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1. Toxic Algae- Precautions & Facts
By Tadd Barrow, UNL Extension Educator
What is toxic blue-green algae?
Although it technically is not a true algae, what is commonly referred to as toxic blue-green algae refers to certain strains of cyanobacteria that produce toxins. These toxins were found in a number of Nebraska lakes in 2004 and 2005.
Toxic blue-green algae can dominate the algal populations of a lake under the right combinations of water temperature, low water depths, and nutrients (such as, high nitrogen and phosphorus concentrations from wastewater discharges and/or runoff from agricultural land and communities).
What should I look for to avoid toxic algae?
The toxic strains of blue-green algae usually have heavy surface growths of pea-green colored clumps, scum or streaks, with a disagreeable odor and taste. It can have a thickness similar to motor oil and often looks like thick paint in the water. Algae blooms usually accumulate near the shoreline where pets and toddlers have easy access and the water is shallow and more stagnant. It is important to keep a watchful eye on children and pets so that they do not enter the water. Aspects to watch out for include:
- Water that has a neon green, pea green, blue-green or reddish-brown color.
- Water that has a bad odor.
- Foam, scum or a thick paint-like appearance on the water surface.
- Green or blue-green streaks on the surface, or accumulations in bays and along shorelines.
What are the risks and symptoms?
Pets and farm animals have died from drinking water containing toxic blue-green algae (or licking their wet hair/fur/paws after they have been in the water). Blue-green algae toxins have been known to persist in water for several weeks after the bloom has disappeared.
The risks to humans come from external exposure (prolonged contact with skin) and from swallowing the water. Symptoms from external exposure are skin rashes, lesions and blisters. More severe cases can include mouth ulcers, ulcers inside the nose, eye and/or ear irritation and blistering of the lips. Symptoms from ingestion can include headaches, nausea, muscular pains, central abdominal pain, diarrhea and vomiting. Severe cases could include seizures, liver failure, respiratory arrest – even death, although this is rare. The severity of the illness is related to the amount of water ingested, and the concentrations of the toxins.
Are some people more at risk?
Yes. Some people will be at greater risk from toxic blue-green algae than the general population. Those at greater risk include:
- Children. Toddlers tend to explore the shoreline of a lake, causing greater opportunity for exposure. Based on body weight, children tend to swallow a higher volume of water than adults, and therefore could be at greater risk.
- People with liver disease or kidney damage and those with weakened immune systems.
Here are some tips on what you can do, and things to avoid:
- Be aware of areas with thick clumps of algae and keep animals and children away from the water.
- Don’t wade or swim in water containing visible algae. Avoid direct contact with algae.
- Make sure children are supervised at all times when they are near water. Drowning, not exposure to algae, remains the greatest hazard of water recreation.
- If you do come in contact with the algae, rinse off with fresh water as soon as possible.
- Don’t boat or water ski through algae blooms.
- Don’t drink the water, and avoid any situation that could lead to swallowing the water.
Is it safe to eat fish from lakes that are under a Health Alert?
The toxins have been found in the liver, intestines and pancreas of fish. Most information to date indicates that toxins do not accumulate significantly in fish tissue, which is the meat that most people eat. It is likely that the portions of fish that are normally consumed would not contain these toxins. However, it is ultimately up to the public to decide whether they want to take the risk, even if it is slight. Fishing is permitted at lakes that are under a Health Alert, but anglers may want to consider practicing catch and release at these lakes.
Where can I find out more information about lake sampling for toxic algae?
The Nebraska Department of Environmental Quality is conducting weekly and monthly sampling at select public lakes that are either popular recreational lakes, or have historically had toxic algae problems. This information is updated weekly on the agency web site, www.deq.state.ne.us .
What should I do if I have concerns regarding a private lake?
As part of the University of Nebraska Water Quality Extension Program, UN-L has developed a "Volunteer Monitoring Program" and lake test kits that will be sent to interested lake associations, owners, etc. so they can collect a sample and send it to UN-L for analysis. To obtain more information and a test kit please contact the program at (402) 472-7783, or (402) 472-8190.
If I think a public lake has a toxic algae bloom, who do I call?
Please contact the Department of Environmental Quality’s Surface Water Section at (402) 471-0096, or (402) 471-2186.
If I am experiencing health symptoms, who do I call?
