Preparing an Emergency Safe Drinking Water Supply Before a Storm

Preparing an Emergency Safe Drinking Water Supply Before a Storm

Prepare an emergency drinking water supply for your household before a storm hits. Image: Tyler Jones, UF/IFAS.

Storm season is upon us. During a natural disaster, normal drinking water supplies can quickly become contaminated. To be prepared, collect and store a safe drinking water supply for your household before a storm arrives.

How much water should be stored?

  • Store enough clean water for everyone in the household to use 1 to 1.5 gallons per day for drinking and personal hygiene (small amounts for things like brushing teeth). Increase this amount if there are children, sick people, and/or nursing mothers in the home. If you have pets, store a quart to a gallon per pet per day, depending on its size.
  • Store a minimum 3-day supply of drinking water. If you have the space for it, consider storing up to a two-week supply.
  • For example, a four-person household requiring 1.5 gallons per person per day for 3 days would need to store 18 gallons: 4 people × 1.5 gallons per person × 3 days = 18 gallons. Don’t forget to include additional water for pets!

What containers can be used to store drinking water?

Store drinking water in thoroughly washed food-grade safe containers, which include food-grade plastic, glass containers, and enamel-lined metal containers, all with tight-fitting lids. These materials will not transfer harmful chemicals into the water or food they contain.

More specific examples include containers previously used to store beverages, like 2-liter soft drink bottles, juice bottles or containers made specifically to hold drinking water. Avoid plastic milk jugs if possible because they are difficult to clean. If you are going to purchase a container to store water, make sure it is labeled food-grade or food-safe.

As an extra safety measure, sanitize containers with a solution of 1 teaspoon of non-scented household bleach per quart of water (4 teaspoons per gallon of water). Use bleach that contains 5%–9% sodium hypochlorite. Add the solution to the container, close tightly and shake well, making sure that the bleach solution touches all the internal surfaces. Let the container sit for 30 seconds and pour the solution out. You can let the container air dry before use or rinse it thoroughly with clean water.

Best practices when storing drinking water

  • Store water away from direct sunlight, in a cool dark place if possible. Heat and light can slowly damage plastic containers and can eventually lead to leaks.
  • Make sure caps or lids are tightly secured.
  • Store smaller containers in a freezer. You can use them to help keep food cool in the refrigerator if the power goes out during a storm.
  • Keep water containers away from toxic substances (such as gasoline, kerosene, or pesticides). Vapors from these substances can penetrate plastic.
  • When possible, use water from opened containers in one or two days if they can’t be refrigerated.
  • Although properly stored public-supply water should have an indefinite shelf life, replace every 6-12 months for best taste.

More information on preparing an emergency drinking water supply can be found on the CDC website  and in the EDIS Publication ‘Preparing and Storing an Emergency Safe Drinking Water Supply

Septic System Do’s and Dont’s After a Flood


Special care needs to be taken with your septic system after flooding. Image: B. White NASA. Public Domain

During and after floods or heavy rains, the soil in your septic system drainfield can become waterlogged. For your septic system to treat wastewater, water needs to drain freely in the drainfield. Special care needs to be taken with your septic system under flood conditions.

A conventional septic system is made up of a septic tank (a watertight container buried in the gound) and a drainfield. Image: Soil and Water Science Lab UF/IFAS GREC.

A conventional septic system is made up of a septic tank and a drainfield or leach field. Wastewater flows from the septic tank into the drainfield, which is typically made up of a distribution box (to ensure the wastewater is distributed evenly) and a series of trenches or a single bed with perforated PVC pipes. Wastewater seeps from these pipes into the surrounding soil. Most wastewater treatment occurs in the drainfield soil. When working properly, many contaminants, like harmful bacteria, are removed through die-off, filtering and interaction with soil surfaces.

What should you do if flooding occurs?

The U.S. Environmental Protection Agency (EPA) offers these guidelines:

