The Uses Of Water In Agriculture

Water monitoring is becoming crucial as agricultural droughts become more common and the global population rises, and solutions are needed to feed everyone with less water. By learning precisely how water flows through agricultural systems from water system to field to crop to runoff, farmers can make decisions that maximize efficiency for every drop.

Water is, in fact, the most critical input in the modern agricultural puzzle. In a system where efficient water management practices can influence global food security, every drop counts. 

Whether you are a commercial farmer, a small-scale organic producer, or an agricultural consultant there are ways that you can assess how water is being used within agricultural systems to better inform decisions about water management and monitoring.

In this article, we will look at the various roles of water within agriculture, outline the complexities of agricultural water management, and reveal how monitoring technology is driving efficiencies in water use throughout farms all around the globe.

The Agricultural Global Water Challenge

We know that around 70% of all freshwater withdrawals worldwide are used for agriculture, which makes it the leading consumer of the planet’s finite water resources. With the continued growth of the global population—a figure we’re on track to see reach nearly 10 billion people by 2050, the pressure is only going to increase on agricultural water. This puts a lot of pressure on farmers to use water efficiently while maintaining or even increasing productivity.

The numbers are alarming – just 0.5% of Earth’s water is usable freshwater, and climate change is pushing the availability of that supply even lower. Nearly 2 billion people around the world are without safe drinking water, and roughly half of the global population has experienced severe water scarcity at some point. These challenges position water monitoring, conservation, and management as an integral pillar for sustainable agriculture.

The Main Applications Of Water In Agriculture

Irrigation

In agriculture, irrigation is the largest scale usage of water and it accounts for the major part of water spent in agriculture sector. There are several types of modern irrigation systems, each offering different advantages and levels of water efficiency:

• Drip irrigation: A network of valves, pipes, tubing and emitters delivers water directly to a plant’s root zone. This precision method can lower water consumption by up to 50% when compared to traditional techniques while enhancing yields through maximum moisture conditions.
• Sprinkler Irrigation: Water is supplied through pressurized tubes and sprayed over crops via sprinkler heads. Sensory and automated controls help maximize distribution networks and limit wastage.
• Flood Irrigation: Water passes over fields via furrows or basins. However, this practice is often water-intensive compared to other forms of irrigation and creates a lot of runoff.
• Center Pivot Irrigation: The very large systems of sprinklers rotate around a central pivot point, creating the distinctive circular crop patterns that can be seen from the air. More sophisticated systems incorporate variable rate technology to deliver different amounts of water to different sections, based on soil moisture data.
• Subsurface Irrigation: Water is delivered below the soil surface, which ensures minimal evaporation and maximum efficiency.

The selection of an irrigation system depends heavily on multiple factors ranging from the type of crop being grown, environmental factors such as soil types and climate conditions, water availability, energy costs, and available technology. 

More recently, farmers have adopted precision irrigation systems that use real-time monitoring information to inform their irrigation decisions.

Livestock

Water is an important component of all livestock production and performs many critical functions:

1. Drinking Water

All livestock need access to fresh, clean drinking water on a daily basis. The amount required is very different per species, size, production phase and environmental conditions.

For example:

• Water for a dairy cow in production can be as high as 30-50 gallons of water a day
• Most beef cattle require 8-20 gallons per day
• Pigs need 2-5 gallons a day
• Chickens consume about 0.05-0.1 (gallons/consume per bird) per-day

2. Cleaning Facilities

Barns, milking parlors, processing areas, and equipment are washed down to maintain sanitation and prevent disease, a process that relies heavily on the use of water.

3. Animal Cooling

Sprinklers and misters to cool livestock during high-heat days, also prevents heat stress especially on dairy and swine operations.

4. Feedstuff Production

The production of feed crops and forage uses substantial water indirectly through livestock.

Agricultural Operations

1. Frost Protection

When water has been applied and air temperatures drop below 32°F (0°C), this water will freeze, forming a protective coat of ice, keeping the tissue temperature at 32°F (0°C), preventing injury from lower air temperatures. This is a common technique in fruit orchards and vineyards.

2. Crop Cooling

Under very high-temperature conditions, water is pumped through irrigation systems overhead, so that it evaporates as bean temperature decreases, preventing heat damage.

3. Soil Leaching

Water is applied to remove excess salts from the soil profile, especially in arid regions where salt buildup would impede plant growth.

4. Pesticide & Fertilizer Application

Water acts as a carrier for agri chemicals and nutrients, enabling their controlled application as well as distribution within the area.

After Harvest 

1. Washing & Cleaning

Freshly harvested produce is washed to eliminate soil, debris, and potential contaminants in advance of processing or marketing.

2. Cooling

Water is used to quickly cool freshly harvested crops, especially leafy greens and other perishables, thereby prolonging shelf life and quality.

