Basement Flood Protection - Toronto Subsidy Program

City of Toronto notes that basements can flood for many reasons. While the City is working to make improvements to its complex system of underground pipes, sewers and catchbasins, these improvements alone cannot completely protect a home from basement flooding. With the increasingly frequent and severe weather, it is essential that homeowners take the appropriate action to reduce the risk of basement flooding on their own private property. Those who isolate their home from the City's sewer system can significantly reduce the risk of basement flooding.

To assist homeowners, the City offers owners of single-family, duplex and triplex residential homes a financial subsidy of up to $3,200 per property to install flood protection devices including a backwater valve, a sump pump, and pipe severance and capping of the home's storm sewer or external weeping tile connection.

Work that is eligible:
Each property owner is required to have a Plumbing Contractor, licenced by the city of Toronto, carry out a site assessment to determine the suitability of isolating their property from the City's sewer system. Contact Municipal Licensing & Standards at 416-392-6700 to verify that your contractor has the appropriate City of Toronto plumbing licenses. The following items and works are eligible for a subsidy after proper installation:

A: Backwater valve
In consultation with a Plumbing Contractor or Drain Contractor licensed by the City of Toronto, homeowners may determine that a backwater valve on the sanitary sewage and/or stormwater connection could provide sufficient basement flooding protection.
Available subsidy = 80% of the invoiced cost up to a maximum of $1,250 including eligible labour, materials, permit and taxes.

B: Sump pump
In consultation with a Plumber Contractor and/or a Building Renovator with an endorsement for concrete work licensed by the City of Toronto, homeowners may determine that a sump pump is required to manage the water normally collected by footing weeping tiles that drain to the sanitary, storm or combined sewer. Sump pumps need power to operate, so consider installing a back-up power source.
Available subsidy = 80% of the invoiced cost up to a maximum of $1,750 including labour, materials and taxes.

C: Backwater valve + sump pump
Homeowners may determine that both a backwater valve and a sump pump are required (see details in previous section A and B). Available subsidy = 80% of the invoiced cost up to a maximum of $2,800 including eligible labour, materials, permit and taxes.
Backwater valves and sump pumps need to be inspected and maintained to ensure optimal performance.

D: Pipe severance and capping
In consultation with a Plumber Contractor or Drain Contractor licensed by the City of Toronto, homeowners may determine that disconnecting foundation drains (weeping tiles) from the City's sewer system by severing and capping the underground storm sewer connection pipe is also required to protect the home from basement flooding.
Available subsidy = 80% of the invoiced cost up to a maximum of $400 including eligible labour, materials and taxes.
When you are applying for more than one item under the subsidy program, you cannot apply any unused funds from one item to another.

Eligibility requirements and information: The City of Toronto will determine the eligibility of properties that meet the requirements listed below:

  • The property must be registered as a single-family residential, duplex or triplex property within the City of Toronto.
  • The subsidy is available only to existing homes, not homes in the planning stages or currently under construction.
  • The property must have its eavestrough downspouts properly disconnected from the City sewer system, where possible.
  • A Plumbing Contractor or Drain Contractor currently licensed by the City of Toronto, must be hired to install a backwater valve and/or perform severance and capping.
  • A Plumber Contractor and/or a Building Renovator currently licensed by the City of Toronto must be hired to install a sump pump.
  • A building permit and an approved inspection must be obtained for backwater valve installations.
  • For properties with a parking pad instead of a driveway, all front yard paved areas must comply with the City's Zoning By-law requirements.
  • All installations must be completed before the applicant applies for the subsidy.
  • Invoice(s) must show a cost breakdown of all charges, the total amount paid and be clearly marked as "paid in full".
  • The property owner or authorized legal representative must sign and date the application form.
  • All documents must be originals. No photocopies will be accepted.
  • Applications and supporting documentation must be received by the Basement Flooding Protection Subsidy Program office within one year of the date of completion of the work, as listed on your original invoice(s).
  • Subsidies for eligible work are subject to available funding and provided on a first-come, first-served basis.
  • Subsidies are provided one time only for each eligible installation, per property, and on a no-fault basis 
Below is a list of Toronto area sewer contractors and plumbers who could assist with backflow valve installation:

North York, Toronto, ON ‎
(416) 749-1800 ‎ ·
city plumbers · back-water valve · sump pump installation · water supply line · grease trap
Ideal Plumbing & Drain  
37 Nipigon Ave, North York, ON M2M 2V7 ‎
(416) 371-7137 ‎ ·
backwater valves · sewer
"Toilet Clog | Burst Pipes | Backflow Prevention | Backwater Valve Installation | Drain repair | Installing Sump pump | Clogged Drain Repair | Blocked Drain ..." -
ON M8Z 3L2 ‎
(416) 233-6699 ‎ ·
peace of mind · floor drain · camera inspection · water meter · licensed plumber
"They gave us a very detailed estimate and completed the job in only 2 days - including digging up our basement drains, installing a backflow valve, and ..." -
New Canadian Drain & Plumbing Ltd  
Toronto, ON ‎
(416) 651-2990 ‎ ·
drainage system · weeping tiles · insulation
"Since they had to dig up a portion of our basement to complete the work, we also had them rough in a bathroom in the basement and install a backflow ..." -
Winners Plumbing & Mechanical Services 
71 Whitney Pl, Vaughan, ON L4J 6V6 ‎
(416) 906-4600 ‎
Mississauga, ON ‎
(416) 989-5757 ‎ ·
underpinning · flood · sewer
"The pleasant team of Tadek and Alex installed the sewer valve and replaced two window wells in only 2 days. Covered my floors - and outside concrete ..." -
Public Plumbing  
300 New Toronto St #14, Toronto, ON M8V 2E8 ‎
(416) 556-5658 ‎ ·
"They dug into our floors, and replaced all of the clay pipe with plastic and installed a backflow valve to prevent further problems. The city inspector ..." -
Lampert Plumbing Systems Inc  
119 Miranda Ave, Toronto, ON M6B 3W6 ‎
(416) 787-4921 ‎ ·
"New fixture and faucet installations with a two year warranty, faucet repair, toilet replacement, and Certified backflow preventer installation and ..." -
ExpressRooter Plumbing  
750 Oakdale Rd, Toronto, ON M3N 2Z4 ‎
(416) 233-2660 ‎ ·
"Called Express Rooter to have them install our New Bathtub, they dispatched Vlad to our home. Vlad, did excellent work for us, was polite and stayed ..." -
DanMac Plumbing & Drain Service Ltd  
33 Chauncey Ave, Etobicoke, ON M8Z 2Z2 ‎
(416) 237-9161 ‎ ·
"The DanMac plumber installed a cheaper model pop-up that was fused. I would have gone for a more expensive one that could have been removed but I wasn't ..." -

Aqua Tech Basement Waterproofing, Plumbing & Drain  
3 Leggett Ave, Toronto, ON M8P 1X1 ‎
(416) 300-2191 ‎ ·
"Sewer Camera Inspection; Sump Pump Installation; Grease Traps; Backflow Preventer Installation; Drain Snaking; Water Main Replacement; Sewer Backwater Valves" -

