ABSTRACT
Water is one of the most precious resources on the planet. More than 1 billion people do not have access to a source of clean drinking water, and around 3 billion experience water scarcity at least one month per year. This has caused a serious threat to many parts of the world. Given the challenges of population growth, overuse of water, growing pollution, environmental degradation, and changes in weather patterns due to global warming, many countries worldwide face increasing water scarcity. Water shortages have a great impact on human health, socio-economic development, and the environment. The water cycle is a vital process as it enables the availability of water for all living organisms and regulates weather patterns on our planet. There are many human activities that adversely affect the water cycle, such as inefficient irrigation practices, use of fertilizers, manures, pesticides, animal husbandry activities, deforestation of woods, pollution due to industrial effluents and domestic sewage, combustion of fossil fuels, stream-channel alteration, mining, and changes in land use patterns. These activities can contaminate water resources, increase soil salinity, and lower the amount of groundwater. Watershed management planning is a process that results in a plan of how to best protect and improve the water quality and other natural resources in a watershed. This paper describes the necessary steps for updating a typical existing watershed management plan for the Clear Lake watershed in north central Iowa, USA as a case study. The lake is impaired for algae, nutrients, and bacteria. While significant progress has been made to reduce the amount of pollutants since 2011, there remains some work to be done to restore the water quality by 2030.