3. Transportation

Water acts as a medium for collection and transportation of some crops like cranberries which are grown in flooded fields.

4. Processing

Food processing activities need large amounts of water for cleaning, cooking, blanching, and other preparation methods.

Specialized Agricultural Systems

Hydroponics & Aquaponics

These soilless growing systems are among the most water-efficient types of agriculture available:

1. Hydroponics

In hydroponic systems, plants grow with their roots submerged in water infused with nutrients or an inert medium such as coconut coir or rock wool that’s periodically drenched with nutrient solution. 

Recirculating hydroponic systems use 90% less water than conventional field agriculture whilst producing more yields.

2. Aquaponics

It is the combination of aquaculture (raising fish) with hydroponics in a symbiotic environment. Plant roots filter the water for the fish, and fish waste acts as nutrients for the plants.

These systems in a closed loop are also extremely efficient and use approximately only 10% of the water as compared to traditional farming methods. 

Rice Cultivation

Rice cultivation is unique in its water needs:

1. Paddy Flooding

In classic rice production, fields are flooded to depths of 4–6 inches and then drained during most of the growing season, resulting in iconic rice paddies that dot the Asian landscape and many other rice-producing regions.

2. Alternating Wetting & Drying (AWD)

A more recent method that alternates between flooding and allowing the soil to partially dry can increase water use efficiency without compromising yields.

3. System of Rice Intensification (SRI)

SRI is an integrated system involving water management techniques which enable up to 50% water saving compared to conventional paddy cultivation.

Specialty Crops

Specialty crops also have special water needs:

• Cranberries: These berries are cultivated in bogs and flooded for harvest and protection during winter.
• Watercress: This green is grown in water, typically in beds constructed to allow for a continuous flow of fresh water.
• Taro & Water Chestnut: These crops grow, partially or fully, submerged in water for most of their life cycle

Agriculture: Water Quality Helps Guide in Decision Making

Besides that, water quality is equally as important as quantity for successful agriculture. Various agricultural applications have their requirements in terms of quality, and it is important to monitor these parameters:

1. pH Value

Most of the agricultural water use has an optimal pH range of 6.0 to 8.5. Soils tend not to be able to carry water much outside this range before water impacts soil chemistry, nutrient availability, and the effectiveness of agricultural chemicals.

2. Electrical Conductivity (EC)

This is a measurement of the salinity or total dissolved solids in the water. Different crops have different levels of tolerance:

• Low EC (< 1.0 mS/cm): Good for salt-sensitive crops such as strawberries
• Medium EC (1.0-3.0 mS/cm): Suitable for vegetables and field crops
• High EC (> 3.0 mS/cm): The EC is only suitable for salt-tolerant crops

3. Dissolved Oxygen (DO)

In aquaculture and hydroponic systems, DO (typically 5-14 mg/L) is especially important for the health of root systems and microorganisms.

4. Micronutrients

Iron, manganese, zinc, and copper are trace elements needed for plant development, but can be toxic in higher concentrations:

• Fe (Iron): Required for chlorophyll production; 100−500 mg/kg.
• Manganese (Mn): Critical in the photosynthesis process; desirable 50-200 mg/kg
• Zinc (Zn): Enzyme function; balanced 2.5-5.0 mg/kg
• Copper (Cu): Supports root development; Ideal Value 0.8–2.0 mg/kg

5. Biological Pollutants

The presence of pathogenic bacteria, blue-green algae and other microorganisms can have an impact on crop health and food safety.

Agricultural Water Monitoring Technology

Economically, modern agriculture increasingly adopts advanced monitoring technologies to maximize water usage. These systems offer real-time information about water quantity and quality, which enables precision management decisions:

Soil Moisture Monitoring

1. Capacitance Sensors

Contain 2 probes which create an electric field. The sensors can be installed at several depths to cover the moisture profile throughout the root zone.

2. Tensiometers

These probes measure soil water tension, the effort that plants have to make to pull water out of the soil.

3. Neutron Probes

They are the most professional types of soil moisture measuring instruments, using the principle of detecting hydrogen atoms in soil, they can provide the most accuracy in measurement considering the whole profile of soil.

4. Time Domain Reflectometry (TDR)

This technique uses electromagnetic pulses to accurately measure soil moisture content.

Water Quality Monitoring

1. pH Sensors

Continuous monitoring of whether the water is acidic or basic maintains ideal conditions for nutrient availability and chemical effectiveness.

2. Electrical Conductivity (EC) Meters

Measure salinity in irrigation water and soil solution to avoid salt build-up.

3. Dissolved Oxygen Sensor

Important for aquaculture, hydroponics, and evaluation of biological activity in water bodies.

