Water and Food

In much of the world food prices are rising. The effects of the current price spikes have not been significant in the United States where food represents about 10% of the income of a typical family and where the volatility in food and energy are accepted or at least tolerated. In the United States processing and advertising costs of foods often outweigh the cost of food ingredients themselves.

Food prices are being driven up in part by an increase in oil prices, affecting both fuel and fertilizer costs. But the primary cause is water. The recent droughts and flooding have both impacted food production. Russia has been hit with the worst drought in a half century. Australia has suffered years of drought only to be hit by torrential flooding so that the lack of water has been replaced by too much water. India’s falling water table and water shortages have been well documented in the world news. Even U.S. grain forecasts have been reduced due to adverse weather.

In countries where most residents purchase only basic foodstuffs and where food costs require a much larger percentage of household income, the cost of food has effectively skyrocketed. When food represents 50% of household income, a 10% increase cannot be absorbed. The outcry in India over the price of onions recently illustrated this. India’s food production regions are reportedly sitting atop groundwater aquifers that are being depleted. Irrigation accounts for 84% of India’s total water use. The population continues to grow, industrial demand for water grows and the demand for more water intensive food is growing. Generally, higher value crops such as sugar and vegetables are more water-intensive than cereals, and meat and dairy are even more water-intensive. So as populations move up the economic ladder beyond subsistence the demand for irrigation water explodes.

Overall, approximately 60% of all the world's freshwater withdrawals go to irrigation. Large-scale farming could not provide food for the world's large populations without the irrigation of crop fields by water from rivers, lakes, reservoirs, and ground water wells. Without irrigation, crops could never be grown in the arid and semi-arid lands of California, the Middle East, or India where irrigation consumes a much larger share of fresh water.

The majority of irrigated acres in the United States is in the west were where annual precipitation is less than 20 inches and is insufficient to support crops without supplemental water. In the western United States water used for irrigation exceeds 75% of the water supply. The system of water rights that developed in the west assured for generations the allocation of water to agriculture. The water rights system as conceived and administered in the western states was not designed to conserve water. It was developed in a time when population was still sparse, water supplies were believed to be plentiful and development and growth were to be encouraged. The system was designed to protect the water and work necessary to build farms in the west. This management scheme has resulted in non sustainable use of groundwater and unsustainable agricultural practices.

When agricultural land is irrigated, the water balance in nature is altered. Water is withdrawn from a river, spring, or groundwater and added to agricultural fields. The environmental impact of an irrigation system is dependent on the nature of the water source, the quality of water, the method of delivery and the local geology and climate. Withdrawing ground water beyond the recharge rate may cause the land to subside as happened in the Central Valley of California. In many parts of the world where water is often plentiful slash and burn agriculture is practiced and the land cultivated until it is exhausted then abandoned, more forest cut down and the climate impacted by the massive loss of trees. Irrigation of lands can destroy them.

Aquifers and the land may become saline. All water contains dissolved salts that attached to the water molecules as it washed over the land or percolated in the ground. Rain also contains some salts. The salts are generally at very low concentrations in “fresh” water’ however, evaporation of water from dry earth leaves much of the salts behind. Over time the salts concentrate. This problem has become acute in the Central Valley of California, in China’s North Plain, in Soviet Central Asia (the –istans), parts of the Middle East and the Colorado River Basin. These are all semi-arid areas where irrigation is the basis of agriculture that has used flooded irrigation for generations. Land is being irrigated before planting to reduce the salt levels. At least 20% of all irrigated lands are salt-affected, with some estimates being as high as 50%.

To address these problems, more controlled types of irrigation have been developed and more salt tolerant crops need to be exploited. Micro-irrigation also known as drip irrigation has gained attention during recent years because of its potential to increase yields and decrease water, fertilizer, and labor requirements if managed properly. Drip irrigation systems can apply water and fertilizer directly to individual plants or trees, reducing the wetted area by wetting only a fraction of the soil surface; water is applied directly to the root zone.

In drip irrigation, water is run through pipes (with holes in them) either buried or lying slightly above the ground next to the crops. Water slowly drips onto the crop roots and stems. Unlike spray irrigation, very little is lost to evaporation reducing water waste. Subsurface drip irrigation is the slow frequent application of water below the surface to the root area of the pants. The goal is to maintain constant moisture content in the soil at the optimal plant growth level. This requires monitoring soil moisture and weather instead of a set irrigation schedule and in this way reduce net water use by 30%.

