The Harlow berm Phase 2A/B is slated to begin construction this summer, despite the reservations of a group of residents directly impacted by this project. Council passed our 2020 budget in December 2019, but I voted against it. One of the reasons was my disagreement over funding Phase 2A/B of this flood protection project, though my objections differ from the residents of Finlay and Link Court. In my opinion $2.2 million to protect 13 homes was not a reasonable cost to benefit ratio. Especially in comparison with Harlow Phase 1, which cost $4.8 million and protected 57 homes.
In short, I do not see a way to stop the project, nor do I see a way to modify it to meet the primary concerns of the affected residents. Council has shown no indication of changing their minds. While I don’t agree with my colleagues on this issue, building a berm to protect a neighbourhood is hardly an unreasonable position. And what is a reasonable cost to benefit ratio will always be a subjective standard. Additionally, construction plans have already been approved by Alberta Environment, making changes to the berm route difficult at this point.
Here’s an explanation of the issues at play.
Harlow berm Phase 1
The Harlow Phase 1 berm, a 750 meter dyke completed in 2015, is designed to protect the western part of the neighbourhood from a 1:200 year flood.
Harlow Phase 2A & 2B
The eastern part of Harlow is divided into Zones A, B and C. In 2015 the recommended option for Zone A was a permanent berm, with on lot, temporary measures, recommended for Zone B and C.
Upon further study it was determined that extending the berm to 7th Ave SE would be necessary to protect other municipal infrastructure (River Heights lift station). As plans evolved further it was determined that extending the berm would allow the River Heights lift station to be removed and functions consolidated with the existing Harlow lift station. This rationale was not presented to council at the time of decision in the fall of 2019, but was determined during planning. There were two options for council:
Construct a permanent flood barrier, at a cost of $800,000, to protect Phase 1 from wrap around flood water tied into the east end of Phase 1 on Harris Street.
Phase 2A/B, at a cost of $2.2 million, protects an additional 13 homes east of Harris Street with a berm.
I supported the completion of Phase 1 because I didn’t want to see the money wasted on Phase 1 if it was vulnerable to wrap around flood water. I did not support the construction of Phase 2A/B because $2.2 million to protect a small handful of homes seemed too high a cost.
Out of all flood protections measures Harlow 2A/B has the lowest cost to benefit ratio and didn’t meet my standard for a reasonable spend. Of course we’d like to protect every one of our residents from every disaster. The question for our community is always—at what cost?
Berm protection and projected reach of flood events without protection.
Neighbourhood concerns
Gillian Slade and the Medicine Hat News reported extensively on neighbourhood concerns about Phase 2A/B berms.
People buy homes beside the river because of the beautiful surroundings and usually pay a premium for this experience. 99% of the time it’s a worthwhile decision. However, floods can extract a painful penalty. So there is a natural tension between flood risk and the attraction of living near the river. The residents affected by Phase 2 have a number of concerns in how the city is balancing these two things.
Risk of flooding
The City’s flood protection strategy aims to protect properties up to a 1:200 year event. Under a 1:100 year event 10/13 residents are at risk of flooding. At at 1:200 year event 12/13 are at risk.
Some residents are satisfied with managing flood risk through temporary measures. This is one option. When to rely on temporary measures and when to build permanent protection depends on a few factors.
Temporary measures are most beneficial:
when there is a low risk of flooding
where they can be easily and quickly installed particularly in response to an unforeseen event
where required to address gaps where permanent measures exist
where it is not practical and/or feasible to construct permanent measures.
Temporary measures currently behind 45 Harris Street SW and Finlay Court SW along the proposed route for Phase 2A/B.
Conversely, permanent measures are most beneficial when used at locations where a high flood risk probability and severity of impact exist, therefore requiring a need for greater confidence in reliability. They are also beneficial in areas where constructing temporary measures in time and with the integrity to withstand a flood threat pose considerable challenges.
At the end of the day council must make a judgment call between temporary or permanent measures. Reasonable people can disagree.
As more and more permanent measures are constructed our risk is reduced. Both in the severity of flood damage and in our ability to marshall our resources to other areas. Permanent berms frees up manpower to install temporary measures in other areas. Time is always in short supply during an emergency and Medicine Hat has large areas to protect during a flood.
