A marine construction company has been fined for discharging materials into the St. Lawrence River.

Kingston-based Inner Harbour Marine Services Limited was convicted of one violation under the Ontario Water Resources Act, fined $45,000 plus a victim fine surcharge of $11,250, and given nine months to pay.

The company conducts in-water construction projects for residential and commercial clients including shoreline remediation, dock construction and break wall construction.

In the fall of 2022, Inner Harbour was contracted to conduct shoreline restoration and stabilization work at a private residence in Kingston. The site is located on a small peninsula in the St. Lawrence River known as Treasure Island. The waters adjacent to the site are within a provincially significant wetland and are a habitat for many species of fish, amphibians, turtles and invertebrates.

Prior to commencing work, Inner Harbour obtained permits from the Cataraqui Region Conservation Authority and the Ministry of Natural Resources with respect to the proposed shoreline work. The permits required that erosion and sedimentation control measures be installed before beginning the work. The permits also required that machinery be operated in a manner that prevented sediment from entering the water.

In April 2023, a hydrogeologist with the ministry observed that Inner Harbour had been excavating the shoreline and installing large pieces of armour stone at the site without the use of sedimentation control measures.

Additionally, excavator tracks were visible in the water and there was a visible plume of sediment and silt discharging from the site into the St. Lawrence River.

As a result, an environmental compliance officer and a surface water scientist conducted a site inspection and observed Inner Harbour conducting excavation work on the shoreline while sediment and silt continued to discharge into the St. Lawrence River. A roll of silt fencing was present on site but had not been installed.

The surface water scientist collected water samples from the St. Lawrence River at the sediment plume and surrounding waters. Inner Harbour was instructed to stop the work until sediment control measures were properly installed, to which they complied.

It was subsequently determined that Inner Harbour’s shoreline construction work resulted in a discharge of sediment and silt into the St. Lawrence River that lasted for a minimum of 20 hours.

Further, the concentration of total suspended solids within the sediment plume were two orders of magnitude above background levels in the St. Lawrence River.

The duration and concentration of the sediment discharge impaired the quality of the water and likely had moderate and sublethal negative impacts on several local fish species and aquatic invertebrates.

The ministry’s Environmental Investigations and Enforcement Branch investigated and laid charges which resulted in the conviction.