Oakville, ON ‎
(416) 876-3006 ‎ ·
Thornhill Plumber  
27 Dalmeny Rd, Thornhill, ON L3T 1L9 ‎
(416) 371-7137 ‎ ·
"Toilet Clog | Burst Pipes | Backflow Prevention | Backwater Valve Installation | Drain repair | Installing Sump pump | Clogged Drain Repair | Blocked Drain ..." -
Konkle Plumbing & Heating  
5308 Philp Rd, Beamsville, ON L0R 1B2 ‎
(905) 563-4847 ‎ ·
AWS Irrigation Management Inc  
304 Stone Rd W, Guelph, ON N1G 4V9 ‎
(519) 826-5752 ‎ ·
lawn sprinkler system · drip
"Automatic lawn sprinkler systems, drip irrigation, backflow valves and directional drilling is our area of expertise; we install, repair, test, ..." -
Watts Water Technologies (Canada) Inc 
5435 North Service Rd, Burlington, ON L7L 5H7 ‎
(905) 332-4090 ‎ ·
"Introducing the Dead Level™ Presloped Trench Drain System—An innovative drain system designed to reduce installation time & eliminate floating and ..." -
Metro Infrared Inspections  
10 Nepean Pl, Brampton, ON L6S 5Y8 ‎
(905) 260-9335 ‎ ·
"grease trap installations; sump pump repair & installation; sump pump backflow valve service; water main repair or replacement; lead water main line ..." -
Drain Cleaning Services Toronto Plumbing Drain  
 125 Parkway Forest Dr, North York, ON M2J 1L9 ‎
(416) 371-7137 ‎ ·
"Toilet Clog | Burst Pipes | Backflow Prevention | Backwater Valve Installation | Drain repair | Installing Sump pump | Clogged Drain Repair | Blocked Drain ..." -
455 Horner, Etobicoke, ON M8W 4W9 ‎
(416) 503-4000 ‎ ·
"Plumbing Specialties; Pressure Regulators; Relief Valves; Strainers; Tempering Valves; Water Heater Installation Products. Backflow Prevention" -
Ideal Plumbing & Drain  
125 Parkway Forest Dr, Toronto, ON M2J 1L9 ‎
(416) 371-7137 ‎ ·
"Toilet Clog | Burst Pipes | Backflow Prevention | Backwater Valve Installation | Drain repair | Installing Sump pump | Clogged Drain Repair | Blocked Drain ..." -

Flood Risk Reduction - Harris County Flood Insurance

Each year, the Harris County Flood Control District submits an annual 5-year Capital Improvement Program (CIP) to Commissioners Court for approval. The "5-year" refers to a sliding window that constantly advances 5-years into the future as each year passes. This 5-year window encompasses all of the current and estimated capital improvement activities the District will implement throughout Harris County. Implementing projects is one of the three key facets of the District's mission.

In 2001, an innovative approach to funding the District's future capital project needs was adopted by the Harris County Commissioners Court that provides funding at levels four to five times higher than any time in the past. This new funding approach enables an even more aggressive implementation of flood damage reduction projects across Harris County.

HCFCD Active Projects image showing both Federal partnerships and local and regional partnerships.

Current Estimated CIP
The District's current 5-year CIP for flood damage reduction projects throughout Harris County is estimated at more than $975 million, with about 20% of that reserved for project right-of-way (or land acquisition) and buyouts. The CIP also includes engineering studies, planning efforts and actual construction of identified projects.

What the CIP Buys
Some of the projects that are implemented may involve channel modifications (modifying of existing streams, bayous or tributaries), new channel construction, excavation of large stormwater detention basins, or buyout of homes that have experienced repetitive flooding or are located hopelessly deep in the regulatory floodplain.

Some of the funds allocated in the CIP go toward flood damage reduction projects implemented solely by the Harris County Flood Control District. Other CIP funds go toward flood damage reduction projects that involve federal partnerships. These partnership projects are bolstered by an influx of federal dollars, and often mean faster completion schedules.

The CIP is Regularly Adjusted
The annual 5-year CIP is "officially" visited for adjustments and updates three times annually and presented to Commissioners Court all three times. Around December of each year, the District's Operations and Maintenance budget, including the 5-year CIP, is submitted to Commissioners Court for review in anticipation of the District's new fiscal year, starting each March 1. In June of each year, Commissioners Court holds a CIP review and the District submits its 5-year CIP with any adjustments for review by the court members. In September of each year, the 5-year CIP is again submitted with any adjustments, along with the District's mid-year budget submittal for mid-year budget review by Commissioners Court.

Useful links related to Texas flood insurance:
Map Your Flood Risk -

Find floodplain maps, facts, FAQs, your flood risk profile and more.
Get Flood Insurance -
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Affordable Home Insurance  -  Save Money  -  Compare Quotes  -  Shop for Home Insurance

Kyle Peterson Insurance -
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Texas Flood Insurance -

Get Texas Flood Insurance Quotes Save On Texas Flood Insurance Now
Free Online Quotes  -  Affordable Homeowners Insurance  -  Compare Homeowners Rates Online  -  Policies From $15 / Month

Basement Flood Protection - Seattle

Seattle is home of the 'side sewer' - another term for lateral sewer, or private drain connection (PDC) for those into acronyms.  That is, the sewer that connects your home or business to the City's mainline sewer in the street.  Seattle is also home to the 'Flusher Family' .. they star in a campy info-tainment video the Side Sewer Saga that educates on sewage basics.  Gotta love Ivana Flusher ... she flushes everything she shouldn't!  I'm actually having Austin Powers flashbacks ...Ivana Flushalot!
Home showing Building Sewer (aka Side Sewer)

Seattle Public Utilities notes common sources of sewer problems:
● Tree roots can penetrate older clay pipes. Modern side sewer pipes are heavy duty, water-tight plastic which last much longer.
● Grease can contribute greatly to sewer problems. Prevent grease, fat, oil, wax and other debris from
going down the drain by scraping them into the trash. Do not put these kinds of materials into your garbage
disposal. It can cause blockages in the sewer system, which can lead to backups.
● The grade (slope) of your private side sewer can also impact how well your sewer lines function. If the slope is too gradual, you may encounter more frequent blockages. To learn about required slope for side
sewers, call 206-684-5362.
● Sometimes, private side sewers are joined with neighboring properties before they connect to the city’s
sewer main. Any unusual bends, curves or connections can lead to sewer problems. A blockage in one section of a joint or shared side sewer line can cause backups to neighboring properties.
● Under rare circumstances, heavy storm-related events can result in backups in some areas with a combined sewer/drainage system. If you suspect that extreme rainfall is causing a sewer backup, call SPU’s 24-hour emergency number at 206-386-1800.
● To learn more about the City of Seattle's Side Sewer codes, permits, registered contractors and Director's
Rules visit call 206-684-5362.

