Assessing non-point source pollution models: a review

Although access to clean and potable water is a requirement for healthy living, the constant release of non-point source pollutants into water bodies has resulted in water quality degradation. In a bid to curb this situation, water quality models are used as a tool. This study reviews 10 non-point source models, namely: AGNPS, ANSWERS, CREAMS, SWRRB, HSPF, SWAT, EPD RIV1, DMA, CMBA, and MA, giving consideration to their nature, components, area of use, strengths, and limitations. Our review indicated that hydrological processes and mechanisms involved in the movement of non-point source pollutants have not been completely developed in these models. However, HSPF and EPD RIV1 models (which have in-stream process components) are limited due to limitations in their operations and computational difficulties. Further research would seek to develop a non-point source pollutant model that would not only adequately and effectively simulate non-point source pollutants in water bodies, but would also be easy to assess, user-friendly, and time-efficient.