Algae Event
June 1, 2012
Lorne Park Water
Treatment Plant
Overview
The Storm and the Algae
The Equipment Damage
The Recovery
The Repairs
The Impact on the Membranes
Water Treatment Capacity
Lakeview WTP
1150 ML/d (800 ML/d membranes)
Lorne Park WTP
500 ML/d (380 ML/d membranes)
Lorne Park Treatment Processes
GAC Filters
Intake Coagulation Flocculation Sedimentation
Coagulant Low Lift
Pumping Station
GAC contactors
(retrofitted filters)
New Low Lift Pumps
and Fine Screens
Membrane
Equalization Tanks
(ex. flocculation
Tanks)
New Membrane Filtration
(retrofitted Sedimentation
tanks)
Conventional / UV Plant (120 ML/d)
Membrane/ UVAOP/ GAC Plant (380 ML/d)
Reservoir
High Lift PS UV
Sodium
Hypochlorite
UV
Zone 1
Zone 2
Membranes
380 ML/d capacity
16 trains
7800 individual modules
Warranty based on:
influent 1mm screening,
coagulant type (among other conditions)
The Storm
June 1st, 2012
Rain: 37.4 mm
Wind: 59 km/h (East)
Turbidity
1 to 60 NTU is common
during storms
Long-stringy Algae
30 ntu
Raw Water Turbidity Trend
Standard Methods:
Filter-clogging
algae
Algae Coating
Travelling Screen Damage
1 mm travelling screens
Large differential caused damage of baskets
Screens couldn’t rotate
algae passed around bent screens
Low Lift Pump Basket Damage
Basket coated in
algae
Pump taken out of
service
11 p.m. to fully
understand extent of
damage
The Solution
Several attempts to
get 1 mm screened
water to membranes
Conventional and
membrane plants are
hydraulically
separated by 1.5 m
Lorne Park Treatment Processes
GAC Filters
Intake Coagulation Flocculation Sedimentation
Coagulant Low Lift
Pumping Station
GAC contactors
(retrofitted filters)
New Low Lift Pumps
and Fine Screens
Membrane
Equalization Tanks
(ex. flocculation
Tanks)
New Membrane Filtration
(retrofitted Sedimentation
tanks)
Conventional / UV Plant (120 ML/d)
Membrane/ UVAOP/ GAC Plant (380 ML/d)
Reservoir
High Lift PS UV
Sodium
Hypochlorite
UV
Zone 1
Zone 2
X
Fixing the Flow Rate Interconnect
valve approx. 30% open
Reprogram SCADA
60 ML/d using 4 Membrane Trains
Switch from 1 mm to 10 mm screens
June 1
The Repairs
Repair crew consolidated undamaged baskets into one screen
7 days for one screen
8 weeks to repair second screen
27 damaged baskets in total
The Membranes
3240 modules
exposed to the
unscreened algae for
several hours
2160 modules
exposed to 10 mm
screened water with
coagulant for 7 days
Impact on the Membranes
Algae
Event Chlorine
Clean
Citric
Clean
Acknowledgements
Ontario Clean Water Agency
Consultants
AECOM, GENIVAR
Contractors
Kenaidan, Maple Reinders
Equipment Suppliers
GE Water & Process Technologies
(membranes)
Siemens (travelling screens)