Sea Grant Initiatives – Archive
    The Next Storm Surge – Archive
    Iberia Parish
    Vermilion Parish
    Lafourche Parish
    Terrebonne Parish





Water Quality

I’ve heard there are oil spills in the parishes to the east and southeast of New Orleans. Is this true?

In the aftermath of Hurricane Katrina there have been at least 10 major to medium oil spills reported (see table below), with the total volume spilled at 8 million gallons. These incidents resulted in the discharge of oil along the Mississippi River from Chalmette to Venice and west to Port Fourchon. Additionally, the U.S. Coast Guard (USCG) estimates that approximately 134 minor spills of less than 10,000 gallons have occurred and are being coordinated at this time. The Louisiana Oil Spill Coordinator’s Office (LOSCO) reported that 3.1 million gallons have been recovered, and 3.7 million gallons have evaporated. By comparison, in America's largest oil spill, the Exxon Valdez dumped 11 million gallons into Alaska's Prince William Sound.

Facility, Location
Murphy Oil, Meraux, La.
Chevron Empire Terminal, Buras, La.
Bass Enterprises, Cox Bay, La.
Shell, Pilottown, La.
Dynegy, Venice, La.
Sundown Energy West, Potash, La.
Sundown Energy East, Potash, La.
Bass Enterprises, Point a la Hache, La.
Shell Pipeline Oil LP, Nairn, La.
Chevron, Port Fourchon, La.

On Nov. 5, 2005, the USCG announced that cleanup efforts had finished at the Shell-Pilottown tank farm. The Pilottown site, where approximately 1.07 million gallons escaped from damaged tanks and pipelines, is the first to complete clean-up. Approximately 950,000 gallons were held in secondary containment and recovered, with the remaining oil either evaporating or dispersing naturally. Clean-up continues at the following sites: Chevron Empire Terminal in Buras; Sundown East and Sundown West, both in Potash; Bass Enterprises Production Co. Cox Bay facility at mile marker 35 on the Mississippi River; Bass Enterprises Production Co. in Pointe a la Hache; Dynegy Venice in Venice.; Murphy Oil in Meraux; and Shell Nairn in Port Sulphur.

The 420,000-gallon spill in Meraux has attracted the most attention, but the largest spill was in the coastal marshes near Empire from a Bass enterprises facility, where two partially-filled storage tanks, both 16 feet high and 290 feet across, were smashed by 28 feet of Katrina flood water and moved 300 feet.

The storm surge from Hurricane Rita damaged containment booms and re-oriented oil spilt during Katrina but resulted in no additional major spills. As of Nov. 15, 2005, no additional major pollution incidents resulted from Hurricane Rita were reported. A few low lying areas remain flooded and assessments were still pending as of Sept. 28, 2005. The USCG reported one medium spill where a 130,000 gallon capacity diesel tank was moved three miles from its original position by Hurricane Rita, resulting in a leak of less than 30,000 gallons.

Additional Sources:
NOAA Office of Response and Restoration’s Incident News
Louisiana Oil Spill Coordinator’s Office (LOSCO)

(Don Davis, Louisiana Applied Oil Spill Research And Development Program and Justin Farrell, Louisiana Sea Grant College Program)) 4-6-06

Back to Top

I have heard that the standing floodwaters in New Orleans are heavily contaminated. Is that true?

To contaminate, by definition, means to make something impure, unclean or polluted, especially by mixing harmful impurities into it or by putting it in contact with something harmful. In order to understand the water quality issue in New Orleans, we must qualify the level of contamination. Most of our surface waters are monitored and managed to meet designated use parameters, such as supporting aquatic life (fish and other aquatic organisms) and swimmable waters, which involve contact with the possibility of ingestion. Obviously, the standards for drinking water are much more stringent. Currently, there are no untreated surface waters, much less floodwaters, with “drinking by humans” as its designated use.
In the case of New Orleans floodwaters, the impurities didn’t get put into Lake Pontchartrain, the lake inundated the city. Just imagine everything in the city which could possibly contaminate water: household cleaning solutions, sewage, automobile fluids and fuel, trash, debris, etc. being picked up by floodwater. However, it’s important to consider the volume of water which inundated the city and how it somewhat diluted the contaminants. Early sample results showed some hot spots, but the majority of samples analyzed for toxins, volatile organics and other contaminants were at or below acceptable levels. The one major concern is the level of E. coli bacteria, which is an indication that the water can be infectious. It is recommended that contact with floodwaters be avoided if at all possible. Fortunately, almost all of the floodwaters have been pumped out of the city, and recent tests indicate the lake has had an amazing ability to assimilate these waters and associated pollutants. (See question on the impacts of floodwaters on Lake Pontchartrain above). For sample results and additional information about the monitoring of floodwaters in New Orleans, visit the Web sites below.

(Kevin Savoie and Brian LeBlanc, Louisiana Sea Grant College Program/LSU AgCenter) 10-6-05

Back to Top

What will be the environmental impact of discharging polluted floodwaters into Lake Pontchartrain?

