchments.

The idea was to propose to the teams developing ELMs a small number of rules and incentives that would be:

• easy to follow

• effective

• practicable

• and would not adversely affecting the profitability of the farm business 

The reasoning was that a good combination of the above would generate much higher take up and could be easily be regulated. I live in the countryside. I know many farmers. I know many chalk streams and I have practical experience of the impacts farming has on those chalk streams. I am sure that most farmers would be more than amenable to simple, practical ideas that help chalk stream to flourish, so long as these ideas are grounded in the practicalities of farming and of trying to make a living against the headwind of all the bureaucracy and diverse pressures farmers are under.

As chair of CaBA chalk group I was recently invited to sit on Defra EEG+ working group meetings and the Water theme for SFI and ELM. So, I decided to try and improve the first set of ideas via a series of meetings but with farmers and land managers driving the discussion. My plan was to take these ideas to the Defra meetings, backed with the expertise of the farming community.

Thus far we have had one meeting with a number of farmers in Norfolk and I now have two more booked: in Wessex on the 12th October and in the Chilterns on the 26th October (organised with the help of the Wessex Rivers Trust and Chilterns AONB respectively). I’d also be very keen to hear from other farmers and would be happy, if time permits, to hold an online meeting as part of this process. Get in touch if you’re interested. Although I can’t say how influential the ideas will be, the more that farmers contribute to and shape them the better.

In chalk catchments even a small area of land –  if not well managed – can provide a very large problem via run-off pathways such as the road network: this picture is from the Wissey valley in May 2021 (there is a much broader buffer on this field now!).

Focussing on sediment run-off and chalk streams.

The impact of farming on water quality in streams is a potentially complex area but I want to focus on sediment in chalk streams because sedimentation has a very big impact that could be largely addressed with some very simple interventions.

Chalk streams in their natural state are ‘gin clear’ with very little sediment, clean river gravels and low nutrient levels: all of which is important for the ecological health and abundance of the species of plants, invertebrates and fish typical of chalk streams.

Our modern landscape, however, and the way it is farmed and developed, generates a lot of sediment run-off. And chalk streams being such gentle rivers have very limited flushing capacity. Many of them are modified by weirs and mills and denuded by abstraction which only makes all of this worse. In short, sediment gets into the river and it can’t get out, causing a significant negative impact on the ecology, by swamping out and homogenising habitat, filling the spaces in the gravel bed, or cloaking the bed of the river in particulate matter to which are attached phosphorus and all sorts of other toxic chemicals.

A 2005 English Nature Geomorphological Appraisal of the River Nar included a really good study of the ways sediment runs from farmland into a chalk stream. The report showed that fine sediment comes from:

• Arable fields – especially when they are recently ploughed.

• Pig units – there were increasing numbers in the valley, at the time (there are still many) some on steep land, close to the river.

• Road-side verges – especially when they are crushed each winter by farm vehicles too large for the roads they are driven down: this is a worsening problem.

• Dirt tracks – especially where these join up with the road network or run directly to the river.

• Aggregate works – from the exposed landscape around the works and from the road network servicing the works.

And that sediment enters the river via:

• Road crossings – where road drains discharge into the river.

• Footpaths, tracks and fords – where they cross the river.

• Intersections – of the dry valley network with the main river.

• Drains and ditches.

• IDB pumping stations and drains.

• Tributaries.

The important thing is this: in a chalk landscape points of sediment ingress are quite localised, but the area of origin can be broad. This is the case on most chalk streams, though the mixed geology chalk streams do get more surface run-off and chalk streams with livestock which graze to the river’s edge will also acquire sediment from damaged river banks. Urbanised chalk streams will also receive more diffuse surface run-off.

CaBA CSRG recommendations for farming rules in chalk catchments – DRAFT

Based on the above we have developed a set of simple rules / recommendations that could make a massive difference and which wouldn’t have to negatively impact the farming business. Sure, they’re are bit more bother than no bother at all, but there’s no real reason why these ideas couldn’t be adopted.

It’s also worth saying that there is an enthusiasm amongst the farmers I have spoken to for a level playing field: there is real concern and frustration expressed by farmers who go to extra effort to do the right thing only to find a neighbour not bothering. Therefore the idea of some very basic but compulsory rules appears to be well supported.

These ideas, as said, will be refined over two further meetings before being submitted by CaBA CSRG to Defra.

Basic rules

Compulsory basic standards for all farms in chalk catchments (could be trialled in the first instance via the CaBA CSRG flagship catchment restoration projects?)

