Economic Evaluation of the Potential Impacts of the Erosion of Quebec's
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Economic evaluation of the potential impacts of the erosion of Quebec’s maritime coasts in a context of climate change Research report submitted to Ouranos Under the direction of Pascal Bernatchez, Ph.D. May 2015 PRODUCTION TEAM Management and research Pascal Bernatchez, Ph. D. Coastal geomorphology and remote sensing Project manager Professor and Chairholder, Research Chair in Coastal Geoscience Laboratoire de dynamique et de gestion intégrée des zones côtières (LDGIZC) (coastal zone dynamics and integrated management laboratory) Biology, chemistry and geography department Université du Québec à Rimouski (UQAR) Email: [email protected] Research team Steeve Dugas, B.Sc., Research Professional, LDGIZC, UQAR Data processing and analysis, geomatics, writing Christian Fraser, M.Sc., Research Professional, LDGIZC, UQAR Data analysis, writing Laurent Da Silva, M. Sc., Economist, Ouranos Economic research, processing and analysis and writing Maude Corriveau, M.Sc., Research Professional, LDGIZC, UQAR Data processing and validation Nicolas Marion, B.Sc. student, UQAR Data processing (transfer of assessment roll parcels) Mia Charette, B.Sc. student, UQAR Data processing (Transfer of assessment roll parcels) Tessa Parisé, B.Sc. student, UQAR Data processing (Transfer of assessment roll parcels) Caroline Côté, Master’s degree (DESS) student, UQAR Data processing (Transfer of parcels identifying railways) Collaborators François Morneau, M. Sc., Scientific Coordinator, Ouranos Manon Circé, M. A., Senior Economist, Ouranos Xavier Mercier, M. Sc., Economist, Ouranos Claude Desjarlais, M. Sc., Senior Economist, Consultant, Ouranos Ursule Boyer-Villemaire, M. Sc., Oceanographer, Consultant, Ouranos Susan Drejza, M. Sc., Research Professional, LDGIZC, UQAR Complete reference Bernatchez, P., Dugas, S., Fraser, C. and Da Silva, L. (2015). Economic evaluation of the potential impacts of the erosion of Quebec’s maritime coast in a context of climate change. Coastal Zone Dynamics and Integrated Management Laboratory, Université du Québec à Rimouski. Report submitted to Ouranos, 45 p. and appendixes. ii ACKNOWLEDGEMENTS This study was undertaken with the financial support of Natural Resources Canada, the Green Fund under the 2013-2020 Climate Change Action Plan and Ouranos. We would like to thank the ministère des Affaires municipales et de l’Occupation du territoire du Québec (MAMOT) (Quebec Municipal Affairs and Land Occupancy Ministry), the RCMs (Regional County Municipalities) and the municipalities for their property assessment rolls and cadastral data. iii SUMMARY This study is the first economic assessment of the potential impact of coastal erosion on Quebec maritime infrastructures in the context of climate change, if no new adaptation measures are implemented and those already in place are not maintained. All buildings, roads and railways were identified using high-resolution mapping and they were assigned a value of exposure to erosion between now and 2065. The calculation of exposure is based on two parameters: 1) the probable rate of shoreline or coastline migration anticipated for each homogeneous geomorphological unit and 2) a safety margin that varies depending on coast characteristics. This economic evaluation was performed in constant 2012 dollars, based on assessment rolls and costs from past projects. Thus, the value of exposed buildings was estimated from the adjusted property value for the same reference year, 2012. The property value considers the marketplace, but slightly underestimates the real value. For roads and railways, the replacement value of these infrastructures, as well as protection works, was given priority. These estimates provide a scope of potential losses and not an accurate assessment of the amounts that must be invested over the next 50 years to maintain and replace infrastructure at risk. The area under study covers 3220 km of coastline and includes 16 regional county municipalities (RCM) spread out between the Bas-Saint-Laurent, the Côte-Nord, the Gaspésie and the Îles-de- la-Madeleine. The results of the study indicate that 5426 buildings throughout the territory will be exposed by 2065 if no adaptation measures are implemented and existing works are not maintained, keeping a safety margin of at least 5 metres from the coastline. The value of these buildings, in 2012 dollars, is $732 million. There are also 294 km of roads and 26 km of railways that will be exposed by 2065, representing a value of $776 million. The potential economic loss for the period between 2015 -2064, i.e. the next 50 years, is estimated at $1.5 billion. In terms of buildings exposed to erosion, residential buildings will be those mainly affected, representing 