Water is at the core of a sustainable earth and is critical not only for economic development and healthy ecosystems, but for human survival itself. According to the United Nations Department of Economic and Social Affairs water is at the heart of adaptation to climate change, serving as the crucial link between the climate system, human society and the environment. Water must be managed efficiently and equitably to strengthen the resilience of social, economic and environmental systems under duress of rapid changes.
Water problems are becoming increasingly severe and complex. Interlinkages between water resources management and other environmental, social and economic issues are increasingly becoming more evident as the earth’s population grows and land-use changes. We are seeing the degradation of water quality from both point and non-point sources of pollution and growing impacts from a changing climate. In undisturbed landscapes the land is covered with vegetation that holds the soil on the land and filters rain water and snowmelt through the soil recharging the groundwater table or flowing into streams. An undeveloped watershed provides clean, safe water and groundwater.
As a community grows, so does the amount of surface area covered by parking lots, roads and rooftops. When development disturbs more than 10% of the natural land by covering surfaces with roads, driveways, walkways, patios, and homes the natural hydrology of the land is disturbed, irreparably disturbed. Rainfall cannot soak through these hard surfaces; instead the rain water flows across them picking up velocity and pollutants along the way. The storm water flows into ditches or storm drains, which typically dump the water, pollutants and debris carried in the stormwater into our streams and waterways.
The Gravity Recovery and Climate Experiment (GRACE) satellite mission from the National Aeronautics Space Administration (NASA) has been collecting data since 2003. The GRACE satellites measure monthly changes in total earth water storage by converting observed gravity anomalies measured from space into changes of equivalent water height this was a method developed by Matthew Rodell & James S. Famiglietti in 1999. In 2015 scientists completed the analysis of all the data from January 2003 to December 2013.
The scientists found that more than one third of Earth's 37 largest groundwater basins are using up their groundwater faster than it is being replaced. Though the GRACE satellites can be used to see the rate of net water consumption, there is little accurate data about how much water actually remains stored in the earth for future us. So we know a third of the earth is using up their groundwater, we have no idea when the water will run out.
Throughout most of history surface water (rivers and streams) served as the principal freshwater supply for mankind. However, the importance of groundwater has increased in recent decades as mankind’s demand for water has surpassed surface supplies and our ability to access groundwater has increased with technology. Fresh surface water can no longer support the needs of mankind. Accessing groundwater allowed populations to increase, and provide reliable water as surface water has become less reliable and predictable as weather patterns change and regions experience extended droughts. Groundwater is reported to supply almost half of all drinking water worldwide, and is currently the primary source of freshwater for approximately two billion people [Famiglietti, 2015].
Virginia is dependent on groundwater. According to Virginia Tech there are approximately 1.7 million Virginians who get their water from a private well. In addition, according to the National Groundwater Association there are almost 750,000 Virginians who get their water from public and private community groundwater wells. In total that means that approximately 30% of Virginians are entirely dependent on groundwater for their drinking water. There are already problems with availability, quality and sustainability of groundwater in areas of Virginia in places such as Fauquier County, Loudoun County and the Coastal Plain.
According to the GRACE data, Virginia’s aquifers are under stress. It is only a matter of time until areas within the historic boundary of the aquifers begin to go dry and in vulnerable areas begin to subside. Now is the time to identify, understand and manage our water resources.
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