Removal of Pathogenic Bacteria by Wetlands

1
Removal of Pathogenic Bacteria by Wetlands
Removal of Pathogenic Bacteria by Wetlands
Benjamin Tanner
2
Why Wetlands?

• Eco-friendly
• No addition of chemicals
• Natural attenuation
• Habitat for birds
• Look purdy

3
Pathogenic BacteriaWhat are They?

• Slow down.whats a bacteria?
• Ubiquitous coinhabitants of this planet
• Degraders
• Can grow EXPLOSIVELY
• Pathogens can cause disease
• Typically are similar in terms of morphology

4
Where Do They Come From?

• Toilets, mainly
• Zoonotic sources
• Insect vectors
• Occasionally, things like soil and water

5
Pathogenic Bacteria
Their Baggage
6
Pathogenic Bacteria
Their Baggage
7
Enteric Pathogens and Pathogenesis
PATHOGEN EFFECT
Toxigenic E. coli HUS/ (Bloody) Diarrhea
Shigella spp. HUS/ profuse GI illness and person to person transmission
Camplyobacter jejuni Symptoms of food poisoning
Toxigenic Cholera Often fatal GI illness
Salmonella spp. Nausea, cramps, diarrhea
Staphylococcus aureus Skin infection
8
Mechanisms of Inactivation/Removal

• Sedimentation (gravity)
• Competition/Biotic stresses
• Predation (protozoan grazers)
• Adsorption
• U.V. light

9
Does it Work?

• Approximate 2 log (99) reduction in bacterial
  pathogens
• Retention time is key
• Subsurface vs. surface wetland
• U.V
• Aesthetic appeal
• Insect vector control

10
Some Problems

• Migratory birds
• Salmonella, Campylobacter
• Dairy Wastewater Treatment
• Potentially concentrates a NASTY pathogen
  (O157H7) from cattle
• Groundwater Leaching