As the UK’s drought continues and the Maize for winter feed withers in the fields we need an alterative. Our farmers are already feeding winter food to their livestock. There is an option and it is called Duckweed. That green stuff floating in our ditches and rhynes. It may well provide the alterative to farmers having to cull their livestock or buy in expensive food, if they can find it?
Even if the rain comes now, August 2026, the loss of crops will still create feed shortage through the winter. With wetter warmer winters Duckweed may be the best hope to create the feed the farmers need.
Duckweed production provides: speed, protein, and simplicity.
Rapid growth — Duckweed can double its biomass in 24–48 hours under optimal conditions. That’s faster than soy, rye grass, alfalfa, or most forage crops.
High protein content — Depending on species, protein ranges from 25–45%, comparable to soy meal.
Low resource demand — It grows on shallow water with minimal inputs, making it ideal for marginal land or integrated farm systems.
Environmental benefits — It absorbs nitrogen and phosphorus, helping clean agricultural run-off.
For UK farmers facing tight margins and environmental regulation, this combination is compelling alongside the cost of deployment on fields too dry to cultivate and plant.
An existing setup
Scalable
It has been done before at scale. One of the most notable large‑scale experiments happened in the 1980s–1990s, when Nestlé supported duckweed cultivation systems in parts of South America, especially in Peru and Colombia.
Here’s what that system looked like:
Integrated lagoons — Farmers built shallow ponds fed by nutrient‑rich water from livestock or food‑processing waste streams. These can be simple plastic channels laid on the ground
Continuous harvesting — Duckweed was skimmed daily, dried, and mixed into feed for pigs, poultry, and fish.
Circular nutrient flow — Wastewater fed the duckweed; duckweed fed the animals; animals produced manure that fed the lagoons.
Low‑tech, high‑yield — The system required minimal machinery, making it accessible to smallholders.
Results: Farmers reported improved feed efficiency, reduced reliance on imported feed, and cleaner water leaving the farms. Nestlé’s interest was tied to stabilising local supply chains and improving sustainability metrics long before ESG became mainstream.
The UK can borrow heavily from this model — but with modern upgrades. The author has since 2015 been involved in providing project vision and supporting the design of Duckweed schemes in Peru, Jordon, South Sudan , India and other countries with water and food poverty.
Why Duckweed Fits the UK’s Agricultural Landscape
The UK has several structural advantages that make duckweed adoption easier than in many countries:
Abundant rainfall → consistent water availability for ponds. Our warmer wet winters deliver that water.
High livestock density → steady nutrient streams for duckweed growth.
Pressure to reduce soy imports → duckweed offers a domestic alternative.
Strong research institutions → ideal for optimising strains and systems including Brymore Academy.
Contractors and farmers able to install the systems quickly and efficiently.
No Effluent
Duckweed can be integrated into:
Mixed farms — where nutrient flows are already diverse.
Dairy farms — using slurry lagoons as growth beds.
Poultry operations — replacing part of soy meal.
Aquaculture — especially trout and carp systems.
How do you produce Duckweed?
at the most basic level a channel/ raceway with a water containing nutrients being being forced around a channel with Duckweed growing on the surface. 25% is harvested every day.
The plan shows a typical closed circulating raceway,
Growing medium can be water with added nutrients or effluent containing nutrients that duckweed will clean as part of the duckweed production process.
How do you feed livestock with Duckweed?
collect it daily,
a quick wash, using water you have already cleaned.
press to remove free water and it can be fed wet directly to livestock.
No complicated machinery and what equipment is needed can be fabricated by a competent local fabricator.
Duckweed will clean water
Duckweed is a fast-growing aquatic plant that naturally purifies water by absorbing excess nutrients, heavy metals, and other pollutants, making it an effective and sustainable water-cleaning solution.
It can clean effluent. Be used as sewage treatment plant because it converts nutrients to high protein biomass.
