Flood Protection Information

Know your flood hazard.

FEMA publishes maps showing flood hazard areas and the degree of risk in those areas. These maps are on file at your local library or the Parish Administrative Offices, 1801 W. Airline Highway in LaPlace, or online here. Check with the Parish Planning & Zoning Department (985) 651-5565, to see if your property is in a special flood hazard zone.

Did you know that your property may be located in a flood prone area? You're not alone. Over 87% of St. John the Baptist Parish has been designated by the Federal Emergency Management Agency (FEMA) as a special flood hazard area. Special Flood Hazard Areas are designated as Zones "A" and "V". Zone "A" is referred to as the "100 year floodplain" meaning that this is an area that will be flooded on the average of once every 100 years, with a 1% chance of being flooded in any given year. Put another way, there is a 30% chance of your property being flooded over the life of a 30-year mortgage.

Flood zone "V" is an area where wave action is likely to occur over and above the flooding. The areas along the shore of Lakes Maurepas, Pontchartrain, and Lac Des Allemands are designated as "V" zones. Localized flooding can occur anywhere in the Parish, even outside of a “flood zone” or the special flood hazard area when isolated rainstorms drop large amounts of rain in relatively short periods of time. 

Protect yourself from floodwaters

Turn around, don’t drown!

If you see floodwater on roads, walkways, bridges, or on the ground, do not to attempt to cross. The depth of the water is not always obvious and water can hide damage or dangerous debris. Be aware of areas where floodwaters have receded and watch out for debris.

Each year, more deaths occur due to flooding than from any other thunderstorm related hazard. The Centers for Disease Control and Prevention report that over half of all flood-related drownings occur when a vehicle is driven into hazardous flood water. The next highest percentage of flood-related deaths is due to walking into or near flood waters. People underestimate the force and power of water. Many of the deaths occur in cars swept downstream. Many of these drownings are preventable. Never drive around the barriers blocking a flooded road. The road may have collapsed under that water.  A mere 6 inches of fast-moving flood water can knock over an adult. It takes just 12 inches of rushing water to carry away most cars and just 2 feet of rushing water can carry away SUVs and trucks. It is NEVER safe to drive or walk into flood waters.

Protect your property from flooding

In St. John the Baptist Parish, flooding can occur during any season of the year. Your property may be in a Special Flood Hazard Area as determined by the Federal Emergency Management Agency (FEMA).

The principal sources of flooding in St. John the Baptist Parish are rain and Lakes Pontchartrain, Maurepas, and Lac Des Allemands.

Floodwater collects in low areas and land prone to subsidence or sinking. The low, flat ground provides little gravity drainage in a severe event.

The Parish drainage system does a remarkable job, but when the ground is saturated, and heavy rain falls quickly, the system can be overwhelmed, and flooding can result.

There are many things you can do to an existing building to minimize or eliminate the potential for flood damage.

Sandbags, plywood, plastic sheeting, and lumber can be used to protect property temporarily.

(Remember, sandbags should not be stacked directly against the outer walls of a building since wet bags may create added pressure on the foundation).

Permanent floodproofing measures for flood prone structures are preferable to temporary ones. These permanent retrofitting methods include elevating the structure, building floodwalls and closures, and protecting utilities.

A booklet called Flood Proofing Techniques, Programs, and References (1991, 23pp) is free from the US. Corps of Engineers, National Flood Proofing Committee, Attn.: CECW-PF, 20 Massachusetts Avenue, Washington DC 20314-1000. You can also get information on retrofitting from the main parish public library. In addition to retrofitting booklets, the main library has publications on flood insurance, flood protection, and floodplain management.

Get more info on the West Shore Lake Pontchartrain Levee here.

USACE levee information.

Flood Warning

In a flood-prone area like St. John the Baptist Parish, you'll often hear these two terms: “Watch” and “Warning.” A Flood Watch means flooding is possible. A Flash Flood Watch means a flash flood, which can happen very fast with little warning, is possible. A Flood Warning means a flood is occurring or will occur soon; the flood may take several hours to develop. A Flash Flood Warning means a flash flood is occurring or will happen very soon; you should find safety immediately.

Watches and warnings will be broadcast on radio and television. Listen to local stations for news, information, and instructions.

One radio station, the National Oceanic and Atmospheric Administration (NOAA) Weather Radio, broadcasts weather information at 162.55 MHz 24 hours a day from National Weather Service Offices in Louisiana. To receive the NOAA broadcasts, you must have a weather radio or conventional AM/FM radio with a weather band.

  • Tune to WWL 870 AM radio.
  • If you have cable TV, bulletins will be broadcast on all cable channels
  • If you do not have cable TV, tune to WWL Channel 4, WDSU Channel 6, WVUE Channel 8, or WGNO Channel 38 to obtain timely civil defense reports or National Weather Service bulletins
  • Click here to sign up for emergency alerts through St. John the Baptist Parish

Protect natural floodplain functions.