Seattle plumbing and drain contractors include:

O'Neill Plumbing  
 6056 California Ave SW, Seattle, WA, United States ‎
+1 425-455-0560 ‎ ·

Jim Dandy Sewer & Plumbing  
903 N 128th St, Seattle, WA, United States ‎
+1 206-633-1141 ‎ ·

Fox Plumbing & Heating  
7501 2nd Ave S, Seattle, WA, United States ‎
+1 206-654-4990 ‎ ·
kitchen faucet · sump pump · garbage disposal · excellent job · tankless water heater

Fischer Plumbing  
1115 NW 51st St, Seattle, WA, United States ‎
+1 206-783-4129 ‎ ·
4.212 reviews ·
water leak · water damage · furnace repair · really appreciate · sewer line

South West Plumbing  
2401 SW Alaska St, Seattle, WA, United States ‎
+1 206-932-1777 ‎ ·
sewer line · excellent customer service · heater · water leak · hot water tank

Bob Oates Sewer & Rooter  
600 W Nickerson St, Seattle, WA, United States ‎
+1 206-789-4944 ‎ ·
plumbing issues · plumbing company · garbage disposal · sewage

Raymark Plumbing & Sewer  
10710 Lake City Way NE, Seattle, WA, United States ‎
+1 206-440-9077 ‎ ·
hot water tanks · pipe bursting · local plumber · heaters

Stalwart Plumbing Inc  
618 NW 86th St, Seattle, WA, United States ‎
+1 206-784-3747 ‎ ·

Alligator Sewer & Drain  
Ballard, Seattle, WA, United States ‎
+1 206-784-3552 ‎ ·

Pioneer Plumbing & Heating  
2400 NW 80th St, Seattle, WA, United States ‎
+1 206-789-8029 ‎ ·

Basement Flood Protection - Los Angeles

During the heavy rains that are often faced in Los Angeles area, the basement flooding problems arise. There are range of options that homeowners can use to reduce their risk.  Backwater valve installation is just one of the ways in which you can do so to stop waste water from flowing back into your home from the sewer and storm water drains.  And it can save you quite a bit in the end:

Better Insurance Cover
Flooding happens.  During Los Angeles’s spring showers, it’s a regular event, and insurance companies also know it. Because of that, homeowners’ insurance for Los Angeles typically covers damage caused by only certain types of flooding. And the way insurance works, if you’re under-insured you could get back less than you need to cover a claim. A standard homeowners’ insurance policy doesn’t include cover for flood damage caused by conditions originating outside the home, which means you aren’t covered unless you take out special flood insurance protection.

Lower Premium Payments
Since flood damage insurance is a separate policy, getting the cover you need could be pretty expensive.

This is an additional premium you have to pay over and above your existing insurance. Without a backwater valve installation, either your flood damage insurer is going to hike your premiums, or your cover is going to be compromised, as noted above.

So you need comprehensive insurance that c

overs your home for every possible situation and doesn’t contain a whole list of exclusions, and getting a backwater valve installation means you eliminate one of the insurers’ favorite exclusions and non-payment tactics.

Reduce Flood Damage Costs
And then, there’s the cost of repairs. Even if you have the right insurance policies, there are hidden costs that no amount of insurance can make up for. The inconvenience of basement flooding, for example, includes having no access to your basement while you get it cleaned out and repaired. The cost of storage for whatever you can salvage while repairs are being done. The loss of items that have sentimental value, such as

Old photographs, books and music
Mementos from your children’s baptism or first day at school
Your mother’s wedding dress
All the items we typically store in the basement, which are irreplaceable / priceless

Before the Spring rains begin, check whether your backwater valve installation is in good condition, if you have one. If it needs attention or you don’t have one at all then schedule your backwater valve installation well ahead of time.

Los Angeles plumbing and backflow professional services are presented below:

Kirman Plumbing
Los Angeles, CA 90021
(800) 654-7626
Backflow Prevention Devices & Services, Plumbers, Plumbing Contractors-Commercial & Industrial

Century Rooter & Jetting Service
Serving the Los Angeles Area.
(800) 782-4744
Backflow Prevention Devices & Services, Plumbers, Heating Contractors & Specialties

Dumpster Central
Serving the Los Angeles Area.
(888) 964-9925
Backflow Prevention Devices & Services, Rubbish & Garbage Removal & Containers, Trash Hauling

Kirman Plumbing Co
Serving the Los Angeles Area.
(800) 654-7626
Backflow Prevention Devices & Services, Water Heaters, Plumbers

Roy Coto Plumbing Inc. Backflow Testing & Repairing
Serving the Los Angeles Area.
(415) 370-9001
Backflow Prevention Devices & Services, Building Contractors-Commercial & Industrial

The American Backflow Prevention Assoc
7158 Knowlton Pl, Los Angeles, CA 90045
(310) 649-4111
Backflow Prevention Devices & Services

Backflow Prevention Device Testing Service
Serving the Los Angeles Area.
(818) 240-6383
Backflow Prevention Devices & Services

Torrance Plumbing Heating & Air Conditioning
21759 S Western Ave, Torrance, CA 90501
(310) 328-4444
Backflow Prevention Devices & Services, Furnace Repair & Cleaning, Heating Equipment & Systems-Repairing

Exner Plumbing
6826 Hazeltine Ave, Van Nuys, CA 91405
(818) 784-0218
Backflow Prevention Devices & Services, Plumbing-Drain & Sewer Cleaning, Plumbers

Moe Plumbing Service Center
830 W Doran St, Glendale, CA 91203
(818) 572-4200
Backflow Prevention Devices & Services, Plumbers, Water Heaters

Backflow Apparatus & Valve Co
20435 S Susana Rd, Long Beach, CA 90810
(714) 891-5605
Backflow Prevention Devices & Services

Backflow Prevention Device
675 S Glenwood Pl, Burbank, CA 91506
(818) 240-6383
Backflow Prevention Devices & Services

FDI Voice
7606 2nd St, Downey, CA 90241
(562) 271-0505
Backflow Prevention Devices & Services

AAA Backflow Device Testing
675 S Glenwood Pl, Burbank, CA 91506
(818) 972-2495
Backflow Prevention Devices & Services

Simply Backflow Testing & Repair
PO Box 250718, Glendale, CA 91225
(818) 669-9404
Backflow Prevention Devices & Services

Acme Plumbing Supplies & Service
14819 1/2 Oxnard St, Van Nuys, CA 91411
(818) 785-8811
Backflow Prevention Devices & Services

Backflow Prevention Svc
PO Box 56, Torrance, CA 90507
(310) 316-1717
Backflow Prevention Devices & Services

Backflow Testing & Service Co
21309 Marjorie Ave, Torrance, CA 90503
(310) 316-8248

A-A Backflow Testing
2535 W 237th St, Torrance, CA 90505
(310) 530-6663

Aquacheck Backflower Prevention
940 Challenger St, Brea, CA 92821
(562) 697-8915

Atlas Backflow
1665 E 28th St, Signal Hill, CA 90755
(562) 997-4560
Backflow Prevention Devices & Services

