Safe application of reclaimed water reuse for agriculture in Korea

Abstract

This article describes the pilot study on the water reuse for agricultural irrigation in Korea. The project is a part of the application of wastewater reuse system for Agriculture project, a 21st Century Frontier R&D Program sponsored by the Ministry of Education, Science, and Technology and associated with the Sustainable Water Resources Research Program. The goal of the project was to develop infra-technologies necessary to reclaim wastewater for irrigation in agriculture. The project involved two phases: laboratory and field research. Reclamation techniques for irrigation and feasible reuse were developed as a first step in proposing appropriate water quality standards. Reclaimed wastewater of various qualities was used to irrigate cereal crops and vegetables, and possible adverse effects on crops, humans, and the environment were investigated. The optimal reclamation methods required to satisfy water quality standards were explored and the operational characteristics investigated. Moreover, an inventory of farmlands that could reuse reclaimed wastewater was established. Feasible delivery systems for irrigation were developed, and pilot project sites were identified. Finally, operational field data from pilot units were collected and analyzed. This research and development may help solve water shortage problems in Korea, which left unaddressed will have an adverse effect on future generations.

Irrigation Water Quality Standards for Indirect Wastewater Reuse in Agriculture: A Contribution toward Sustainable Wastewater Reuse in South Korea

“…It was also found that the total coliform of the irrigation water containing untreated wastewater was about 77,000 MPN/100 mL [21]. QMRA on paddy irrigation showed that the human health risk of irrigating treated wastewater is nine times higher than that of irrigating groundwater [42], but even with the extremely high level of total coliform, there have rarely been any reports of human harm from using treated or untreated wastewater for rice paddy irrigation. This indicates that the subjected level of total coliform can be easily found in nature and is inadequate as an indicator for microbes.…”

“…They have also focused on the upland irrigation including vegetables and have not well considered the characteristics of irrigation water in paddy fields: Irrigation water for paddy rice production accounts for more than 70% of the total irrigation water in Asia [40], and paddy rice is the largest consumer of freshwater resources in South and Southeast Asia [41,42]. This study, therefore, examines existing water quality criteria for irrigation water and wastewater reuse, and analyzes the water quality standards of other countries to set agricultural water quality standards for indirect wastewater reuse considering both paddy and upland irrigation.…”

Classification of Wastewater Reuse for Agriculture: A Case Study in South Korea

“…Generally, farm conditions for wastewater reuse are directly associated with the health condition of the farmer and consumer (Jang et al , ). WHO () suggested the target water quality based on crop types and irrigation methods.…”

“…Reclaimed wastewater in agriculture has been considered an important alternative irrigation water resource in a growing water demand and freshwater shortage situation (Raschid‐Sally et al , ; Jang et al , ; Chang and Ma, ). Wastewater is used as irrigation on more than 20 million ha of agricultural land throughout the world, and food products from farmland irrigated with wastewater are consumed by more than 10% of the world's population (World Health Organization (WHO), ; Hamilton et al , ).…”

“…On the other hand, it was reported that there still remained some agricultural land irrigated with untreated wastewater (Song et al , ), and there has been limited research investigating various domestic examples of wastewater irrigation. Given the circumstances that agricultural water use takes up more than 48% of total water consumption and the reuse trend in Korea is generally increasing (Kim et al , ; Jang et al , ), it is important to categorize wastewater reuse culture and to introduce representative cases at local level for safe sustainable wastewater reuse in agriculture.…”