Oldman Watershed Priority Mapping Project

Project Overview

With our growing population, the quality and availability of water in southern Alberta has never been more important. Yet many of our activities have a negative impact on how water interacts with the landscape. This project identifies those areas that if kept intact should provide the greatest benefit as it relates to water quality, flood mitigation, and drought resiliency. The premise being that disturbing some areas will have a greater impact on water quality, storage, and runoff than other areas (based on factors such as slope, proximity to watercourses, vegetation, precipitation, soil). The purpose of the maps is to help organizations to focus their efforts on areas important for water. They can also be used by governments to assess the appropriateness of different land uses as they relate to water.

SALTS would like to thank the Alberta Government’s Watershed Resiliency and Restoration Program (WRRP) for supporting this project financially. We believe that this project is an excellent example of filling a gap in the available applied science that will help to facilitate and focus concrete actions towards the better management of Alberta’s watersheds.

Technical Report

This report summarizes the process used to come up with the maps including the experts consulted, datasets chosen, and mapping methodology employed.

Overlay Results Map

This map shows those areas that if kept intact will provide the greatest value in terms of maintaining water quality, storing water, and slowing runoff. The areas in red, orange, and yellow have the highest values in this respect.

Priority Sub-basins Map

This map takes the data from the overlay results and identifies which sub-basins within the watershed hold the greatest coverage of high priority areas (in this case areas red though yellow). This allows organizations or communities to focus on sub-basins of high priority.

Priority Map Book (large 39 MB)

The map book contains the same information as the overlay results but at a much higher resolution and with more detailed features to help orient users. The map book allows a user to zoom in and look at the landscape at the level of an individual quarter section.

Georeferenced Image for GIS (large 20 MB)

This high resolution georeferenced TIF along with TFW and LYR files should allow Arc GIS users to import the image of the overlay results and use it alongside other datasets as a tool to support organizational, project, or land-use planning.

Key notes:

Given their scale and emphasis, the maps do not always highlight the significant value of riparian areas immediately adjacent to waterbodies and watercourses (e.g. 0-50 metres). These areas have their own value from a habitat and watershed services standpoint that should be taken into consideration on top of the data presented in this project. While not all rivers, creeks, lakes, and wetlands are shown as red, this does not mean that riparian areas immediately adjacent to the water are not of high value.

If users download the maps and open them in Adobe Acrobat (not reader) different map features can be turned on and off by toggling the layers icon on the left-hand side of the screen. This allows some customization of maps by different users for different viewing/presentation purposes.