Biodiversity OffsettingInformation Session

OWES and Wetland Complexing

January 27, 2016

OWES• Ontario Wetland Evaluation System

• Provincial methodology for delineating and evaluating wetlands.

• Conducted either by the Ministry of Natural Resources and Forestry, or by certified evaluators.

• Final results must be approved by the MNRF.

OWES Wetland Delineation

• Delineation is primarily based on 50:50 wetland:upland plant species. The presence of these species are driven by soil hydrology.

• Wetland species to be used are outlined in the OWES methodology.

• Wetland units generally should be over 2 hectares in size to be evaluated.

OWES Complexing• Unit can be less than 2 hectares if it is within 750 metres of a

larger wetland to form a complex.

• Generally, the minimum size for a vegetation community to be included is 0.5 hectares.

• Commonly related in a functional way biologically, hydrologically or socially.

OWES Scoring

• Biological, Social, Hydrological, and Special Features components scored.

• Scores are based on the entire complex.

• Scores determine PSW or non-PSW (LSW).

Our Changing Landscape• Soils and geology indicate the Niagara peninsula was

approximately 50/50 upland/lowland prior to European settlement.

• Historical orthoimagery available since 1934.

• Shows changes in the landscape over time, and development of wetlands over the past 80 years.

Our Changing Landscape

• Wetlands in Niagara vary in age, vegetation and habitat composition, hydrologic complexity, etc.

• Vary from old growth to early successional.

Thank you!