• A farm-based site-specific soil and run-off audit and risk map, focussing on topography, gateways, and pathways from field to stream

• Compulsory buffer strips at high-risk leakage points (lateral width based on scale of risk according to the audit) designed to minimise escape of sediment on to pathways that lead to a chalk stream

SFI

As above plus …

• potentially higher impact farming such as outdoor pigs, carrots, parsnips, beet, maize, asparagus and potatoes: a 10-metre buffer around the full the perimeter of the field, but wider (up to 25 meters, say) at high-risk egress points (based on scale of risk according to the audit, while the areas of greater width can by offset by a commensurate area reduction along the low-risk boundaries)

• cover crops on maize fields (especially on sloped land)

• for outdoor pig units, a grass ley should be established before pigs are turned onto the land. Pig units should also not be sited on sloped fields or where the topography might increase the risk of run-off

• for other arable crops a 5-metre buffer where cultivated land runs alongside any ditch which leads to a stream, widening to 10-meters where cultivated land runs alongside any chalk stream itself (note that buffer strips preclude fertilisers, manures, pesticides, livestock)

• noting that later versions of SFI will include capital grants, recommend capital support for the relocation of gateways and crop pads from the high-risk locations as identified in the audit to lower risk sites

• adapt plough or cultivation patterns to minimise run-off in the infield high-risk areas as identified in the audit

• cover crops over all infield high-risk areas (based on levels of risk not just % of coverage)

• permitted crop-lifting and muck spreading periods set by a red / green traffic-light system based on localised 5-day weather forecasts? This system is used in Canada.

Local and Landscape Nature Recovery

Ideas to be developed could include: 

Infield

• cover crops 75 – 100%

• zero or minimal till 75 – 100%

• infield grass buffer strips running perpendicular to slope

• green swales runnings through field dips

• restoration of hedges, especially those running perpendicular to slope

• restoration of woodland

• restoration of ponds

Riparian and in-river for higher level offers

• restoration of lateral connectivity between the chalk stream and floodplain designed to allow riparian & floodplain inundation above Q10 flows (for example): this should be achieved by restoring natural river bed to floodplain ratios (ie by infilling dredged stream beds) and NOT by impounding the stream

• restoration or recreation of lost or relic meanders patterns 

• restoration of spring-line calcareous fens and flushes including infilling or blocking historic drainage and ditching networks

• restoration of wet woodland and riparian meadow by stepping back farming – except extensive grazing by suitable livestock – from the edge of stream

Note: throughout the discussion the group returned again and again to the need for chalk stream farming advisors to work with farmers on everything from the run-off risk mapping to the development of restoration ideas / opportunities. This is something that could be rolled out via the CaBA flagship restoration projects via the river trust network?

Incentivising hard to reach growers to support Local and Landscape Nature Recovery:

It was recognised that for proposals to have greatest impact they must be widely taken up across catchments. Collaboration was a common theme during the meeting, and farm clusters were identified as a potential mechanism to drive collaboration and engagement. A suggestion was put forward that payments for carrying out the proposed actions could attract a premium if they were obtained via a cluster group or similar (or standalone) initiative. However, this might not be feasible in areas where no cluster groups exist, putting some farmers at a disadvantage. It could also present new problems / cost / administrative burden?

A national grid for water resources AND saving chalk streams – let’s deliver that!

Our new Prime Minister mentioned chalk streams at a hustings in Cheltenham earlier in the summer and in yesterday’s Daily Telegraph she cited a problematic lack of investment (which she aims to change) in large infrastructure projects such as reservoirs.

All this is good news, suggesting the new look government will take seriously the protection of our precious chalk streams and not make the mistake – as has often been made in the past – of regarding economic growth and ecological protection as mutually exclusive. Chalk streams have been waiting a long time for the protection and investment which is due if we are not to continue as dreadful hypocrites, unable to look after the natural wonders on our doorsteps.

Yes indeed, we need reservoirs: in the Fens and Lincolnshire, in Kent, Hampshire and the Thames basin, reservoirs would facilitate schemes which could protect public supply and ease the burden of over-abstraction – and this year must surely have shown what a burden it is. But it is worth remembering how long it takes to navigate the inevitable public enquiries that surround reservoir schemes, let alone build them. If we rely on reservoirs alone, we will be waiting a while. I photographed the bone-dry River Beane (above) in 2007, 2017 and now again in 2022 and I’m not sure how many more times I want to do that.

To deliver an effective, simple scheme guaranteed to build resilience of supply and to facilitate the ecological restoration of our precious chalk streams, our new Prime Minister, the new-look government and the new environment minister should (as well as lighting the touch paper on longer-term planning) urgently catalyse a more timely suite of schemes along the lines of a national grid for water resources. Below is a short paper which I hope may have found its way to a desk at Defra. If not, I post it here, just in case …

A national grid for water resources.

The restoration of chalk streams around London should be the ecological flagship at the heart of a more fundamental reform of water resource infrastructure in England and Wales and the creation of a ‘national grid’ for water supply which imposes inter-regional transfers onto our currently siloed and fragile supply network.

The south east of England has a high (and growing) population and a comparative shortage of water, especially in drought years. 

