Monday, July 8, 2013

Drought Water Restriction Apply to Well Owners

If you own a well in a region besieged by drought you need to follow drought water restrictions and reduce you water use to prevent your well from going dry. Wells are not immune to drought though you may be legally exempt from water use restrictions. A deeper well may be slower to be impacted by drought conditions, it may also take longer to recover. The groundwater level fluctuates based on the amount of water added through precipitation and the amount removed by springs, stream flow and pumping. During dry periods there is little rainfall to refill the groundwater, but water use continues and sometimes increases. Not too surprisingly, during a drought, the groundwater level in a well drops. Areas with a history of low well yields, or low yielding wells are most susceptible to going dry during droughts, but most wells are susceptible to problems during drought.

The water level in an aquifer can be lowered if nearby wells are withdrawing too much water the impact of over-pumping is determined both by geology and pumping volume. This often happens during drought when there is too little rain when wells are used to irrigate crops, water live stock and water lawns and ornamental gardens. It is important during severe drought for well owners to respond to drought declarations and restrictions. There are locations where the water use restrictions do not apply to private well owners, but private wells are not exempt from the limits of nature. The most likely result of excessive use of well water during a drought will be your well going dry, but excessive water use could impact nearby wells. The ability to impact neighbors depends on geology and pumping rate, but you may need to work with your neighbors to manage your water supply.

Groundwater is found in aquifers below the surface of the Earth. This water supplies all wells- private, public and irrigation. The amount of groundwater that can be sustainably used is determined by the amount of rain and snow melt that recharges the groundwater each year and the storage capacity of the geology for variation between wet and dry years. Nature determines the amount of water that is available- geology, weather and climate. We, mankind, determine the amount of water that is used. The groundwater level fluctuates based on the amount of water added through precipitation and the amount removed through wells, but also by, springs, streams, and lakes. During dry periods, there is little rainfall to refill the groundwater, but water use continues. Not too surprisingly, during a drought, the groundwater level will drop.

Areas with a history of low yielding wells are most susceptible to problems during droughts. To provide a reliable supply of water, a well must intersect fractures and the spaces between rocks that contain ground water. This water flows into the drilled well at what is called the recharge rate. The recharge rate is the well yield and is typically measured when the well is drilled. To adequately supply a home, the volume of water in the well and the recharge rate combined must meet the household demand. Overnight there is little demand, but toilet use, showers (or baths), laundry create a peak demand during the mornings. The typical domestic demand can be met with a well that produces 5-8 gallons per minute, but adequate water storage either in the well bore itself or a cistern can allow a low producing well to adequately supply a home. Be aware that over time the yield of a well tends to fall as a well gets older. Groundwater enters a well through fractures in the bedrock and overtime debris, particles, and minerals clog up the fractures and the well production falls. According to Marcus Haynes of the Prince William Health District, the drop in water recharge rate could be 40-50% or more over 20-30 years. So, what was an adequate well 20 years ago may no longer be. It is usually during a dry summer that this is discovered.

The water level in a well usually fluctuates naturally during the year. Groundwater levels tend to be highest in the early spring in response to winter snowmelt and spring rainfall when the groundwater is recharged. Groundwater levels begin to fall in May and typically continue to decline during summer as plants and trees use the available shallow groundwater to grow and streams draws water. Natural groundwater levels usually reach their lowest point in late September or October when fall rains begin to recharge the groundwater again. In a drought year the water level in a well might not recover and continue to decline into the next year. An extended drought can lower the water level below the level of the pump, reduce flow to the well or dry out the well completely.

For a well to function and to supply water to the home, the pump must be within the saturated zone. The groundwater level can drop below the pump level especially during the summer or during a drought. If your well begins to pump air, if the pump seems to run constantly, or if you notice surging or bubbles in the water the groundwater level might be dropping below the pump. A temporary fix might be to lower the pump in the well, but this will do nothing to increase overall water availability. A typical six and a quarter inch well stores about a gallon and a half of water per vertical foot. Lowering the pump will not increase the amount of water in the well. If the well cannot recharge at the same rate at which water is being pumped out of the well, and does not have enough storage in the well, the home will suffer intermittent episodes of severe water pressure loss or possibly even total water loss. If you have water first thing in the morning and again when you get home from work, but the supply seems to run out especially when doing laundry or taking a shower your well is no longer adequate to supply the home. If this happens during a drought, water conservation measures and reducing overall household water use might be enough to survive a reduced recharge due to drought and recover when the rains finally come. However, wells that begin to produce cloudy, muddy, or sandy water may be drying out completely.

In the well, a diminished water supply can be caused by drop in water level in the well due to drought or over pumping of the aquifer, or the well could be failing (do not forget that equipment problems are the most common cause of well failure). Once your well has been impacted you are going to have to take action, addressing the problem could be as simple as implementing water conservation strategies and measures, or could require replacing water fixtures, lowering a pump or deepening or replacing the well. Your well is not unlimited and you need to be aware of your water use. The US Geological Survey, USGS, collected and compiled daily water use data for the nation and there are tremendous differences regionally and even from state to state. In Maryland average domestic water use was reported to be 109 gallons/day per person while here in Virginia the average water usage was 75 gallons/day per person. Pennsylvania to the north uses an average of 57 gallons/day per person. Ironically enough, in Nevada, an arid state, the average daily water use is 190 gallons/person. While it is clear that climate has an impact on water use, the USGS offers no explanation why Maryland uses more water than neighboring Virginia or Pennsylvania.

Water use within the home can be significantly reduced through changes in habits and by installing water-saving devices. If you have low flow toilets and are home all day, your daily water use for flushing would be 8.2 gallons versus 25.5 gallons for an older toilet. Laundry is the second largest use of water after toilets. A top loading washing machine uses 43-51 gallons per load while a full size front load machine uses 27 gallons per load and some machines have low volume cycles for small loads that use less. Replacing a top load washing machine with a front load machine saves 24 gallons of water per load of laundry. A standard dishwasher uses 7-14 gallons per load while a water efficient dishwasher uses 4.5 gallons per load. For bathing and brushing teeth low flow faucets and showerheads and behavior modification (not running the water while you brush your teeth or shorter showers can save about a third of the water typically used for personal hygiene, reducing the typical 28 gallons a day to 19 gallons a day. Do not forget to check your home for plumbing leaks both large and small. According to the U.S. EPA, one out of every 10 homes has a leak that is wasting at least 90 gallons of water per day.

In emergency situations, changes in water use habits can provide quick reductions in water use, but low flush toilets and a front load washing machine will reduce your water use by 25%-50% depending on your water use habits. If you have water supply problems it is advisable to hire a well driller or a licensed well and pump service company to determine your water level and recharge rate. They can tell you the amount of water that you are dealing with and you can determine your best response. As a well owner I believe that my water regular water use, my water overhead should be as low as possible, my home has all low flow water fixtures, but if a well is truly failing, well repair or replacement is your first expenditure. The USGS maintains a series of monitoring wells that in many parts of the country can be accessed on-line to get a general idea of the groundwater conditions in your region. There are a group of 20 groundwater monitoring wells in Virginia that measure groundwater conditions daily and can be viewed online. One of the Virginia wells is just up the road from me in the same groundwater basin and serves as my proxy for my groundwater conditions.

If you are in Virginia and you need help or advise with a well issue you can call or email the Virginia Master Well Owner’s Network for help there are volunteers and extension agents available to help you. My name and email are in the bottom third of the list with the volunteers and I am happy to help anytime.

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