Public Information Centre (PIC) November r 29, , 2018 PURPOSE - - PowerPoint PPT Presentation

Sewage Works Improvements Town of Huntsville Mountview Wastewater Treatment Plant to Golden Pheasant Wastewater Treatment Plant Conveyance Strategy

Public Information Centre (PIC)

November r 29, , 2018

The District Municipality of Muskoka is undertaking an addendum to the 2014 Class Environmental Assessment (Schedule C) for servicing in the Town of Huntsville. The pending amendment proposes a relocation of the current Golden Pheasant Wastewater Treatment Plant (WWTP) outfall from the mouth of the Muskoka River to the east/central basin of Fairy Lake. Additionally, it is proposed that the current Golden Pheasant WWTP outfall pipe be repurposed as the conveyance forcemain between the anticipated Mountview Sewage Pumping Station and Golden Pheasant WWTP. The Purpose The purpose of the Public Information Centre (PIC) is to present information on the addendum and collect input from community members and other stakeholders as part

• f the Class Environmental Assessment (Class EA) and consultation process.

Your Role We invite you to ask questions, raise your concerns and provide comments. All comments will become part of the formal Record of Consultation for the addendum.

PURPOSE

1989 Class Environmental Assessment

• Developed to address long term Town of Huntsville wastewater servicing

and management

• Preferred Solution involved a two-phase approach

2014 Class Environmental Assessment

• Revisited the 1989 Class EA for validation of the Preferred Solution
• Outcome to continue with implementation of Phase 2
• Three Public Information Center (PIC) sessions conducted; overall positive

public input to proceed with Preferred Solution

• Endorsed by Town of Huntsville Council on April 28, 2014

BACKGROUND

PHASE 1 (Ongoing)

• Construct new Golden Pheasant Wastewater Treatment Plant (1996) and

maintain Mountview Wastewater Treatment Plant PHASE 2 (Deferred)

• Upgrade/expand Golden Pheasant Wastewater Treatment Plant
• Re-purpose Mountview Wastewater Treatment Plant to Sewage Pumping

Station with conveyance from Mountview Sewage Pumping Station to Golden Pheasant Wastewater Treatment Plant

• Decommission Mountview Wastewater Treatment Plant

MUNICIPAL CLASS EA PLANNING AND DESIGN PROCESS

An addendum is an established part of the Class EA process that allows for modifications to a project scope prior to

• implementation. The

addendum contains details of the change, considers the effects

• f the change and

mitigating measures. Only the proposed changes are open for review under the Class EA addendum.

CONVEYANCE & OUTFALL ALTERNATIVE Proposed Conveyance/Outfall EA Addendum to 2014 Class EA Conveyance

• Convert existing Golden Pheasant Wastewater Treatment

Plant outfall pipe to a conveyance forcemain (via slip pipe technology)

• Utilizes 2014 Preferred Solution: Option 1 routing

Outfall

• Install new outfall from Golden Pheasant Wastewater

Treatment Plant into east/central basin of Fairy Lake

ALTERNATIVE CONVEYANCE & OUTFALL ALIGNMENT

Blue circle indicates Fairyview WTP intake protection zone Proposed New Outfall Location Fairyview WTP Golden Pheasant WWTP

Open cut forcemain installation

Mountview WWTP

Slip line forcemain installation

Existing Golden Pheasant WWTP Outfall

PROPOSED OUTFALL CONSIDERATIONS

Proposed Outfall Location Mountview WWTP Outfall Golden Pheasant WWTP Outfall Blue circle indicates Fairyview WTP intake protection zone Gray areas indicate properties with municipal water supplies Blue areas indicate properties with private water supplies including waterfront homes and cottages

EFFECTS OF PROPOSED ALTERNATIVE

Advantages

 Key step in decommissioning Mountview WWTP  Previously identified in 1989 Class EA  Gravity flow (lower energy cost than pumping to existing outfall)  Maintains regulated standards for water quality  Dispersion modelling conducted by GHD and Hutchinson

Environmental Sciences Ltd. Advantages

 Utilizes 2014 Preferred Solution Option 1 routing  Reduced overall open trench construction (Highway 60)  Results in $1,000,000 in savings compared to 2014 Class EA

Preferred Solution

 No increase in residential construction disturbance  Synchronization of DMM/Town of Huntsville road works projects

New Golden Pheasant WWTP Outfall Conveyance/Forcemain Routing

• Intensive numerical modelling techniques; technical review

provided by Hutchinson Environmental Sciences Ltd.

• Based on very high quality effluent from Golden Pheasant

WWTP

• Conducted to predict the effects of the discharge at the

proposed Golden Pheasant WWTP outfall location; water quality, extent of the mixing zone, thermal/ice regime

• Mixing zone at 1% concentration does not interact with 1-

kilometer radius Intake Protection Zone (IPZ-1) or shoreline

• Safe-ice thickness (for walking) maintained; duration of ice

cover reduced by 8 days in April (in typical year)

• 6 centimeter reduction in maximum ice thickness (in typical

year) at outfall location Fairy Lake Dispersion Modelling

Fairy Lake Dispersion Modelling – Maximum Extent of Mixing Zone

• Typical and “worst-case” seasonal scenarios considered; Golden Pheasant

WWTP average and peak day flow conditions

• Maximum extent of mixing zone defined by “worst-case: winter” scenario

with long-term future (greater than 20-year planning period) peak day flow

• Mixing zone to 1% concentration does not interact with IPZ-1 or shoreline

Bottom Layer Surface Layer

Fairy Lake Dispersion Modelling – Ice Thickness Profiles (Typical Year)

At location of proposed outfall Difference in Maximum Ice Thickness: 6 cm Difference in Daily Ice Thickness Maximum: 34 cm Average: 10 cm Ice Cover Duration: 8 fewer days

• 1. This project significantly reduces the environmental

footprint on the Muskoka Watershed.

• 2. The reduction from two outfalls to one at a new

location in Fairly Lake has no adverse environmental impacts.

• 3. The proposed plans meet all Provincial regulations

as well as the upcoming Federal regulations.

• 4. The Capital project cost savings will be a minimum
• f $1,000,000.
• 5. The closure of Mountview Wastewater Treatment

Plant and consolidation with the Golden Pheasant Wastewater Treatment Plant will result in significant

• perational and energy savings.

Summary of Outcomes

Sewage Works Improvements Town of Huntsville Mountview Wastewater Treatment Plant to Golden Pheasant Wastewater Treatment Plant Conveyance Strategy

Public Information Centre (PIC)

November r 29, , 2018