The south east is currently dependent on reservoirs filled from the River Thames and groundwater abstraction from storage in natural aquifers. 

However, the Thames reservoirs cannot be reliably refilled in dry winters. This runs counter to the mistaken popular perception that we only need to build more storage: there is already more storage than supply in the south-east during the problematic 18-month droughts, which include dry winters.

Groundwater aquifers, on the other hand, are already over-developed and the degree to which they are exploited causes significant ecological damage, particularly to chalk-streams, many of which are currently dry or very low (August 2022).

Fundamentally, the South East of England needs “new water” because not enough falls from the sky relative to the number of people and the needs of an already damaged environment.

By far the quickest way to achieve this is through inter-regional transfers from wetter and less populated parts of the country. For example, average annual rainfall per capita in the south-east of England is a fifth of that in Wales (assuming SE England = 19096 km2 / 800mm ave rainfall / 9.2 million people and Wales = 20779km2 / 1500mm ave rainfall / 3.2 million people).

The potential of inter-regional transfers (to supply water to the south east from Lake Bala in Wales) was first proposed by a Hertfordshire miller, John Evans, in the 1870s. It resurfaces as an idea every time there is a severe drought and then gets forgotten again till the next time.

More recently, however, the need for inter-regional transfers was firmly identified in the 2016 Water UK report: ’Water Resources Long-term Planning Framework’.

The role of inter-regional transfers is now a key component of the emerging National Framework for water resources and specifically WRSE’s draft plan which proposes that inter-regional transfers are used to move water from the wetter west to the dryer south east, including options such as Severn to Thames Transfer, repurposing the Grand Union Canal to transfer recycled water from the River Trent to the South East as well as potential options for transfers from the west country. 

However, the National Framework timetable proposes that water demand management (water efficiency and drought measures) and leakage reduction will close the largest part of the supply demand imbalance through to 2050. 

Shrinking demand through water efficiency is a vital measure, but offers uncertain results, while the already existing shortage of naturally available water in the Thames valley (as evidenced by the current drought) will become more pronounced if demand grows or if demand management proves a hard nut to crack.

Delaying the use of inter-regional transfers until after 2050 also delays the restoration of flows to the chalk streams which depend on over-exploited aquifers (and thus risks more and more headlines about dry rivers).

Severn to Thames Transfer

A transfer of water from the River Severn to the River Thames could yield in the order of 100 Ml/d, (in itself enough to restore close-to-natural flows to all the Chilterns and Hertfordshire chalk streams) requires zero inter-company trading and is deliverable in the short term.

With support from Vyrnwy, the Severn-Thames transfer could provide up to 500 Ml/d of yield for Thames Water and other water companies in the South East. 

The draft WRSE regional plan indicates that the Severn to Thames transfer could potentially be implemented by 2033.

Minworth and the Grand Union Canal

A complementary option that amounts to the same principle of moving water from Wales to the south east involves the recycling of highly-treated effluent from Birmingham’s Minworth water recycling centre, transferred to the WRSE region via the Grand Union Canal. 

The Minworth GUC transfer has a potential yield of at least 100 Ml/d (potentially higher given the dry flow from Minworth is 420 Ml/d) via the Ground Union Canal.

The draft WRSE regional plan indicates that the Minworth GUC transfer could potentially be implemented by 2035.

Both of these options bring new water into the south east region and would allow ALL of the abstraction reductions needed to restore naturalised flow to the iconic chalk streams of the Chilterns and Hertfordshire.

Chalk Streams First

These abstraction reductions in themselves also – counter intuitively – offer water resources options because they do not involve a total net loss to supply. A drastic reduction of groundwater abstraction in the chalk hills would allow groundwater levels and thus river flows to recover: in the Chalk Stream First scheme the aquifer remains a “reservoir of water” while the means of delivery becomes the chalk stream itself, with water taken for lower down the system after the natural eco-system has benefitted. Hence chalk streams first

The flow recovery brought about by abstraction reduction is another strategic resource option amounting to approx 80% of the abstraction reduction averaged across the full year (flow recovery is lower in summer than winter, ranging between 30% and over 100%), using the London reservoirs as storage, and the Supply 2040 pipe network to return water to those places formerly supplied by groundwater abstraction.

Chalk Streams First +

Moreover if the problematic groundwater abstractions in the chalk tributaries are wholly or partly replaced with groundwater abstractions in the lower valley (an idea added to the proposal by Affinity Water) where they will have a much lower ecological impact, then there is no net loss to supply and ALL of the surface water flow recovery becomes available as “new water” in the same category as the STT and GUC water. This could yield up to 80 Ml/d averaged through the year. 

Chalk Streams First offers the opportunity to put a flagship ecological restoration of England’s iconic chalk streams at the heart of the development of a national grid for water, and inter-regional water supply infrastructure which would, for the first time in history, move water from the wetter west and Wales, to the overstretched and dry London and the south east.

Let’s deliver that!