Agriculture and irrigation are some of the heaviest users of water in society.
In this guide, we look at ways we might use water more sustainably and efficiently in these areas.
Summary – Using Water More Efficiently & Sustainably In Agriculture
Globally, on average, 70% of all fresh water withdrawals are for agricultural use.
Although, that % can differ from country to country
Using water more efficiently and sustainably involves looking key trends for water use, water waste, water loss and leaks, and so on
In agriculture, sustainable water solutions can be complex, and will need to be customized to geographically local conditions and factors.
But, there’s a number of key things we might focus on for more efficient and sustainable water use …
– [Paying specific attention to where we waste and lose water, in addition to how much water, and the ways we use water in different sectors like agriculture are important]
– Irrigation is perhaps the main area water sustainability can be improved in agriculture.
Improving water efficiency of irrigation systems, minimising waste that happens via certain irrigation systems and factors like evapotranspiration and runoff, and fixing leaks, can all help
– Some countries use far more irrigated water and waste far more water in their irrigation systems than others, so these countries may be a main focus.
Pakistan, China and India for example use over 50% of total irrigated water in the world according to some reports
– Water pollution from agriculture can be reduced and will provide more available water in the long term
– There can be political and financial barriers to better water sustainability in agriculture
– We might look at how we can better re-use water in agriculture – such as run off from irrigation
– We might look at how we use other sources of water like desalination and treated waste water from other industry to water crops
Sustainable farming practices that improve things like soil health can help with things like water retention
We can look at water intensive agricultural products like beef, animal meat, and some beverages like soda, fruit juice, rice paddies, sugar cane, cotton, etc., and consider if water conservation is critical enough in some regions to produce other products, or import products instead.
Some of these products, like cotton in some parts of India, also use a far higher % of irrigated water than other crops in other parts of the world
– Climate and growing conditions on a farming plot of land can also make a difference – hot and dry conditions can use far more water than say for example cooler climates or places where rain fall is common
– Reducing food waste at the consumer level can help indirectly decrease the water waste in agriculture
– New technology such as GMOs may help with water sustainability in agriculture
– Overall, the use of new technologies and sustainable water management processes, as well as strategies tailored to the local conditions, crops, and farmers will be required to address agricultural water sustainability.
Why It’s So Important To Use Water Efficiently & Sustainably
Some of the main reasons include, but aren’t limited to:
Additionally, water withdrawals and demand in agriculture and for food production is expected to increase in the future with a growing world population.
How Much Water Do We Use In Agriculture?
Developing and low income countries use more in agriculture (up to 90%) and developed countries can use up to and over 50% on industry and power generation.
It makes sense that agriculture (and irrigation) firstly, and industry/power generation secondly is where we might waste and lose a lot of water.
Each country, region and city in the world will lose and waste water in different ways and in different shares.
Where Do We Use & Waste The Most Water In Agriculture?
Irrigation is one of the biggest causes for loss and wastage of water in agriculture
It is estimated that 40-60% of all water used for agricultural irrigation is wasted due to runoff into waterways, evapotranspiration, field flooding
Almost half of the total area being irrigated worldwide is located in Pakistan, China and India
Currently … 60 percent of the water diverted or pumped for irrigation is wasted—via runoff into waterways or evapotranspiration.
– worldwatch.org and globalagriculture.org
How We Might Use Water More Efficiently & Sustainably In Agriculture (Potential Solutions)
Some of our notes about solutions:
– Irrigation is perhaps the main area in agriculture where water can be used more efficiently and sustainably
– Look at which irrigation systems and types best balance performance/effectiveness and water sustainability.
There’s different irrigation types to look at such as center-pivot, drip/micro irrigation, flood/furrow, spray/sprinkler, sub irrigation, and surge flooding (usgs.gov)
– When comparing flood vs spray irrigation for example – ‘[In the US] Flood irrigation is not the most efficient irrigation method, but it is cheap and low-tech. On the one hand, less water is lost to evaporation than in spray irrigation, but on the other hand, more water can be lost from runoff at the edges of the fields.’