If you experience health symptoms, notify your physician, and also report it to the Nebraska Health and Human Services System at (402) 471-2937. You can also contact the Nebraska Regional Poison Center at 800-222-1222 for more information.
The development of this factsheet was a cooperative effort by:
Brian McManus, Department of Environmental Quality, (402) 471-4223,
Kathie Osterman, Communications and Legislative Services, (402) 471-9313
Jim Carney, Game and Parks Commission, (402) 471-5547
Tadd Barrow, UNL Water Quality Extension, (402) 472-7783
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2. Private Waters Stocking Program
By Jeff Blaser, Nebraska Game & Parks Commission Private Waters Specialist
The Nebraska Game and Parks Commission will provide largemouth bass, bluegill, and possibly trout, for stocking new, privately-owned waterbodies (ponds, sandpits, lakes, etc.) or qualifying waterbodies where the Commission has recently authorized the existing fish populations to be chemically removed.
To be eligible for state fish, private waterbodies must be:
- One-half surface acre or larger in size and one-fourth of the surface area must contain a depth of at least 10 feet. There maybe exceptions for spring fed ponds, natural lakes, and others at the discretion of the inspecting biologist.
- No other fish should be present at the time of stocking, with the exception of recently stocked channel catfish.
- Waterbodies must also have a minimum water clarity of 12 inches and fencing to exclude livestock will be required under most circumstances.
- A valid Nebraska fishing permit is required of every person 16 years of age and older who fishes these ponds, and all anglers must comply with current fishing regulations.
Young-of-the-year bluegills will be available during the fall and largemouth bass during the following spring. Coldwater ponds capable of supporting trout throughout the year can be considered for an initial fall trout stocking. Owners of these year-round trout supporting ponds, who allow reasonable public access, may also receive supplemental fingerling trout stockings.
Interested waterbody owners, who think they meet the minimum requirements previously mentioned, can contact either the nearest Commission fisheries biologist or the Lincoln based private waters specialist and request copies of the stocking policy and stocking application. All applications for fish must be returned by August 1 to be considered for stocking during that calendar year. If a pond has multiple owners, all landowners must concur with the stocking request or the application will be denied.
A site inspection will be conducted and a request for fish submitted/authorized if the waterbody qualifies. Although owners of state-stocked waters are not obligated to allow unlimited public fishing access, they cannot charge anglers a fee to fish and are urged to grant access to anglers who ask permission to fish. These same owners should establish fish management goals they would like to accomplish with their pond’s fish populations and advise anglers of them when fishing access is granted. Pond owners should also monitor what is being caught, released, and harvested, in order to make sure their management goals are being attained/maintained.
Once ponds have been authorized to receive fish, the pond owners will likely have to meet the distribution truck at a specified, strategic location. Pond owners will be instructed on what they will have to bring to transport fish to their respective ponds. The hauling containers should have a trash big liner and be half-filled with fresh water from the ponds just before the fish are picked up.
Upon arrival at the pick-up site, the water in the container is tempered to closely match the temperature of the water in the fish hauling truck. Fish are then added and the water oxygenated. Finally, the bag is sealed and the container is ready for the trip to the pond.
Get the fish to the pond as quickly as possible to ensure their survival. Transportation delays can cause oxygen levels in the water to drop and water temperatures to rise, resulting in stressed or even dead fish.
Do not pour the fish in to the pond right away. Fish must be acclimated to the changes in water chemistry first, or they can go into shock and die. This is especially important if the water temperature in the containers has risen and is more than 5 to 10 degrees different from the water in the pond. During the course of 15 to 30 minutes, mix pond water into the water of the container, than place the container into the pond so that fish can swim out when they are ready. Or, partially submerge the container into the pond, allowing the water to be slowly exchanged, until the chemistry is similar to that of the pond.
Be careful while handling the fish; any wounds created may eventually become infected with bacteria or fungi. Although fish may swim away, they may die later from these infections.
For more information, contact Jeff Blaser, Nebraska Game & Parks Commission, ( 402) 471-5435.
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3. Pumping Water For Ponds
By Tom Dorn, UNL Extension Educator
Occasionally, I visit with an acreage owner who would like to build a small fishing/swimming pond on their property but their land area or topography is such they cannot count on surface runoff or natural springs to contribute any significant portion of the water needed to fill the pond or keep it full. Eventually, the discussion turns to the feasibility of using a well to pump the water for the pond. Invariably, the acreage owner is surprised by the amount of water it takes.
