Waste Water Treatment Plant Location Options Presented by: Ben - - PowerPoint PPT Presentation

Waste Water Treatment Plant Location Options

Presented by: Ben Greenough, S uperintendent of Public Works Date: April 3, 2017 In Camera Meeting

S ewer S tudy Review

2010 S

ewage Treatment and Disposal Feasibility S tudy

2013 Village/ S

kidegate Band Joint S ewage Treatment Concept Design S tudy

Existing S ewer S ystem

Existing S ewer S ystem

 Five pumping stations including the outfall

pumping station

 The collection system comprises 150, 200 and 250

mm PVC pipe

 1.2 km outfall discharges into bearskin bay

• approx. 20 m depth

 403 residential and commercial service

connections

 Does not provide sewer service to parts of the

municipality

Outfall

 The outfall at Pumping S

tation No. 5 discharges sewage through an approx. 1200 m long 200 mm HDPE S eries 45 outfall

 The pipe is buried in a trench to j ust below

the low tide mark and it then continues on the sea bottom to terminate at a depth of 20 m below low water

Treatment Plant S iting Criteria

 S

hould be isolated from residential development and public use areas - ideally within industrial or agricultural zoned land

 Based on a “ small footprint” type of treatment plant the

useable portion of the site should be about 0.11 ha in size for a long term population of 3,000; however, if a 30 m buffer area around the treatment units is added, the area requirement increases to 0.86 ha

 Long detention treatment such as aerated lagoons require

considerably more area – a minimum of 6.0 ha for 3,000 people, including a 30 m buffer zone

Treatment Plant S iting Criteria

 To minimize pumping, the site should be near sea level  The outfall must be located in an area that provides

good integration of the effluent into the seawater mass

 The outfall location must minimize impact on fisheries

resources and recreational use of the water

 S

iting must consider the potential for odor and noise nuisance on the nearest residential or public use area

 The site must not impact archaeological sites

Treatment Plant Concept Design

For the purpose of this feasibility study, it has been assumed that a small site may be acquired for a Village owned treatment plant. A “ small footprint” S equencing Batch Reactor technology has been selected for the treatment plant.

Treatment Plant Concept Design

Initial stage (1,250 people) capital and

• peration and maintenance (O&M) costs are

detailed in Appendix 3 and summarized as follows:

 Capital Cost $4,550,000 (2010 $)  O&M Cost $96,500/ year (2010 $)

Treatment Plant S ite Options

Option 1: S mith Pt Option 2: Central Area Option 3: S kidegate Landing W Option 4: S kidegate Landing E

Treatment Plant S ite Options

1.S

mith Point Area

2.Central Area 3.S

kidegate Landing West Area

4.S

kidegate Landing East Area

5.Joint treatment and disposal with

the S kidegate Band Council

S mith Point Area

PROS



The required extension of the sewer system is minimum and the existing

• utfall can be used



Existing Pump S tation No. 5 can be used to pump sewage to the treatment plant; however, an effluent pump station, and a section of land outfall would be needed at the treatment site to connect to the existing 200 mm marine

• utfall

CONS



Finding a site that is sufficiently large to provide for even a “ small footprint” treatment technology



VQC does not own property in this area



Not in an industrial or agricultural zoned location



Potential for odor, noise and nuisance on the nearest residential and public use areas

S mith Point Area

Central Area (Boat Launch)

PROS



Existing Pump S tation No. 5 can be re-used along with a 200 mm forcemain extension to the treatment plant



The existing outfall at S mith Point can be used by pumping the treatment plant effluent in a 200 mm land section of outfall that is placed in the influent force main trench



VQC owns property In this location

CONS



Finding a site that is sufficiently large to provide for even a “ small footprint” treatment technology



The sewage collection system must be extended about 1.2 km to service a site in the Central Area



Not in an industrial or agricultural zoned location



Potential for odor, noise and nuisance on the nearest residential and public use areas

Central Area (Boat Launch)

S kidegate Landing West Area

PROS



A sit e near Haida Point is assumed and would allow for a new out fall t o be const ruct ed near Haida Point t o a 30 m dept h in S kidegat e Inlet



The exist ing out fall would revert t o an emergency overflow st at us for Pump S t at ion No. 5



The t reat ment plant sit e is assumed t o be at a high enough elevat ion t o allow gravit y discharge of effluent t o t he out fall



S it e would allow for sewer connect ion for maj orit y of municipalit y and open up propert y for pot ent ial development CONS



The propert y t hat was viewed at t his t ime has since been sold and VQC does not own any propert y in t he area



Finding a sit e t hat is sufficient ly large t o provide for even a “ small foot print ” t reat ment t echnology



Not in an indust rial or agricult ural zoned locat ion



Pump S t at ion No. 5 would be fit t ed wit h new pumps and a 200 mm forcemain will ext end 3.1 km from Pump S t at ion No. 5 t o t he t reat ment plant sit e



