Irrigation with Marginal Quality Waters: Issues

Abstract

Due to increasingly stringent regulations on the discharge of wastewaters as well as the decreasing availability of freshwater resources, there is a need to consider the expanded use and reuse of marginal quality waters for irrigation and other purposes. This paper addresses broad issues related to the potential reuse of (1) Treated municipal wastewaters; (2) food processing wastewaters; (3) confined animal lagoon waters; and (4) saline waters, including irrigation drainage waters, on croplands and pastures, landscapes, and agroforestry systems. The long-term efficacy of irrigation with marginal quality waters is dependent on several factors, such as unique limiting water quality characteristics and site-specific crop, soil and climatic conditions. Opportunities exist to use marginal quality waters beneficially. However, their use requires more intensive management and monitoring than use of higher quality waters. Site-specific management options are used to partially overcome many of the potentially adverse impacts, but some impacts are unavoidable. In many instances, the upper bounds of wastewater usage are not fully known and potential long-term cumulative impacts on the environment require further research.