Lets crunch some numbers for an example pond 150 feet by 150 feet. This pond would have a surface area of just over half an acre. If the depth in the middle of the pond is 10 feet and the sides have a 1:3 slope (1 foot vertical drop for each 3 foot horizontal run), the volume of the pond would be 153,000 cubic feet or a little over 1.1 million gallons.
Domestic pumps usually deliver between eight and twelve gallons per minute (gpm) but lets assume the well driller can find an adequate aquifer and installs a 20 gpm pump. Assuming the full 20 gpm flow goes only to the pond (not split between domestic needs and the pond), it would take between 40-60 days of continuous operation to fill the pond initially, depending on initial seepage losses.
If we assume 30 inches of direct annual rainfall per year but no appreciable runoff into the pond, the evaporation and seepage losses not made up by rainfall will average about 0.25 inch per day. A quarter inch of loss per day over a half acre is equal to 3400 gallons of water per day. This would require running the 20 gpm pump about 1000 hours a year to keep the pond full.
Each half acre pond requires about 1.1 million gallons of water to fill initially and about 1.2 million gallons of pumped water a year to keep full. By way of comparison, a family of four will use about 250 gallons of water per day (91,250 gallons per year) for domestic uses. If the family also irrigates a 10,000 square foot (0.23 acre) lawn an average of 0.75 inch per week from May 1 through September 30, the total water used for the acreage more than doubles, (194,000 gallons).
A half-acre pond therefore “consumes“ about as much water to fill initially as a family of four would have used for the household and lawn in six years. It will then require as much water each year to keep full as the family would have used in 6.5 years. A question I always ask an acreage owner considering a groundwater fed pond are, “Is this a sustainable use of our limited groundwater resource in eastern Nebraska?”
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4. Supervision Is Key To Safety Around Pools
By Sharry Nielson, UNL Extension Educator
Drowning ranks second only to motor vehicle mishaps as the most common cause of accidental death for children. Children under age four are at especially high risk. Even adults are at risk in water muddied by silt, plants, and fish.
It takes only a few moments and an inch of water for a child to drown. Small children have been known to drown in 5-gallon buckets. Most drownings, however, occur when a child is left alone or accidentally falls into a pool or pond.
Farm ponds can look inviting, but many times they are deep with a sudden drop off. A person can go from knee deep water to water that is 50 feet deep in seconds. Additionally, weeds growing from the bottom can entangle a person, making it difficult or impossible to return to the surface.
If you live close to a pond or irrigation source, take steps this spring to keep your family safe. Begin with these:
- Provide children over 3 years with swimming lessons.
- Fence off ponds and other water areas as feasible.
- Never leave a young child alone in water, even in a bathtub. A child can drown in the time it takes to answer a phone call.
- Adopt a “swimming buddy” policy for children. Where swimming is allowed, be sure children always swim with a friend or adult.
- Insist that children use personal flotation devices, such as buoyant vests, cushions or rings.
- Keep rescue equipment near water areas. Purchase a flotation device or make one from a gallon plastic jug, and attach a rope. Install a safety post near the pond. Tie the loose end of the rope to the post. Add a laminated poster with instructions on how to use and other water safety tips near the top of the post.
- Teach older children and teens “Reach, Throw, and Wade”, so they do not risk their lives to help a drowning victim.
- Be sure all swimmers know how to get help quickly. Older teens and adults learn CPR.
- Never swim during storms or lightning.
Drowning rates are three times higher in rural areas than in urban, and often occur in water like farm ponds and irrigation canals. Summer and water go together, so help keep your family safe with adult supervision of young children and teaching water safety measures to all family members.
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5. Septic Tank and Drainfield Location
By Sharon Skipton, UNL Extension Educator and
Jan Hygnstrom, UNL Extension Project Manager Biological Systems Engineering
Septic systems can contribute to surface water pollution of nearby lakes, rivers, or ponds. Possible pollutants include bacteria, phosphate, and nitrate. To provide some protection for surface water, minimum setback distances are required. The septic tank and the drainfield must be located at least 50 feet away from all surface water. In addition, there must be at least four feet of unsaturated soil between the bottom of the drainfield and the highest groundwater elevation. Since drainfields might be installed with the bottom about three feet below the soil surface, the highest groundwater level must be at least seven feet below the soil surface.