Mechanisms of Water Purification
Duckweed, belonging to the Lemnaceae family, cleans water primarily through phytoremediation, where it absorbs contaminants directly from the water column. It rapidly takes up nitrogen and phosphorus, which are major contributors to algal blooms and eutrophication, effectively reducing these nutrients by up to 63–65% in wastewater over a few weeks earthecobalance.com+2. The plant also absorbs ammonia, heavy metals, boron, and organic chemicals, helping to protect aquatic life and improve water quality earthecobalance.com+2.
Physical and Ecological Benefits
Duckweed forms dense mats on the water surface, which block sunlight and suppress algae growth, improving water clarity and oxygen levels biologyinsights.com+1. Its small root systems stabilise water, reduce turbulence, and allow suspended solids to settle, further enhancing purification biologyinsights.com. By trapping pollutants in its biomass, duckweed acts like a natural sponge, though regular harvesting is necessary to prevent re-release of stored contaminants earthecobalance.com.
Applications
Duckweed is used in wastewater treatment systems, agricultural ponds, and small-scale fish farms, offering a low-cost, environmentally friendly alternative to chemical treatments. It can remove up to 84% of chemical oxygen demand (COD), 87% of total nitrogen, and 85% of total phosphorus in controlled studies, demonstrating its effectiveness in both municipal and rural settings impress-he.eu. Additionally, harvested duckweed biomass can be repurposed as fertiliser, animal feed, or even human food, adding value to its water-cleaning role earthecobalance.com+1.
Summary
Duckweed is a multifunctional, sustainable solution for water purification. Its rapid growth, nutrient absorption, and pollutant-trapping abilities make it ideal for improving water quality in ponds, rivers, lakes, and wastewater systems, while also providing ecological and economic benefits earthecobalance.com+3.
There cannot be a crisis because if there was we would be doing something different because that is what a crisis demands.
The UK has a manufactured housing shortage. Building houses caused it. Building more houses won’t solve it. This is because unlike Europe and other advanced nations the UK to all extents and purposes exclusively builds low rise car dependent houses colloquially known as “single family homes”. Built exclusively for the ambulant car owning sector of the population. It is a narrow housing offer based on a post war Boomer demand that is now over. However sufficient demand exists as much of our existing 26M houses is blocked by ageing Boomers with no realistic option to move somewhere more appropriate and stay within their community.
Some Background
Demographics, technology and the desire/ need for non car dependent lifestyle is ignored by UK politicians and developers alike. In Europe apartments make up 40 -60% of homes. It is probably no accident that the countries now struggling the most are those with a similar car-based low rise housing model. US, Canada, Australia and New Zealand. Countries wedded to the idea of the shortcake house with a lawn back and front.
It should not be a surprise that advanced states such as Germany, New Zealand and California are squeezing out houses and in Germany even considering banning them. Yet in the UK we trumpet and pursue this form of housing seemingly happy to be the world’s worst outlier in terms of housing. No state is as bad as the UK. No state so self-disillusioned to believe that its housing offer is the right one. No state happier pouring mindless volumes of concrete into the ground. No state placing ever greater demands on the future generation when its then smaller tax base will struggle even more than it does today. It is not as if we don’t have a choice. We do but seemingly don’t care about the future just today. Politicians gullibly support national house builders and fail to ask them why we have ended up where we have.
With a new government seemingly devoted to nett zero we have now arrived at The UK Housing Paradox.
“Pursuing Nett Zero whilst choosing to build Europe’s least sustainable housing (2x the EU average embodied carbon) that maximises embodied and operational carbon, transport poverty and car ownership.”
If there wasn’t choice maybe there could be some justification but there is and there isn’t.
Houses (Single Family Units)
Houses are expensive and even the UK’s smallest and cheapest is expensive compared to an apartment not withstanding that every house requires a piece of road in front of it. The UK ones are appallingly expensive, appallingly small and of equally appalling quality.
Apartment blocks need much less infrastructure in terms of highway, services, drains than houses. It is little wonder that not only are UK houses more expensive they have 2X the embodied carbon of the average EU Home. Houses generate more CO2 than apartments as the graph below shows.
