Springs are water flowing or seeping out of an opening in the ground or hillside. The groundwater travels through a permeable layer, on top of a hard or impermeable layer. Usually springs show up where this hard layer is exposed such as at a bank or on a slope. Springs are particularly sensitive to seasonal changes in groundwater availability and may dwindle during dry periods.
Since springs are close to or at the ground surface, they can become contaminated when barnyards, pastures, sewers, septic tanks or drainfields are located above or near them. Surface water runoff can carry pollutants long distances where they can come into contact with spring sources. Also, rainfall can carry pollutants into the groundwater which then come out with the spring water. Does your spring have protection from pollutants?
A poorly protected spring carries the following characteristics
- Is located downhill from sources of pollution.
- Allows surface water runoff to infiltrate the soil above the source.
- The watershed is not protected from livestock or wildlife.
- The spring collection system is not fenced or is without warning signs to prevent human tampering and trespass.
- Does not have a watershed under the control of the water system operator, that is, it is owned by someone else.
A properly protected spring carries the following characteristics
- Is located uphill from pollution sources.
- Has a drainage ditch which intercepts and diverts surface water runoff away from and below the spring source.
- Has a fence built to keep livestock and wildlife away from the water intake system uphill from the spring source.
- Has warning signs posted to prevent human tampering.
- Has the watershed under the control of the operator either by direct ownership or protective covenants.
The purpose of developing a spring is to capture the natural flow of ground water before it emerges onto the surface of the ground. An improperly developed spring, such as a single pipe driven into the hillside, will most likely not collect enough water to meet normal demands and may become clogged easily.
The two main methods of properly developing a spring are:
1. Perforated pipe collection system
The "spring" flow is intercepted by a system of perforated pipes installed within the water bearing strata and laid in gravel packed trenches. The water is then delivered to a storage tank without coming into contact with the surface of the ground.
2. Spring box collection system
A water-tight basin is set into the ground, to the bedrock, or impermeable layer. The tank usually has an open bottom that captures the spring water. The bottom is usually filled with stone, brick, or other material that allows water to enter the tank while holding back the surface soils.
The spring box or storage tank should have:
- A valved drain to permit draining for cleaning and maintenance. The opening must be screened to keep out animals and insects. The outlet for the drain should be at the lowest elevation in the spring box to allow for complete draining and cleaning of the box. The outlet should be drained below the spring box to a non-erosive outlet. (Gravel or larger stones will eliminate soil erosion from below the outlet drain.)
- A screened overflow.
- A screened, valved supply pipe located about six inches above the floor.
- A closed, locked, watertight cover to prevent surface water runoff contamination, insect intrusion and human tampering
The water is supplied to the houses through a distribution system which includes a network of pipes, valves, meters, and other fixtures between the storage tank and the houses being served.
- Some distribution systems may include a booster pump to push water uphill to customers not able to be served by gravity, while others simply use gravity flow.
- A positive pressure of at least 30 psi should be maintained throughout the system. Many water using devices within the house must have this pressure to work satisfactorily.
- If fire flow is provided, a pressure of at least 20 psi throughout the system should be maintained. (Increased storage will be required to meet fire flows.)
Follow these routine operation and maintenance procedures:
After an initial analysis, the operator of a spring must submit a water sample for coliform analysis (bacteria) at least once every 12 months and one sample for nitrate analysis at least once every 36 months. The coliform sample may be required more often, depending on the source, protection, development and past bacteriological sampling history.
Spring collection chambers should be disinfected 1) prior to use; 2) anytime the spring or storage box has been emptied or opened; 3) when coliform test results are unsatisfactory; or, 4) yearly.
- Determine the capacity of the spring chamber or storage tank in cubic feet and multiply by 7.5 to determine the number of gallons. (Volume = length x width x depth X 7.5 gal/cubic foot = gallons.)