4. Nutrient Sensors

Track key nutrient levels such as nitrate-nitrogen and ammonium-nitrogen to optimize and avoid fertilizer runoff

5. Temperature Sensors

They measure water temperature, which influences dissolved oxygen levels, chemical reactions, and biological activity.

Monitoring Water Flow & Distribution

1. Flow Meters

Measure the quantity of water flowing through irrigation systems, assisting in tracking usage and identifying leaks.

2. Pressure Sensors

Help you monitor pressure in irrigation lines to make sure the system is working correctly and is distributing water efficiently.

3. Weather Stations

Providing data on rainfall, temperature, humidity, and evapotranspiration rates to enable decisions regarding irrigation scheduling.

4. Remote Sensing

Using satellite and drone imagery to identify crop water stress over extensive areas can help optimize irrigation.

Best Practices & Management Strategies For Water Management

Good agricultural water management combines monitoring data with strategic practices to achieve efficiency:

Precision Irrigation

Many farmers are doing better with advanced irrigation management that applies water when and where it’s needed in real time:

• Variable Rate Irrigation: Varies the amount of water applied to fields according to soil type, topography, and even crop needs.
• Deficit Irrigation: Deliberately provides less water than is optimal during drought-resilient growth phases to enhance water productivity.
• Irrigation Scheduling: Install evapotranspiration data and soil moisture measurement activities to define the best irrigation time and quantity according to the condition of crops.

Conservation Practices

Such field-level practices serve to optimize the use of available water:

• Mulching: Using organic or synthetic materials on the soil surface to reduce evaporation and competition with weeds for available water.
• Conservation Tillage: Minimizing soil disturbance preserves soil structure and water-bearing capacity, reducing the potential for evaporation.
• Cover cropping: Planting cover crops (that is, non-monetary crops planted during periods that are not growing seasons of the cash crops) improves the soil structure and decreases erosion and increases water infiltration rates and retention. This method reduces runoff and promotes infiltration since it slows water movement across the landscape.

Soil Health Management

But healthy soils naturally hold more water:

• Organic Matter Management: Water-holding capacity can be vastly improved by increasing soil organic matter content, where each 1% increase in organic matter will hold an estimated 20,000 gallons of water per acre.

• Severe Compaction: Avoiding and fixing soil compaction helps water get into the soil and plant roots to reach soil moisture.

Water Quality Protection & Environmental Considerations

Water resources on the farms are just the first part; agricultural water management is an issue of protection of surrounding water bodies, too:

Mitigating Agricultural Runoff

• Buffer Strips: Areas of vegetation along waterways that intercept sediment, nutrients and chemicals found in runoff prior to entering water bodies.

• Tailwater Recovery Systems: Collect irrigation runoff to treat and cycle back for reuse instead of going into natural water systems.
• Precision Nutrient Management: Nutrients application must be done at the right amount, right time, and right place, as it reduces the chances of nutrient leaching and runoff.

Protecting Water Sources

• Wellhead Protection: The protection of the area surrounding drinking water wells from being contaminated from the qualities of chemicals and waste.
• Permanent Riparian Zones: This involves keeping a buffer of healthy vegetation along bodies of water that enacts natural filtration to protect waterways from runoff while also preventing erosion.
• Wetland Conservation: Conserving natural wetlands contributes to filtering agricultural runoff and aids in groundwater recharge.

Future Directions Of Water Management In Agriculture

With the growing scarcity and value of water, a number of developing trends are paving the way for the future of agricultural water management:

Climate-Resilient Water Systems

Development and adoption of crops that produce well with less water.

Water Storage Infrastructure: Increasing on-farm capacity to capture precipitation during wet periods for use during dry periods.

• Diversified Water Portfolios: balanced use of different water sources for improved dependability and resiliency.

Data-Driven Decision Support

• Machine and Deep Learning: Sophisticated algorithms which combine various data feeds to make irrigation decisions optimal.
• Blockchain for Water Rights: Using emerging technologies to improve water allocations and trading efficiently and transparently.

Internet of Things (IoT) Networks 

Connected sensors provide comprehensive, accurate, real-time monitoring across entire watersheds and farming regions.

Conclusion

Cutting-edge monitoring technology offers valuable information about water amount and quality, allowing precision management that would have been unimaginable just a generation ago. By persistently tracking important parameters such as soil moisture, flow rates, conductivity, pH, and nutrients, the agricultural production industries can time precisely the right amount of water at exactly the right moment and identify and rectify quality issues prior to impacting crop yields.

Understanding these water uses in the agricultural sector is the basis for strategies that effectively manage water and balance productivity with sustainability. Whether you are a producer aiming to optimize water productivity, a conservationist aiming to guard natural resources, or a technology provider that creates new-generation solutions, understanding applications of water in agribusiness is the insight that drives impact.
If you would like to learn about the invaluable agriculture measuring tools we have to offer, do not hesitate to contact the world-class team at Atlas Scientific.