Some efficient surface irrigation techniques farmers use are levelling of fields, surge flooding, and capture and reuse of runoff. (usgs.gov)
– Address water waste from irrigation (waste occurs via runoff, evapotranspiration, and so on – it can be avoided in some instances)
– Address efficiency of irrigation systems (how much water they use, but also adjust how precise and effective they are, along with features such as timers, sensors, software, and so on)
– Fix leaks and points of water loss in irrigation systems
– Use different irrigation systems and consider flood irrigation (and field flooding) vs drip irrigation methods
– Address political and financial barriers that make it difficult to address water sustainability in farming (such as upgrading irrigation systems and renewing distribution networks)
– Consider how using alternatives fresh water sources like harvested rain water, and treated waste water can ease the burden on surface water and ground water sources for irrigation
– Consider how agricultural water users not paying the true supply cost of water might be leading to wasting or over consumption of water
– Consider the benefits of implementing sustainable farming techniques and methods vs conventional farming techniques and methods
– Consider how improving soil health can help with things such as water retention in soil, and other water conserving benefits
– Other sustainable farming methods and techniques might involve growing a diverse array of crops suited to local conditions, practicing agroforestry or growing perennial crops, applying organic fertilizer, and growing cover crops
– Consider how water pollution and contamination by the agricultural industry can be reduced (fertilizer runoff, pesticide use and livestock effluent degrades water resources and leads to less available water to use)
– Consider creating government incentives and penalties for the biggest and smallest, and most efficient and least efficient agricultural water users
– Governments should assess existing policies and regulations for agricultural water use and consider how they support excessive water use and agricultural water pollution
– Consider how funding, investment, training and support can be offered to farmers with increasing water sustainability.
Subsidies, rebates, grants, etc. are all options to look at as well
– Consider how farms can become holistic with their water use and water recycling e.g. can run off from crops be treated for contamination, and be re-used?
– Consider how rain fed farms can better be utilized in the future
– Consider the impact of producing agricultural products in certain climates, and whether there is any benefit to certain States/provinces, or countries, importing certain agricultural products instead to save water
– Consider which agricultural products are the most water hungry, and consider whether less water hungry agricultural products can be produced or grown instead
Beef in particular is an agricultural product that has a large water footprint, specifically for growing animal feed.
What are the pros and cons of changing the beef industry, or reducing beef products?
– Crops like rice paddy, sugar cane and cotton can be water hungry in some places
– Water on it’s own tends to have a lower water footprint than beverages like soda, beer and wine, juices, coffee and so on – so, water may be a more sustainable drink option
– In regions where ground water is being depleted for agricultural water withdrawals, consider augmenting water supplies to lessen the burden on ground water to supply water resources
– Certain countries and regions in the world also withdraw or consume far more water for agriculture, or have characteristics like far higher evaporation rates for irrigated water (due to high temperatures), or higher rates of leaks in irrigation systems due to leaks in the water supply distribution networks – so, each country and region should focus on unique areas of unsustainable water management
– Reducing food waste at the consumer level has the effect of indirectly reducing water waste (of the irrigated water used to produce the food)
– Educate the general public, and school children on water withdrawal and consumption in the agricultural sector
– Provide more transparent information to the general public on GMO crops and food items and their potential to decrease water consumption compared to conventional crops and food (public trust in GMOs is currently low – despite scientific opinions being favorable on the safety of GMOs)
– Explore how public/private partnerships can help with making water efficiency/sustainability solutions be delivered to market and work properly (for example – companies that provide irrigation technology)
– Address other environmental issues a changing climate, that have the ability to affect the amount of freshwater available to farmers a changing climate can impact growing conditions and precipitation patterns)
– See that holistic ecosystems are working in other industries together as they should be to maximise water efficiency (Good examples of holistic management are communities that operate sewage treatment plants while pursuing partnerships with clean energy producers to use wastewater to fertilize algae and other biofuel crops. The crops, in turn, soak up nutrients and purify wastewater, significantly reducing pumping and treatment costs.)
– Consider how a growing population into the future will have an impact on the agricultural supply needed for the future, and how this growing population and agricultural supply will impact total water required for farming and agricultural produce
Other potential solutions from other sources may include …
[Increasing water-use efficiency, identifying areas of water waste and loss, and managing demand are three ways to be more sustainable with water use in agriculture and irrigation]
Increasing efficiency in irrigation … would be [one of the best and possibly most effective places to start]
… Farmers can achieve water-use efficiency gains in a number of ways [such as] growing a diverse array of crops suited to local conditions and especially in drought-prone regions, by practicing agroforestry or growing perennial crops (to build strong root systems and reduce soil erosion), by maintaining healthy soils (either by applying organic fertilizer or growing cover crops to retain soil moisture), and by adopting irrigation systems like “drip” lines that deliver water directly to plants’ roots.
In arid regions of the Middle East … an experimental drip irrigation project … in the Syrian village of Fraytan has … reduced the annual demand for water by 30 percent and increased agricultural yields by nearly 60 percent.
[Another] way … is to reduce consumer food waste [as water, land and energy is used to produce food].
