RESILIENT COASTS FOR SALMON SPOTLIGHT COMMUNITIES
Regional District of Nanaimo
For the purposes of the Resilient Coasts for Salmon initiative, the Regional District of Nanaimo study area covers 187.2 km of marine shoreline along the Strait of Georgia, with data derived from imagery collected up to 2022.
The area of focus for this report is the Traditional Territory of the Hul’q’umin’um’ speaking peoples – the Snuneymuxw and Snaw-naw-as First Nations, colonially known as the Regional District of Nanaimo, on southeastern Vancouver Island.
Key Findings
Shoreline Modifications
Man-made structures like seawalls and riprap, often built to protect shoreline infrastructure, can actually exacerbate erosion by redirecting wave energy to nearby areas. These modifications also remove key intertidal habitats and food sources essential for the growth and survival of juvenile salmon and forage fish. By stripping away the natural complexity of coastal ecosystems, shoreline modifications reduce their capacity to support biodiversity and adapt to rising sea levels.
Extent of shoreline modification
As of 2022 (when the boat-based imagery was collected), approximately (INSERT total length of modified shoreline) m of (INSERT community)’s shoreline has been modified, while (INSERT total length of natural shoreline) m remains natural. This indicates that roughly (INSERT percentage) % of the community’s shoreline is classified as modified – Figure 1.
Figure 1. Coastal modifications (shown in blue) with the extent of data collection outlined by red dashes.
Most common shoreline modification types
The most common modification types were (INSERT most common mod type) (percentage), (INSERT second most common mod type) (percentage), and (INSERT third most common mod type) (percentage) – see Figure 2.
Figure 2. The percentage of modified shoreline by modification type.
Most common materials used in shoreline modifications
The type of material most utilized for shoreline modification was concrete (INSERT most common mod material) (percentage), (INSERT second most common mod material) (percentage), and (INSERT third most common mod material) (percentage) – see Table 1. If the unknown/undefined category is mentioned above INSERT: The unknown/undefined category indicates that the recorder was not able to determine the material that was used, due to issues with image clarity or obstruction, or in cases when a mix of materials were used.
Table 1. The percentage of modifications, based on the type of material used in the modifications.
| Material | Percentage of Modifications |
| INSERT | INSERT |
| INSERT | INSERT |
| INSERT | INSERT |
| INSERT | INSERT |
| INSERT | INSERT |
Overwater Structures
Overwater structures, like docks and piers, cast heavy shade that degrades nearshore habitat. Juvenile salmon avoid these shaded areas, which alters their natural foraging and migration patterns by forcing them into deeper waters. There, they expend more energy and face greater predation risk. The reduced light also limits the growth of essential habitats like eelgrass and algae, along with the diverse communities they support.
Number of overwater structures total and by type
The total number of overwater structures in (INSERT community name) is (INSERT total number of overwater structures), consisting primarily of (INSERT first most common type) (number), (INSERT second most common type) (number), (INSERT third most common type) (number), (INSERT fourth most common type) (number), and (INSERT fifth most common type) (number) – see Figure 3.
Figure 3. The extent of overwater structures within (INSERT community).
Log Accumulation
While logs are a natural part of coastal ecosystems, the escape of modified logs from log booms is leading to excessive accumulation. These logs can scour beaches, altering sediment composition and smothering nearshore vegetation. Unlike natural logs, modified logs are stripped of root balls and branches, making them unstable and prone to rolling across critical habitats that juvenile salmon and forage fish rely on for growth, food, and shelter.
Extent of log accumulation
Of the total shoreline, (INSERT)% (INSERT m) was found to have an extreme (>89%) accumulation of logs, with another (INSERT)% (INSERT m) with high accumulations (50 to 89% coverage), and (INSERT)% (INSERT m) having moderate levels (20% to 49%) of the beach covered by logs – see Table 2. It should be noted that the moderate log accumulation category also represents a significant coverage of logs – whereby 20-49% log coverage on a given beach could negatively impact shoreline habitat.
Table 2. The length of shoreline (in percentage and metres) by category of log accumulation.
| Log Accumulation | Percentage of Shoreline | Metres |
| Extreme (>89%) | INSERT | INSERT |
| High (50 to 89%) | INSERT | INSERT |
| Moderate (20 to 49%) | INSERT | INSERT |
| Low/None (<20%) | INSERT | INSERT |
To access and download the Resilient Coasts for Salmon layers for the Regional District of Nanaimo, click here. <– CHANGE LINK
