Episode 71: Water & Agriculture with Ashwin Madgavkar (Ceres Imaging)

Episode Intro Notes

Outline

• Why is water important to agriculture?

• How much water is used in agriculture and what types of agriculture require the most water?

• Where in the world is the most water used for agriculture and what are the most water-stressed agricultural areas?

• What are innovations and approaches that can help reduce water used and needed in agriculture?

• Ashwin Madgavkar, Founder, Ceres Imaging

why is water important to agriculture?

• Put simply, water is a critical input for essentially all agricultural production. You want food? You need water.

• We’ll get into later the embedded water footprint of different types of food.

• Farmers get the water they need in different ways–rain, groundwater, surface water, and irrigation.

• Irrigation is key to food production. Just 20% of total available agricultural land is irrigated, but that land accounts for 40% of food production.

How much water is used in agriculture and what types of agriculture require the most water?

• Irrigated agriculture is the largest user of water globally. Currently, agriculture accounts (on average) for 70 percent of all freshwater withdrawals globally.

• So how much water is that 70% of freshwater withdrawal globally put toward agriculture? Well each year that’s over 2 quadrillion gallons of water, enough to cover the entire United States in 2 feet of water.

• Sadly, a good chunk of that water goes into the environment rather than directly helping the targeted plant grow.

• World Wildlife Fund says around 60% of the water used in agriculture is wasted due to leaky irrigation systems, evaporation, inefficient application methods, as well as the cultivation of crops that are too thirsty for the environment in which they are grown. 

• For more on issues with leaky water infrastructure, check out episode #21 on water infrastructure.

• Importantly, while agriculture depends on water, it’s also a major source of water pollution. Agricultural fertilizer run-off, pesticide use, and livestock effluents all contribute to the pollution of waterways and groundwater.

• Demand for water in agriculture and for many other uses is expected to increase considerably as our global population goes from just over 8 billion today to over 10 billion by 2050.

• Combined with the increased consumption of calories and more complex foods, which accompanies income growth in the developing world, it is estimated that agricultural production will need to expand by approximately 70% by 2050.

• Let’s talk about the water necessary for certain types of foods. We wanted to get this info all from one source so it’s more apples-to-apples numbers, and we found watercalculator.org to be a good source. The water footprints we note below are all based on a four ounce serving.

• Livestock like cows and pigs are a big one. Beef takes 463 gallons (1,752 liters) per serving. Pork and bacon is 180 gallons (681 liters) per serving. Chicken and turkey are both 130 gallons (492 liters) per serving.

• A big part of the footprint for these animals is not giving water directly to the animals but rather the water used to grow the crops to feed the animals. In the United States, a third of all consumed water goes to irrigate crops not for human consumption, but those used to feed beef and dairy cattle. In the Colorado River basin, it’s over 50 percent. We’ll talk more about the Colorado River basin later on in this intro.

• Then there’s making non-animal products and growing produce.

• Chocolate is listed on the water calculator as the worst. 516 gallons (1,953 liters) per serving. Second is almonds at 483 gallons (1,828 liters) per serving. Then, for context, we’ll note that third on the overall list was the beef footprint we discussed.

• Some other notables:

• Cashews at 427 gallons (1,616 liters) per serving.

• Lots of nuts at the top of the list

• Quinoa is 135 gallons (511 liters) per serving.

• Tofu is 76 gallons (287 liters) per serving

• Wheat flour is 55 gallons (208 liters) per serving.

• And then on the watercalculator.org website there was a four-way tie for the most water efficient food at 6 gallons (22 liters) per serving between carrots, celery, tomatoes, and turnips.

1. And to conclude, let’s zoom out and talk about water generally to make the food to feed a person. The UN Food and Agriculture Organization estimates that between 528 and 1,321 gallons (2,000 and 5,000 liters) of water are needed to produce a person’s daily food.

Where in the world is the most water used for agriculture and what are the most water-stressed agricultural areas?

• We found an Our World in Data page last updated in 2018 with some good information from the UN Food and Agriculture Organization's Aquastat database that has by country the agricultural water use withdrawals and the percentage of freshwater withdrawals used for agriculture.

• India was listed as the world’s largest agricultural water consumer at nearly 700 billion cubic meters per year. China is the world’s second largest user at approximately 385 billion cubic meters.

• Now let’s talk percentage of freshwater withdrawals used for agriculture.

• The average agricultural water use for low-income countries is 90 percent; 79 percent for middle income and only 41 percent at high incomes.

• There are a number of countries across South Asia, Africa, and Latin America that use more than 90 percent of water withdrawals for agriculture. The highest in 2019 according to the UN FAQ Aquastat data was Somalia at 99.5 percent. More on the dire state of affairs in Somalia in a minute.

• Countries in the global north tend to use a much lower share of water for agriculture; Germany and the Netherlands use less than one percent. 