What is clear that whilst other countries developed and broadened their housing offer the UK housing offer remained with a few noticeable city exceptions at 2 story’s. Medium rise (5 – 10 story) housing makes up between 40-60% of European countries housing offer. Affordable housing where a car was not necessary to live there. If you can afford a car you dont need affordable housing. A client recently noted that it was easy to spot UK affordable homes as they were the ones with new or expensive cars on the driveways.
Historically the UK housing model was largely the invention of London’s railway companies who invented the suburb. Expanses of low-density low-rise identikit houses. The result is that London has a population density less than half that of Paris. It was a model followed post WW2 and suited the Boomer generation and did not require skill or planning to deliver it and most importantly the least working capital. It fitted the British anti investment mentality. The pattern was set for the problem we have today.
Why didn’t it change?
About 40 years ago a property developer and fellow college student explained that what the UK builds is the most profitable for the developer (why would you build something that wasn’t?). Even a terrace is avoided.
The reasons are simply and solely for the benefit of the developer.
It requires the least amount of working capital to develop a site. Apartment block and terraces needed to be finished before sales are completed. A house requires far less money before the investment is recovered.
Production of houses can be adjusted to suit changing market conditions. The procurement system allows work to be stopped and started as required.
Sites need to last 3-5 years whilst the next one is brought online; the sales/build rate is throttled by price adjustment to ensure that presence is continually maintained.
It is a low-tech winning formula that makes money.
There is almost no product liability associated with individual houses.
The result is houses. Lots of houses and little else. A sea of houses best summed up by an Italian colleague who on first seeing a UK housing estate remarked. “so many buildings so few people”. Houses are built only for profit and a narrow customer band. Developers are simply mining a diminishing market leaving people trapped in the houses they have previousl built over the last generation or two. It is little wonder that housing developments that offer nothing for the local population are so ardently resisted.
Two graphics below that both compare the UK with Europe illustrate the problem.
The first is from the Financial Times using ONS data on housing.
The simple fact is that Europe has a wider housing offer with a lower financial entry level that is cheaper, faster and more sustainable to build. It is not a difficult correlation to make that countries with a higher proportion of apartments have less of a housing shortage. Our “only houses” offer is the problem. Building more of a failed solution is not going to fix the shortage.
Instead, we Brits satisfy “The definition of insanity is doing the same experiment and expecting different results.” ― Albert Einstein where we continue to perpetuate the construction of expensive carbon max (2X European average) pokiest housing where you have to own a car to live there.
The consequence of the narrow UK housing offer is that
We have a shortage of affordable housing. It is madness to build affordable housing that still requires the occupant to commit 25% of their gross income to owning a car. Affordable cars that with will disappear with the last petrol and diesel cars (circa 2040) a mere 15 years away.
It encourages house blocking compared to first world countries like Europe where there are generational options through life. There is no obvious progression from house to non-car dependent spacious apartment. We need housing close to established transport and amenity hubs and where no new infrastructure is required. Reusing existing embodied carbon economically and climate wise is the obvious best option. Yet we build the opposite. We could do it but we choose not to because those solutions rightly dont provide the maximum profits.
The idiocy of the UK solution is the constant need to build schools as the older population blocks housing in school catchments. Converted schools litter the countryside.
The average UK house has 1.2 cars per household. About 10T of embodied carbon plus operational carbon per house.
The need for avoidable roads. Roads that use oil-based binders to create the surface. There is no credible alternative yet in sight. Will we return to cobbled roads and pavements?
Income that could be diverted to jobs, diet, a healthy lifestyle and maintaining the economy of our high streets is instead used to pay for power, car insurance and loans. As an example, the cost of running a UK car is around £4K per annum, £5k before tax. If 1M non car dependent homes were built this would potentially release £5B a year into local economies notwithstanding the reduced demand on the NHS that a better lifestyle and greater disposable income would bring.
Houses won’t solve the housing problem because
Changing demographics, old people don’t drive or do stairs.
People want or can only afford car free lives.
Nimbyism. They meet planning resistance because nobody sees the benefit. It just more of the same.
Housing estates require new roads and infrastructure before house construction can start.