Backflow Plumbing County Wide Discount
6845 Newcastle Ave, Reseda, CA 91335
(818) 776-0042
Backflow Prevention Devices & Services

Aquacheck Backflow Prevention Testing & Service
431 Park Industrial Dr, La Habra, CA 90631
(562) 697-8915
Backflow Prevention Devices & Services

Backflow and Fire Technology
Walker & Orange, Cypress, CA 90630
(949) 491-1401

Pete's Plumbing
13446 Ventura Blvd, Sherman Oaks, CA 91423
(818) 789-6488

Century Rooter & Jetting Service Inc.
2610 Apple Ave, Torrance, CA 90501
(310) 782-3759
Backflow Prevention Devices & Services, Plumbers, Water Heater Repair

Burwell Plumbing Co
18414 Eddy St, Northridge, CA 91325
(818) 349-8363
Backflow Prevention Devices & Services, Plumbing-Drain & Sewer Cleaning, Plumbers

Advance Plumbing
1456 E Hill St, Signal Hill, CA 90755
(562) 426-1725
Backflow Prevention Devices & Services, Plumbing-Drain & Sewer Cleaning, Plumbers

Rogers Plumbing
5721 Shirl St, Cypress, CA 90630
(714) 995-7787

Basement Flood Protection - Chicago

Chicago's long and colorful history includes troublesome tales of flooded homes filled with five feet of contaminated, bacteria-carrying water from sewer backup.  After the flood of 1997 caused hardship and property loss for some 35,000 residents of its close to three million population, city officials took action. To prevent the system from reaching maximum capacity they pursued slowing the heavy inflow of rainwater into the sewer system during the peak of the storm.

City officials installed mechanical devices called inlet restrictor valves and promoted downspout disconnection by homeowners citywide. Purchase and installation cost $75 million dollars. This was about a quarter of what traditional sewer system improvements would have cost.

A $7.8 million grant from the Federal Emergency Management Agency Hazard Mitigation Grant Program (HMGP) jumpstarted the Chicago project in 1998. Chicago Sewer Department Commissioner, said, "In every subsequent rain that we've had since the pilot program was implemented, the pilot areas have not experienced the type of flooding they normally would have."

Chicago initiated its inlet control valve system (called the "Rainblocker" program) as one facet of a multi-dimension concept.  DWM workers installed close to 200,000 inlet restrictor valves into Chicago's street catch basins, at a rate of 90 to 120 per day. When the restrictor valve is installed in the storm water catch basin in the street, the device, in essence, shrinks the pipe to funnel and regulate the water from the street to the main sewer line. During a heavy rain event, the smaller opening allows less water into the sewer system. The streets act as a temporary holding area for the rainfall. Surplus water in the system will not be forcing contaminated water back through homeowners' private lines and into the home's lowest spot - the basement. The street ponding buys time for the system to catch up.

A Work in Progress:  The city is the first to recognize flooding problems still exist. Flooded streets, a problem deemed preferable to flooded basements, are an acknowledged byproduct of the valve system because of the restricted flow of water into the sewers. In the recent rains, some residents reported only a couple of inches of water whe
re in previous storms their basements had held over a foot of water. In some instances, however, homes that had never been flooded before were flooded in this last event due to ponded runoff entering basement windows and doors.

Homeowners still experiencing back-ups can consider a backflow prevention valve.  Chicago area drain contractors are listed below.

Chicagoland Plumbing
3101 North Natchez Avenue, Chicago, IL, United States ‎
+1 773-699-7473 ‎ ·

Arco Plumbing & Heating  
206 N Cass Ave, Westmont, IL, United States ‎
+1 630-960-5950 ‎ ·
sewer cleaning · heaters

A-Archer Sewer & Plumbing  
100 N La Grange Rd, La Grange, IL, United States ‎
+1 708-579-0200 ‎ ·

Di Foggio Plumbing Prtns Inc  
3241 S Shields Ave, Chicago, IL, United States ‎
+1 312-842-1102 ‎ ·
hot water heaters · booster pumps · video inspection · garbage disposals · ejector pumps
"We are a Plumbers Union Local 130 Shop, a proud member of the Plumbing Council of Chicagoland, the Plumbing Contractors Association of Chicago and Cook ..." -

Matula Plumbing, Inc.  
2293 Westview Dr, Des Plaines, IL, United States ‎
+1 847-975-4668 ‎ ·

Marquise Plumbing and Backflow  
Naperville, IL, United States ‎
+1 630-596-9115 ‎ ·

A - Archer Sewer and Plumbing Service  
31 E Elm St, Roselle, IL, United States ‎
+1 630-980-3500 ‎ ·

Heritage Plumbing Co  
2116 Stonington Ave, Hoffman Estates, IL, United States ‎
+1 847-885-9800 ‎ ·
flood control · power rodding · sump pumps · clean outs · sewer line

Reliance Plumbing  
1848 Techny Rd, Northbrook, IL, United States ‎
+1 847-583-1858 ‎ ·
bonded and insured · hot water heaters · tankless water heater · sump pump · sewer repair
"When your home's drainage system has backflow problems, you're looking at a variety of issues in terms of your house, plumbing, and overall well-being ..." -

Basement Flood Reduction - Vancouver, BC

The Vancouver Real Estate Board notes that many residents and businesses in the Lower Mainland are located in a floodplain - close to or beside local rivers, creeks, or coastlines.

They suggest you can reduce the chances of flood damage by:

1. Reading material about flood reduction supplied by the local municipality.
2. Walking around the home after heavy rainfall to see where water is pooling. If water flows toward the home, the owner should get professional advice about directing water away from the home.
3. Cleaning gutters and downspouts.
4. Making sure the home’s drain tiles work. The basement will flood if tiles are old or plugged and need replacing.
5. Flood proofing the basement or ground floor, which involves sealing the foundation.
6. Installing backflow valves on basement floor drains, washing machine drains, toilets and sink drains.
7. Locating the storm sewer on the road. It will look like a large grate and is designed to carry storm related water runoff. If it’s plugged with leaves, the owner should phone the local municipal public works department and they will clean it.
8. Buying a sump pump and testing it so it’s ready to be used if needed during heavy rain storms.
9. Contacting the municipality to find out where sand and bags are available should a flood occur.

In Canada, flood insurance isn’t available to home owners. Other water damage may be covered by homeowner policies, including sewer backup and burst pipes, but not for overland flooding.

While a flood can happen anywhere it rains, home buyers should assess flood risks in the area where they plan to buy. Home buyers can:

1. Review floodplain maps for specific areas (Region 2 - Lower Mainland)
2. Talk to the local municipality about the risk and the history of flooding in the area.

Edenflo Pump Truck Services 604-576-5450
5470 192 St, Surrey, BC V3S 8E5
We provide hydro excavation, hydro flushing and vacuum truck services to commercial and residential customers.

