Preparing an Emergency Safe Drinking Water Supply Before and After a Storm

Preparing an Emergency Safe Drinking Water Supply Before and After a Storm

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

Hurricane season is just around the corner. During a natural disaster, drinking water supplies can quickly become contaminated. To be prepared, store a safe drinking water supply before a storm arrives. If you are unable to store enough water before a storm, it’s important to know how to make water safe to consume in an emergency.

Before a storm: 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.
  • 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: 4 people × 1.5 gallons per person × 3 days = 18 gallons. Don’t forget to include additional water for pets! Store a quart to a gallon per pet per day,depending on their size.
Examples of 3 and 5 gallon food grade jugs for storing water. Image: A. Albertin
What containers can be used to store drinking water?

Store drinking water in thoroughly washed food grade safe containers that are durable and unbreakable such as food grade plastic and enamel-lined metal containers with tight-fitting lids. These materials will not transfer harmful chemicals into the water or food they contain.

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. Make 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 where toxic substances (such as gasoline, kerosene, or pesticides) are stored. 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.

More information on preparing an emergency drinking water supply can be found at the Centers for Disease Control (CDC) and in the EDIS Publication Preparing and Storing an Emergency Safe Drinking Water Supply

After a storm: Ensuring a safe drinking water supply

If a boil water notice has been issued in the area you live or you suspect your water supply may be contaminated, don’t consume it. Do not use it for drinking, preparing baby formula or food, making ice (if you have electricity), washing dishes, or brushing your teeth. Don’t swallow water when bathing. If you have any open cuts or wounds, do not use it for bathing. Instead, use your own clean, stored water supply or use bottled water.  

If you don’t have access to clean water, you can boil, disinfect, and filter your water during an emergency to make it safe to drink.  But, if your water is contaminated by fuel or toxic chemicals, boiling or disinfection won’t make it safe to drink. In these cases, it’s important to call your local health department for guidance and use bottled water instead.

Boiling water is the most effective way to destroy pathogens in water including viruses, bacteria, and parasites such as Cryptosporiduim and Giardia. If the water is cloudy or murky, let it settle and filter it through a clean cloth or coffee filter before boiling.

  • Once water begins boiling, continue to boil it for at least one minute.
  • Let the water cool and transfer it to a clean, food-grade container with a tight lid.
  • You can improve the taste of boiled water by aerating it (transfer water back and forth from one clean container to another) or you can add a pinch of salt for each quart of boiled water.

Disinfecting water will kill most viruses and bacteria, but it’s not as effective in killing parasites (like Giardia and Cryptosporidium) as boiling. Disinfect water by using the following amounts of household chlorine bleach (5%-9% sodium hypochlorite) and water. Do not use ‘splashless’ bleach or scented bleach. If the water is cloudy or murky, filter through a clean cloth or coffee filter before disinfecting. If water remains cloudy, double the amount of recommended chlorine bleach.

Amount of waterAmount of chlorine bleach  (5-9% sodium hypochlorite)
 Clear water   Cloudy water
1 quart2 drops4 drops
1 gallon8 drops16 drops
5 gallons½ teaspoon1 teaspoon

After mixing in the bleach, let the water stand for 30 minutes. If the water is still cloudy after 30 minutes, repeat the chlorination procedure once.

You can also use chlorine dioxide tablets, or iodine tablets to disinfect water. Follow the manufacturer’s instructions for disinfection.

Filtering water – According to the CDC, many filtration systems can remove parasites like Giardia and Cryptosporidium if the absolute pore size is 1 micron or smaller. This does not filter out viruses or many bacteria. When choosing a filter, it’s important to carefully read the manufacturer’s instructions to understand what the system is effective against. The CDC recommends adding a disinfectant to the filtered water (chlorine, iodine, or chlorine dioxide tablets) to kill most viruses and bacteria. Follow the manufacturer’s instructions for disinfection.

More detailed information about making water safe to drink can be found at the CDC, FEMA and the US Environmental Protection Agency (EPA).

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

What is the La Nina? did it impact this hurricane season?

What is the La Nina? did it impact this hurricane season?