The Louisiana Department of Environmental Quality (DEQ) and the U.S. Environmental Protection Agency (EPA) are sampling and analyzing floodwater and the water of Lake Pontchartrain. Recently released information indicated very good news for Lake Pontchartrain. DEQ conducted tests of aquatic toxicity on flood waters taken from the streets of New Orleans, and these tests indicated that all fish species and 10 of 12 invertebrate species were able to survive in this water. Because these species were able to survive in the full concentration of floodwaters, we can expect minimal ecological damage to the lake, according to DEQ Secretary Mike McDaniel. The discharge of floodwaters will be further diluted in ambient lake waters, resulting in concentrations of pollutants below levels of concern. Ongoing tests of lake water along the south shore have shown little or no degradation of water quality compared with hundreds of analyses conducted prior to floodwater pumping. Tests indicate lake water quality post-Katrina is similar to conditions found during normal stormwater runoff events. As predicted, hurricane insults to water quality occurred along the north shore. These included low dissolved oxygen and some fish kills in the tributaries, but these are brief events.

(Kevin Savoie and Brian LeBlanc, Louisiana Sea Grant College Program/LSU AgCenter) 10-6-05

Back to Top

Should I have my private well water sampled and who can test it for me?

The Louisiana Department of Health and Hospitals recommends testing of private well water samples for total coliform bacteria (fecal coliforms and E. coli) following flooding, and total coliforms and nitrate annually. Additional analyses may be advisable after a flood or chemical release, and depending on factors that could provide evidence of contamination.

Questions to ask to determine what analyses may be appropriate after a flood.

  1. What parish is the sample from?
  2. How old is your residence and when was the well constructed?
  3. From what source did the flooding occur (pond, river, salt or brackish water), and the name (if applicable)?
  4. How near a municipality is your well?
    a. What municipality?
    b. Was the municipality flooded?
    c. Were fuel stations with underground tanks flooded near you residence?
    d. Were chemical storage facilities or points of sale flooded near your residence, and what chemicals may have been stored there?
  5. What is the land use in the immediate location of the well?
    a. Farming, and what crops?
    b. Confined animal operations and what animals?
    c. Industrial activities and what kind of industry (petrochemical, plastics, pesticides, herbicides, other)?
  6. Have there been unexpected chemical emissions from nearby industries prior to flooding or during the flooding?
  7. Is there a noticeable color or odor change from the water after 2-3 minutes of purging?
  8. Have contaminants been detected in nearby wells?

Taking Your Own Samples

First, contact the W. A. Callegari Environmental Center, LSU AgCenter prior to sample collection to determine appropriate analyses and necessary sample size:
Phone: (225)765-5155
Fax: (225)765-5158
David Schellinger, Lab Manager ( or
Javed Iqbal, Quality Assurance Officer (

  • Obtain clean plastic or glass container(s) washed with a phosphate-free soap, rinsed with good quality filtered water and air dried (never remove the cap until taking sample).
  • Never touch the inside of lid or container.
  • Samples must be obtained from a faucet closest to the well.
  • Sterilize the faucet inside and out
    • Using a three-inch flame from a butane torch circling the inside and outside of the opening several times
    • Using chlorine bleach and a brush or rag
  • Fully open the faucet for 2-3 minutes (hand pumps 5-10 minutes).
  • Remove lid(s) from sample container(s) and fill ¾ full and replace lid(s) immediately.
  • Store and ship samples in ice.

Overnight delivery of samples to:

W. A. Callegari Environmental Center
1300 Dean Lee Drive
Baton Rouge, LA 70820

(Bill Carney, LSU AgCenter) 9-22-05

Back to Top

How do I clean and disinfect my well after a flood?

After a flood, it is important to take every precaution to ensure the safety of your well water. First, it is necessary to inspect and clean the well and pump before using them. You may want to have your water well driller or contractor check out the well before using it.

Do not turn on the pump until an electrician or well contractor has checked the wiring. There is a risk of electrical shock! After the proper inspections have taken place, run the pump and discard the water until the well water runs clear.

Most important, after a flood, you should disinfect the well. This can be accomplished by following the procedures outlined below; however, it is advisable to hire a well contractor to disinfect the well for you.

  • Pump the well for several hours to reduce the cloudiness and contaminant levels in the water.
  • Pour four gallons of a chlorine bleach solution into the well. Chlorine bleach solution consists of one gallon of bleach with three gallons of clean water. Open every faucet and pump the water until the water coming out of the faucet smells like chlorine, and then turn off each faucet. If you do not smell chlorine at the faucet, add a little more chlorine solution until the smell is detected.
  • Let the system sit for 24 hours.
  • Open the faucets and run the water until the chlorine smell disappears.
  • Have the water sampled and tested. The water IS NOT safe for drinking until lab results show no indication of total coliform bacteria. You can discuss the final lab results with the lab or local parish health unit. It is important to remember that disinfection will not remove chemicals which may have contaminated your well during a flood.

(Bill Carney, LSU AgCenter) 9-22-05

Back to Top

What is being done to assess the environmental impact of Hurricane Rita in areas of southwest Louisiana?

The Louisiana Department of Environmental Quality (DEQ) and U.S. Environmental Protection Agency (EPA) have been assessing these impacts for several days. Flyovers along the coast from Wax Lake in St. Mary Parish to the Sabine River revealed 33 oil spills, but their severity has not been indicated. This assessment will continue. Flyovers of industrial areas did not reveal any problems, and ground assessments continue. Teams are investigating publicly owned sewage treatment facilities to determine if damage was done and if environmental problems are occurring. It is probable some localized fish kills will or have occurred due to sedimentation and resulting low dissolved oxygen, saltwater influx and other “normal” effects after hurricanes. For more information about the monitoring efforts, visit the Web site below.

(Brian LeBlanc, Louisiana Sea Grant College Program/LSU AgCenter) 10-6-05)

Back to Top