A thought:
The UK has 30M largely car dependent houses. Many of those built after WW2 and before 1976 are low quality and vulnerable to climate change. Between 1946 and 1979, a total of 5,804,150 houses were built in the UK.
Cornish Type 1 – worth keeping? No.
Observe the sagging ridge lines and know about the shallow foundations and well documented floor defects of these houses and bungalows and we know they are well past their design lives. The original TRADA roofs designed for light clay tiles are simply not up to the addition of PV (solar panels and insulation) let alone retiled with concrete tiles. A perverse action undertaken by many authorites where perfectly good clay tiles are replaced with concrete tiles. The recovered clay tiles then recycled to new expensive 3 and 4 bed houses.
It is irrational to try and improve such old buildings. The argument for improvement rather than a wider holistic consideration of housing in the move to nett zero seems vested in self-interests. Academic support of improvement of the existing housing stock ensures the perpetuation of the greenfield development model. We apply ridiculous values to the minimal embodied carbon of these houses and bungalows whilst building carbon intensive roads and bridges and massive concrete foundations under houses whilst the superstructures decrease in weight.
What these old buildings do have is roads and infrastructure. Usually within 1 or 2 km of the nearest amenity and transport hub. Built and ready to go. These houses and bungalows represent land that could be rapidly exploited. Require little planning effort and exploit the changing trends of demographics and society.
No complicated 106 agreements needed when the development consists of 4 or 5 properties assembled by the owners. 5 homes become 30 in 6 months. Why the owners? Because with £5.5T about to move generations as the Boomers die out why not harness that money with an inheritance tax concession that gives the whole country a stake in the solution rather than housebuilders shareholders.
How many homes do we need?
The UK estimates that we need 300,000 homes a year. That is 3M for the next 10 years.
In addition to our normal housing demand, we might expect to see a further 30M MENA climate migrants (400M are running out of food water there) come to the UK. In order to house our population, we probably need around 15M homes. 30 to 40% wont drive.
Personal Transport
As we become too old and too poor to drive options like Zoox autonomous cars will become the affordable pay as you go transport of choice. It will drive the change that should already be happening.
This apparent conflict is simply the result of the narrow UK housing offer.
There are two misconceptions in this artifical war.
1) A bunch of old people hold up the provision of new homes is perhaps the greatest misrepresentation of the housing industry. It is simply not true. The houses the Yimbys want and need already exist. What doesn’t exist is the route for the older parts of our society to get out of them and make them available whilst remaining in their communities.
2) Developers are some sort of benevolent altruistic organisations trying to solve the housing shortage. They are not. The shortage of affordable housing has been manufactured by the UK industry in order to maximise demand for the most profitable product – the 3 and 4 bedroom house.
The trick to freeing up housing in a community is not to build for the young but for the older increasing segment of society and those who would live car free lifestyles. The migration of the house blockers would provide the homes the Yimbys want.
What developers get from this conflict is to build more unnecessary but profitable 3 and 4 bed houses with government clearing away dissenters.
Rural Housing
There can be nothing more entitled than the demand for rural housing.
In the UK there is almost no need for anyone to live in the country. Across Europe we have seen the countryside empty. Not so the UK where it is nothing but a lifestyle choice; one that is subsidised by the urban population many of who are less well off than those that now live in the countryside. A situation that has reversed in the last 50 years due to the availability cheap of fuel and cars. A situation coming to an end and time for the countryside to return to its industrial agricultural use and become once again somewhere to escape from rather than a theme park to escape to.
Why subsidised? So called rural dwellers pay the same for utilities, water, they drive farther and have greater operational carbon footprints. How is it possible that a rubbish bin costs the same to empty in a village than a city estate? It is not possible.
Not only is rural housing environmentally and carbon wise the worst housing solution but Governments that seeks nett zero support this worst housing of all with additional financial support. Rural Housing maximises embodied, operational carbon and transport poverty. It seems to have missed the policy makers attention that universal car ownership will fall dramatically and many lifestyles dependent on cheap cars will no longer be viable. Politicians need to travel beyond the M25 occasionally.