The costs involved in drip irrigation can be substantial, not just the $800-$2,000 for the tubing, filters and pumps, but also the irrigation infrastructure that would allow controlled constant delivery of filtered water. On demand water availability for irrigation may be an insurmountable hurdle within the current water allocation system. In addition, a University of California study concluded that a salt balance must be maintained in the root zone, irrigation without improved management practices cannot be sustained in the San Joaquin Valley. In addition, sensible choices will have to be made about water allocation, crop choices, and water pricing. Our political systems and human nature have not excelled in the past at sensible.

The Error in the Allocation to Agriculture Under the Virginia TMDL

The most recent meeting of the Potomac Watershed Roundtable was in Warrenton, VA at Lord Fairfax Community College and had a series of speakers on the Chesapeake Bay strict pollution diet, the Total Maximum Daily Load (TMDL) mandated by the EPA to the six Chesapeake Bay Watershed states and the District of the Columbia. The TMDL addresses only pollution from excess nitrogen, phosphorus and sediment. No action has been taken or at this time is intended on other pollutants that might be present in the Chesapeake Bay and its tributaries. Part of the meeting was devoted to educating the audience on the Chesapeake Bay Model.

The TMDLs were created by a series of models of the Chesapeake Bay Watershed that include various land use models, water quality models and watershed models. These computer models are mathematical representations of the real world that estimate environmental events and conditions. The models are at best imperfect, but they are nonetheless the best tool available to view the 64,000 square miles of the watershed. The Chesapeake Bay and its watershed are so large and complex, that scientists and regulators rely on computer models for critical information about the ecosystem’s characteristics and the impact of various environmental actions to reduce pollution.

Mike Rolband of Wetland Studies and Solutions, Inc. had some fun with what is apparently one of the large mistakes in the model that is expected to have a correction released in the near future. His professional interest is in managing impervious and pervious surface run off. His consulting firm looked at the underlying data used to create the Land Use estimates. Land Use model estimates the types and amounts of pollution that run off a particular land use are based on comprehensive reviews of the latest scientific literature there is limited measurement here for many of the land uses, but the responsible land use is assigned a numeric blame. Using EPA published data Wetland Studies and Solutions was participant in pointing out to the EPA that they had massively underestimated the impervious and pervious surface areas in the Urban Areas in Virginia (and I assume other areas).

It seems that the most recent version of the model had used approximately 675,917 acres for the impervious surface data and 1,885,915 acres for the pervious surface data. A review of the EPA’s own data found that there were 1,569,377 impervious acres and 3,442,346 pervious acres in the urban areas in the Virginia segments of the model. These include all the paved and landscaped areas of suburbia. Between the 1990 census and the 2010 census the population of Virginia grew from 6.2 million people to 8.0 million people. The bulk of that growth took place in the urban and suburban centers of the Chesapeake Bay watershed.

Now here is where it gets interesting. Pollutions loads for nitrogen, phosphorus and sediment in the urban areas are calculated using a constant pounds/acre/year for impervious acres as a fixed input, and the pervious load is based on total fertilizer sales data. The bottom line is that the EPA has confirmed that they will not change the loading rate because they have high confidence in the loading rate for the impervious surfaces and the total fertilizer sales are reported and tracked data and is a hard number. Thus the total current oad for the urban areas will increase by 2,238,449 pounds of nitrogen per year, 636,097 pounds of phosphorus/year and 137,680 pounds of sediment/per year. However, the total watershed loads for the overall model will remain the same. So, while the urban area loads will increase, other area(s) loads will have to decrease.

Mike Rolband has pointed out that the agricultural sector will probably have their load reduced. The waste water treatment plants numbers are based on constant sampling necessary for their permits so their overall total contaminant load will not change. The forest lands number is also believed to be a “good” number, so that leaves the agricultural sector and in the case of total nitrogen, also septic. Over 2.2 million pounds a year is a lot of nitrogen it represents of the total load attributed to agriculture. The farm segment has been protesting loudly that they are not being given proper credit for implementation of best management practices and that surface waters are already degraded when they reach their farms.