I think we can all agree it has been one crazy hurricane season.  We have gone through the entire alphabet, and much of the Greek alphabet, naming storms – a record 30.  Here in Pensacola we had Sally, but we had to prepare for many others that were wobbling around out there.  It seemed this year the computer models were struggling predicting landfall locations.  The “spaghetti” paths of the recent Eta were all over the Gulf.   So, what is going on?  It probably has to do with a warmer Gulf but there has to be more to it than that.  Some have mentioned that it has been a La Nina year, and that the Gulf is more active during such years.  Fair enough… what is the La Nina?

 

It is the opposite of the El Nino – a term more people have heard of.  Okay… what is the El Nino?

The red indicates warm water temperatures. Notice the warm temps in the eastern Pacific – not normal.
Graphic: NOAA

 

 

The El Nino is a warming trend observed in the eastern Pacific Ocean every 2-7 years around Christmas time.  El Nino… “the child”.  There are records of this event going back over a century.  It was first noticed by Peruvian fishermen, who fish some of the most productive waters on the planet.  These productive waters are fueled by the cold Humboldt Current and an upwelling bringing nutrient rich cold waters from the seafloor.  When the El Nino occurs the Humboldt Current warms and “caps” the upwelling from reaching the surface where the food chain can benefit.  The fish move away, and the fishermen notice it.  When people began to colonize southern California, and began fishing for tuna and sardines, they noticed the same thing.  The El Nino moved north of the equator just as it moves south of it. 

 

To better understand this, we will need to know a little about the ocean currents. 

The world rotates on its axis every 24 hours – there, we are off to a good start. 

The sun’s rays hit the earth more directly in the equatorial part of the planet, making it warmer there. 

The cold polar water is more dense and sinks.  The warmer equatorial waters move across the surface of the ocean to fill the void left by the sinking polar water.  But it does not move in a straight line to that point.  The world is turning remember, and this cause the moving water to bend in a curved pattern.  The equatorial water moves west by northwest, warming more as it moves.  This is the equatorial current.  When it reaches Indonesia it is a balmy 80F+ (or so).  This is the land of palm trees and coral reefs – “Bali-Hai”. 

The equatorial currents of the Pacific.
Image: NOAA

The water now moves north towards Japan and Korea before heading towards Alaska.  Here it is called the Kuroshio Current and here it slowly begins to lose its warmth.  As it slides beneath Alaska heading for Canada it is called the North Pacific Current, and then becomes the California Current as it passes the western United States heading back towards the equator.  Here the water is much cooler (60-70F).  There are no coral reefs, but you do find palm trees in southern California.  This coast is also bathed with an upwelling and supports a rich fishery.  

 

The southern Pacific is the same – but the current names are different.  The equatorial current heads west reaching Indonesia and heads south to Australia where they call it the East Australian Current (the EAC of Finding Nemo fame).  This is the home of the Great Barrier Reef.  The currents circle near Antarctica, become colder, and head north along South America as the Humboldt Current (also known as the Peru Current). 

 

Now imagine this…

Imagine the warm equatorial water near Indonesia begins to slide back towards California and Central America.  Imagine this warm water layer then heads north and south to the coasts of California and Peru.  This warm water caps the upwelling and the fish leave – near Christmas time – the El Nino.  Bad times for the fishing fleet. 

Commercial fishing in the California Current.
Photo: NOAA

The atmosphere responds to these ocean temperature shifts.  Normally, the cooler waters reaching the equator from California and Peru move westward forming the equatorial current.  This cool water helps form east winds that move across westward as well.  Known as the Trade Winds, sailors have used them for centuries to reach “good trading locations”.  They are steady and dependable… unless it is an El Nino year.  During El Nino the warmer ocean slows the strength of these winds.  They actually move eastward across Central America and impact the Gulf of Mexico.  During El Nino years these eastward moving Pacific winds push hurricanes out of the Gulf into the Atlantic.  These are the hurricane seasons when Bermuda is hit frequently. 

