The Parks Creek Backflood Control Structure, part of NBMCA's natural hazard and flood management program, is located in Eva Wardlaw Conservation Area at the mouth of the Parks Creek on Lake Nipissing near Lakeshore Drive and Marshall Avenue in North Bay.
It was installed in 1994/95 to prevent high water levels in Lake Nipissing from backing up Parks Creek and flooding its surrounding low lands causing basement flooding and overcharging the municipal storm sewer system for approximately 350 homes. High Parks Creek flows can also create downstream overbank conditions, even at low lake levels, due to the flat streambed gradient and very low flow velocities. The control structure was implemented as a result of the recommendation in the 1992 Totten Sims Hubicki (TSH) “Environmental Study Report – Parks Creek Watershed Flood Damage Reduction Study”.
Tested and maintained annually, the structure was put into full operation on May 2, 2019 to deal with the rising waters of Lake Nipissing. Previously, it operated in response to high levels in Lake Nipissing in May 2009.
When the Parks Creek Backflood Control Structure is in operation, Eva Wardlaw Conservation Area is closed and water access is closed off. See Notice in Service Disruptions.
The layout of the structure entails three bays spanning the creek bed with manually operated installable/removable galvanized steel stop logs. Construction includes two concrete bank abutments one on either side of the creek, two intermediate concrete piers founded on the creek bed, a galvanized metal grate deck with handrails and two approaches with gates for restricted access.
There is a pump chamber with two large electric pumps (with 0.3 cubic metre per second flow capacities each) to transfer the water from the creek upstream of the dam to the downstream side of the flood control structure when the stop logs are in place. Water enters the pump chamber via a manually operated sluice gate on the upstream side of the dam.
When required, stop logs are installed in the three bays of the structure to prevent backflooding. The pump station on the upstream side of the dam is activated to transfer the creek’s normal water flows to the downstream side. During major watershed runoff events, NBMCA installs an additional large portable pump to increase transfer flows to the downstream side of the structure.
A boom is also installed upstream of the dam to stop debris and restrict any boats or paddlers from reaching the dam by the creek. Eva Wardlaw Conservation Area is closed while the dam is in operation.
The structure has an “alert” system, a light which changes from green, to amber, to red depending on the conditions for both Lake Nipissing levels and Parks Creek Flows. They represent low, moderate and high operational alert and preparedness status for stop log and/or pumping operation. During a Red Alert condition, the pumps are switched to standby by the operator via the control panel located in the electrical building. The pumps start and stop automatically activated by floats located in the first chamber.
GREEN SIGNAL – Lake Nipissing level is at Operational Target Range of 195.75 m to 195.95 m elevation – May to Oct
AMBER SIGNAL – Lake Nipissing is approaching 196.1 m elevation (just below Parks Creek Flood Damage Threshold Elevation) – May to Oct
RED SIGNAL – Lake Nipissing is at and above Parks Creek Flood Damage Threshold Elevation of 196.2 m elevation.