Water quality information - DRINK WELL WATER? IT PAYS TO MANAGE YOUR WATERSHED | APEC Water

Well waters, just like surface waters demand management principles that seek to protect and preserve the water source. Well waters, because they are below the ground and seem to produce water somewhat 'magically' demand perhaps even more direct management of the watershed which produces the well water. So just what is watershed management? And why should you be interested in it? Watershed management is planning, guiding, and organizing land use so that desired goods and services are produced from a watershed without harming soil productivity and water resources. Goods and services produced from watersheds include food, forage for livestock and wildlife, wood and other forest products, outdoor recreation, wildlife habitat, scenic beauty, and water.

Essential to watershed management is the recognition that production must be accompanied by environmental protection. The specific objectives of watershed management depend on human needs in a particular area and can include:

• the rehabilitation of degraded lands;
• the protection of soil and water resources under land-use systems that produce multiple products of the land; and
• the enhancement of water quantity and quality. Rehabilitating degraded lands is sometimes mistakenly thought of as the only role of watershed management.

Rehabilitation requires that both the productivity and hydrologic function of degraded lands be restored. This usually entails the construction of engineering structures, such as gully control dams, followed by vegetation establishment, protection, and management, all of which are needed to achieve long-term healing of the landscape.

Most fundamental to watershed management is the prevention of land and water resource degradation in the first place. To achieve this goal, land use must adhere to conservation practices that avoid land degradation. The greatest potential for degradation arises from road construction, mining, crop cultivation, logging, and overgrazing by livestock in steep terrain. When management guidelines are not followed, soils erode and land productivity is diminished. The loss of soil and vegetative cover reduces the effectiveness of watersheds in moderating the flow of water, sediment, and other waterborne substances. As a result, damage to aquatic ecosystems and human communities can occur in areas that are positioned downslope or downstream. To achieve sustainable land use, the development of and adherence to land-use guidelines and conservation practices must become commonplace.

Preventing degradation of wetlands and riparian land is of particular environmental concern. These soil-vegetation communities require special management and protection because the wet soils are susceptible to excessive erosion. Furthermore, riparian vegetation provides valuable wildlife habitat and plays a critical role in protecting water quality. In some parts of the world, watershed management can be aimed at enhancing water resources. In some instances, vegetative cover can be altered to increase water yield or to change the pattern of water flow for beneficial purposes.

No matter what the specific objectives, watershed management recognizes that human use of land is usually aimed at producing a variety of goods and services, of which water is one product. By following the principles of soil and water conservation, land and natural resources can be in common usage, the term water table expresses the surface dividing the unsaturated and saturated groundwater zones. More accurately, the water table lies within the saturated zone and separates the capillary fringe from the underlying phreatic zone. The phreatic zone is the area in which water will freely flow from pores in the geologic material. Within the capillary fringe, however, water is drawn upward from the phreatic zone by capillary action within the pores of the material. Smaller pores produce greater capillary force and cause the water to rise higher, resulting in a thicker capillary fringe. The pores in the capillary fringe are fully saturated, as are those in the phreatic zone.

However, the capillary action causes the water in the pores to have a pressure that is lower than atmospheric pressure. Water is not able to flow out of these voids. A more precise definition of the water table is the surface within the saturated zone along which the hydrostatic pressure is equal to the atmospheric pressure. Water below this surface has a pressure that is greater than atmospheric pressure while water in voids above is at a pressure that is less than atmospheric pressure.