Rotor Plumbers & Drainage Ltd  604-549-5048
Complete Plumbing & Heating, Sewer & Drain Cleaning Service, Camera Pipe Inspection, Hydro Pressure Jetting.

Hillcrest Plumbing & Heating 604-695-1626
212 17th Ave E, Vancouver, BC V5V 1A7
“Uncle Bill's" Hillcrest Plumbing & Heating has been serving the Lower Mainland with competitive prices
Category: Plumbers & Plumbing Contractors, Drainage Contractors

A G Woodward Drainage & Roofing Ltd 604-696-3287
Rear-5672 Victoria Dr, Vancouver, BC V5P 3W4
AG Woodward Drainage and Roofing EXPERIENCED quality...
Category: Drainage Contractors

Lew Plumbing & Heating Ltd 604-205-9436
127-2323 Boundary Rd, Vancouver, BC V5M 4V8
Lew Plumbing offers 24/7 service to Vancouver, Richmond,...

Hillcrest Plumbing & Heating 604-879-5301
3260 Main St, Vancouver, BC V5V 3M5
Simply the Best in the Lower Mainland!
$20 Off Hot Water Tank Installation

Dave M The Plumber Ltd 604-549-0350
7608 Davies St, Burnaby, BC V3N 3H4
Secondary Ph #: 778-898-5657
Category: Drainage Contractors

Brilor Construction Management 778-552-2750
Specializing in repairing leaky basements
Category: Drainage Contractors

McRae's Septic Tank Services (Vancouver) Ltd 604-695-0945
6891 MacPherson Ave, Burnaby, BC V5J 4N2
McRae's Environmental Services now offers one of the most...
Category: Drain & Sewer Cleaning, Septic Tank Cleaning

Superstar Plumbing Heating & Sprinkler Supplies Ltd 604-322-5732
6640 Fraser St, Vancouver, BC V5X 3T5
Category: Plumbers & Plumbing Contractors

Bestway Drainage Excavating & Demolition 778-881-7580
7921 120 St, Delta, BC V4C 6P6
Category: Drainage Contractors

A-1 Drainage Plumbing & Heating Ltd 604-875-6770
376 13th Ave E, Vancouver, BC V5T 2K5

Basement Flood Protection - New York

A backwater valve can help prevent sewage from flowing from the pipes back into your home during heavy rain. New York City building code requires valves for many new buildings and major renovations. The work must be done by a licensed plumber.

After installation, inspect the valve periodically to make sure it works when you need it.

NOTE: To check if a plumber or electrician holds a valid license, visit or call 311
(TTY: 212-504-4115). For any of these improvements, get quotes from multiple contractors.  Some contacts are provided below:

Jay Ell Plumbing & Heating Inc
307 7th Ave, New York, NY, United States ‎

+1 212-989-6670 ‎ ·

P J Mechanical Corporation
135 W 18th St, New York, NY, United States ‎
+1 212-243-2555 ‎ ·
heating and air conditioning systems · james pappas · control systems · profile projects · high profile

Fred Smith Plumbing & Heating
Manhattan, New York, NY, United States ‎
+1 212-744-1300 ‎ ·
4.331 reviews ·
department of buildings · quick response · licensed plumber · water treatment · roof tank

Sheet Metal Chimney
168 2nd Ave, New York, NY, United States ‎
+1 347-413-3052 ‎ ·
kitchen exhaust · flue pipe · ventilation · boiler

Central Plumbing Specialties
141 E 56th St # 1, New York, NY, United States ‎
+1 212-588-1997 ‎ ·

St Nicholas Plumbing Sewer & Drain
41 St Nicholas Terrace, New York, NY, United States ‎
+1 212-377-2867 ‎ ·

Watson's Piping & Heating Corporation
470 Convent Ave, New York, NY, United States ‎
+1 212-368-3434 ‎

Davis & Warshow
96 Spring St, New York, NY, United States ‎
+1 212-680-9000 ‎ ·

205 West End Avenue Corporation
205 W End Ave, New York, NY, United States ‎
+1 212-580-5600 ‎ ·

ABI Contracting Corporation.
4 Park Ave #11p, Manhattan, NY, United States ‎
+1 917-531-2894 ‎ ·

Are You Feeling (Un) Lucky?

Clint Eastwood inspired us all to consider risks in the Dirty Harry movies.  Everybody knows that in Russian roulette the odds of 1 in 6 are not in your favour when it comes to pulling the trigger.  Odds of 1 in 100 make some people complacent.  In general, people are at home with the really long odds of fatalities from serious events.  Some examples (see flooding highlighted):

SOURCES: - all records from 2002

1     Risk of Dying next year: Transport Accidents
Pedestrian 1 in 47,273
Pedal Cyclist 1 in 375,412
Motor Cycle Rider 1 in 89,562
Car occupant 1 in 17,625

2    Risk of Dying next year: Transport Accidents
Occupant  of pick-up truck or van 1 in 67,182
Traveling in heavy transport vehicle 1 in 631,450
Occupant  of a bus 1 in 6,696,307
Riding horse or animal drawn vehicle 1 in 244,180

3 Risk of Dying next year: Transport Accidents
While on railway train 1 in 10,283,615
Occupant of street car 1 in 71,985,305
Occupant of agricultural vehicle 1 in  1,932,491
While on water transportation 1 in 466,679
From air and space accidents 1 in 440,951

4 Risk of Dying next year: Falls
Tripping/slipping at same level 1 in 445,729
Falling from bed, chair or furniture 1 in 366,804
Falling from stairs or steps 1 in 180,188
Falling from ladder or scaffolding 1 in 709,215
Falling out of building 1 in 516,950

5    Risk of Dying next year: Struck by objects unintentionally
Hit by some object 1 in 333,265
Caught between 2 objects 1 in 2,503,837
Contact with machinery 1 in 441,628
Contact with sharp objects 1 in 2,742,297

6 Risk of Dying next year: Explosions
Unintentional firearms discharge 1 in 57,588,244
Explosion of pressurized vessels 1 in 10,664,490
Explosion of fireworks 1 in 57,588,244
Explosion of other materials 1 in 2,101,781

7 Risk of Dying next year: Animate causes
Struck by a person 1 in 11,074,662
Bitten by a dog 1 in 15,966,734
Bitten by other mammals 1 in 3,839,216
Bitten or stung by insect 1 in  22,149,325

8 Risk of Dying next year: Accidental drowning
All causes 1 in 83,534
In bath tub 1 in 818,015
In swimming pool 1 in 452,738
In natural water 1 in 217,314

9 Risk of Dying next year: Accidental threats to breathing
Suffocation in bed 1 in 565,700
Strangulation 1 in 969,499
Cave-in or falling earth 1 in 5,051,600
Food- in respiratory tract 1 in 351,577

10 Risk of Dying next year: Electricity, temperature
Electric transmission lines 1 in 2,641,663
Other electric current 1 in 894,227
Contact with hot tap water 1 in 7,198,531
Excessive  man-made heat or cold 1 in 28,784,122