A solution
Most countries dont see houses as a solution and neither should we. We need to stop building houses, increase the density of our population and not continue to build what amounts to some form of future open prison as demographics, migration and decreasing car ownership reshapes society.
Replacing 3M of our substandard houses each with 6 apartments would generate the housing we need. Avoid 3M upgrade costs and create +15M new homes. This would save around 23,000 Km of new roads. 36M Tons of embodied carbon. It would create a fair and more inclusive society, yet no politician seems able to grasp simple demographics.
Imagine
15M homes (apartments) that would not require a greenfield site to be used or a new road to be built. It would reinvigorate our high streets using disposable income from carbon saving focused on local businesses.
15M apartments that would still leave the UK almost at the bottom of the EU table where the ratio of apartments to houses is concerned
The Severn Estuary Forum met for its annual meeting 2017 in Bridgwater, Somerset on the 5th October following hard on the heels of Question Time and the Antiques Road Show at the McMillian Theatre.
An event to see people working together to resolve climate change, flood risk and wildlife preservation it was not.
Richard Hickmet the High Sheriff of Somerset opened proceedings.
The day was split into three sessions and some notes on the highlights follow.
Energy and Climate Change
Session Chair SDC councillor Ann Fraser MBE introduced the session noting the increased trade (marine aggregates) going through Dunball now rising to 70,000T per year as a reflection of increasing economic trade. Fortunately, Ross Edwards in his following update on Hinkley Point C (HPC) noted that their aggregates jetty being built as part of the enabling works was still underway. The real reason for Dunball’s growth was more to do with HPC immediate need rather than some wider reason. The irony of the councillors assumptive claim was not lost.
Ross Edwards (EDF) was able to explain, whilst maintaining a serious face, the extreme lengths that EDF were going to protect the beach from the small feet of a jack up barge and a few discreet foundations. Yet another large corporate organisation feeling the need to succumb to the irrational demands of the modern environmentalist. He also noted that EDF had spent £20M on road improvements as part of the HPC project enabling works.
Dr Judith Wolf of the National Oceanography Centre in Liverpool provided a fascinating talk that actually dealt with the session subject. The moderating impact of the edge of the continental shelf in dissipating energy should make us all worry a little less about that large piece of a volcano that threatens to slide into the sea in the Canaries at La Palma causing a tsunami. The great flood of 1607 also got a brief note and it was not a tsunami.
What was more important was Dr Wolf’s comments on global warming and the best scenario of sea level rise being 0.5m and the worst at nearly 2.0m. Dr Wolf confirmed they really don’t know the figure as no one knows how the melting polar ice caps will impact on the world. It was received with little or no comment. 2.0m is around twice the figure that the EA is using for the Bridgwater Tidal Barrier (BTB).
Planning Governance & Flood Risk
Andy Hohl (EA) project manager of the Bridgwater Tidal Barrier project explained the mechanism of the floodgates but avoided the mechanism of the planned flood defence system. A diagram was shown showing the planned flooding of Chilton Trinity and Pawlett Ham’s when there is coincident high tides and storm surges. It is an event that will increase in intensity and frequency as sea levels rise and after a few events will have poisoned the land.
River Parrett at Chilton Trinity and Pawlett Hams; EA flood model Bridgwater Tidal Barrier 5th October 2017; How the River Parrett will increasingly flood the Levels
The EA missed the opportunity to explain why a tidal barrier is to be built in Bridgwater rather than the conventional locations at the mouth of rivers such as at Newcastle and Barking.
Mr Hohl was asked what comes after rising sea levels makes the Bridgwater Tidal Barrier ( gate and river banks) ineffective in protecting the area from the sea. Apart from some irrelevant comments about things being done today, there was no answer about tomorrow. Tomorrow, if Dr Wolf is correct, will be only 50 and not 100 years away before a replacement solution is needed.
Wessex Water’s Lucy George gave an interesting talk on the construction of the new sewers being built around Bridgwater. Clever engineering in bad ground.