It seems that the American Farm Bureau Federation who have recently filed suit against the EPA claiming the models are flawed is right. The smug assumption that farmers are the bad guys by the new generation of environmentalists is to an extent wrong. Man is the animal contributing the most nitrogen to the Chesapeake Bay in the form of wastewater treatment plant permitted waste, septic and urban/ suburban runoff. The Chesapeake Bay Foundation owes the American Farm Bureau Federation an apology for their recent quote in the Washington Post.

The Revised Watershed Implementation Plan and Farmers

For agricultural operations the revised WIP will require the implementation of resource management plans on most agricultural acres which may include: 35 foot grass or forest buffers between cropland and perennial surface waters; stream exclusion of livestock over time; and implementation of nutrient management plans. The Commonwealth intends to provide cost-share funding to achieve implementation of these best practices through the soil and water conservation districts. The WIP calls for farms to implement "resource management plans" to reduce pollution but does not mandate what those plans should include and requires them only if adequate funding is available through the cost share programs. These programs are cost share programs and do require financial participation of the farmers. The Chesapeake Bay Foundation objects to the seemingly soft requirement of this provision stating that 30% of the nutrient and sediment pollution is from agriculture.

I was thinking about justice and regulations as I was trying to straighten out a problem at my Bank. I found myself waiting interminably for the branch manager with another customer with his own problem. We had both driven the 16 miles from our corner of Prince William County to wait at Bank of America on Route 50 and to face seemingly insurmountable regulations. While we were waiting, my neighbor, a fourth generation cow farmer, told me about his concerns with the WIP. His cattle are sustainably and locally raised and for the most part are pasture raised on grass; however, he admitted that the cows are watered by the streams that come together in our area to feed Bull Run. His concern was if he needs to build stream exclusions, and bridges for the cows to move from one pasture to another then create watering systems for the cows in each pasture that the cost would put him out of business even with cost sharing. He also voiced concerns that nutrient contamination coming from upstream sources would prevent him from being able to achieve the targets of the Chesapeake Bay TMDL. Since he had not read the revised WIP many of these concerns may have not been well founded or researched, but certainly the WIP will have a profound impact on his business and the business of all farmers in the Chesapeake Bay Watershed.

According to the National Association of Conservation Districts, NACD, there are 4.3 million acres of farmland within the Chesapeake Bay Watershed that will be impacted by the U.S. Environmental Protection Agency’s new Total Maximum Daily Load, TMDL for the bay. A USDA draft report reportedly shows that farmers and ranchers are making good progress in the Bay, but that is not enough to meet the stricter demands of the TMDL. Of the actively-cropped 4.3 million acres, farmers are actively implementing erosion control and nutrient management practices on more than 4.1 million acres. The NACD states that these actions have reduced sediment pollution on rivers and streams within the Chesapeake Bay watershed 64%, cut nitrogen pollution 36% and reduced phosphorus pollution 43%. Nonetheless, the Chesapeake Bay foundation states that 30% of the nutrient pollution in the Chesapeake Bay Watershed is from agriculture operations and is pressing strongly for tighter regulations and enforcement against agricultural operations. .

I had no answer as to whether sustainable, humane, local agriculture should be encouraged, or if the world is better with a few high intensity concentrated animal feed lots that have a combined smaller land footprint and are not in sensitive watersheds. Though, I am not at all certain that there are any locations not in some sensitive watershed. In the west (home of many agri-industrial operations) water diversions are having severe impact on the environment. The agricultures economy is manipulated by farm subsidies that distort the market and agricultural practices. To pay for the increase costs of complying with the higher costs of sustainable agriculture, instituting nutrient management and best practices and enforcement of those steps the cost of food will have to rise either directly or indirectly. I only know I would prefer to continue to buy my meat locally from an operation where I can see the cows are grass fed and pastured. Then there are the hobby farm operations, lots zoned to allow horses and the current push for a zoning to allow backyard chickens in the much of Prince William County. It is impossible reconcile the requirements necessary to comply with the Chesapeake Bay TMDL with the personal freedom, small scale local food and population growth.