Solutions to water use in agriculture are ultimately complex and locally diverse, [but some worthwhile solutions might involve]
[Reduce water pollution of ground water and water ways from agriculture – particularly agricultural fertiliser runoff, pesticide use and livestock effluents]
… governments [could create incentives for farmers to better manage water use, but also reduce water pollution from agricultural chemicals]
… [governments should] enforce existing water regulations and remove policies that support excessive use of water and polluting activities
[Governments should consider how farmers can pay for the full cost of the water they use – so water is valued as it should be, and there’s more accountability]
[Governments should look at alternative water sources other than groundwater pumping for irrigation]
… focus on [multiple policy responses at different levels, each adapted to specific water resource systems]
At a farm level, we might – Establish farm-level information systems on water resources, water quality and risks, encourage uptake by farmers of water-efficient and water risk-resilient technologies and practices, and foster better farm management practices that internalise environmental costs by means of the polluter-pays principle.
At a watershed level, governments could – Improve information systems on surface and groundwater quality and flows, help to assess risks, and implement programmes tailored to specific challenges, define property rights attached to water withdrawals, water discharges and ecosystem provision, and ensure that these sustainably reflect water availability, develop flexible and robust water allocation systems that allow both price and quantity to fluctuate – via market mechanisms, for instance – in response to seasonal conditions and shocks, and use regulatory, economic, and collective measures to control intensive agricultural groundwater use and water pollution.
At a national level, the enabling environment should be improved by – enforcing existing regulatory provisions on water use and water pollution, ensuring that sanctions and penalties are effectively imposed in the event of noncompliance, ensuring that charges for water supplied to agriculture at least reflect full supply costs, and ideally cover the opportunity cost of water withdrawals, social and adjustment policies should be used to compensate the poorest farmers or to facilitate necessary consolidation in the affected sectors, designing risk management instruments that effectively increase the resilience of farmers to the uncertainties associated with weather events and climate change, removing non-water related price-distorting policy measures, such as agricultural and energy subsidies, and fostering transparent and open markets that allow food to be produced where it is economically efficient and environmentally sustainable to do so, and that pool risks by enabling yield losses in a given region to be offset through imports.
[Being smart about the types of crops grown – water hungry vs water efficient. Rice is an example of one type of water hungry crop]
[Being smart about growing crops in dry and hot climates – can they be grown in climates where less water can be used, and less water is evaporated instead?]
[Fix leaks in leaks in the irrigation water supply distribution networks]
To solve the problem of water waste it’s necessary to introduce more modern technologies such as drip irrigation and renewing distribution networks, but often serious financial and political problems limit these options.
[Address financial and political problems that prevent upgrading of irrigation systems]
[Sustainably managing irrigation withdrawals so they don’t exceed renewable water supply rates]
[the efficiency of irrigation systems can be improved]
[field flooding irrigation alternatives might be looked at so evaporation isn’t as much of a problem]
[reduce water pollution from agriculture]
[grow less water hungry crops]
[figure out if water sharing is an option between countries- but note, countries such as the US and Mexico, and Spain and France have had issues]
[Growing crops and meat that are water efficient]
[More precision in irrigation]
[Look at alternatives to irrigation, such as rainwater harvesting, and treated waste water]
[Enhancing water retention in the soil]
Treated waste water usage in agriculture is one of the future opportunities if we can find ways of making the best use of it without risking food safety
This can be through safer irrigation, or greater hygiene at markets and also people can effectively wash the vegetables so you can get rid of most of the pathogens
[When regions within a country are experiencing dry climate conditions, water management bodies may consider restricting withdrawals for irrigation]
[1. Produce and eat foods that are less water intensive, and produce and eat less livestock meat – for example poultry might be one of the least water intensive meats per kilogram when compared with red meat and pork]
2. Farmers can use intercropping, agroforestry, and cover crops – [which is good for soil health and keeping nutrients in the soil]
3. Farmers can implement micro irrigation – Approximately 60 percent of water used for irrigation is wasted. Drip irrigation methods can be more expensive to install, but … [research] shows [it] can also be 33 percent to 40 percent more efficient, carrying water or fertilizers directly to plants’ roots.
4. Farmers can improve rainwater harvesting – making planting pits wider, deeper and filling them with organic material can help retain rainwater longer, helping farmers to increase yields even in years of low rainfall. In general, more on-site rainwater can be captured and harvested
5. Farmers can use mobile technology to save water – [such as using] mobile phones to turn irrigation systems on and off remotely. This helps reduce the amount of water and electricity wasted on watering fields that are already saturated.