Additional setback requirements are designed to protect the environment and human health. In particular, the septic tank must be located at least 50 feet away from any private drinking water well; and the drainfield must be located at least 100 feet away from any private drinking water well. Each needs to be at least 500 feet away from a community drinking water well.
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6. Rain Gardens
By Kelly Feehan, UNL Extension Educator
Rain gardens are landscaped areas planted to flowers, ornamental grasses and sometimes shrubs. What makes them slightly different than other landscape beds or gardens is they are located and designed to catch and soak up rain water.
This gardening concept has been brought about by water quality and quantity concerns. With each rainfall, snowmelt or excess irrigation, water flows over the land picking up sediment and other pollutants and deposits these in ponds, lakes, streams and rivers.
Rain gardens are located where they will catch rainwater from the homes roof and/or lawn area. This conserves water and reduces the amount of run-off pollution that reaches surface water from a property.
Rain gardens are not ponds or bogs and they are not mosquito breeding grounds. If properly located and designed, water that collects in a rain garden should disappear in less than 48 hours.
A typical rain garden is 100 to 300 square feet and crescent, kidney or teardrop shaped. The size is determined by the size of the area draining to it and soil type. As a rule, rain gardens should be 20 to 30 percent of the size of the drain area in sandy soils and 60 percent of the drain area in clay soils.
Unlike the more common raised planting berms, rain gardens are slightly sunken. They range from four to eight inches deep and have level bottoms so water spreads evenly and does not pool at one end of the garden.
A rain gardens depth is determined by the properties slope. On less than a four percent slope, rain gardens are ideally three to five inches deep; six to seven inches deep on five to seven per cent slopes; and eight inches deep on properties with an eight to twelve percent slope.
Rain gardens are not recommended for areas with greater than a 12 per cent slope or which have compacted clay soil. They should not be located where water already tends to pool and sit as this is an area with poor drainage. It is best not to place them directly beneath a tree.
Rain gardens do need to be at least ten feet from the house and at least 25 feet from a septic system and wellhead. Ideally, they are located where soil drainage is good and the water table is at least two feet below the soil line.
When digging rain gardens, the soil is mounded on three sides of the rain garden to create a small berm that catches and holds rainwater. After digging the rain garden, a two by four and carpenters level is used to check that the bottom is level.
Compost should be added to improve drainage and encourage root growth for healthier plants. If needed, rainwater can be directed to the rain garden by the use of shallow swales, downspout extensions, or pvc pipe placed underground.
If rainwater enters the rain garden at a secific spot, it is a good idea to place hardscape such as rocks, bricks or stepping stones to slow the flow of the water and reduce soil erosion at the point of entry.
Plants recommended for rain gardens include those that will tolerate short periods of wet, followed by dry periods when there is no rainfall. Native wildflowers and grasses are most often recommended.
These often have deep or extensive root systems that will absorb more water and aid in the filtering of pollutants. Many of them naturally grow in roadside ditches. Areas that become wet when it rains, but otherwise remain dry.
Some perennials recommended for rain gardens are leadplant (Amorpha), blue false indigo (Baptisia), butterfly milkweed (Asclepias), New England aster, purple prairie clover (Dalea), Joe-pye weed (Eupatorium), prairie coneflower (Ratibida), goldenrod (Solidago) and Rudbeckia.
Ornamental grasses for rain gardens include little bluestem (Schizachyrium), big bluestem (Andropogon), switch grass (Panicum), prairie dropseed (Sporobolus), sedges (Carex) and reeds (Juncus).
The maintenance of rain gardens is the same as most gardens or landscape beds. Weeding, mulching, some irrigation during dry spells, and general plant maintenance such as deadheading spent flowers and plant division.
As with any garden or landscape bed, it is important that lawn irrigation systems do not water rain garden. The soil would remain too wet for too long and most plants will perform poorly.
With rain gardens, especially new ones, they should be monitored during and after rain storms to make sure water is spreading evenly across them and draining in an adequate amount of time. The garden needs to be checked for sediment build-up and erosion of the berms.
If you would like more information on installing a rain garden, check out the following link.
Wisconsin Department of Natural Resources- Rain Gardens Infiltrating Wisconsin!, http://www.dnr.state.wi.us/org/water/wm/nps/rg/
Information source: Rain Gardens – A How-To Manual For Homeowners. University of Wisconsin-Extension and Wisconsin Department of Natural Resources.
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