11 Risk of Dying next year: Smoke, fire and flames
All causes 1 in 91,149
Uncontrolled fire in building 1 in 113,676
Controlled fire in building 1 in 8,226,892
Ignition of nightwear 1 in 22,149,325

12 Risk of Dying next year: Venomous Animals and plants
Contact with venomous snakes 1 in  95,980,407
Contact with venomous spiders 1 in 28,794,122
Contact  hornets, wasps and bees 1 in 5,332,245

13 Risk of Dying next year: Forces of Nature
All types and causes 1 in 236,211
From Lightning strikes 1 in 4,326,748
From earthquakes 1 in 9,288,426
From cataclysmic storm 1 in 4,570,498
From Floods 1 in 31,993,469
Excessive natural heat 1 in 822,689
Excessive natural cold 1 in 445,729

14 Risk of Dying next year: Poisoning and Noxious Substances
All types and causes 1 in 16,407
Gases and vapors 1 in 416,702
Alcohol 1 in 811,102
Pain relievers, anti-rheumatics etc 1 in 1,297,033
Narcotics and hallucinogens 1 in 34,843

15 Risk of dying next year: Intentional Self-Harm
All types and causes 1 in 9,096
Self -poisoning 1 in 52,487
Self-hanging, strangulation 1 in 44,559
Self-harm by firearm 1 in 16,831

16 Risk of dying next year: Assault by someone else
All types and cases 1 in 16,325
Assault by firearm 1 in 24,342
Assault by sharp object 1 in 138,834
Legal execution 1 in 4,297,630

17 Risk of dying next year: Cause known – undetermined intent
Poisoning 1 in 86,313
Hanging, strangulation 1 in 2,164,927
Firearm discharge 1 in 1,184,943
Falling from high place 1 in 2,795,546
Drowning or submersion 1 in 1,111,742

18 Risk of dying next year: Medical Conditions
Complications by medical and surgical care 1 in 101,281
Various medicaments and biologics 1 in 41,828
Anti-epileptic, sedative-hypnotic, etc 1 in 281,193
Overexertion, travel and privation 1 in 2,249,541

19 Likelihood of Mother Dying During Childbearing
In Developed Regions of World 1 death per 5000 live births
In Europe 1 death per 4167 live births
In Latin America and Caribbean 1 death per 526 live births
In Asia 1 death per 303 live births
In Africa 1 death per 120 live births

20 Lifetime Risk of Death in Childbearing
(includes risk per pregnancy and likely number of pregnancies.)
In North America 1 in 3750
In Europe 1 in 1895
Lain America & Caribbean 1 in 150
In Asia 1 in 105
In Africa 1 in 15

21 Unintentional Injury Deaths in Infants <1 year of age
Mechanical suffocation 1 in 18,970 live births
Motor vehicle (traffic) 1 in 22,075 live births
Fire and Flames 1 in 35,211 live births
Drowning 1 in 46,948 live births
Inhalation of non-food object 1 in 57,142 live births

22 Annual Risk of Death at Work
All workers 1 in 28,571
Agricultural workers 1 in 3,425
Mining 1 in 3,534
Professional & Business services 1 in 34,483
Financial activities 1 in 142,858

23 Annual Risk of Death at Home
All people, all risks 1 in 7,875
Death from Falls 1 in 23,162
Death from Poisoning 1 in 30,288
Death from Fires 1 in 87,500

24 Annual Risk of Death from Choking
Overall rate of Death 1 in 70,000
Risk for Teenager 13-20 years 1 in 1,000,000
Risk for Senior aged 53-63 years 1 in 100,000
Risk for Aged Person 75-84 years 1 in 10,000
Risk for Person 90-94 years 1 in 2,000

In general, we are all “at home with” many of the risks of likelihoods in the range 1 in 10,000 to 1 in 10 million.  When you examine the broad band of likelihoods for potentially fatal risks, it suggests that some high profile worries are of such low probabilities that logically society might do better to devote its resources to other more routine risks that are harming or even killing many more people in our society.

Similarly, events that have a high likelihood, and that are becoming more severe in term of damages should be revisited in terms of resources devoted to risk identification, risk prevention, risk remediation and in the case of flooding risks, emergency response.

Flood Safety Guidelines for Depth and Velocity

Design guidelines used by flood plain managers, water resource engineers and planners consider both the depth and velocity of water to assess a person's stability in the water.  These criteria are used to establish flood risk maps that may preclude development or, if not possible, require special design considerations to reduce risk to occupants (e.g., flood proofing).

Velocities and depths in the shallow flood "fringe", as it's called in Ontario two-zone floodplains, may support conditional development.  In other cases a Special Policy Area may be designated to support modest redevelopment in in the floodplain, but only in exceptional cases.

The Calgary Bow River flood risk map shows the risk areas on a plan view for the 100 year flood (an event that has a 1% chance of occurring in any year). The yellow areas of shallow slow-moving water are similar to the flood 'fringe' in terms of reduced risk.  Certainly buildings and property are still at risk of flood related damage in fringe areas.

Some provincial guidelines are presented below.

General rules of thumb are:

 “3 x 3 rule” - developed in the U.S. based on 3 ft depth and 3 ft/s velocity values. The rule suggests that people would be at risk if the product (multiple) of the velocity and the depth exceeded 0.8 sq.m/s (9 sq.ft./s).  So slow moving water at 0.1 m/s and 0.8 m deep has a product of 0.8 sq.m/s and would the just stable for an adult, and so would 0.2 m/s and 0.4 m deep.

Some detailed discussion from Ontario provincial guidelines follow:

(1) Flooding as a Threat to Life

Hazard to life is linked to the frequency of flooding, and to depth of flood waters and the velocity of flow in the floodplain. Depth increases buoyancy and velocity increases instability, so that each of depth and velocity should be studied independently or as a combined function.

(a) Depth

Any person in the midst of a flooded area will be acted upon by a buoyant force equal to the weight of water displaced by that person. The volume of displaced water and this force increases with depth until neutral equilibrium is reached and the person begins to float.

Average adults and teenage children remain stable when standing in flood depths up to about 1.37 m (4.5 ft.). The average school child 6 - 10 years old would float at about 1.1 m (3.5 ft.), although smaller, younger children in this range would float at a depth of about 0.98 m (3.2 ft.).

Hence, in terms of depth and individuals who could be present in the floodplain during a flood:
• depths in excess of about 0.98 m (3.2 ft.) would be sufficient to float young school children;
• a depth of about 1.37 m (4.5 ft.) is the threshold of stabilityfor teenage children and most adults.

(b) Velocity

Moving water in the floodplain exerts a lateral force resulting from momentum thrust of the flood flow. This force acts to displace objects in a downstream direction. The shear force of friction of a person on the wet surface of the floodplain resists this force. However, even relatively low velocities of flow in the floodplain can pose possible flood hazards.

The force exerted by various flow velocities can be developed for different age and size groups, but because its effect is tied to depth, a better appreciation of velocity effects can be gained by looking at both depth and velocity in combination.

