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PRESENTATION OBJECTIVES
1. Provide a background summary some of the issues surrounding the current treatment plant;
3. Other relevant information.
2. Describe the results of the 2005 Strategic Review and other related studies undertaken by the RDOS; and
Sewage Treatment Plant Backgrounder
• Constructed in 1978 to process about 750 cubic metres of wastewater daily
• Comprised of an oxidation ditch, a clarifier, sludge drying beds, and infiltration basins
SecondaryClarifier
Waste Activated Sludge (WAS)
Oxidation Ditch
Ground Disposal
Sludge Drying Beds(Sludge Dewatering)
Landfill Disposal of Dried Sludge
EffluentRaw
Wastewater
Coarse BarScreen
Return Activated Sludge (RAS)
Effluent Pump
Mechanical Aeration Device
Clarifier capacity
exceeded
Sludge drying beds create
odours
Oxidation ditch at capacity
• In the early ’90s, a multi-family housing complex was built next to the plant
• By the late ’90s flows were reaching 900 cubic metres per day andcapacity concerns were being expressed
• In 2005, proposed developments was expected to increase wastewater flow to 1,100 cubic metres per day
• Due to growth, by 2025 flows could reach 1,500 cubic metres per day
0
100
200
300
400
500
600
700
800
900
1,000
Nov-03
Dec-03
Jan-0
4Feb
-04Mar-0
4Apr-0
4May-0
4
Jun-04
Jul-0
4Aug
-04Sep-0
4Oct-
04Nov
-04D
aily
Flo
w (m
3 /day
)
Measured FlowAverage Annual Daily FlowClarifier Hydraulic Capacity
Theoretical capacity exceeded during summer
Sewage Treatment Plant Backgrounder• To address near term capacity issues, a Salsnes fine screen filter was installed in 2005 to provide a short-term capacity fix
RawWastewater
SecondaryClarifier
Waste Activated Sludge (WAS)
Oxidation Ditch
Ground Disposal
Sludge Drying Beds(Sludge Dewatering)
Landfill Disposal of Dried Sludge
Effluent
Coarse BarScreen
Return Activated Sludge (RAS)
Effluent Pump
Mechanical Aeration Device
SalsnesFilter
Raw
Was
tew
ater
Dewatered ScreeningsTo Landfill
• The 0.5mm screen reduces the organic load to the bioreactor and solids loading to secondary clarifier • No change to odour generation associated with sludge drying beds
Okanagan River
Creek
Existing System
Shuttleworth
Okangan Falls STP and Effluent Pump Station
Capacity of infiltration basins used for effluent disposal is estimated to be 800 m3/day
Johnson Lake
Johnson Lake
Okanagan Falls Sewage Treatment Plant Strategic Review Study
Objectives Of The 2005 Study
Work with the Public Advisory Committee (PAC) to develop servicing options for the Okanagan Falls area;
Recommend an upgrade scenario for the Okanagan Falls Sewage Treatment Plant.
Develop a servicing concept for Kaleden and Skaha Estates; and
Four treatment plant sites evaluated
Upgrade existing plant
New plant downstream of existing near
feed lot
New plant near mill
New plant at infiltration site
Upgrade Existing STP with Oxidation Ditch, Activated Sludge or BNR Process
•Very close to housing
•BNR upgrade could allow for river discharge
•Activated sludge & oxidation ditch options rely on RI Disposal & effluent pumping
DISADVANTAGES
ADVANTAGES
•All options provide good access to agricultural land for effluent reuse
•Access requires passing school & res.