  1. Relieve pressure on the septic system by using it less or not at all until floodwaters recede and the soil has drained. Under flooded conditions, wastewater can’t drain in the drainfield and can back up in your septic system and household drains. Clean up floodwater in the house without dumping it into the sinks or toilet. This adds additional water that an already saturated drainfield won’t be able to process. Remember that in most homes all water sent down the pipes goes into the septic system.
  2. Avoid digging around the septic tank and drainfield while the soil is waterlogged. Don’t drive vehicles or equipment over the drainfield. Saturated soil is very susceptible to compaction. By working on your septic system while the soil is still wet, you can compact the soil in your drainfield, and water won’t be able to drain properly. This reduces the drainfield’s ability to treat wastewater and leads to system failure.
  3. Don’t open or pump the septic tank if the soil is waterlogged. Silt and mud can get into the tank if it is opened and can end up in the drainfield, reducing its drainage capability. Pumping under these conditions can cause a tank to float or ‘pop out’ of the ground, and can damage inlet and outlet pipes.
  4. If you suspect your system has been damaged, have the tank inspected and serviced by a professional. How can you tell if your system is damaged? Signs include: settling, wastewater backs up into household drains, the soil in the drainfield remains soggy and never fully drains, a foul odor persists around the tank and drainfield.
  5. Keep rainwater drainage systems away from the septic drainfield. As a preventive measure, make sure that water from roof gutters doesn’t drain towards or into your septic drainfield. This adds an additional source of water that the drainfield has to process.
  6. Have your private well water tested if your septic system or well were flooded or damaged in any way. Your well water may not be safe to drink or use for household purposes (making ice, cooking, brushing teeth or bathing). You need to have it tested by the Health Department or other certified laboratory for total coliform bacteria and coli to ensure it is safe to use.

For more information on septic system maintenance after flooding, go to:

More information on having your well water tested can be found at:

More Information on conventional and advanced treatment septic systems can be found on the UF/IFAS Septic System website

After Flooding, Test Your Well Water

After Flooding, Test Your Well Water

If your private well was damaged or flooded due to hurricane or other heavy storm activity, your well water may not be safe to drink. Well water should not be used for drinking, cooking purposes, making ice, brushing teeth or bathing until it is tested by a certified laboratory for total coliform bacteria and E. coli.

Residents should use bottled, boiled or treated water until their well water has been tested and deemed safe.

  • Boiling: To make water safe for drinking, cooking or washing, bring it to a rolling boil for at least one minute to kill organisms and then allow it to cool.
  • Disinfecting with bleach: If boiling isn’t possible, add 1/8 of a teaspoon or about 8 drops of fresh unscented household bleach (4 to 6% active ingredient) per gallon of water. Stir well and let stand for 30 minutes. If the water is cloudy after 30 minutes, repeat the procedure once.
  • Keep treated or boiled water in a closed container to prevent contamination

Use bottled water for mixing infant formula.

Where can you have your well water tested?

Contact your county health department for information on how to have your well water tested. Image: F. Alvarado Arce

Most county health departments accept water samples for testing. Contact your local department for information about what to have your water tested for (they may recommend more than just bacteria), and how to collect and submit the sample.

Contact information for Florida Health Departments can be found here: County Health Departments – Location Finder

You can also submit samples to a certified commercial lab near you. Contact information for commercial laboratories that are certified by the Florida Department of Health are found here: Laboratories certified by FDOH

This site includes county health department labs, commercial labs as well as university labs. You can search by county.

What should you do if your well water sample tests positive for bacteria?

The Florida Department of Health recommends well disinfection if water samples test positive for total coliform bacteria or for both total coliform and E. coli, a type of fecal coliform bacteria.

You can hire a local licensed well operator to disinfect your well, or if you feel comfortable, you can shock chlorinate the well yourself.

You can find information on how to shock chlorinate your well at:

After well disinfection, you need to have your well water re-tested to make sure it is safe to use. If it tests positive again for total coliform bacteria or both total coliform and E. coli call a licensed well operator to have the well inspected to get to the root of the problem.

Well pump and electrical system care

If the pump and/or electrical system have been underwater and are not designed to be used underwater, do not turn on the pump. There is a potential for electrical shock or damage to the well or pump. Stay away from the well pump while flooded to avoid electric shock.

Once the floodwaters have receded and the pump and electrical system have dried, a qualified electrician, well operator/driller or pump installer should check the wiring system and other well components.

Remember: You should have your well water tested at any time when:

  • A flood occurred and your well was affected
  • The color, taste or odor of your well water changes or if you suspect that someone became sick after drinking your well water.
  • A new well is drilled or if you have had maintenance done on your existing well
  • There has been any type of chemical spill (pesticides, fuel, etc.) into or near your well

The Florida Department of Health maintains an excellent website with many resources for private well users: FDOH Private Well Testing and other Reosurces which includes information on potential contaminants and how to maintain your well to ensure the quality of your well water.

Hurricanes and floods: Meeting the resource needs of private well owners

Flooding along the South Prong of the Black Creek River in Clay County on September 13, 2017. Photo credit: Tim Donovan, Florida Fish and Wildlife Conservation Commission (FWC).

