Linking climate change and geohazards

Geohazards? 1.What’s the short-list of geohazards potentially relevant to my MCCAP? 2.How are they relevant, and are they priorities? THANK YOU! Garth DeMont, Geoscientist with NS Department of Natural Resources Gavin Kennedy, Hydrogeologist with NS Department of Natural Resources John Drage, Hydrogeologist with NS Department of Natural Resources

Assessing Geological Hazards 4 of to develop a methodology to incorporate geology into the land use planning process coastal flooding & riverine flooding coastal erosion land sinking – sinkholes contamination of water from heavy metals in soil or acid rock drainage landslides / slope failure Geo-events that pose threats Picture from NS DNR Geological Services Division

Assessing Geological Hazards 4 of to develop a methodology to incorporate geology into the land use planning process Picture from NS DNR Geological Services Division Geohazard—Coastal erosion Picture from NS DNR Geological Services Division The need to establish setbacks should be informed by geology – both bedrock and surficial Coastal erosion risk will increase with sea level rise.

Assessing Geological Hazards 4 of to develop a methodology to incorporate geology into the land use planning process Picture from NS DNR Geological Services Division Geohazard—Karst Picture from NS DNR Geological Services Division Occurs in limestone & gypsum sinkholes water contamination Under the Nova Scotia Treatment Standard for Municipal Surface Source Water Treatment Facilities, once designated, karst areas are subject to water treatment standards.

Assessing Geological Hazards 4 of 30 Picture from NS DNR Geological Services Division Geohazard—Heavy Metals Toenails, Tap Water and You: The Arsenic Connection NS DNR Report of Activities: 2009

Assessing Geological Hazards 4 of 30 Geohazard—Heavy Metals Toenails, Tap Water and You: The Arsenic Connection NS DNR Report of Activities: 2009 In unstable climatic conditions where rocks and soils are saturated one week and dry the next there is a higher risk of transport into groundwater systems. Will that be our climate?

Assessing Geological Hazards 4 of 30 Geohazard—Acid rock drainage Pyrite and pyrrhotite oxidize when exposed to air, resulting in production of sulphuric acid and iron oxides. Sulphuric acid is soluble. Picture from NASA Earth Science Division

Assessing Geological Hazards 4 of 30 Geohazard—Acid rock drainage The amount of water that will fall in a ‘20 year return period’ rainfall (i.e., an event that has a 5% chance of happening any given year) will be: 5% more rain fall by the 2020s 9% more rain will fall by 2050s 16% more rain fall by the 2080s. Picture from NASA Earth Science Division

Assessing Geological Hazards 4 of 30 Picture from NS DNR Geological Services Division Geohazard—Slope stability Slope angle? What’s beneath our feet? On surface and underlying? How saturated is it? How warm is it?  different kind of assessment than coastal erosion  Slope Stability Guidelines for Development Applications

Decision Flow Diagram

Assessing Geological Hazards Understand how climate change can trigger certain hazards Are any of these hazards present in my jurisdiction? Where? Do they impose an intolerable risk? How urgent is the need to respond?

Anne Warburton