Policy Issues in Developing Countries

The primary policy questions in developing countries are more challenging, in part, because financial resources are limited and there are many competing demands on public funds. In addition, much of the wastewater irrigation takes place in decentralized, informal settings in which individual farmers gain access to wastewater very simply by diverting polluted water from a stream or ditch. Property rights to the water are not defined, and there is no communal agency or water user association that coordinates irrigation activities. Millions of individual farmers will be very reluctant to stop diverting polluted water for use in irrigation, given that their livelihoods currently depend on the sale of irrigated farm produce.

Public officials in developing countries must address the following question: How do we minimize the risks to farmers and consumers, while not destroying or severely diminishing the livelihoods of those farmers who currently irrigate with wastewater? This is not an easy question to answer. Public officials will be mindful of the benefits that farmers provide by diverting and using polluted water for irrigation. If not for that activity, larger volumes of wastewater would continue flowing downstream in

TABLE 2 Average Nutrient Availability in Human Excreta per Person, per Year

Nutrient

Amount of Nutrient Available (kgs)

Amount of Nutrient Required to Produce 250 kg of Cereal (kgs)

In Urine (500 liters)

In Feces (50 liters)

Sum

Nitrogen

4.0

0.5

4.5

5.6

Phosphorus

0.4

0.2

0.6

0.7

Potassium

0.9

0.3

1.5

1.2

many watercourses, creating greater risk for downstream residents and causing environmental harm over a larger area. Farmers who irrigate with wastewater generate one set of risks for their families and consumers while reducing another set of risks to residents downstream.

Public officials also will note that some of the pollutants in municipal wastewater (such as nitrogen, phosphorous, and potassium) are plant nutrients. In areas where inorganic fertilizer is costly and difficult for small-scale farmers to obtain, those nutrients have substantial agronomic value. The nutrients contained in the average amount of urine and feces generated by one person each year are sufficient to produce enough grain to sustain that person. Urine is a particularly good source of nitrogen, phosphorus, and potassium (Table 2). Efforts to collect and transport urine directly to farms, rather than discharging it to waterways, would allow farmers to manage their nutrient applications with greater care and accuracy.

In summary, farmers generate both private and public benefits when they divert polluted water from streams and ditches to irrigate crops in urban areas. The nutrient content of wastewater is sufficient to increase crop yields, provided that farmers do not apply excessive amounts of some nutrients, such as nitrogenJ* 1 2 3 4-43! Public officials in developing countries must determine how to sustain these beneficial aspects of wastewater irrigation and the livelihoods of farm families, while minimizing risks to those same families and the consumers of their produce.

Policy Options Include Treatment and Non-Treatment Alternatives

The policy options available to public officials for reducing the risks associated with wastewater irrigation in developing countries, while sustaining livelihood benefits, might be placed into four categories:

  • 1. Improve and extend centralized wastewater treatment
  • 2. Improve and extend decentralized wastewater treatment
  • 3. Regulate (with enforcement) the use of untreated wastewater in agriculture
  • 4. Complement existing wastewater use patterns with risk reduction interventions to protect farm families, communities, and consumers

The first category is likely the most costly and the least likely to be implemented along a reasonable timeline. There might be affordable opportunities in some settings within developing countries, in which new, large-scale wastewater treatment plants can be constructed to improve the quality of water available for agriculture. Yet it seems that if such opportunities were affordable, if they compared favorably with alternative public investments, and if an affordable source of finance were available, then such efforts would already be underway. It is difficult to imagine that the pace of investments in large, centralized wastewater treatment plants will be sufficient to improve water quality for many of the farmers who currently use wastewater for irrigation in developing countries.

The second category includes options that should be more affordable than building large, centralized wastewater treatment plants. The goal within this category is to identify opportunities for enhancing irrigation water quality at an appropriate scale and within a meaningful distance from the point of wastewater use. Small-scale wastewater treatment plants might be designed with the expressed purpose of making higher-quality water available for irrigation. The construction costs and operating criteria for such plants might be different—and less expensive—than those pertaining to centralized wastewater treatment plants that discharge water intended for uses outside agriculture.1441 For example, it is important to remove solids, salts, and pathogens from water intended for use in irrigation, but farmers can accommodate higher nutrient levels than wastewater users in municipal and industrial settings.

The third option likely will be challenging in many developing-country settings, given the decentralized, informal nature of wastewater use and the strong dependency of farm households on wastewater. Regulations will be politically unpopular, and enforcement will be difficult to achieve. In Syria, for example, the government disallows the irrigation of vegetables with wastewater, but compliance with the restriction is not complete. Syrian officials resort to destroying vegetable crops irrigated with waste- water when they find such situations. As a result, less than 7% of the area irrigated with wastewater near the city of Aleppo is in vegetable production.127! '[he opportunity costs involved in planting and cultivating crops, only to have them destroyed by the government, can be substantial for farm households with limited sources of income.

The financial burden of treating wastewater in developing countries and the challenge of regulating wastewater use by farmers will remain substantial for the foreseeable future. Hence, many farmers will continue using wastewater, and their workers and families will remain at risk of infection while applying irrigation water. Consumers will remain susceptible to sickness caused by handling and consuming the irrigated produce. Given this near-term outlook, public agencies in developing countries should seek opportunities to reduce the risks of infection and sickness by intervening at selected stages of the process, which includes wastewater generation, capture, irrigation, crop production, harvest and handling, and food preparation and consumption. Thus, we focus on the fourth category of policy options— reducing risk to farm households, communities, and consumers.

 
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