Lake Erie North Shore Watershed Plan - Niagara Peninsula ...

LAKE ERIE NORTH SHORE WATERSHED PLAN
Alternatives to traditional drainage design, such as wetland creation, floodplain development, and increasing
channel curvature should also be considered. Water quality should continue to be monitored within this
watershed. Monitoring the accumulation of sediment along the channel bed can be done by the use of sediment
traps throughout the watercourse. All recommendations should be discussed with the Drainage Superintendent.
4. Main Street East/White Road (BDCMb/BDCMc): This section of watercourse is managed as a municipal
drain; Beaver Dam Drain. It has been channelized and lacks any depositional features along the stream bed
which indicate little flow diversity within the channel. The riparian buffer along this field site is small but it does
contain a variety of vegetation types. Bank instability is present in the form of bare soil extending up the bank, as
well as undercut banks. No pools exist but there is stagnant water present throughout the field site. A foot bridge
that crosses the channel on private property may be narrower than the channel and therefore would be
considered a constriction. A bank protection structure, consisting of a concrete block wall, exists in the
downstream section of this field site protecting residential property. Numerous debris jams caused by fallen trees
are present in the upstream section. Measurements taken at channel cross sections would indicate that the
watercourse at this field site is moderately entrenched which results in flood waters having limited to no access to
the floodplain. Therefore, the energy within the flow is contained in the channel. Recommendations for this site
include not grading the channel banks too steep during the dredging process so that deep rooted vegetation can
become established along the banks and stabilize the soil. Alternatives to traditional drainage design, such as
wetland creation, floodplain development, and increasing channel curvature should also be considered. If the
foot bridge is found to be a channel constriction then it needs to be replaced with an appropriately sized bridge.
All recommendations should be discussed with the Drainage Superintendent.
These four field sites are within the designated municipal drain Beaver Dam Drain. Bank instability can be
identified at all four locations and some of the field sites had relatively deep unconsolidated sediment deposited
along the bed. Excessive sediment deposition can cause problems in the watercourse, such as lateral channel
adjustments, increased turbidity, filling in of pools, and impacting fish habitat. Long term monitoring of sediment
accumulation should be completed to avoid any potential problems and can be done by the use of sediment traps.
Water quality should continue to be monitored in this watershed. Foot bridges that are present along this
watercourse should be measured to ensure that they are not constricting the channel. This is due to the fact that it
can cause water to dam up behind it and therefore deposit sediment and/or scour the bed of the channel. The
majority of the field sites are entrenched to moderately entrenched, which means that flood waters will have little to
no access to the floodplain. Confining the flood waters to the channel results in the loss of the adjacent floodplain,
which impacts the hydraulic function of the watercourse (floodplains are storage areas for flood waters) and the
physical habitat (loss of floodplain vegetation and the organisms that live there). It will also change the channel
geometry overtime due to increased velocity, stream power, and channel slope. Increasing the variety and diversity
of native plant species will provide cover, habitat, and help to stabilize the soil along the banks. It will also help to
filter sediment and pollutants which may enter the watercourse from runoff. All recommendations should be
discussed with the Drainage Superintendent.
Naturalizing Drains and
Drain Best Management
Practices
In addition to having an impact on aquatic and riparian habitat, drain maintenance has the potential to become quite
costly through repeated maintenance activities. Naturalizing drains can potentially lengthen the time between
maintenance events by reducing the amount of sediment entering and remaining in the drain. Best Management
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