Thursday, September 11, 2014

Have You Seen Groundwater?

by Ann Bleed, Groundwater Foundation Board Member

Groundwater is one of the most difficult natural resources to manage because it is so hard to see and observe. In fact, most people never see groundwater, although some can say they have seen it, at least momentarily, as it is transformed to surface water at a groundwater spring or artesian well. Some may have felt it as a sudden area of cold water caused by a groundwater spring flowing into a river or lake.

Even scientists have trouble observing and understanding groundwater. In most cases the best a groundwater scientist can do is build a groundwater model to try to describe how an aquifer works. Because groundwater flow varies depending in part on the type of subsurface materials through which it flows, the first step toward understanding how groundwater moves is to map the horizontal area and vertical depth of the subsurface layers of gravel, sand, silts, and clays in the aquifer.

Until recently, scientists have had to rely on drilling test holes and describing the various subsurface layers in each hole, a very costly and laborious process. Because of the cost, test holes are usually far apart, leaving the task of determining what the aquifer is like between test holes to a geologist who makes the best guess possible of what might be going on between the test holes.

Today, however, there is a new technique that makes exploring an aquifer more precise and less costly. Airborne electromagnetic or AEM surveying, uses a sophisticated sensor towed by a helicopter to identify and evaluate the geology within an aquifer. To the unknowing citizen the sensor may look like a bomb, so before the Lower Platte South Natural Resources District in Nebraska used AEM to survey one of its aquifers, the District made sure it issued press releases to tell the public what was going on.

This technique is fascinating to watch and already has provided a great deal of valuable information all over the world. And, thanks to the Lower Platte South Natural Resources District, the Nebraska Educational Telecommunications network and QUEST, a joint-venture science program affiliated with PBS, you can watch a seven-minute video of how this system works at


Friday, September 5, 2014

A Unique Drinking Water Situation

by Jennifer Wemhoff, The Groundwater Foundation

The Groundwater Foundation's hometown of Lincoln, Nebraska is home to a unique drinking water situation.
 
The City draws groundwater from 40 vertical wells, which are commonly used to supply drinking water. However, two additional wells, constructed horizontally underneath the Platte River, produce great amounts of water, which is then treated and piped from nearby Ashland, Nebraska. This is considered groundwater under the direct influence of surface water.
 
Why so far away? The water under the City of Lincoln is too salty for drinking. In fact, the first city-owned well for drinking water was drilled in 1875 and found to be salty; the artesian well became famous for its "curative powers, and people traveled from miles around to fill buckets and jars." Additional wells were dug throughout the city, but abandoned when the water became salty.
 
Recent drought led the City to install a third horizontal collector well to meet demand for Lincoln's increasing population. The new well became operational in July, and according to the Lincoln Journal Star, is one of the 10 largest of its kind in the nation. It has the capacity to produce 20 million gallons of water per day under normal river conditions.
 
Members of the NeWHPN tour the City of Lincoln's
horizontal collector wells.
The Journal Start also describes the well: "The horizontal well consist of a concrete silo 16 feet in diameter sunk about 70 feet into the ground to access the most productive layer in the aquifer. From the silo, well screens are projected horizontally below the river. its construction allows the well to provide at least 10 million gallons per day during extended drought conditions with low river flows."
 
A fourth horizontal well is on the horizon as well, being planned for completion in 2018.
 
The Nebraska Wellhead Protection Network (NeWHPN), facilitated by The Groundwater Foundation, took a tour of the collector wells as part of its meeting on September 4, 2014.

Is your community water system unique? If you don't know, ask! Every water customer has the right to be informed about a community's drinking water supply, and its quality. Ask for a copy of the latest Consumer Confidence Report (CCR) to learn more about your drinking water. Find out more about the CCR here: http://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfm.



Tuesday, August 19, 2014

Gear Up for Protect Your Groundwater Day on September 9th!

Protect Your Groundwater Day is only three weeks away! Started by the National Ground Water Association, Protect Your Groundwater Day is the perfect time for every household to act to protect this precious resource.  The Protect Your Groundwater web page provides ways citizens can protect groundwater from overuse or contamination. Here are a few more suggestions for ways you can protect groundwater every day of the year:

Everyone

When it comes to hazardous household substances:
  • Store them properly in a secure place
  • Use them according to the manufacturer's recommendations
  • Dispose of them safely (if in doubt as to how, contact your local waste authority)
When it comes to water conservation:

 

If you own a water well

To learn more about groundwater protection, visit www.WellOwner.org or www.groundwater.org.