6. Farmers can plant perennial crops – [which helps protect the soil for longer] than annual crops, which reduces water loss from runoff. According to a report … “annual grain crops can lose five times as much water and 35 times as much nitrate as perennial crops.”
7. Practice soil conservation – Soil conservation techniques, including no-till farming, can help farmers to better utilize the water they have available with better water retention capacity and better water use efficiency in crops
1. Grow crops that use less water – For example growing grapes and olives requires significantly less water than tomatoes or bananas. Or it can mean crops bred to require less water such as the Water Efficient Maize for Africa (WEMA) project.
Of course the choice of crops grown is also dependent on environmental and socio-economic conditions.
2. Precision use of irrigation – either by scheduling irrigation for times when the crops needs it or using irrigation only in areas needed.
Methods can include direct measurement of soil water content to inform on timing and placement, sprinkler or drip irrigation.
But issues of access to and management of water supplies can limit the feasibility of some of these techniques in some areas.
3. Use methods alternative to irrigation – such as rainwater harvesting and treated wastewater.
4. Enhance water retention in the soil – through farming methods and systems such as residue management, conservation tillage, zai, bunds, contouring and field levelling.
This will reduce the amount of water that needs to be applied to the field.
5. New technologies in the future, and investing in new technology – … new technologies such as micro-scale solar desalination units or nanotechnology hold some potential.
But … many of the solutions to agriculture’s dependence on water require knowledge, research and access to forms of innovation.
Investing in participatory research that meets the water and production needs of local farmers is therefore critical to reducing water use in agriculture and building the sector’s sustainability.
1. Using drip irrigation – helps deliver water directly to a plant’s roots, reducing the evaporation that happens with spray watering systems.
2. Using irrigation timers – Timers can be used to schedule watering for the cooler parts of the day, further reducing water loss.
Can save up to 80% of water that is used in conventional irrigation.
Can contribute to increased crop yield.
3. Irrigation scheduling – when, how often, and how much water is delivered to crops.
To avoid under- or overwatering their crops, farmers carefully monitor the weather forecast, as well as soil and plant moisture, and adapt their irrigation schedule to the current conditions.
4. Capturing and storing rainwater instead of using municipal supply water – via rainwater catchment systems, man made ponds, pits etc.
5. Growing drought tolerant crops – crops that are appropriate to the region’s climate
6. Consider dry farming – … relying on soil moisture to produce … crops during the dry season [without irrigation].
Special tilling practices and careful attention to microclimates are essential [and there’s generally lower yields].
Wine grapes, olives, potatoes, and apple trees can also be successfully dry farmed in California.
7. Consider rotational grazing – … increases the fields’ water absorption and decreases water runoff, making pastures more drought-resistant …
8. Use compost and mulch – … improves soil structure, increasing its water-holding capacity.
9. Use cover crops – … cover crops … allow water to more easily penetrate the soil and improves its water-holding capacity.
10. Use conservation tillage – [can] help increase water absorption and reduce evaporation, erosion, and compaction.
11. Consider going organic – [might help with reducing water pollution, increasing soil water retention, and recharging groundwater]
[Overall, farmers can be looking to] reduce water usage and increase crop yields [with] new water based technology to save and become more efficient with water
Some of the ways they might do this might include …
1. Flood-irrigated fields using laser-leveling technology – the sensor gathers a signal from satellites to ensure fields are cleared as smooth as possible, preventing water from pooling
2. Converting to drip irrigation, and using smaller sprinklers to reduce water waste
3. Monitoring soil for moisture content
4. Adding mineral like magnesium and also clay in soil – to help mitigate the effects of hotter temperatures [like evaporation] by reflecting ultraviolet radiation
5. Planting cover crops – to enrich the soil and using metered sprinklers to slash water use
Efforts to reduce water waste might need to come through policy [as well].
Western water rights are awarded to users on a “first come, first served” basis and typically require rights owners to use all their allocation to maintain their rights.
On top of that, most states have incomplete data on groundwater or can’t easily verify whether farmers are using more water than allowed.
California, which has poor water data, is implementing a new groundwater management law that policymakers hope will curb waste by establishing a floor for water levels, beyond which restrictions would kick in.
But even getting that system established is complicated – big California agriculture producers resisted a centralised program for data collection, instead opting for local information gathering that then must be scaled up and matched with the rest.
Cotton and alfalfa hay, used largely as feed for cattle, consume a lot of water and are often targets for criticism [of water waste]
As of 2008, farms use 12 percent less water to harvest an acre of crops, on average, than they did in 1998
At the same time, though, total water used on farms declined just under 1 percent as smaller farms consolidated into larger, more industrialised ones.