•No land cost
•Limited site size –future constraints
Move STP to RI Site –Upgrade to Oxidation Ditch,
Activated Sludge or RBC Process
•Potential land-use conflict with vineyards
•Low population density = low risk of public impact
•All treatment options rely on RI Disposal & effluent pumping
DISADVANTAGES
ADVANTAGES
•All options provide good access to agricultural land for effluent reuse
•Options require high-lift wastewater pump – high consequence of forcemain failure
•Close to RI basins
•Does not require land purchase
Move STP to WeyerhauserSite – Upgrade to Activated
Sludge or RBC Process
•Close to community water supply well
•STP compatible with industrial land-use
•All treatment options rely on RI Disposal & effluent pumping
DISADVANTAGES
ADVANTAGES
•All options provide good access to agricultural land for effluent reuse
•Options require high-lift wastewater pump – high consequence of forcemain failure
•Close to RI basins
•Land lease or purchase is required
Move STP to Feed Lot Site Downstream of Existing STP – Upgrade to BNR Process
•Land lease or purchase is required
•Existing STP and infiltration basin could be de-commissioned
•Requires ALR exclusion and OCP amendment
DISADVANTAGES
ADVANTAGES
•Good access to agricultural land for effluent reuse
•Existing gravity main would have to be extended
•Effluent could be discharged to river
•Low population density
Decision Matrix with Criteria and Assessment Data
Weighting
Category Decision Criteria
By
Gro
up
By
Crit
eria
Opt
ion
1: O
xida
tion
Ditc
h at
Exi
stin
g ST
P
Opt
ion
2: O
xida
tion
Ditc
h at
RI S
ite
Opt
ion
3: A
ctiv
ated
Sl
udge
at E
xist
ing
STP
Opt
ion
4: A
ctiv
ated
Sl
udge
at R
I Site
Opt
ion
5: A
ctiv
ated
Sl
udge
Nr
Wey
erha
user
Opt
ion
6: B
NR
(T
ertia
ry) P
lant
at
Exi
stin
g ST
P
Opt
ion
7: B
NR
(T
ertia
ry) D
/S o
f E
xist
ing
STP
Opt
ion
8: F
ixed
Fi
lm (R
BC
) at R
I Si
te
Opt
ion
9: F
ixed
Fi
lm (R
BC
) Nr
Wey
erha
user
Opt
ion
10: P
rim
ary
at E
xist
ing
STP
&
Seco
ndar
y at
RI S
ite
Financial Life-Cycle Costs 0.250 1.00 8.4 8.8 9.9 10.3 10.5 10.6 12.0 9.2 9.4 9.8
Reliability 0.28 99.9 99.9 99.99 99.9 99.9 99.999 99.999 99.9 99.9 99.9
Future Flexibility/Expansion Provision 0.25 Adequate Good Good Good Good Very Good Very Good Adequate Adequate Adequate
Effluent Quality 0.12 2ndary 2ndary 2ndary 2ndary 2ndary Tertiary Tertiary 2ndary 2ndary 2ndary
Water Re-Use Potential 0.11 Yes Limited Yes Yes Yes Yes Yes Limited Yes Limited
Operational Ease (Required Staff) 0.10 1 PT 1 PT 1 FT 1 FT 1 FT 1 FT 1 FT 1 PT 1 PT 1 PT
Method for Residuals Disposal 0.0081 Compost Compost Compost Compost Compost Compost Compost Compost Compost Compost
Technical
Site Access
0.263
0.050 Constrained Good Constrained Good Good Constrained Good Good Good Constrained
Habitat Impacts 0.50 Neutral Neutral Neutral Neutral Neutral Neutral Positive Neutral Neutral Neutral Environmental Emissions
0.188 0.50 Neutral Neutral Neutral Neutral Neutral Neutral Neutral Neutral Neutral Neutral
Health Risks 0.22 Low Low Low Low Low Low Low Low Low Low
Odour Levels 0.22 Frequent Frequent Rare Rare Rare Rare Rare Occasional Occasional Occasional
Potential for Public Conflicts (Risk) 0.19 High Moderate High Moderate Moderate High Low Moderate Moderate High
Economic Diversification 0.15 Neutral Neutral Neutral Neutral Neutral Good Good Neutral Neutral Neutral
Noise Levels 0.11 Frequent Frequent Occasional Occasional Occasional Occasional Occasional Occasional Occasional Occasional
Compatibility with Surroundings 0.074 Negative Negative Negative Negative Neutral Neutral Neutral Negative Neutral Negative
Social
Aesthetics
0.300
0.037 Negative Neutral Negative Neutral Neutral Neutral Neutral Neutral Neutral Neutral
DECISION SCORE 0.092 0.101 0.096 0.096 0.097 0.114 0.114 0.099 0.100 0.092
SCORING RANK 2 1 1 3
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
0.130
0.140
7.) B
NR (T
ertia
ry) D
/S o
f Exis
ting
STP
6.) B
NR (T
ertia
ry) P
lant
at E
xistin
g ST
P2.
) Oxid
atio
n D
itch
at R
I Site
9.) F
ixed
Film
(RBC
) Nr W
eyer
haus
er8.
) Fixe
d Fi
lm (R
BC) a
t RI S
ite8.