(c) Combination of Depth and Velocity

As a guide for personnel involved in stream flow/depth monitoring, the simple “3 x 3 rule” was developed in the U.S. based on 3 ft depth and 3 ft/s velocity values. The rule suggests that people would be at risk if the product (multiple) of the velocity and the depth exceeded 0.8 m2/s (9 ft.2/s).

The Water Survey of Canada has the same rule of thumb and its Hydrometric Field Manual (1981) states, “a general rule of thumb which has been used in the past is arrived at through the product of the depth and velocity. Generally speaking, if the bed is firm and provides good footing, the product of these two factors should be slightly less than 1 m2/s, or roughly 9 ft.2/s”.

It should be noted that this rule of thumb applies to trained professionals whose regular work accustoms them to the dynamic forces of river flows, buoyant forces from partial submergence and recognition of potential hazards, e.g. rocks, depressions, etc. They also enter the stream with equipment which will assist them in maintaining stability, e.g. tag line, wading rod, strap-on cleats for greater stability.

It is considered highly unlikely that such equipment would be available to most occupants of floodproofed buildings in the flood plain. It seems equally unlikely that these occupants would have the same level of
experience as water survey staff in dealing with high depths, current speeds, unsteady footing, or cold weather/water conditions.

As a result, it is likely that the simple rule of 3 x 3 product (1 m2/s or 9 ft. 2/s) represents an upper limit for adult male occupants in the flood plain and that it would be reasonable to consider something lower as being
more representative of a safe upper limit for most flood plain occupants.

As noted earlier, any person on foot during a flood may be subject to a number of forces in the floodplain. Excluding impact by ice and/or other debris, these forces include:

• an upward buoyant force, equal to the weight of the fluid displaced;
• a lateral force exerted by the moving water (linear momentum);
• unbalanced hydrostatic forces.

Resisting these forces are:
• the shear force of friction acting through the weight of the person standing on a wet surface in the floodplain.

Figure 6-1 provides a graphical representation of depth and velocity hazards in the flood plain to show the limits of stability. Unit weights of 976, 1464 and 1952 kg/m2 (200,300 and 400 lb/ft.2) are used. Adults of average size would fall into the range between 976 -1952 kg/m2 (200 - 400 lb/ft.2) but young children would more appropriately fall into a range of 732 - 1464 kg/m2 (150 - 300 lb/ft.2). Only 7% of Ontario’s population is within the 6 - 10 year age range, i.e. young children (Statistics Canada, 1981).

What Are The Odds? What Is Insured?

Compare the risk of dying from common causes to more rare events including natural disasters and flooding. All figures below are for U.S. residents.  In each case these are "Lifetime Odds" of dying:

Heart Disease 1-in-5
Cancer 1-in-7
Stroke 1-in-23
Accidental Injury 1-in-36
Motor Vehicle Accident* 1-in-100
Intentional Self-harm (suicide) 1-in-121
Falling Down 1-in-246
Assault by Firearm 1-in-325
Fire or Smoke 1-in-1,116
Natural Forces (heat, cold, storms, quakes, etc.) 1-in-3,357
Electrocution* 1-in-5,000
Drowning 1-in-8,942
Air Travel Accident*1-in-20,000
Flood* (included also in Natural Forces above)1-in-30,000
Legal Execution 1-in-58,618
100-sided die 
Tornado* (included also in Natural Forces above)1-in-60,000
Lightning Strike (included also in Natural Forces above)1-in-83,930
Snake, Bee or other Venomous Bite or Sting*1-in-100,000
Earthquake (included also in Natural Forces above)1-in-131,890
Dog Attack 1-in-147,717
Asteroid Impact* 1-in-200,000**
Tsunami* 1-in-500,000
Fireworks Discharge 1-in-615,488
** Perhaps 1-in-500,000

SOURCES: National Center for Health Statistics, CDC; American Cancer Society; National Safety Council; International Federation of Red Cross and Red Crescent Societies; World Health Organization; USGS; Clark Chapman, SwRI; David Morrison, NASA; Michael Paine, Planetary Society Australian Volunteers

It makes sense that the most common risks could be insured.  The top 5 health-related events are covered by life insurance or AD&D insurance.  Self harm and legal execution could not be covered by insurance. Of the remaining events, many are covered by insurance in Canada except flooding.  While flooding ranks relatively low down on the list of events in terms of casualties,  it is clear that the risk of a non-lethal event and property damage is much higher.  For example, the following table identifies the number of calls received from the public (in the City of Toronto) that reported basement flooding as a result of sewer back-up and/or overland flooding.

District  Total Calls
East        56
North     991
South     607
West      3105
Total      4759

It would be worthwhile identifying how many of these are caused by overland flooding and to what extent the overland flooding contributed to sewage back-up.

Urban Flood Risk Evaluation

Overland flood risks in urban areas are related to a couple of simple factors: i) how much water is running off and ii) does it have somewhere safe to go (i.e., not into your home or business).

Both of these factors can be determined qualitatively by i) identifying the drainage area that contributes runoff toward the overland flow path (or the major drainage system as it is called), and ii) evaluating whether the flow path is free-flowing, or alternatively whether it is obstructed by barriers to flow and therefore subject to ponding or 'back-up' along the surface.
This 3D image shows an elevation model along the north side of the Avon River in Stratford, Ontario.  Thicker blue lines show flow paths with large runoff areas (more runoff and higher risks), while narrow lines show flow paths from smaller areas (less runoff and lower risk).  These lines are generated using Geographic Information System (GIS) functions considering the underlying ground elevation model.  The lines do not show the width of flow, just the centreline of the flow path.

Areas with no continuous slope toward the river are show as blue 'ponds'.  These areas reflect sags in the ground surface and indicate how deep water must pond before surface flow is free flowing again.  The GIS terminology for these depressions is 'sinks'.  Like the flow paths, these sinks only show potential flood risks - e.g., if the storm sewer system below the surface is oversized, it may prevent ponding in the risk area.

Notwithstanding the limitations of qualitative risk assessments for overland flooding, there is no doubt that large drainage areas and limited grading toward a safe outlet are important factors in urban flooding risk. The proposed class action lawsuit area in Stratford following the July 28, 2002 flood was generally bounded to the north by the Avon River and Lake Victoria, to the east by Romeo St., to the south by Lorne Ave. and to the west roughly by John St.  This higher risk area is characterized by very large external drainage areas and limited overland slopes.

Specifically in Stratford, a large 1350 ha external area is partially intercepted on Lorne Avenue and then diverted, westward away from the high risk class action area.  During large storms however the diversion sewer could be overwhelmed, sending flood water northward.  The Dufferin/Brydges Trunk is characterized by very mild slopes and limited overland flow relief - it was reported that streets like Brydges, Inverness, Norfolk and Whitelock were among the most impacted in 2002.