Pot ent ial for odor, noise and nuisance on t he nearest resident ial and public use areas

S kidegate Landing West Area

S kidegate Landing East Area

PROS



A new outfall would be constructed near Image Point to discharge into 30 m of water in S kidegate Inlet



The treatment plant site is assumed to be at a high enough elevation to allow gravity discharge of effluent to the outfall



S ite would allow for sewer connection for maj ority of municipality and open up property for potential development



The site is zone industrial CONS



Finding a site that is sufficiently large to provide for even a “ small footprint” treatment technology



VQC does not own property in this area



S imilar to Option 3, Pump S tation No. 5 will be fitted with new pumps and a new 200 mm forcemain will extend 4.2 km to discharge to the treatment plant

S kidegate Landing East Area

Joint Treatment With S kidegate

Joint Treatment With S kidegate

 In 2013, VQC engineers, Opus Dayton & Knight,

worked with the S kidegate Band’s Engineers to come up with a study on how to connect VQC’s sewer system with the S kidegate WWTP

 The S

tudy looked at:

 S

everal options on how to connect the two systems

 Required upgrades to S

kidegate’ s WWTP to handle the extra flow from VQC

 Required upgrades to S

kidegate’ s outfall

Joint Treatment With S kidegate Conveyance system options

Joint Treatment With S kidegate: S kidegate WWTP Upgrades

 The current WWTP is designed for a population of 1,250

• people. This would need to be upgraded to support a

population of 2,400 people and accommodate growth in both communities The proposed upgrades include:

 A new cement t ank, wit h aerat ion blowers  A st and by generat or t o accommodat e t he expansion  A well t o accommodat e a wat er service  A headworks building wit h mechanical screen and flow

measurement equipment

Joint Treatment With S kidegate: S kidegate WWTP Upgrades

Joint Treatment With S kidegate: New Outfall

 A new outfall would be needed to service the design

population of 2,400, as the existing marine outfall only has adequate capacity for 1,700 people

 The Option 3 and 4 conveyance system would require a

new outfall to be located offshore from the sewage treatment plant

 The 200 mm outfall is marginally undersized for the design

flow, so if a new outfall is selected, then it would be wise to install a 250 mm pipe because the cost difference is small while capacity would be substantially increased allowing for growth

Joint Treatment With S kidegate: New Outfall

Joint Treatment With S kidegate: Overview

Joint Treatment With S kidegate: Considerations

An agreement between VQC and the S kidegate Band Council would have to be negotiated and include:

 Ownership and cost sharing for the sewage

conveyance system, both existing and new works

 Cost sharing for the existing treatment plant and the

expanded treatment plant, assuming Band ownership

 Cost sharing for the new outfall, assuming Band

• wnership

 Design and construction responsibility for new works

Joint Treatment With S kidegate: Considerations

S

ewage flow criteria

S

ewage quality criteria

VQC and S

BC responsibility for Permits, Approvals, etc.

And so on…

Revised Estimates (2017 $)

Option Study Estimate 2017 estimate 1. S mith Point $5,699,000 $6,838,800 2. Central Area $6,305,000 $7,566,000 3. S kidegate Landing West $7,158,000 $8,589,600 4. S kidegate Landing East $7,803,000 $9,363,600 5. Joint Treatment with S kidegate Band $11,800,000 $13,216,000

*added 20% to 2010 Study estimates 1 to 4, and 12% to 2013 Study estimate 5 to account for years of inflation

Other Considerations: S ewer service Hook-ups

Other Considerations: S ewer service Hook-ups

 Approximately 60 sewer service connections are

not on the existing system

 A gravity collection system and pumping stations

would need to be installed to include them

 No pricing was completed on this aspect  Could add $3 to $4 million dollars in expense, but

more engineering is required to develop an estimate

Other considerations: Water S ystem Extension

 If construction on a sewer main is going to

happen, Council should consider extending the water system at the same time

 A chlorine booster station would be required, and

possibly another reservoir

 A quote of $1,191,750 to extend the Water Main

to S kidegate landing was developed in 2009

 More engineering would be required to develop a

more comprehensive and updated cost estimate

Next S teps: Decide on a Location

Council will need to make a decision on where to locate a Waste Water Treatment facility:

This must include public consultation Archeological assessment may be required May need to look at purchasing or expropriating

property depending on the decision

Next S teps: Engineering

 After a location is decided upon engineers

can then develop a design for a system

 Treatment options can be reviewed at that

time

 Grant Funding will most likely be required

to complete this stage

 Multiple permits will be required for this

proj ect

Next S teps: Construction

 After the design is complete and permits are

• btained, construction can begin

 Multiple funding sources will be required for this  Construction would be completed in several

phases

 This proj ect will span several years (for example

the Honna Water Treatment Plant proj ect took 10 years from conception to completion)