) Fixe
d Fi
lm (R
BC) a
t RI S
ite
5.) A
ctiva
ted
Slud
ge N
r Wey
erha
user
4.) A
ctiva
ted
Slud
ge a
t RI S
ite
3.) A
ctiva
ted
Slud
ge a
t Exis
ting
STP
1.) O
xidat
ion
Ditc
h at
Exis
ting
STP
Dec
isio
n Sc
ore
FINANCIALENVIRONMENTALTECHNICALSOCIAL
(2005 $) Rank
3,247,000 8,390,000 103,637,000 8,780,000 93,587,000 9,940,000 5
3,987,000 10,340,000 44,197,000 10,540,000 34,067,000 10,610,000 25,587,000 12,040,000 14,087,000 9,230,000 84,297,000 9,420,000 73,367,000 9,790,000 6
STP Capital Cost (2005 $)
Life-Cycle Cost
Option 8: Fixed Film (RBC) at RI SiteOption 9: Fixed Film (RBC) Nr WeyerhauserOption 10: Primary at Existing STP & Secondary at RI Site
Option 4: Activated Sludge at RI SiteOption 5: Activated Sludge Nr WeyerhauserOption 6: BNR (Tertiary) Plant at Existing STPOption 7: BNR (Tertiary) D/S of Existing STP
Option 1: Oxidation Ditch at Existing STPOption 2: Oxidation Ditch at RI SiteOption 3: Activated Sludge at Existing STP
Option
• Due to weighting of criteria, preferred option not the lowest cost option
• Results of the options assessment were presented to the public by means of a newsletter and open house
• A mail-in survey was used gauge public support
In 2005, annual cost to upgrade plant amounted to $349 per household –this cost will need to be updated
Concerning Kaleden & Skaha Estates…
!M
!M
!M0 400 800200Meters
4
Legend
!M Future Pumpstation
Future Sanitary
Gravity
Forcemain
Proposed Future Kaleden Sewerage
System
Proposed KaledenLakeshore
Sewerage Area
Proposed Kaleden Bench Sewerage Area
Forcemain to Skaha Estates
SkahaLake
!M
!M
!M
0 190 38095Meters
4 Legend
!M Future Pumpstation
Future Sanitary
Gravity
Forcemain
Proposed SkahaEstates
Sewerage Area
Proposed Future Skaha Estates
Sewerage System
Forcemainfrom Kaleden
Forcemain to Existing
Okanagan Falls Sewer
System
SkahaLake
• The relatively high costs and uncertain impacts on on Skaha Lake did not support sewering these communities at the time of the Strategic Review
• Therefore, consideration of upgrades to the Okanagan Falls Sewage Treatment Plant did not include provision for Kaleden and Skaha Estates
0 1,500 3,000750Meters
4
SkahaLake
Skaha Lake
Kaleden
Skaha Estates
Okanagan Falls Sewerage Area
• A monitoring program for SkahaLake was proposed in the Strategic Review to detect impacts of septic fields
• Sewering could be triggered by local support or identification of any impacts to Skaha Lake
• Follow-up options assessment for Kaleden & Skaha Estates completed July, 2007
• A survey was used gauge public support
Recommended option was to pump wastewater to Okanagan Falls treatment plant
Annualized cost for Kaleden & Skaha Estates $610 and $560 per household – higher than Okanagan Falls because it also includes pipes and pumps
Recommendation supported by public meetings and informal survey
In 2007/2008, RDOS was able to acquire and rezoned, a parcel of land adjacent to Okanagan River, near the KVR crossing
Potential for partnering with Ducks Unlimited to provide for wetland enhancement has been pursued and is a possibility
The Latest Wrinkle - Gallagher Lake Servicing
• A sewer feasibility study for Gallagher Lake was completed in 2007
Gallagher Lake Area
Future treatment plant site
• Capital costs are high and servicing is only feasible if the treatment plant cost is shared with Okanagan Indian Band (OIB) or potentially Okanagan Falls
Next Steps
• Are there any other considerations or options that should be considered? Does the AC support the current approach?
• Update Okanagan Falls treatment plant plan, incorporating:
1) Any new considerations/options identified by AC;
2) New treatment plant site;
3) Allowance for servicing Kaleden & Skaha Estates;
4) Allowance for Gallagher Lake area, if appropriate;
5) Assessment of effluent reuse demand (agricultural irrigation, etc.);
6) Assessment of habitat (wetland) enhancement options;
7) Design criteria that addresses potential conflicts (ie, odour & aesthetics);
8) Design criteria that minimizes carbon footprint (energy efficiency, heat recovery, etc.); and
9) Conceptual site plan and costing.