This paper outlines a new software tool, Water Modeler, which is a component of a Coastal Zone De... more This paper outlines a new software tool, Water Modeler, which is a component of a Coastal Zone Decision Support System. The Water Modeler can analyze a time series of water-level records (tide gauge observations) to determine the risk associated with a high water level from a storm surge event or long-term sea-level rise. The new tool has been applied in two case studies in Nova Scotia, Canada, where coastal flood-risk maps have been derived from high-resolution LiDAR digital elevation models. The first case study is for Annapolis Royal on the Bay of Fundy side of the province, while the second looks at the Kingsburg area of Lunenburg County on the Atlantic shore. The Saint John, New Brunswick, and Halifax tide gauge records were used for Annapolis Royal and Kingsburg, respectively, in the Water Modeler to examine the risks of coastal flooding. The Groundhog Day storm of 1976, which caused coastal flooding around the Bay of Fundy, was used as a benchmark for Annapolis Royal. At curr...
Much of the coast in the Canadian Maritimes is susceptible to erosion and flooding from storm-sur... more Much of the coast in the Canadian Maritimes is susceptible to erosion and flooding from storm-surge events and long-term sea-level rise. In recent years significant damage has occurred during storms in both urban and rural areas of the region. LiDAR technology has been employed to develop high-resolution digital elevation models (DEMs) as a basis for production of flood-risk maps. These
Canadian vessels equipped with multibeam bathymetry systems are in high demand by the Canadian Hy... more Canadian vessels equipped with multibeam bathymetry systems are in high demand by the Canadian Hydrographic Service (CHS) and by researchers from the Geological Survey of Canada (GSC). For several years, survey time for geological mapping was allocated in relatively small blocks of 10-20 days to provide as many applicants as possible the opportunity to collect multibeam bathymetry data. The resulting
ABSTRACT The contamination of shellfish harvesting areas by fecal bacteria in the Annapolis Basin... more ABSTRACT The contamination of shellfish harvesting areas by fecal bacteria in the Annapolis Basin of Nova Scotia, Canada, is a recurring problem which has consequences for industry, government, and local communities. This study contributes to the development of an integrated water quality forecasting system to improve the efficiency and effectiveness of industry management. The proposed integrated forecasting framework is composed of a database containing contamination sources, hydrodynamics of the Annapolis Basin, Escherichia coli (E. coli) loadings and watershed hydrology scenarios, coupled with environmental conditions of the region (e. g., temperature, precipitation, evaporation, and ultraviolet light). For integration into this framework, this study presents a viable methodology for assessing the contribution of fecal bacteria originating from a watershed. The proposed methodology investigated the application of high resolution remote sensing, coupled with the commercially available product, MIKE 11, to monitor watershed land use and its impact on water quality. Remote sensing proved to be an extremely useful tool in the identification of sources of fecal bacteria contamination, as well as the detection of land use change over time. Validation of the MIKE 11 model produced very good agreement (R-2 = 0.88, E = 0.85) between predicted and observed river flows, while model calibration of E. coli concentrations showed fair agreement (R-2 = 0.51 and E = 0.38) between predicted and observed values. A proper evaluation of the MIKE 11 model was constrained due to limited water sampling. However, the model was very effective in predicting times of high contamination for use in the integrated forecasting framework, especially during substantial precipitation events.
ABSTRACT Salt marshes exhibit striking vegetation zonation corresponding to spatially variable el... more ABSTRACT Salt marshes exhibit striking vegetation zonation corresponding to spatially variable elevation gradients which dictate their frequency of inundation by the tides. The salt marshes in the upper Bay of Fundy, a dynamic hypertidal system, are of considerable interest due to increasing recognition of salt marsh ecosystem values and the extent of prior conversion of salt marshes to agricultural lands, much of which are no longer in use. To determine the suitability of two potential restoration sites at Beausejour Marsh in New Brunswick, Canada, geomatics technologies and techniques were used to assess vegetation and elevation patterns in an adjacent reference salt marsh and the proposed restoration sites. Light detection and ranging digital elevation models (DEMs) were created for the reference marsh and the restoration sites in both the spring (leaf-off) and late summer (leaf-on, maximum biomass) periods. Aerial photographs and Quickbird multispectral imagery were used to visually interpret vegetation zones on the reference marsh and were field validated using vegetation characteristics from quadrats referenced with differential GPS. Elevation limits of the salt marsh vegetation zones were extracted from the DEM of the reference marsh and applied to the DEM of the restoration sites to determine the percentage area of each site that would be immediately suitable for new salt marsh growth. Of the two restoration sites assessed, one had experienced significant subsidence since dyking; only about 40 % of the site area was determined to be of sufficient elevation for immediate vegetation colonization. The second site, while more than 88 % suitable, would require the installation of a large dyke on the landward side of the restoration site to prevent flooding of adjacent lands. This study provides essential high resolution elevation and vegetation zonation data for use in restoration site assessments, and highlights the usefulness of applied geomatics in the salt marsh restoration planning process.
... Several basins developed in the Late Devonian - Early Carboniferous— including the Kennetcook... more ... Several basins developed in the Late Devonian - Early Carboniferous— including the Kennetcook, Shubenacadie (Giles and Boehner 1982) and St. Mary's Basins (Webster, 1996). ... 5). The structural deformation is localized within the basins - for example the Walton area (Fig. ...
Abstract. Coastal flooding from storm-surge events and sea-level rise is a major issue in Atlanti... more Abstract. Coastal flooding from storm-surge events and sea-level rise is a major issue in Atlantic Canada. Airborne light detection and ranging (lidar) has the spatial density and vertical precision required to map coastal areas at risk of flooding from water levels typically 12 m higher ...
