Treatment Wetland Types

Question 1

Municipal wastewater wetlands

Answer 1

• In Europe: Subsurface flow wetlands replaced secondary treatment
• In North America: Surface flow wetlands for polishing

• Best for removing:
– Organic matter
– Suspended solids
– Inorganic nutrients
– Trace metals
– Toxic chemical

Question 2

Mine Drainage Wetlands

Answer 2

• Drainage from coal mines
– Low pH
– High concentrations of Iron, Sulfate, Aluminium, trace metals

• Wetlands can
– Remove Iron
– Reduce Sulfates
– Improve pH

• Over 300 sites

Question 3

Urban Stormwater Treatment Wetlands

Answer 3

• Waste water is:
– Seasonal and sporadic
– Variable in quality depending on season or recent land use

• Conventional approach is dry detention pond or a wet detention pond

• Advantages to using wetlands:
– Water is treated
– Creates habitat for flora and fauna
– More aesthetic

Question 4

Agricultural Treatment Wetlands

Answer 4

1. Agricultural runoff wetlands
   - Treating non point pollution
   - Improve water quality before it enters
   streams and lakes
   - Case Study from Logan County, Ohio
2. Agricultural wastewater wetlands
   - Treats point pollution
   - Treats wastewater for confined dairy, cattle and swine, aquaculture operations

Question 5

River Diversion Wetlands

Answer 5

• River water is passed through adjacent floodplains or backwaters
• Analogs of oxbows or billabongs
• Simulations of agricultural runoff wetlands lower nutrient loads
• Effectively treats high sediment loads
• Case Study of the Mississippi Delta in Louisiana

Question 6

Landfill leachate wetlands

Answer 6

• Impermeable liners collect
groundwater

• Landfill leachate:
– ammonium - nitrogen
– chemical oxygen demand

• Options for treating leachate:
– Wetlands
– Spray irrigation
– Physical/chemical treatment
– Biological treatment
– Piping to a wastewater treatment plant