Agriculture a Source of Pollution and Environmental Impact

Non-point source pollution is cumulative in nature. While any single contributor of non-point source contamination may be insignificant, the cumulative effect of many such sources is measurable and leads to significant pollution of ground and/or surface waters. Surface and groundwaters are interrelated. Groundwater is surface water (lakes, rivers, streams, or overland flow from precipitation) that has percolated into and then through the ground to an aquifer. Groundwater may move back into surface water bodies through seepage, springs, or base flow into a river or lake depending on the geology of an area. Contaminated groundwater can move into uncontaminated aquifers or return to surface water, depending on the geology. Section 319 of the Federal Clean Water Act mandates development of programs for control and reduction of non-point source pollution of both surface and ground water.

Non-point source contamination comes from run off both agricultural and urban as well as other small sources such as septic and AOSS. Agriculture is reported to be one or the main non-point sources of water pollution and in studies done in the Chesapeake Bay Watershed and Sacramento River Delta and other locations the contamination from agriculture runoff has been the major source of contamination. Pesticide runoff is a large contributor of known pollutants to the watersheds and may be a significant contributor of endocrine disruptors to the freshwater supply. Both rain feed and irrigated agriculture are sources of contamination of fresh water. In April of 2009 the US EPA issued the Final List of Initial Pesticide Active Ingredients and Pesticide Inert Ingredients to be Screened Under the Federal Food, Drug, and Cosmetic Act as potential endocrine disruptors. These pesticides need to be further investigated and our use of pesticides reexamined and rethought.

In rain fed agricultural land, the precipitation washes agricultural chemicals (pesticides and herbicides) along with soil sediment to surface water. In addition, irrigation of the fields can increase the run off. Other sources of non-point souce contamination are confined animal feed lots, grazing, plowing, pesticide spraying , fertilizing, planting and harvesting a crop which can all contribute to run off of contaminants and sediment. The National Water Quality Inventory Report to Congress was intended to identify widespread water quality problems of national significance. This has served as a proxy for the quality of the waters of the nation despite a non systematic approach to identifying water quality by the states and significant limitations to the substances tested for. Many states target their limited monitoring resources to waters they suspect are impaired and, therefore, assess only a small percentage of their waters. These may not reflect conditions in state waters as a whole and tend to reflect areas of concern in the “water community.” The US-EPA in its last report to Congress identified agriculture as the leading cause of water quality impairment of rivers and lakes in the United States. Agriculture is also cited as a leading cause of groundwater pollution in the United States.

There are other significant environmental impacts from agriculture. When agricultural land is irrigated, the water balance in nature is altered. Water is withdrawn from a river, spring, or groundwater and added to agricultural fields. The environmental impact of an irrigation system is dependent on the nature of the water source, the quality of water, the method of delivery and the local geology and climate. Withdrawing ground water beyond the recharge rate may cause the land to subside as happened in the Central Valley of California. Aquifers may become saline. All water contains dissolved salts that attached to the water molecules as it washed over the land or percolated in the ground. Rain also contains some salts. The salts are generally at very low concentrations in “fresh” water’ however, evaporation of water from dry earth leaves much of the salts behind. Over time the salts concentrate. The problem is acute in the Central Valley of California, in China’s North Plain, in Soviet Central Asia (the –istans), parts of the Middle East and the Colorado River Basin. These are all semi-arid areas where irrigation is the basis of agriculture.

Withdrawing both groundwater and surface water can dramatically change the natural hydrology of rivers and water streams, water temperature, and can impact the aquatic ecosystem associated with the surface water. The San Joaquin River in California has been dewatered as has been Owens Lake. The Colorado River runs dry before it reaches the Ocean most years as does the Yellow River in China. The riparian ecosystems and delta estuaries associated with these areas no longer receive fresh water recharge and have been destroyed.

However, irrigation has vastly improved crop yields in many semi-arid climates. As population grows, and the demand for food increases irrigation is unlikely to be discontinued. Methods and control of irrigation can determine the extent of the environmental impact from the irrigation. Improved field irrigation practices are critical to limiting the impact. It is reported that irrigated agricultural land is two and a half times more productive than rain fed agricultural land and the limits of irrigation really are the fresh water resources, the capital costs and the saline buildup over time in the farm land and aquifers. To feed the populations of the earth and protect the earth mankind needs to utilize intelligent and environmentally balanced farming practices employed .