Floodplains are lowland areas adjacent to lakes, wetlands and rivers that are covered by water during a flood. The most easily seen function of a floodplain is its ability to carry and store floodwaters. Undeveloped floodplain also provides many other natural and economic resource benefits. They have high biological diversity and productivity. Floodplain vegetation and soils serve as water filters, intercepting surface water runoff before it reaches nearby lakes. This process aids in the removal of excess nutrients, pollutants and sediments from the water and helps reduce the need for costly clean-ups and sediment removal. The floodplain also serves as a natural reservoir, temporarily holding flood waters and slowly releasing them, reducing the extent and frequency of flooding.

Flood Safety

Keep alert to rapidly changing weather and to news bulletins.

Learn the safest route from your home or business to higher, safer ground, but stay tuned to reports of changing flood conditions.

If emergency officials tell you to evacuate or leave your home, go immediately to a safe shelter, hotel, or relative's or friend's home. Turn off all utilities at the main switch - BUT ONLY IF TIME PERMITS. Do not touch any electrical equipment unless it is in a dry area. Every source of electricity can be dangerous during and after flooding.

If you are caught in a building by suddenly rising water, move to the second floor or the roof (you may need a tool on hand to break through to the roof. Take drinking water, a flashlight and a portable radio with you. Wait for help.

If your car stalls in a flooded area, abandon it as soon as possible. Floodwater can sweep a car away.

Swimming or playing in or near floodwater is life threatening. Drainage ditches and canals carry fast-moving floodwater and are extremely dangerous. Explain this to your children.

Remember, FLOODS ARE DECEPTIVE. Try to avoid flooded areas, and don't attempt to walk through floodwater that is more than knee deep. If you are unsure of the depth of water, TURN AROUND, DON’T DROWN.

Insure your property for your flood hazard

Purchase flood insurance! Most standard homeowner's insurance policies do not cover losses from flooding. Renters can also buy policies to protect their personal property.

You are eligible for flood insurance because St. John the Baptist Parish participates in the National Flood Insurance Program, administered by FEMA. If the FEMA flood maps show that a property is in a Special Flood Hazard Area, which includes all A and V Zones, flood insurance is required by law in order to get federally secured financing to buy, build, or improve structures on that property.

Your insurance agent will help you decide how much coverage you need. For more information, talk to your insurance agent or call FEMA at 1-800-638-6620.

Once you've purchased flood insurance, keep your policy and an itemized list of your furnishings, clothing, and valuables in a safe place, such as a safe deposit box. Remember, or carry in your wallet, the name and address of the agent or broker who wrote your policy. Call your agent or broker immediately if you suffer flood damage.

Property Protection

There are many things you can do to an existing building to minimize or eliminate the potential for flood damage.

Sandbags, plywood, plastic sheeting, and lumber can be used to protect property temporarily.

(Remember, sandbags should not be stacked directly against the outer walls of a building since wet bags may create added pressure on the foundation).

Permanent floodproofing measures for flood prone structures are preferable to temporary ones. These permanent retrofitting methods include elevating the structure, building floodwalls and closures, and protecting utilities.

A booklet called Flood Proofing Techniques, Programs, and References (1991, 23pp) is free from the US. Corps of Engineers, National Flood Proofing Committee, Attn.: CECW-PF, 20 Massachusetts Avenue, Washington DC 20314-1000. You can also get information on retrofitting from the main parish public library. In addition to retrofitting booklets, the main library has publications on flood insurance, flood protection, and floodplain management.

Get more info on the West Shore Lake Pontchartrain Levee here.

USACE levee information.

Build responsibly. Check with your local building department before you make a change to your building or yard.

Before proceeding with retrofitting measures, or any construction and development, check with the Parish Planning and Zoning Department at 651-5565 for applicable building codes, permit requirements, and zoning restrictions.

Additionally, if any citizen observes any illegal development in the floodplain, it should be reported immediately to the Community Rating System Coordinator in St. John Parish at 651-5565.

  • Before you do anything - including prepare construction plans, finalize financing, and/or purchase one 2" x 4", call the St. John Parish Inspection Department to find out what regulations apply to you.
  • Explain, precisely, where your property is located and the entirety of your plans for construction. Find out the cost of the permit application fee.
  • Don't hesitate to ask for certain requirements in writing; This protects you and the building official from miscommunication.
  • If you are not sure about a regulation, ask for clarification; and
  • Above all, don't assume that you won't get caught violating the building permit requirement. Code Enforcement and FEMA staff conduct regular inspections to verify that work is not done in the flood zone without a permit.

 

Know the flood history for your area. Buildings in X zones are at risk of flooding.

In Louisiana, six specific types of flooding are of main concern: riverine, flash, ponding, backwater, urban, and coastal.