83% of the value of all buildings exposed by 2065. In the Bas-Saint-Laurent administrative region, the number (41%) and value (53%) of buildings potentially exposed by 2065 are the highest in maritime Quebec. In terms of the number of buildings, the most markedly affected RCM is Manicouagan on the Côte-Nord, while the RCM of Rimouski-Neigette has the highest total value. An overview of transport infrastructure threatened by erosion indicates that exposed municipal and local roads dominate with 154 km, closely followed by national roads with 138 km. However, the estimated cost to maintain or replace exposed national roads is much higher, i.e. 60% of the total value of transport infrastructure exposed to coastal erosion by 2065. In the Gaspésie – Îles-de-la-Madeleine administrative region, the length (54% of the coastline) and value (79% of the total) of potentially exposed transport infrastructure by 2065 are by far the highest in maritime Quebec, specifically in the RCM of La Haute-Gaspésie. Lastly, the results of this study highlight the importance of preventive management of coastal risks that would significantly limit the costs associated with coastal erosion. iv TABLE OF CONTENTS Production team ________________________________________________________ ii Acknowledgements _____________________________________________________ iii Summary ______________________________________________________________ iv Table of contents _______________________________________________________ v List of figures __________________________________________________________ vi List of tables ___________________________________________________________vii List of appendices _______________________________________________________vii 1 Introduction __________________________________________________________ 1 1.1 Coastal erosion __________________________________________________________ 1 1.2 Mandate and objectives ___________________________________________________ 1 1.3 Study area ______________________________________________________________ 2 2. Methodology ________________________________________________________ 3 2.1 Future coastal change scenarios _____________________________________________ 3 2.1.1 Recent climatic and oceanographic conditions ______________________________________ 3 2.1.2 Coastal change patterns and delineation of homogeneous geomorphological units _________ 4 2.1.3 Choosing probable migration rate ________________________________________________ 5 2.1.4 Coastal protection works ________________________________________________________ 6 2.1.5 Coasts that accumulate sediments ________________________________________________ 9 2.2 Mapping of exposed elements ______________________________________________ 9 2.2.1 Point data processing: buildings and land __________________________________________ 9 2.2.2 Linear data processing: roads and railways ________________________________________ 10 2.3 Calculation of exposure ___________________________________________________ 11 2.4 Safety margin ___________________________________________________________ 12 2.4.1 Margin proposed for buildings __________________________________________________ 12 2.4.2 Margin proposed for roads and railways __________________________________________ 12 2.5 Economic evaluation of exposed elements ___________________________________ 13 2.5.1 Economic evaluation principles __________________________________________________ 13 2.5.2 Property assessment of buildings ________________________________________________ 13 2.5.3 Value of replacing or moving roads and railways ____________________________________ 14 2.5.4 Property assessment of developed and undeveloped land ____________________________ 18 3. Overview of the exposure of buildings, roads and railways in maritime Quebec __ 19 3.1 General overview ________________________________________________________ 19 v 3.2 Buildings _______________________________________________________________ 21 3.3 Roads and railways ______________________________________________________ 30 3.4 Discussion on the exposure of roads ________________________________________ 36 5. Conclusion __________________________________________________________ 38 References ___________________________________________________________ 39 LIST OF FIGURES Figure 1. Location of the study area ________________________________________________________ 2 Figure 2. Equation used to calculate the exposure of buildings, land and transport infrastructure to coastal erosion (modified from Fraser et al., 2014a, b, c; Drejza et al., 2014a, b) __________________________ 11 Figure 3. Spatial distribution of costs related to the exposure of buildings, land areas and transport infrastructure in maritime Quebec by 2065 _________________________________________________ 20 Figure 4. Number of buildings