This paper outlines a new software tool, Water Modeler, which is a component of a Coastal Zone De... more This paper outlines a new software tool, Water Modeler, which is a component of a Coastal Zone Decision Support System. The Water Modeler can analyze a time series of water-level records (tide gauge observations) to determine the risk associated with a high water level from a storm surge event or long-term sea-level rise. The new tool has been applied in two case studies in Nova Scotia, Canada, where coastal flood-risk maps have been derived from high-resolution LiDAR digital elevation models. The first case study is for Annapolis Royal on the Bay of Fundy side of the province, while the second looks at the Kingsburg area of Lunenburg County on the Atlantic shore. The Saint John, New Brunswick, and Halifax tide gauge records were used for Annapolis Royal and Kingsburg, respectively, in the Water Modeler to examine the risks of coastal flooding. The Groundhog Day storm of 1976, which caused coastal flooding around the Bay of Fundy, was used as a benchmark for Annapolis Royal. At curr...
Much of the coast in the Canadian Maritimes is susceptible to erosion and flooding from storm-sur... more Much of the coast in the Canadian Maritimes is susceptible to erosion and flooding from storm-surge events and long-term sea-level rise. In recent years significant damage has occurred during storms in both urban and rural areas of the region. LiDAR technology has been employed to develop high-resolution digital elevation models (DEMs) as a basis for production of flood-risk maps. These
Canadian vessels equipped with multibeam bathymetry systems are in high demand by the Canadian Hy... more Canadian vessels equipped with multibeam bathymetry systems are in high demand by the Canadian Hydrographic Service (CHS) and by researchers from the Geological Survey of Canada (GSC). For several years, survey time for geological mapping was allocated in relatively small blocks of 10-20 days to provide as many applicants as possible the opportunity to collect multibeam bathymetry data. The resulting
ABSTRACT The contamination of shellfish harvesting areas by fecal bacteria in the Annapolis Basin... more ABSTRACT The contamination of shellfish harvesting areas by fecal bacteria in the Annapolis Basin of Nova Scotia, Canada, is a recurring problem which has consequences for industry, government, and local communities. This study contributes to the development of an integrated water quality forecasting system to improve the efficiency and effectiveness of industry management. The proposed integrated forecasting framework is composed of a database containing contamination sources, hydrodynamics of the Annapolis Basin, Escherichia coli (E. coli) loadings and watershed hydrology scenarios, coupled with environmental conditions of the region (e. g., temperature, precipitation, evaporation, and ultraviolet light). For integration into this framework, this study presents a viable methodology for assessing the contribution of fecal bacteria originating from a watershed. The proposed methodology investigated the application of high resolution remote sensing, coupled with the commercially available product, MIKE 11, to monitor watershed land use and its impact on water quality. Remote sensing proved to be an extremely useful tool in the identification of sources of fecal bacteria contamination, as well as the detection of land use change over time. Validation of the MIKE 11 model produced very good agreement (R-2 = 0.88, E = 0.85) between predicted and observed river flows, while model calibration of E. coli concentrations showed fair agreement (R-2 = 0.51 and E = 0.38) between predicted and observed values. A proper evaluation of the MIKE 11 model was constrained due to limited water sampling. However, the model was very effective in predicting times of high contamination for use in the integrated forecasting framework, especially during substantial precipitation events.
ABSTRACT Salt marshes exhibit striking vegetation zonation corresponding to spatially variable el... more ABSTRACT Salt marshes exhibit striking vegetation zonation corresponding to spatially variable elevation gradients which dictate their frequency of inundation by the tides. The salt marshes in the upper Bay of Fundy, a dynamic hypertidal system, are of considerable interest due to increasing recognition of salt marsh ecosystem values and the extent of prior conversion of salt marshes to agricultural lands, much of which are no longer in use. To determine the suitability of two potential restoration sites at Beausejour Marsh in New Brunswick, Canada, geomatics technologies and techniques were used to assess vegetation and elevation patterns in an adjacent reference salt marsh and the proposed restoration sites. Light detection and ranging digital elevation models (DEMs) were created for the reference marsh and the restoration sites in both the spring (leaf-off) and late summer (leaf-on, maximum biomass) periods. Aerial photographs and Quickbird multispectral imagery were used to visually interpret vegetation zones on the reference marsh and were field validated using vegetation characteristics from quadrats referenced with differential GPS. Elevation limits of the salt marsh vegetation zones were extracted from the DEM of the reference marsh and applied to the DEM of the restoration sites to determine the percentage area of each site that would be immediately suitable for new salt marsh growth. Of the two restoration sites assessed, one had experienced significant subsidence since dyking; only about 40 % of the site area was determined to be of sufficient elevation for immediate vegetation colonization. The second site, while more than 88 % suitable, would require the installation of a large dyke on the landward side of the restoration site to prevent flooding of adjacent lands. This study provides essential high resolution elevation and vegetation zonation data for use in restoration site assessments, and highlights the usefulness of applied geomatics in the salt marsh restoration planning process.
... Several basins developed in the Late Devonian - Early Carboniferous— including the Kennetcook... more ... Several basins developed in the Late Devonian - Early Carboniferous— including the Kennetcook, Shubenacadie (Giles and Boehner 1982) and St. Mary's Basins (Webster, 1996). ... 5). The structural deformation is localized within the basins - for example the Walton area (Fig. ...
Abstract. Coastal flooding from storm-surge events and sea-level rise is a major issue in Atlanti... more Abstract. Coastal flooding from storm-surge events and sea-level rise is a major issue in Atlantic Canada. Airborne light detection and ranging (lidar) has the spatial density and vertical precision required to map coastal areas at risk of flooding from water levels typically 12 m higher ...
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Papers by Tim Webster