 

La Nina is the opposite.  The Pacific waters moving into the equatorial area from California and Peru are colder than normal.  These colder waters move faster and farther across the equatorial waters of the Pacific increasing the Trade Winds moving west… not east.  With these Trade Winds moving in the direction they should, even stronger than normal, hurricanes are “sucked” into the Gulf of Mexico.  La Nina seasons are very busy hurricane seasons for us.  And you guessed it, it is a La Nina year.  La Nina usually follows the El Nino and we can sometimes experience them for two seasons, but 12 months is typical. 

 

The thing is La Nina’s have been occurring for centuries.  We have certainly had hurricane seasons that were busier than normal but not to the extent we saw this year.  You have to look at climate change in general, and other atmospheric conditions that could influence this.  I am sure the meteorologists and climatologists are as interested in what happened (is happening) this year as we are. 

 

Hopefully we will not see another season like this for some time. 

Happy Thanksgiving. 

Climate Change and Future Hurricanes

Climate Change and Future Hurricanes

A living shoreline project was implemented on this bay in Santa Rosa County to try and prevent further erosion. Photo credit: Carrie Stevenson, UF IFAS Extension

We have reached that time of year when the Atlantic starts cranking out storms, and they will continue to roll out as the dog days of summer progress. Over the last decade, many experts have speculated on how climate change and sea level rise might impact hurricanes in the Gulf of Mexico. Two big issues are coastal erosion and flooding from storm surge and rainfall.

Those who live on the water or frequently visit area shorelines have probably noticed coastal erosion. While a natural part of a coastal ecosystem–and often exacerbated by heavy boat traffic–rising seas can also cause erosion. Sea level rise moves water slowly inland and washes away the roots of grasses and trees that once held the shoreline in place. Buildings and roads close to the water are impacted as well, with “sunny day flooding” on the roads and under pilings in many south Florida cities where water has moved in to stay. Large scale beach renourishment projects, living shorelines, and even road relocations (like the one at Ft. Pickens on Pensacola Beach) are all ways that local officials and property owners can respond to rising seas. However, these efforts always come with a big price tag. When that “line in the sand” is drawn beyond government and household budgets, there will come a point when we can no longer support protection of highly vulnerable coastal infrastructure. The closer a building is physically located to the water (whether built there intentionally or reached by rising seas), the greater the likelihood a hurricane will cause flooding damage from dangerous storm surge. Storm surge and heavy flooding cause 75% of the deaths in any given hurricane.

During a recent webinar, the appropriately named Dr. Chris Landsea of the National Hurricane Center answered several frequently asked questions on the impacts of global warming on hurricanes. Some of the predictions are surprising based on assumptions that have been put out in the media. He made a disclaimer that these are his predictions based on years of expertise and data analysis, and not an official proclamation by the National Hurricane Center. Following are a few of the points he made during his talk.

Dr. Chris Landsea of the National Hurricane Center recently met with floodplain managers around the Gulf Coast to discuss hurricanes.

Question: Will hurricanes get stronger based on increased temperatures?

Answer: The world average temperature has gone up 1.5 degrees Fahrenheit in the past 100 years. Based on data and computer modeling from the NOAA Geophysics Lab, typical hurricane wind intensity will increase slightly, by 3%. In this example, a storm with 100 mph average winds would be 103 mph by the end of the 21st century.

Question: Will we experience more tropical storms as the climate changes?

Answer: Dr. Landsea does not expect more tropical storms as the temperature increases. In fact, frequency may drop very slightly. While there may be more heat energy for hurricanes to feed on, the surrounding conditions will make it tougher for a storm to form. Those conditions may be atmospheric or include a vertical wind shear that tears up the storm.

Question: How will global warming affect rainfall during hurricanes?

Answer: Models and recent experience show that rainfall will increase by 10-20% during tropical storms. Global warming increases the amount of moisture in the atmosphere, and a hurricane can recycle this water into a constant loop of rainfall. Hurricane Harvey in Texas was one example of this situation, during which nearly 8 feet of rainfall fell, flooding neighborhoods. One of the aphorisms of climate change is “wet places get wetter, and dry places get drier.”

Dr. Landsea’s full presentation can be found online here, if you are interested in learning more. Keep in mind that these predictions can change based on land use, atmospheric carbon levels, and human practice change. For more on the work UF IFAS is doing on climate, visit this Florida Sea Grant Climate page.

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.