The schedule that Ted Tam used during the April 4, 2005 meeting is part of the HHSP Environmental screening report dated October 2001, prepared by Jacques Whitford Environmental Limited (Appendix C sewage treatment concept plan alternatives). There are a total of four drawings in Appendix C. Each of the drawings shows different treatment plant alternatives. The blue areas represent potential diffuser siting area.
The blue areas represent the acceptable potential outfall siting area. It originates from a summary report submitted to Halifax Regional Municipality by the Halifax Harbour Solutions Project Team: This team consisted of Jacques Whitford Environmental Limited, R.V. Anderson Associates, KPMG, O'Halloran Campbell Consultants, Coastal Oceans, R.H. Loucks Oceanology and Dale Knox Engineering.
The above-mentioned reports can be viewed at the HHSP website:
Harbour Solutions Advisory Committee - Final Report to Council (PDF 747KB)
Summary Report to HRM on Halifax Harbour Solutions Project (PDF 4.29MB)
Section 3 of the summary report to Halifax Regional Municipality by the Halifax Harbour Solutions Project Team addresses the overall concept plan for sewage treatment and what was used to propose potential areas for the treatment facilities, outfalls and the number and size of plants.
The original CEAA approval was for 20:1 diffusers and the current proposed design is for 50:1 and the physical location is still within the diffuser zone previously identified in the summary report to Halifax Regional Municipality by the Halifax Harbour Solutions Project Team.
The blue areas are the acceptable diffuser zones under the CEAA screening process.
Staff will obtain information on this study from the designer.
The effluent quality is: Suspended solid 40 mg/L, BOD 50 mg/L and fecal bacteria less than 500/100ml.
No. The current sampling program did not have sampling points from Dartmouth Cove. There are three stations on a transect between the Dartmouth (Peace Pavilion) and Halifax waterfronts (many other sites are sampled throughout the Harbour also).
HHSP will arrange to take five monthly surface water quality samples in Dartmouth Cove during the next six months (May - October 2005) to provide baseline information on the water quality.
Starting from Ferguson Road, a gravity sewer along the CN right-of-way to Jamieson Drive. This gravity sewer accepts the flows from Wallace and Grove Street.
A new pumping station will be constructed at Jamieson Street. This station will pump the flow collected from Ferguson, Wallace and Grove to Lyle Street. The forcemain goes through Canadian Forces Base Dartmouth property and ends at Lyle Street.
The flow from Lyle Street flows to Park Avenue by a gravity sewer.
The existing pumping station at Park Avenue will be modified and sewage will be pumped to Alderney Drive via Church Street.
The forcemain from Park Avenue continues along Alderney Drive to an existing outfall manhole. This existing outfall manhole will be converted to an air release chamber and the forcemain will connect to an existing pipe that goes to the Dartmouth Cove pumping station. The alignment will go through the Irving Dartmouth Marine Slips property. The forcemain continues along the CN rail corridor.
The King Street pumping station will be modified. The Dartmouth Cove pumping station and screening plant will be modified to pump into the forcemain. This forcemain terminates at the wastewater treatment plant. (All the existing pumping stations in the Dartmouth Cove area will still be required. The only difference is the direction of flow of the existing forcemain. Instead of pumping the sewage to an outfall in the Cove, the sewage is pumped to the new wastewater treatment plant).
From the South end of Dartmouth, a new pumping station will be built at Melva Street. The forcemain will follow the CN right-of-way to Cuisack Street where it will flow by gravity to the treatment plant.
The edge of the diffuser zone is approximately .25 km from shore. The diffusers are inside the diffuser zone and are approximately .35 km from shore.
There is an extremely low probability that there would be material washing up on Sandy Cove. The effluent leaving the treatment plant will have been treated. Flows up to four times the average dry weather flow will be diverted to the wastewater treatment plant for treatment and flows in excess of four times the average dry weather flow will be screened and discharged to the Harbour. This typically happens in extreme wet weather conditions. Therefore, at peak weather conditions, the excess flow will be discharged to the Harbour after it goes through a screen. The openings in the screen are no larger than 12 mm. Solids greater than 12 mm and floatables shall be removed from the overflowed wastewater and diverted automatically to the collection system to be routed to the treatment plant.
