1. Watersheds Human activities and structures, as depicted
by the distribution of various examples in the conceptual
landscape, affect the interaction of ground water
and surface water in all types of landscapes.

2. Human Activities That Alter Watershed Functions
Like all organisms, humans are an integral part of the watersheds in which they live. Therefore, human activities, both in the water and on the land, can have a great impact on the watershed functions described previously. The creation of buildings, parking lots, and roads; the draining of wetlands; mining; deforestation; and agricultural activities can all alter the quality and quantity of water that flows over and infiltrates into the ground. These changes can alter watershed functions by eliminating critical water storage sites (e.g., wetlands and floodplains) and by contributing additional sediments and chemicals to runoff. Human activities can also eliminate critical natural habitat sites, thereby limiting biodiversity in the watershed

3. Watershed Functions
Because they convey the water that runs over the land and into the ground, watersheds provide many vital ecological and hydrological functions. Hydrologically, watersheds collect water from rainfall and snowmelt, storing some of this precipitation in wetlands, soils, trees, and other vegetation, and underground in aquifers. The floodplain along the banks of a river also serves as an important storage site for water during periods of heavy runoff. These natural storage sites help eliminate contaminants as suspended particles settle out and as water infiltrates into the soil where biological and chemical reactions can break down impurities. Some of this stored water eventually flows into streams, rivers, and lakes as runoff.
Ecologically, watersheds provide critical habitat for many plant and animal species, as well as transport paths for sediment, nutrients, minerals, and a variety of chemicals. Watersheds also provide water to human communities for drinking, cleaning, recreation, navigation, hydroelectric power, and manufacturing.

4. Watershed
We often think of rivers as simply water flowing through a channel, but river systems are complex and intimately connected to and affected by the characteristics of their surrounding watersheds – the land that water flows over and under on its way to the river. Everyone is an integral part of the watershed in which he or she lives. Many human activities that occur on the land, such as agriculture, transportation, mining, and construction, affect our river systems and how they function.
The purpose of this publication is to help the reader gain a better understanding of how communities are organizing at the watershed level to lessen the impact of human activities on Ohio's rivers, lakes, streams, and groundwater. A reference list is provided for those seeking more in-depth information on this topic

5. Watersheds themselves consist of all surface water and include lakes, streams, reservoirs and wetlands, as well as all groundwater and aquifers. The water in a watershed originates via precipitation that is collected on the surface and groundwater. However, it is important to note that not all precipitation falling in an area exits the watershed. Some of it is lost through evaporation and transpiration

6. It is the watershed that provides drinking water, as well as water for recreation, irrigation and industrial activities. Watersheds are also significant for plants and animals as they provide food and water.

7. The most significant however, is the pollution of watersheds
The most significant however, is the pollution of watersheds. Watershed pollution occurs in two ways: point source and nonpoint source. Point source pollution is pollution that can be traced to a specific point such as a disposal site or leaking pipe. Recently, laws and technological advances have made it possible to detect point source pollution and its problems are being reduced.
Nonpoint source pollution occurs when pollutants are found in water running off of crops, parking lots and other lands. In addition, it can also be caused when particulates in the atmosphere fall onto the land with precipitation.
Humans have also impacted watersheds by reducing the amount of water flowing within them. As people take water out of a river for irrigation and other city-wide uses, the river's flow decreases and with this decreased flow, natural river cycles such as flooding, may not occur. This could in turn hurt ecosystems depending on the river's natural cycles.

8. WHAT IS A WATERSHED?
"Watershed" is not a word common to our everyday use. Sometimes we hear of a "watershed event," but that refers to current events and not to water management. When talking about water, "watershed" refers to an area of land that drains towards a given river, lake or wetland.
Land in a watershed slopes downhill to the body of water it supplies and from which the watershed is given its name. For example, the Rum River Watershed is the land that drains towards the Rum River. High spots in the landscape, such as hilltops and mountain ridges, often mark watershed boundaries where rain or snow falling on one side goes to one river, lake or wetland, and rain or snow that falls on the other side goes to another.

9. Watersheds can be small, like an area of a field that creates a pond every spring, or huge, like watersheds for great rivers such as the Mississippi and Amazon, draining whole states and, sometimes, whole countries. A great visual description of watersheds is given in the "What is a Watershed" video — the link is
Just as a person’s character is shaped by their surroundings, the character of a river, lake or wetland is shaped by its watershed. Its water quantity (how much) and quality (how clean) depend on what is taking place in its watershed. This is why water-quality experts want people to be "watershed aware" and to "know their watershed." Usually, the fewer human activities that are going on in a watershed the healthier the body of water it supplies will be. Think about it. Where are the cleanest rivers and lakes and healthiest wetlands in Minnesota? Up north where there is the least human activity. As human activity increases in a watershed, either through farming, forestry, mining, industry, or urban development, the condition of the body of water it supplies declines.
When a river, lake, or wetland is in trouble, one of the first things water quality specialists do is look at what is going on in its watershed. They make a list of watershed activities that are harming water quality and prioritize the list from the most harmful to the least. If it is decided to improve the body of water, an action plan is developed to assist people in changing from harmful watershed activities to ones that are more water friendly.
Do you know what watershed you live in?