Protected Sites and Species
Alys Lavers the WWT manager at Steart gave an update on the last 3 years entitled Climate Change, Flood Risk and Community Action. It has obviously become a go to place for students studying for degrees and PHD’s. Even some elver’s have apparently decided it’s a great place deciding that the swim to Oathe and the freshwater rivers of the Tone, Yeo, Parrett and beyond was simply not worth the effort and turned right into the Steart reserve. Whether that was in the EIA and is safer than getting past the locals elvering is no doubt a study in itself. However a look at the IDB asset map apparently showing every route to freshwater blocked by a clyce does not paint a promising future for the lost elvers.
Ms Laver was also remarkably candid about Steart. That there would be no facilities built there apart from the existing toilets. No chance of a place to shelter from the elements and have a cup of tea. Little chance then that Steart will deliver the promised economic contribution when planning permission was sought by the EA. Someone in the audience from Burnham on Sea said it was difficult to find and Ms Laver explained that the lack of signposting was deliberate. Apparently keeping the number of visitors down was done for the benefit of the locals.
What was apparent to many in the audience was that WWT Steart is really only interested in the right sort of visitor; academia and other suitable people. The ordinary taxpayers who paid for Steart from their taxes (that is where the EA get its money from) most definitely not welcome.
Rob Shore WWT, session chairman and coordinator of the Severn Vision introduced the document that was first published in January 2017. What is interesting is the ambition of this recent document. A saltmarsh from Dunball to Highbridge. The proposal outlined in this document is clearly in line with the EA’s and SDC’s current strategies set out in the Shoreline Management Plan and Parrett Estuary Flood Strategy.
The map below was generated from the Severn Vision interactive map. If you live around the Severn Estuary its worth checking out the aspirations of the various wildlife organisations.
Areas of Potential Saltmarsh
One cannot help but feel that the EA and various wildlife organisations including WWT have the ambition to turn the coastal part of Somerset into a wildlife theme park. Trading off the land in Somerset for planning gain elsewhere such the Bristol Ports deal where Bristol gets the economic benefit and people in Somerset beyond made to feel to feel uncomfortable in their own countryside is unacceptable. Climate change should not be used as little more than a Trojan Horse by organisations with an overblown sense of morality and entitlement.
A question on the morality of an island that cannot feed itself flooding food producing farmland to create saltmarsh was quickly pushed to one side.
Finally a question about mitigating the noise from exploding old military ordnance being found as part of the HPC outfall construction work. Ordnance, when located, is subsequently blown up by the Navy’s bomb disposal team; it did not find someone willing and able to answer it.
Observations
What was quite clear was climate change and rising sea level is really only a device and agenda for wildlife organisations to pursue the expansion of wildlife habitat.
There was no big picture presented, no key numbers and no one to provide context as to how the wildlife of the Severn Estuary, ordinary people and business might co-exist. Key local councillors present on all the flood committees, Wessex, the drainage boards and the SRA were with the exception of Ann Fraser notable by their absence. Perhaps there were no expenses paid for attendance. Councillor Fraser it was noted in the Speaker Summaries although not an engineer had been “instrumental in leading a technical review of the flood risk in Bridgwater”. The Somerset Rivers Authority is no better with regard to engineering. There is a disturbing and dangerous precedent of non-qualified people in influential positions shaping Somerset’s flood and climate change plans. Google and mobile phones do not make an expert.
There is simply no leadership or vision when we should be looking forward not 100 years but perhaps 2 to 300 years. Sea level rise is not stopping and schemes such as the Bridgwater Tidal Barrier that just look forward 100 years and stop with no apparent reason defy reason and responsibility; what is the plan afterwards? there isnt one.
Perhaps worst of all for an event sponsored by my own institution, the Institution of Civil Engineers, there were no engineers representing the many companies making money from climate change. Engineer’s created the landscape we have and the current generation should be leading process of planning for our future but seem to have abdicated their interest or responsibility in shaping the land bordering the Severn Estuary.
Somerset and the other counties of England and Wales that border the Severn Estuary need to have a serious conversation and take control of climate change issue at a regional level. The situation needs a champion with authority and knowledge.
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