• Riverine flooding occurs along a river or smaller stream. It is the result of runoff from heavy rainfall or intensive snow or ice melt. The speed with which riverine flood levels rise and fall depends not only on the amount of rainfall, but even more on the capacity of the river itself, as well as the shape and land cover of its drainage basin. The smaller the river, the faster that water levels rise and fall. Thus, the Mississippi River levels rise and fall slowly due to its large capacity. Generally, elongated and intensely developed drainage basins will reach faster peak discharges and faster falls than circular-shaped and forested basins of the same area.

• Flash flooding occurs when locally intense precipitation inundates an area in a short amount of time, resulting in local stream flow and drainage capacity being overwhelmed

• Ponding occurs when concave areas (e.g., parking lots, roads, and clay-lined natural low areas) collect water and are unable to drain.

• Backwater flooding occurs when water slowly rises from a normally unexpected direction where protection has not been provided. A model example is the flooding that occurred in LaPlace during Hurricane Isaac in 2012. Although the town was protected by a levee on the side facing the Mississippi River, floodwaters from Lake Maurepas and Lake Pontchartrain crept into the community on the side of town opposite the Mississippi River.

• Urban flooding is similar to flash flooding but is specific to urbanized areas. It takes place when storm water drainage systems cannot keep pace with heavy precipitation, and water accumulates on the surface. Most urban flooding is caused by slow-moving thunderstorms or torrential rainfall.

 • Coastal flooding can appear similar to any of the other flood types, depending on its cause. It occurs when normally dry coastal land is flooded by seawater but may be caused by direct inundation (when the sea level exceeds the elevation of the land), overtopping of a natural or artificial barrier, or the breaching of a natural or artificial barrier (i.e., when the barrier is broken down by the sea water). Coastal flooding is typically caused by storm surge, tsunamis, or gradual sea level rise.

Historically, in St. John the Baptist Parish, all types of flooding events have historically been observed. 

Substantial Improvements/Damage Requirements

Additions, reconstruction or rehabilitation of your property is subject to National Flood Insurance Policy (NFIP) requirements. Check with the Planning and Zoning Department before proceeding.

The NFIP requires that when the cost of reconstruction, rehabilitation, addition or other improvements to a building equals or exceeds 50% of the fair market value, then the building must meet the same construction requirements as a new building. Substantially damaged buildings must also be brought up to the same standards. A residence or building damaged so that the cost of repair equals or exceeds 50% of the structure's fair market value must also be elevated above the Base Flood Elevation (BFE) in flood zones where BFE's exist. Questions about these requirements may be directed to the Planning & Zoning Dept. at (985) 651-5565

FEMA Elevation Certificates

These certificates are required to determine compliance with Base Flood Elevation (BFE) requirements when building a structure or mitigation of a structure which has been repetitively flooded or substantially damaged. A licensed surveyor must provide this form. Some completed certificates are on file in the Planning & Zoning Dept. for structures built after 2000. Copies of these certificates can be obtained by calling the department at 651-5565 or by visiting the elevation certificate search page here(PDF, 260KB).

For inquiries about the National Flood Insurance Program write:
Federal Emergency Management Agency
Federal Insurance Administration
500 C. Street, S. W.
Washington, DC 20472

Read more about elevation certificates here

Or visit: https://www.floodsmart.gov/

 

Protect yourself and your property. Have a plan for hurricanes, tornadoes, and other natural events.  Know your evacuation zone and route.

Before the Storm

Prepare a personal evacuation plan.

  • Identify ahead of time where you could go if you are told to evacuate.
  • Keep handy the telephone numbers of these places as well as a road map of your locality. You may need to take alternative or unfamiliar routes if major roads are closed.
  • Listen to Parish officials for evacuation instructions. Make sure everyone in your household knows and understands your hurricane evacuation plan.

St. John Parish Assisted Evacuation Plan - Mandatory Evacuation Only

  • St. John Parish will transport residents via school bus to public shelters in North Louisiana. Residents will be registered, and each person will be allowed one suitcase.

Southeast Louisiana Contraflow

  • Contraflow will be a last resort. If used, traffic will flow east on Interstate 10 to the Slidell area, where Interstate 12, Interstate 59, and Interstate 10 meet. From there, people can decide which way they want to go.

 

 

No Dumping - Help keep our water clean for the many plants and animals that live in our rivers, canals, and lakes.

 

 

Dumping in storm drains leads to flooding. Keep storm drains free and clear of debris.

To be habitable, our parish needs to have a drainage system. And keeping the system in tiptop shape is important too. The Public Works Department has a regular program of drainage system maintenance. You can help by clearing the catch basins in front of your property. Also, per section 26:150 of the St. John Parish ordinance, dumping debris in catch basins or in drainage ditches and canals is prohibited and is punishable by a fine. Call the Public Works Department at (985) 652-4815 if you have questions about the parish's drainage system.

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