• Climate change is projected to increase the fluctuations in precipitation and surface water supplies, reduce snow packs and glaciers, and affect crop’s water requirements. Droughts and extreme weather events are expected to become more frequent as well.

• An OECD assessment of future water risk hotspots projects that without further action, Northeast China, Northwest India, and the Southwest United States will be among the most severely affected regions, with domestic and global repercussions.

• Let’s zoom in on a couple different countries.

• We mentioned Somalia earlier and like all of East Africa, it continues to face a severe drought. With Somalia on track for a fifth failed rainy season, there have been no crops in the fields for more than two years. During these repeated droughts, people who can no longer live off the land often end up on the outskirts of Baidoa, capital of Somalia’s South West state. By July 2022 there were 498 verified camps for the displaced, with dozens more informal settlements. The World Health Organization says every single person in Somalia is facing hunger on a scale not seen since the famine in 2011, which killed more than a quarter million people, half of them children.

• For those wanting to help in this situation, there are charities on the ground. One fund is the Somalia Humanitarian Fund. It’s one of the UN's country-based pooled funds. Contributions are collected into a single, unearmarked fund and managed locally under UN leadership.

• Our podcast is going to try another matching donation challenge for our Definers of up to $250. If you’d like to donate, go to crisisrelief.un.org/somalia and then email your receipt to hosts@sustainabilitydefined.com to get the match.

• Friendly reminder of our other charitable match for our listeners for the Uproot Project, which supports journalists of color covering the environment. We announced this in our 2022 Holiday Hodge Podge episode. Same deal, go to uprootproject.org, send your receipt to hosts@sustainabilitydefined.com, and we’ll match it if we haven’t hit our max.

• Nex, let’s also look at India and its 600 million farmers.

• Extreme weather events like heatwaves and unseasonal rains occurred on 88% of the days in the first nine months of 2022, affecting 1.8 million hectares of India’s crop area. Because over 50% of India’s net cultivated area is rainfed and accounts for nearly 40% of the total food production, this crisis also impacts consumers and India’s economy. Unfortunately, these sort of extreme weather events are going to become more common as climate change worsens. 

• Groundwater is also important to Indian farmers and that’s being depleted. Many of India’s farmers primarily irrigate their crops with wells that draw water from within the ground. The result is that a third of the country’s aquifers are being pumped “much faster” than they can replenish.

• There have been frequent protests by farmers and sadly, one recent estimate says nearly 30 Indian farmers commit suicide each day, typically due to overwhelming debt and other stressors.

• And last, let’s look at the United States, particularly the Colorado River, which is at historically low levels due to the ongoing 20 year megadrought in the Southwestern U.S. The reservoirs Lake Mead and Lake Powell are at record lows. Federal officials are demanding historic cuts in water use next year and this means some farms won’t be able to operate at all or won’t water some of their fields. Consider the hundreds of farms in Imperial County on the southern tip of California. These farms draw more water from the Colorado River than all of Arizona and Nevada combined.

• So how to solve this? One draft plan has farmers being paid to use less water. About $1,500 per acre – almost $1.4 billion in total – in exchange for cutting water use by roughly 20 percent on almost a million acres of farmland. This is an ongoing crisis. The reality is the Colorado River doesn’t have the water to support all the farms that generate billions of dollars in revenue and the crops relied on in the United States and the world.

• And to tie the water stress globally to what’s going on in the Southwest U.S., in some cases, it’s entities from abroad that own the farms. After Saudi Arabia finalized a ban on growing thirsty crops like alfalfa and hay to feed livestock and cattle because the Middle East is running out of water, Saudi companies bought farms in Arizona to grow crops for their cattle. There are laws in Arizona against exporting water but not against exporting goods that consume a lot of water. In our next section, we’ll see why the water policies in Arizona made this an attractive investment even with the lack of water in the state.

What are innovations and approaches that can help reduce water used and needed in agriculture?

• That was a lot of doom and gloom up to now but in this section we want to dive into the future and solutions. We’re going to talk about policy, infrastructure, technology, and farming techniques.

• Policy

• One policy approach to rein in inefficient water use in agriculture could be simply putting a price on water. Water often remains hidden in the economic valuation of agricultural assets since oftentimes farmers do not pay for the costs associated with withdrawal and delivery. Water markets and water trading can be found in Australia, the United States, Mexico, Chile, China, Spain, and South Africa. However, these are more exceptions than the rule because in most of the world there are no tradable water rights. Rather, water is either tied to land’s property rights or treated as a public good, “res nullius” (i.e., an open access resource).

• Another policy approach is limiting how much can be extracted from the surface water and groundwater so that we can track water use and not use more than local resources can provide.

• Consider Arizona and groundwater. In the 80% of the state outside of its so-called “active management areas,” there’s no restrictions on how much groundwater can be pumped and no way to monitor it.

