Planning and Regulations Terms

When the Cataraqui Region Conservation Authority reviews planning applications or permit applications under our Development, Interference with Wetlands and Alterations to Shorelines and Watercourses Regulation, we consider the impacts on the following:

  • wetlands
  • floodplains
  • steep slopes/erosion
  • waterbodies
  • fish habitat.

A more detailed explanation about why each of these is important is provided below.


Wetlands benefit our environment by storing water and releasing it slowly. They reduce flooding and recharge groundwater, lakes, rivers and streams when they release their stored water slowly over time. Wetland plants filter contaminants, prevent erosion and store nutrients. Wetlands also provide important habitat to a variety of wildlife including fish, birds and animals.

Building or filling in or near a wetland disrupts the natural functions of the wetland. Placing buildings in a wetland can result in wet basements and cracked foundations. It may also lead to charges being laid under Conservation Authority or other regulations.


The land next to a lake, river or stream that is anticipated to flood is called a floodplain. This area is usually defined through a study and mapping that accounts for weather, topography and soil types. The study determines how high the water will rise during a major storm and/or spring melt.

In this part of Ontario, we plan for the 1:100 year (1 in 100 year) flood. This means that a flood has a one per cent chance of happening in any year. We often refer to the 1:100 year flood as the regulatory flood because this is what is used in our regulations and planning policies.

The CRCA protects people and property from this flood by making sure that all buildings and structures are located outside of the floodplain and that the size of the floodplain is not reduced by filling. If fill is placed in the floodplain, the water that used to flow into that area during flood conditions moves into an area that did not previously flood. This could result in personal injury and property loss.

On Lake Ontario and the St. Lawrence River we also need to account for flooding that is caused by wave action. This additional factor is called wave uprush.

Steep Slopes/Erosion

Slopes along lakes and rivers can be unstable and dangerous as building sites.

Erosion is the process that occurs when the land surface is worn away. There are many different types of erosion, as well as many causes. The CRCA is primarily concerned with erosion along valleys, slopes next to lakes, rivers, streams and other waterbodies. In these areas, scouring from both constant water flow and from increased velocity due to runoff or storm events contributes to erosion. When trees and plants along slopes are removed, erosion worsens.

If a structure is built at the top of a slope without consideration for slope stability, it is possible that the slope could erode over time and the structure would be damaged or lost. Through the regulation permit process, the CRCA makes sure that all structures are located outside of areas subject to erosion.


This is an all-inclusive term that refers to all bodies of water including lakes, rivers, streams, creeks and ponds. A waterbody is sensitive to changes to its channel or along its shoreline. Altering a waterbody may harm water quality, limit fish passage, destroy habitat or increase siltation and the risk of flooding. You cannot straighten, change, divert or interfere with a waterbody without a permit from the CRCA.

Fish Habitat

Fish habitat is the spawning grounds and nursery, rearing, food supply and migration areas that fish depend on, directly or indirectly, to carry out their life processes. Fish include shellfish, such as clams and mussels, and crustaceans, such as crayfish, as well as marine animals at all stages of their life cycles.

Some important elements for fish habitat include:

  • in-water vegetation
  • shoreline vegetation
  • debris, such as dead stumps and logs
  • rock
  • clean water.