As hurricane season is upon us again, I wanted to share the results of work that UF/IFAS Extension staff did with collaborators from Virginia Tech and Texas A&M University to help private well owners impacted by Hurricanes Irma and Harvey last year. This work highlights just how important it is to be prepared for this year’s hurricane season and to make sure that if flooding does occur, those that depend on private wells for household use take the proper precautions to ensure the safety of their drinking water.

About 2.5 million Floridians (approximately 12% of the population) rely on private wells for home consumption. While public water systems are regulated by the U.S. Environmental Protection Agency to ensure safe drinking water, private wells are not regulated. Private well users are responsible for ensuring the safety of their own water.

Hurricanes Irma and Harvey

In response to widespread damage and flooding caused by Hurricane Harvey in Texas and Irma in Florida in August and September 2017, Virginia Polytechnic Institute and State University (VT) received a Rapid Research Response Grant from the National Science Foundation to offer free well water testing to homeowners impacted by flooding.

They partnered with Texas A&M AgriLife Extension’s Well Owner Network (run by Diane Boellstorff and Drew Gholson) and us, at UF/IFAS Extension to provide this service. The effort at VT was led by members of Marc Edward’s lab in the Civil Engineering Department: Kelsey Pieper, Kristine Mapili, William Rhoads, and Greg House.

VT made 1,200 sampling kits available in Texas and 500 in Florida, and offered free analysis for total coliform bacteria and E. coli as well as other parameters, including nitrate, lead, arsenic, iron, chloride, sodium, manganese, copper, fluoride, sulfate, and hardness (calcium and magnesium). Homeowners were also asked to complete a needs assessment questionnaire regarding their well system characteristics, knowledge of proper maintenance and testing, perceptions of the safety of their water and how to best engage them in future outreach and education efforts.

Response in the aftermath of Irma

Although the sampling kits were available, a major challenge in the wake of Irma was getting the word out as counties were just beginning to assess damage and many areas were without power. We coordinated the sampling effort out of Quincy, Florida, where I am based, and spread the word to extension agents in the rest of the state primarily through a group texting app, by telephone and by word of mouth. Extension agents in 6 affected counties (Lee, Pasco, Sarasota, Marion, Clay and Putnam) responded with a need for sample kits, and they in turn advertised sampling to their residents through press releases.

Residents picked up sampling kits and returned water samples and surveys on specified days and the samples were shipped overnight and analyzed at VT, in Blacksburg, VA. Anyone from nearby counties was welcome to submit samples as well. This effort complemented free well water sampling offered by multiple county health departments throughout the state.

In all, 179 water samples from Florida were analyzed at VT and results of the bacterial analysis are shown in the table below. Of 154 valid samples, 58 (38%) tested positive for total coliform bacteria, and 3 (2%) tested positive for E. coli. Results of the inorganic parameters and the needs assessment questionnaire are still being analyzed.

Table 1. Bacterial analysis of private wells in Florida after Hurricane Irma.

County Number of samples (n) Positive for total coliform (n) Positive total coliform (%) Positive for E. coli (n) Positive for E. coli (%)
Citrus 1 0 0% 0 0%
Clay 13 5 38% 0 0%
Hernando 2 1 50% 0 0%
Hillsborough 1 1 100% 0 0%
Marion 19 5 26% 1 5%
Monroe 1 0 0% 0 0%
Pasco 40 19 48% 1 3%
Putnam 61 19 31% 0 0%
Sarasota 16 8 50% 1 6%
Overall 154 58 38% 3 2%

Of 630 samples analyzed in Texas over the course of 7 weeks post-Hurricane Harvey, 293 samples (47% of wells) tested positive for total coliform bacteria and 75 samples (2%) tested positive for E. coli.

What to do if pathogens are found

Following Florida Department of Health (FDOH) guidelines, we recommended well disinfection to residents whose samples tested positive for total coliform bacteria, or both total coliform and E. coli. This is generally done through shock chlorination by either hiring a well operator or by doing it yourself. The FDOH website provides information on potential contaminants, how to shock chlorinate a well and how to maintain your well to ensure the quality of your well water (http://www.floridahealth.gov/environmental-health/private-well-testing/index.html).

UF/IFAS extension agents that led the sampling efforts in their respective counties were: Roy Beckford – Lee County; Brad Burbaugh – Clay County; Whitney Elmore – Pasco County; Sharon Treen – Putnam and Flagler Counties; Abbey Tyrna – Sarasota County and Yilin Zhuang – Marion County.