1. Make irrigation more efficient – [with no leaks, timers and sensors, drip irrigation, and so on]
2. The use of Ground cover fabrics
3. Support healthy soil – … Methods that can help to maintain healthy soil include adding compost, residue management, conservation tillage, and no tilling farming techniques.
The use of contours and swales on the farming landscape also help to hold water high on the landscape and to prevent erosion.
4. Consider using permaculture farming methods – Many permaculture farming methods, such as swales built on contour, inherently hold water on the landscape, reduce (or even eliminate) the need for supplemental watering of crops, and help to restore aquifers …
5. Growing crops that are more water efficient – Many of the commonly traded agricultural crops grown today are grown in large plots of monocultures and require large amounts of water to produce them.
By growing a variety of less thirsty crops, including perennial crops with deep roots, this should reduce the demand for water in agriculture. For example, grapes and olives are crops that require less water for production than tomatoes.
6. Grow crops suited to local climates – … For example, it makes the most sense to grow those crops in a desert-type climate that tolerate more hot and dry conditions, such as fig trees and moringa trees.
7. Utilizing rainwater harvesting – Rainwater harvesting can be used for both small and large farms for farming tasks such as herd watering and irrigation.
8. Utilizing permanent raised bed crops – raised beds are currently being used in certain countries in the developing world, such as in the Syrian village of Fraytan to produce crops that require less irrigation
9. Reduce food waste – approximately 30-40% of food that is produced is wasted.
By reducing the amount of food that we waste, we will also reduce the amount of water, land, and energy that is used to produce the food
Ideally, farmers would like to increase yield rates, lower water usage and protect biodiversity
Improved/more efficient irrigation, healthy soil and retaining rainwater appear to hold some major keys to the water issue
Modern irrigation systems … can reduce the amount of water lost through surface evaporation by 30 to 70 percent depending on crop and weather conditions [and they can also reduce field flooding]
[For rain fed agriculture, make sure the soil can retain water well through sustainable farming practices like conservation tillage and mulching]. [These things as well as] small-scale water harvesting can increase rain water infiltration by as much as 2-3 fold.
… the yields from irrigated farms are often higher than from solely rain-fed agriculture … [so] integrating a combination of rain-fed and irrigated agricultural methods to optimize the yields of crops [might be smart]
Even with optimum soil and water management, farmers will still lose crops to drought and heat if they do not have the best seeds and crop protection to carry them through inevitable dry spells.
Researchers have developed new crop varieties which are more water efficient and tolerant to heat and drought through advances in breeding and biotechnology.
[GMOs might be important for the future of water smart farming]
Today’s crop protection technologies … [such as] Plant regulator products are designed to help prevent crop loss when plants grow too tall and collapse. T
hey also provide additional benefits by reducing water needed to grow crops.
Other products are specifically designed to protect plants from moderate drought and other stresses by blocking the plant’s response to stress which increases the long-term health of plants and improves farmers’ yields.
There is no silver bullet [or one answer to sustainable water management].
But an integrated approach using the technologies outlined here and tailored to the local conditions, crops, and farmers can maximize water use efficiency.
Water efficiency measures are usually cheaper than increasing water supply through desalination [as one example]
[There should be] investment in research to develop innovative water-efficient technologies in addition to drought tolerant seeds, new crop protection products, and optimized irrigation systems for specific crops.
… farmers [have to be able to] afford, [see advantage to, and understand new technology]
Therefore, a key component of policymaking will have to include infrastructure for knowledge sharing and access to technology.
This includes access to affordable credit and financial risk-management mechanisms, such as insurance for weather-related crop losses.
… helping small farms with access to finance, guaranteed markets, technical assistance, and insurance [is critical]
Most of the water used in agriculture goes towards the irrigation of crops.
Preventing runoff from irrigation is crucial to reducing the amount of water that gets wasted.
As in farming, this runoff often contains an excess of nutrients and particulates that, if introduced to rivers and streams, can contaminate fresh water supplies.
Strategies such as using screens or mesh are options to reducing matter in wastewater, whilst diverting its flow into retention ponds where it can be reused for irrigation is an effective way to curtail the total volume used.
The outlook is positive. Australia decreased its consumption of water by 7 per cent in 2014-2015, a trend supported across the majority of Australian sectors …
Watercalculator.org has some interesting solutions and ideas for shrinking the water footprint of crops.
Rainwater harvesting, dry farming, and taking care of the soil by using low or no-till practices, using crop rotations and planting cover crops to replenish soil naturally are some solutions discussed.