Analogy to the Riverside berm
Another complaint is that Riverside residents successfully blocked a permanent berm that would have blocked their views of the river. I wasn’t on council when the Riverside berm was built so can’t speak to whether or not this complaint is true.
There is, however, one important difference between the two sides of the river. The homes in Riverside, west of 1st Ave NE, along the river are unusual. Typically personal property extends only to the high water mark, however with these properties they own rights up to the water’s edge. Building a berm over private land adds complexities that are not present in Harlow. Here, there is sufficient city owned land between private property and the river to allow the berm to be contained on public land.
Environmental and First Nations artifacts
There is concern about potential habitat loss and First Nation archaeological artifacts that may be at risk from berm construction. Any development along waterways requires a greater due diligence to meet provincial and federal laws. My understanding is that all provincial and federal requirements have been met.
Berm path options
Another question is how much flexibility we have in choosing the path of the berm. Moving the berm closer to the river would allow the retention of buffer trees maintaining privacy for residents. Currently trees on public land directly abut private property. The berm would replace these trees, running alongside private property lines. The loss of trees will dramatically alter the landscape. For what it’s worth the Phase 2A/B berm won’t be as high as Phase 1, as the cross section image below indicates.
Cross section of 45 Harris Street SW and its relation to the berm.
Alberta Environment does not allow for construction of berms in the floodway. Berms built in floodways pinch rivers creating higher, more powerful waters downstream.
I have walked the woods behind Harlow and there appears plenty of room for a berm setback to keep some woods and maintain privacy for the affected residents. But looks can be deceiving. Provincial maps designate most of this area as floodway (the area in red). The floodway extends almost to the edge of the affected homes. Alberta Environment has already approved construction plans and made concessions to allow parts of the berm to be built in the floodway so that the berm can be constructed on only public lands. There’s literally no room to move it over.
Designated floodway shown in red.
It would be nice to create a buffer between the berm and private property, but it doesn’t look possible.
Alternatively, planting trees on the berm would solve the privacy issue. However, trees would compromise the integrity of the berm. This didn’t make sense to me at first. But trees, especially cottonwoods, do fall over—creating large holes in the berm when they do. Second, there is an erosion effect called pipeing. Water travels along any dead root structures eroding the berm internally and potentially catastrophically. Thus a three meter setback from the berm is recommended for any trees.
How much say should neighbourhoods have?
This is the interesting question. Should neighbourhoods have a veto for significant developments? Can neighbourhoods opt out of flood protection? How much support would need to be demonstrated—a simple majority or perhaps a higher measure of unity? How far from the project would residents' feelings matter—100 meter radius or 1 km? I like the idea of delegating more decisions to neighbourhoods and have been exploring this idea. Even at a local level people bristle at the idea of governing bodies dictating to them. What people object to is rarely our decision per se, but rather that council did not engage them in the process of that decision.
City council is well within its power to decide, but since we govern with the consent of the people it’s clear that simply voting for a council every four years isn’t enough of a say. The previous council did hold a number of open houses prior to construction of these berms, however this was over five years ago. However, despite our efforts we weren’t able to avoid this dispute with the affected residents.
Future development along the river
The proposed 2020 municipal development plan would not allow new development within a 1:200 year flood zone. This does not apply to existing neighbourhoods that fall within that line.
We know that extreme weather events are increasing. We know that fighting Mother Nature is expensive and there are no guarantees. For comparison:
The average flow rate for our river is 700 cubic meters per second (cms).
During the flood of 1995 the flow rate was 5,110 cms.
The 2005 flood peaked at 3,490 cms.
In June 2013 the flow rate was 5,040 cms.
The definition for a 1:100 year flood is 5,480 cms. 1:200 is 6,260 cms.
Prevention is the best and cheapest option. The proposed 2020 municipal development plan establishes greater setbacks for new development along our river and two creeks. City council debated whether the setback should be for a 1:100 flood or 1:200 flood, ultimately settling on the more conservative choice. This is the right choice for me. Hopefully, this policy minimizes the kinds of difficult choices we have in Harlow.
Postscript
City Hall has much more information about local flood protection if you’re interested in further reading.
Of the $33 million, $22.5 million was received from provincial and federal governments, including $1.5 million for Harlow Phase 2A/B