Aquifer Vulnerability Assessment

COMMUNITY ENGAGEMENT OPPORTUNITY

SHOREACRES COMMUNITY HALL 2625 Shoreacres Road Monday, January 27th, 2020 6:00 pm to 8:00 pm

CRESCENT VALLEY COMMUNITY HALL 1385 Highway 6 Wednesday, January 29th, 2020 6:00 pm to 8:00 pm


The Regional District of Central Kootenay would like to invite community members in Playmor Junction, Voykin Subdivision, Shoreacres and portions of Crescent Valley and South Slocan to two community workshops:

  • Learn about groundwater vulnerability in the study area
  • Help define key issues and concerns
  • Help problem solve
  • How will this study inform land use activity in the area?
  • What tools are available to protect and enhance groundwater resources?

AQUIFER VULNERABILITY ASSESSMENT – SHOREACRES AQUIFER

The Regional District of Central Kootenay initiated an Aquifer Vulnerability Assessment in response to concerns regarding water quality and quantity in the community of Shoreacres during the initial review of the Official Community Plan for the area. This project was initiated in January 2019.

The purpose of the Aquifer Vulnerability Assessment was to develop aquifer vulnerability mapping to inform land use policy and decision making within the project area. The report is intended to be a ‘screening tool’ and is not intended to guide site specific land use decisions at this time.

Communities included in this assessment are:

  • Playmor Junction
  • Voykin Subdivision
  • Shoreacres
  • Portions of Crescent Valley
  • Portions of South Slocan

DRASTIC BASED VULNERABILITY STUDY - SHOREACRES AQUIFER [PDF - 9 MB]

To view the presentation made to the RDCK Rural Affairs Committee meeting on December 11, 2019, please use the following link: Presentation [PDF - 1 MB]

WHAT IS A DRASTIC-BASED VULNERABILITY MAPPING

Intrinsic Aquifer Vulnerability Mapping is used to describe the relative degree of natural protection of groundwater resources from contamination due to the physical characteristics of the land and subsurface. This type of mapping is conducted at a regional scale and is used as a screening tool that can be used to support the regulation of land use in sensitive areas. These overview studies are not intended to replace site specific investigation or to be used for lot scale assessment.

The name DRASTIC represents each of the seven input parameters:

  • Depth to Water Table
  • Recharge (net)
  • Aquifer Media
  • Soil Media
  • Topography
  • Impact of the Vadose Zone
  • Conductivity (Hydraulic) of the Aquifer

Attributes are mapped and rated according to their relative ability to protect the groundwater resource from contamination.

D As water depth decreases, vulnerability increases, as contaminants can reach the aquifer more rapidly with less potential for natural dispersal

R As recharge to the aquifer increases, vulnerability increases, as downward movement of a contaminant is promoted

A The larger the grain size (sand versus silt or clay) in an aquifer leads to higher vulnerability due to permeability

S Course textured soils or thin soils will have higher vulnerability than fine textured soils

T As slope increases, vulnerability decreases as contaminants are more likely to run off than infiltrate

I The vadose zone is the unsaturated area below the soil and above the water table or aquifer

C As the aquifer hydraulic conductivity increases, vulnerability increases, as water and contaminants can move quickly and spread

Image: Simon Fraser University

WHAT DOES IT ALL MEAN

HIGH VULNERABILTY

Material above the water table or aquifer provides the least natural protection from surface contamination.

These areas are typically unconfined sand and gravel aquifers which have low depth to water, a high water table or high permeability.

MODERATE VULNERABILTY

Material above the water table or aquifer provides limited natural protection from surface contamination.

These areas are typically unconfined sand and gravel aquifers which may have deeper water tables or some fine grained sediments, such as silts and clays, above them

LOW VULNERABILTY

Material  provides the highest degree of natural protection relative to other areas. This does not mean there is no vulnerability.

These  areas are usually well confined aquifers with un-fractured bedrock, low permeability or aquifers with deep water tables.

LIMITATIONS AND ASSUMPTIONS

  • Mapping is at a regional scale and is not meant to replace site specific investigations at the lot scale or for more detailed site planning
  • Only contamination from the surface is considered – mapping will not show vulnerability associated with underground improvements or developments such as: mines, underground storage tanks or other sub-surface features
  • Potential hazards or threats to groundwater quality should also be assessed to provide a more complete picture of RISK. This information is limited for this area due to incomplete records on septic disposal and storage of contaminants.

     

HOW WILL THIS INFORMATION BE USED

Aquifer Vulnerability Reports and Mapping can be used in a number of ways to inform community decision making. The report and associated mapping will inform the following:

  • Inform a collaborative process to decide community priorities for future development
  • Inform the development of best management practices for areas of high, moderate and low vulnerability

 

ADDITIONAL RESOURCES FOR THE PROTECTION OF GROUNDWATER

INTERIOR HEALTH AUTHORITY - CLEAN DRINKING WATER

ENVIRONMENTAL PROTECTION AND SUSTAINABILITY - GROUNDWATER WELLS AND AQUIFERS

 

 

The content on this page was last updated January 14 2020 at 10:24 AM