• Infrastructure

• One infrastructure improvement that will conserve water in agriculture is making sure the water isn’t lost as it's being transported to the farm. According to the U.S. Department of Agriculture (USDA), off-farm sources account for 40 percent of total water applied to U.S. irrigated cropland. USDA says irrigation water delivery organizations in 2019 released nearly 22 trillion gallons of water. About 16% of that water was lost to evaporation or seepage during storage or transport. Lining water canals with quasi-impermeable materials such as concrete or plastic membranes can reduce conveyance losses, as less water is lost to seepage. However, a large proportion (about 72 percent) of the main and lateral canals owned by irrigation organizations remain unlined, mainly because of cost, or they believe the lost water will recharge aquifers or be minimal due to soils and geology.  

• We could also create more infrastructure for rainwater harvesting. Rainwater harvesting is the accumulation and storage of rainwater runoff for reuse before it reaches the aquifer. The water could be collected via a variety of means from dwelling houses and farm sheds, road surfaces, concrete surfaces, and plastic surfaces including greenhouse coverings. It can help reduce dependence on and depletion of groundwater.

• In the U.S., you can’t legally harvest as much rainwater as you want in all the states. Some states, particularly in the west like Colorado have restrictions, but no states outlaw it according to a 2022 review of the topic we’ll link to on our site. In fact, some states like Rhode Island, Texas, and Virginia encourage residents to collect rainwater by offering a tax credit or exemption for equipment purchased for rainwater harvesting.

• Technology

• 85% of all irrigation is still done by releasing vast quantities of water across the surface of a field, pretty much the same way it was handled 4,000 years ago in Mesopotamia. With flood irrigation, as much as 70% of the water is unnecessary, and overwatered crops can fail to reach their full potential. Today, there are hundreds of drip irrigation companies, but the technology is being applied to less than 5% of irrigated acres globally. Why such a small percentage? Largely due to cost. For one, it takes energy to pump the water through hundreds of feet of pipe. Also, the dripper lines can get clogged with the silt found in natural water so it must be filtered, adding another expense. The whole setup amounts to at least $2,000 an acre, plus energy bills. For lower-value crops such as cotton or alfalfa, drip irrigation simply doesn’t pay.

• However, we read about some innovative new companies looking to dramatically lower that cost. One is the Israeli start-up N-Drip, which has an installation cost of $400 an acre. A lot of the cost savings come from using gravity to provide the required pressure to force the water through the pipes. N-Drip has raised $25 million in funding, and its system is being used by hundreds of farmers for 4,000 acres’ worth of crops, ranging from cotton to potatoes to soybeans. But of course there’s a long way to go to converting the Earth’s 600 million flood-irrigated acres.

• But even with drip irrigation, a farmer may be watering too much or too little. New technology has come online to help farmers with “irrigation scheduling,” deciding how long and how often to irrigate. Smart irrigation technologies make use of local weather stations that measure air temperature, humidity, wind speed, and rainfall; soil probes that measure soil moisture depth, temperature, and salinity; and plant moisture sensing devices that measure the water pressure in plant cells. Increasingly, software paired with these technologies allows growers to easily access real-time data on field conditions, receive alerts through email and text messages, and automate or control their irrigation systems remotely. 

• Farming techniques

• Farmers could explore combinations of plants (i.e., crop diversity) so that they can grow more plants with the same amount of water.

• One recent study found that cowpea grown with millet can produce the same millet yield as millet alone. This means farmers could get additional protein-rich cowpea with the same quantity of water.

• Another technique that could be used to save water is “deficit irrigation,” which is the practice of watering plants less frequently but in a targeted manner. It can force the plant to dig their root systems deeper and be less dependent on watering.

• Farmers can also plant cover crops like grasses or legumes in between growing the cash crops. Cover crops improve the health of soils by keeping the soil covered, cooling the surface, and reducing water lost to evaporation. Healthy soils mean more water is in the soil for plants to access, meaning less watering is needed.

• Certainly one way to have healthy soils is no till agriculture, which is where the soil is not plowed, and this practice can help conserve water in a variety of ways. One way is soil pores serve as the conduits for water, and with no till, there is less clogging of the pores, which means water can flow even more freely.

• We talked a lot about cover crops and other forms of regenerative agriculture in our episode #23 on agroecology. 

• For those who like to consume their information movie documentary style, consider checking out on Netflix the documentary Kiss the Ground, which has science experts and celebrity activists unpack the ways in which the earth's soil may be the key to combating climate change and preserving the planet.

Ashwin Madgavkar, Founder, Ceres Imaging

• Ashwin got his undergraduate degree in electrical engineering from University of Texas-Austin, and he got his MBA from Stanford.

• While a graduate student at Stanford, Ashwin was inspired to launch Ceres Imaging by the plight of California growers navigating a severe drought and by emerging technology in spectral imagery.

• Ceres Imaging has its headquarters in Oakland, California, and it serves growers in Australia, South America, and the United States. It delivers precision agriculture solutions that help growers detect acute issues, track and measure progress, and improve farm performance.