We at IFAS Extension are working on using results from this sampling effort and the needs assessment questionnaire filled out by residents to develop the UF/IFAS Florida Well Owner Network. Our goal is to provide residents with educational materials and classes to address gaps in knowledge regarding well maintenance, the importance of testing and recommended treatments when pathogens and other contaminants are present.

Remember: Get your well water tested if flooding occurs

It’s important to remember that if any flooding occurs on your property that affects your well and/or septic system, you should have your well water tested in a certified laboratory for pathogens (total coliform bacteria and E. coli) and any other parameters your local health department may recommend.

Most county health departments accept samples for water testing. You can also submit samples to a certified commercial lab near you. Contact your county health department for information about what to have your water tested for and how to take and submit the sample.

Contact information for county health departments can be found online at: http://www.floridahealth.gov/programs-and-services/county-health-departments/find-a-county-health-department/index.html

You can search for laboratories near you certified by FDOH here: https://fldeploc.dep.state.fl.us/aams/loc_search.asp This includes county health department labs as well as commercial labs, university labs and others.

You should also have your well water tested at any time when:

  • The color, taste or odor of your well water changes or if you suspect that someone became sick after drinking your well water
  • A new well is drilled or if you have had maintenance done on your existing well

Testing well water once a year is good practice to ensure the safety of your household’s drinking water.

Septic systems: What should you do when a flood occurs?

Special care needs to be taken with a septic system after a flood or heavy rains. Photo credit: Flooding in Deltona, FL after Hurricane Irma. P. Lynch/FEMA

Approximately 30% of Florida’s population relies on septic systems, or onsite sewage treatment and disposal systems (OSTDS), to treat and dispose of household wastewater. This includes all water from bathrooms and kitchens, and laundry machines.

When properly maintained, septic systems can last 25-30 years, and maintenance costs are relatively low. In a nutshell, the most important things you can do to maintain your system is to make sure nothing but toilet paper is flushed down toilets, reduce the amount of oils and fats that go down your kitchen sink, and have the system pumped every 3-5 years, depending on the size of your tank and number of people in your household.

During floods or heavy rains, the soil around the septic tank and in the drain field become saturated, or water-logged, and the effluent from the septic tank can’t properly drain though the soil. Special care needs to be taken with your septic system during and after a flood or heavy rains.

 

Image credit: wfeiden CC by SA 2.0

How does a traditional septic system work?

The most common type of OSTDS is a conventional septic system, made up of (1) a septic tank (above), which is a watertight container buried in the ground and (2) a drain field, or leach field. The effluent (liquid wastewater) from the tank flows into the drain field, which is usually a series of buried perforated pipes. The septic tank’s job is to separate out solids (which settle on the bottom as sludge), from oils and grease, which float to the top and form a scum layer. Bacteria break down the solids (the organic matter) in the tank. The effluent, which is in the middle layer of the tank, flows out of the tank and into the drain field where it then percolates down through the ground.

During floods or heavy rains, the soil around the septic tank and in the drain field become saturated, or water-logged, and the effluent from the septic tank can’t properly drain though the soil. Special care needs to be taken with your septic system during and after a flood or heavy rains.

What should you do after flooding occurs?

  • Relieve pressure on the septic system by using it less or not at all until floodwaters recede and the soil has drained. For your septic system to work properly, water needs to drain freely in the drain field. Under flooded conditions, water can’t drain properly and can back up in your system. Remember that in most homes all water sent down the pipes goes into the septic system. Clean up floodwater in the house without dumping it into the sinks or toilet.
  • Avoid digging around the septic tank and drain field while the soil is water logged. Don’t drive heavy vehicles or equipment over the drain field. By using heavy equipment or working under water-logged conditions, you can compact the soil in your drain field, and water won’t be able to drain properly.
  • Don’t open or pump out the septic tank if the soil is still saturated. Silt and mud can get into the tank if it is opened, and can end up in the drain field, reducing its drainage capability. Pumping under these conditions can also cause a tank to pop out of the ground. 
  • If you suspect your system has been damage, have the tank inspected and serviced by a professional. How can you tell if your system is damaged? Signs include: settling, wastewater backs up into household drains, the soil in the drain field remains soggy and never fully drains, and/or a foul odor persists around the tank and drain field.
  • Keep rainwater drainage systems away from the septic drain field. As a preventive measure, make sure that water from roof gutters doesn’t drain into your septic drain field – this adds an additional source of water that the drain field has to manage.

More information on septic system maintenance after flooding can be found on the EPA website publication https://www.epa.gov/ground-water-and-drinking-water/septic-systems-what-do-after-flood

By taking special care with your septic system after flooding, you can contribute to the health of your household, community and environment.