One third of areas along Hamilton's shoreline in 'poor' condition: report
A new study reveals Hamilton's most damaged areas along its shoreline and possible repairs
A study commissioned by the city of Hamilton says one third of 33 shoreline sites evaluated are in 'poor' condition and in need of major repairs after several years of high water and being battered by storms.
The city has prioritized the most damaged areas and is evaluating ways to protect the area that have deteriorated. While the report doesn't outline associated costs, it offers recommendations on how barriers might be repaired or replaced to hold up against extreme weather.
The report comes after years of massive storms damaging Hamilton's shoreline. Portions of trails have been washed away by rough weather, while residents along the shoreline continue to experience extreme flooding of their basements.
Recent years have also seen record-setting water levels, sending waves over barriers in place for protection. In April, the federal government pledged $12.7 million to help rebuild the shoreline, while city staff estimated that cleanup and protection would cost around $30 million.
The city, taking into account this study and usage, ranked the deteriorated areas from high to low priority for rehabilitation. Its top five highest priority sites are:
- Confederation Beach Park.
- Hamilton Beach.
- 1135 and 1137 North Service Road and Lewis Rd. right of way.
- Macassa Bay Marina.
- Windermere Road.
All the sites above were rated as poor, with the exception of Hamilton Beach. That site received a "good" rating because of its minor deterioration.
The study covered from the Lake Ontario shoreline from the lift bridge to the city-owned lands east of Confederation park, and in the harbour, the shoreline from Bayfront Park to Coote's Paradise. Consultants looked at areas like trail systems, open spaces, road right-of-ways, storm water outfalls, and beaches.
In total, there were 11 areas along the shoreline with poor sections, four areas with fair sections, and 11 areas with good sections. Three areas were labelled as having "various" levels of deterioration.
Lake Vista Park was the only "very good" rating, which means that there was little to no wear and doesn't pose a concern withstanding a "100-year storm event."
The report did not look at the Hamilton Harbour Waterfront Trail, as the trail had its own review in 2017, and will be brought forward to the committee in early 2020. Some of the 33 areas were also not officially evaluated for various reasons, like the Fifty Road Parkette, which is being redeveloped.
Right now, shoreline protection generally includes a concrete or rock wall, with "rock armour protection" toward the wall's bottom. But forceful waves off high water levels can crash into a wall and overpass it, allowing the erosion to happen on the inside.
The report also outlined temporary solutions the city can take to re-enforce these protections. For each site, the consultants recommended repairs to either the armoured slope or the 'crest' — the top — of the barrier or various other replacements.
It also suggested that raising or rearranging pathways in the larger areas would be the most permanent solution for areas with lower crest levels and a potential for flooding. More permanent solutions, according to the consultants, should be carried out by coastal engineers.
The city will address its high priority items in the next three years, secondary items in a "post three year window," and low items will be improved or modified in the next five to eight years. They'll review the order of prioritization yearly.
'Wave modelling' shows how lands will hold up
Consultants reviewed the sites over three days and then gathered details like topographic information, photos, and drone footage. From this research, officials could run "wave modelling," which showed how different waves — which were generated by a combination of water level, wind speed, and direction — would impact the shoreline.
The study also looked at how susceptible the sites were to "wave overtopping" — when a wave crashes over the protective barrier. If the land behind it isn't adequately protected, it can become scoured and erode.
"In general," the report says, "the sites are all exposed to low to moderate volumes of overtopping during extreme events."
Council approved undertaking the study at its May 2018 meeting. In its report, the city says that the study would cost around $340,000 was planned to have been funded from the capital reserve.
The city says it will get assistance from Infrastructure Canada's disaster mitigation and adaptation funding cost sharing program to fund the recommended changes to the infrastructure.
It was noted in the report that the conditions reported on were from May 2019, and further damage could have occurred over the following months and going forward.
It's expected that the work will be completed in eight years.