Similarly, Romeo Storm Trunk Sewer (aptly named in Stratford) used to be Romeo Creek ages ago and has been enclosed, posing further overland flow limitations in the south side area.  The trunk sewer is said to run directly under the Avon Theatre, potentially offering special effects during performance of Shakespeare's The Tempest.

Flooding Frequency Increasing - Health Impacts Emerging

Flood events are the most frequently occurring natural disasters worldwide, and the costs and impacts are steadily rising.  In Canada, flood damage claims now exceed exceed that of other events and this affects regions across the country. Some stats:

  • Most home insurance claims in Canada deal with water damage, not fire.
  • Floods occur five times as often as wildfires, the second most frequent natural hazard in Canada.
  • Between 1900 and 2005 there were 241 flood disasters in Canada

While there is inherent uncertainty in the underlying meteorologic and hydrologic predictions, climate change impacts may increase risks in the future. While these

economic impacts of flooding are clear, a limited number of short term epidemiological studies have been conducted to assess the health impacts of flooding.

The European Commission notes that data on flood events shows "... the greatest "burden of mortality" is from drowning, heart attacks, hypothermia, trauma and vehicle-related accidents. The speed of onset of floodwaters is a determining factor in the number of immediate flood-related deaths."
Underpass Flooding - Toronto July 8, 2013

Flash flooding can occur in urbanized areas whose smaller catchments respond quickly to short term rainfall bursts.  Generally, this does not result in drowning risk as overland flow along streets is shallow.  Nonetheless, runoff can accumulate in depressions and behind embankments that are a barrier to flow, resulting in high localized ponding that can pose a risk.  It is not uncommon to have underpasses flooded in this manner in urban areas.

In contrast to flash urban flooding, river flooding in valley systems that drain large watersheds can be slower to respond and and may be more sensitive to longer term rainfall volumes than short term rainfall intensities.

The European Commission lists the following regarding other adverse health effects related to flooding:
  • Trauma deaths, mainly by drowning. Drowning is the leading cause of death in case of flash floods and coastal floods. Fatal injuries can occur during evacuation or during cleanup activities.
  • Flood-related injuries, such as contusions, cuts and sprains have been reported in several studies, as have burns, electrocutions, snake bites and wound infections. However, the number of serious injuries observed after violent flooding events generally turns out to be much lower than initial estimates predict.
  • Enteric infections due to the disruption of sewage disposal and safe drinking water infrastructure.
  • Increases in mental health problems such as anxiety, depression, sleeplessness, and post-traumatic stress disorder among flood victims. The risk estimates for physical illness in adults declined after adjustment for psychological distress, while psychological distress remained strongly associated with flooding after adjustment for physical illnesses.
  • Vectorborne disease, such as malaria, dengue and dengue hemorrhagic fever, yellow fever, West Nile fever and rodent-borne disease, such as leptospirosis. There is some evidence that diarrhoeal disease increases after flooding, particularly in developing countries but also in Europe. Standing water caused by heavy rainfall or overflow of rivers can act as breeding sites for mosquitoes, and therefore increase potential exposure to infections such as dengue, malaria and West Nile fever among people affected by the disaster and among emergency workers. West Nile fever has emerged in Europe after heavy rains and flooding, with outbreaks in Romania in 1996-97, the Czech Republic in 1997 and Italy in 1998.
  • There is also an increased risk of infection from diseases contracted through direct contact with polluted waters, such as wound infections, dermatitis, conjunctivitis, and ear, nose and throat infections.
  • Contamination by toxic chemicals during floods is theoretically possible but no verifiable correlation has been observed or measured so far.
  • Other negative health outcomes, for example related to the disruption of healthcare services and population displacement."

Flood Insurance in Canada

Canadian Underwriter highlights two flooding events that are ranked "the most expensive natural catastrophes ever in Canada, prompting insured loss estimates well in excess of $2.5 billion".  These events are the southern Alberta flooding and flash flooding in and around Toronto in 2013.  Senior executives of reinsurance companies in Canada were polled on what they see ahead for 2014.

On the topic of flooding. Steve Smith President & Chief Executive Officer Farm Mutual Reinsurance Plan noted:  “Recognizing that Canada is the only G8 country that does not currently provide some form of flood insurance response, it would appear that the Canadian insurance industry is on the cusp of developing and providing an overland flood cover. If the industry is going to pay the claims anyway, let's develop a workable flood model, clean up the wordings, provide the cover and charge for it.”

By overland flooding he means flooding from rivers or overland drainage systems whereby water enters a property through windows, doors and other openings - not basement flooding from a floor drain, which can have flood insurance, sometimes as an option on a homeowner policy.

It is relatively strait-forward to identify if a property was affected by "riverine" flooding (that is the uninsured kind of flooding).  This map shows flood vulnerable areas in the Toronto area.  There are numerous locations along major watercourses in Mississauga, Toronto, Markham, Pickering and Ajax.

As an example, lands surrounding Cookville Creek in Mississauga are flood-vulnerable.  The flood risk areas are already defined on floodplain maps - these are estimated based engineering simulations of extreme storm runoff and the resulting flow and flood depth through the valley systems.

A 2012 study (Cooksville Creek Flood Evaluation Master Plan EA)  identified over 300 properties vulnerable to flooding during the regulatory storm (Hurricane Hazel).

This includes Rhonda Valley properties along the east bank of Cookville Creek shown on the left.  The top image is the Google Streetview in sunny weather while the bottom image shows the floodplain extending up onto neighbouring streets on July 8, 2013.

Properties in a floodplain may not be eligible for insurance coverage today because overland flood coverage is not available.  It is possible, however, that overland flooding in one neighbourhood contributes to sewer backups in another downstream that does have coverage.  This can occur when overland flood water enters homes through windows or walkouts and then enters the wastewater system through basement floor drains. These types of inflows can quickly overwhelm the downstream sanitary sewer causing a mix of diluted sewage and flood water to back up in neighbouring basements.

It is more challenging to identify the overland flood risk beyond valleys where floodplain maps are available. As the following image will show, during the July 8, 2013 extreme rainfall in the Toronto area, flooding was not concentrated along valleys - it was reported on "table land" where runoff overwhelmed the major drainage system (roadways and ditches) and sewers.

Similarly, on August 19, 2005, and on May 20, 2000, flooding in Toronto was also widespread beyond the valley systems (see below).  While estimated floodlines are available for some urban areas beyond the valleys, typically a detailed engineering study is required to identify overland flow risks,  and these are often evaluated jointly with the sewer system capacity.  The Toronto map identifies several of these Environmental Assessment ("EA") project areas.

If the Canadian insurance industry is truly on the cusp of developing and providing an overland flood coverage it will have to consider risk areas.  Some risks are already defined through valley floodplain mapping (riverine flooding) while other urban flooding risks on "table land" are not.  Tools are available to estimate the urban flooding risk by identifying low-lying areas and those with large drainage areas without a defined major flow route.  The analysis can be done quantitatively using a good elevation model and GIS-based hydrology tools and can feed into more quantitative assessments of risk.