- For each 1000 gallons of capacity, add 1 gallon of sodium hypochlorite (household bleach). This will make a chlorine concentration of 52 milligrams/liter (52 parts per million).
- Be sure to add the bleach into the water (small into big) and have adequate ventilation. It is always best to mix the chlorine solution outside of any confining space.
- NOTE: NEVER ENTER A CONFINED SPACE WITHOUT ADEQUATELY VENTILATING THAT SPACE TO THE ATMOSPHERE FOR SEVERAL HOURS. IF IT IS NECESSARY TO ENTER A CONFINED SPACE, YOU SHOULD HIRE A PERSON TRAINED AND/OR CERTIFIED FOR CONFINED SPACE WORK.
- Mix and wash interior walls above the water level using a clean broom or brush. Scrub the walls to remove slime and prevent algae. Run water through the overflow and drain. DO NOT DRAIN into a septic tank, stream, wetland or lake.
- Allow at least 24 hours of contact time to kill bacteria. It may be necessary to shut off the flow to keep the water level at the top of the storage tank.
- Allow chlorinated water to flow to each residence until chlorine smell can be detected at each residence to disinfect to the system piping. Do not use the chlorinated water during this period.
- After 24 hours or more have elapsed, flush the system to remove all traces of chlorine. Again, DO NOT DRAIN into a septic tank, stream, wetland or lake. Any water being discharged to the ground should not have any chlorine in it. Use chlorine test strips to check chlorine content before emptying the spring box or storage tanks. Also, there must be no chlorine in the water sample.
- Collect a water sample for coliform testing. If results are unsatisfactory repeat disinfection process until coliform tests are acceptable. If satisfactory results cannot be obtained, even after chlorination and repair, a chlorinator can be added to the system to eliminate bacteria. Please contact the health department for information about chlorinators.
- Coliforms are a large group of bacteria which commonly live in the intestinal tract of animals and humans.
- Most coliforms are harmless. They are indicators of water contamination by human or animal wastes. Coliforms are used as indicator organisms because:
- They are often more numerous, longer living and easier to find than disease-causing organisms or pathogens.
- They are typically less susceptible to treatment and disinfection than pathogens.
Therefore, the absence of coliforms in drinking water is a good indication that disease causing organisms are not present.
- Sewage and animal wastes contain many pathogens such as protozoa, bacteria and viruses. Specific examples include Cholera, Typhoid, Hepatitis A, Giardiasis and Dysentery (diarrhea.)
- Common symptoms of waterborne disease include diarrhea, cramps, nausea and possibly jaundice.
However, coliforms are not a perfect indicator of the actual or potential presence of pathogens. Protozoans such as Giardia, Cryptosporidium and Cyclospora are more resistant to treatment and disinfection which remove coliforms. These protozoa are commonly found in surface water and may be present in improperly protected or developed springs. Symptoms of these diseases include diarrhea, stomach cramps, vomiting, weakness and slight fever.
Sources of nitrogen include sewage systems, animal feedlots, manure storage facilities and fertilizers. Once in the soil, microorganisms convert nitrogen to nitrate. Nitrate not absorbed by plants is transported to ground water by rainfall.
Nitrate, the chemically active form of nitrogen, causes Methemoglobinemia or Blue Baby Syndrome. Methemoglobinemia is a life threatening condition in infants. Nitrite reacts with hemoglobin (the oxygen carrier in the blood) and changes it to methemoglobin. Methemoglobin can not carry oxygen; this leads to oxygen starvation and in extreme cases, suffocation.
Nitrite can also be converted to other compounds which have been known to cause cancer in laboratory animals. It is therefore assumed that these compounds could increase the risk of human cancer, although there is no direct evidence for this.
For these reasons nitrate sampling and analysis is required at least once every 36 months. Laboratories report nitrate test results either as nitrate (NO3) or nitrate-nitrogen (NO3 - N). The acceptable levels are 45 milligrams/liter for nitrate and 10 milligrams/liter of nitrate-nitrogen.