The Fishway

The spring flooding of 2017 were devestating. Help us to restore the Fishway and Cootes Paradise

The Fishway is located at the outlet of Cootes Paradise Marsh, a short walk from the Princess Point accessed along the Desjardins Trail. As part of the marsh restoration, it is a barrier designed to keep the large non-native carp in Hamilton Harbour and out of the marsh, while maintaining the natural flow of water and native fish. After a century of decline, the marsh has improved each year since the Fishway’s installation. In 1996, about 70,000 common carp dominated the marsh; the barrier has excluded 95+% since its installation. You can experience a rejuvenating Cootes Paradise Marsh through one of the many public or school programs, or visit the Fishway during the spring migration of spawning fish from Lake Ontario.

Highlights of 20 years of restoration progress as measured between 1996 and 2016 include:

  • Water clarity improved from 30 cm to 50 cm, with periods of  very clear water occurring in recent years
  • Submergent aquatic plants increased from 0 hectares to 80 hectares.
  • Wetland plants overall increased by 105 hectares and now include 28 species (up from 8 species)
  • Emergent marsh vegetation increased from 15 to 39 hectares, mostly in the form of cattails – with 14 species present
  • Wild Rice, once totally lost, now grows in 30 locations
  • Native Fish increased by six fold (graph below).
  • Amphibians increased from 3 to 5 species and numbers have increased 8 fold
  • Planted over 200,000 wetlands plants (including 150,000 cattails covering 3 hectares), assisting with the re-establishment of many lost species.

Understanding the results

Ongoing fish deaths in adjacent Hamilton Harbour due to impaired oxygen levels and fish diseases such as VHS (which arrived 2007) continue to suppress fish numbers, despite improved marsh reproductive habitat. The impaired oxygen is a direct result of large volumes of partially and untreated sewage entering the harbour. The decomposing sewage uses up the oxygen, particularly through the processes of ammonia de-nitrification. Upgrades to wastewater treatment systems in Hamilton and Burlington are underway to correct this issue through the HHRAP.

Educational opportunities

The Fishway provides excellent opportunities for the public to view native fish up close, and learn about the conservation projects that are helping to restore this ecologically sensitive wetland. Public tours are available during regular operating hours, and school tours can be booked through our educational programs.