Sometimes it happens in person and other times by phone or email, but every week I hear from a variety of folks who wish to address something covered in this column.  

So, I’d like to begin 2025 by extending my heartfelt gratitude to those who have taken the time out of their busy days to engage with this writer.

The information, opinions and observations provided by you not only convey valuable insights that otherwise may have been overlooked, but also have guided the content — and often the quality — of the column while ensuring the column continues speaking to the issues and concerns of NOTL citizens.

Thank you.

The final Arch-i-text column of 2024 (“All about green infrastructure,” Dec. 19) was no exception and I received a number of communiques — a few of which I’d like to expand upon this week.

One reader pointed out to me that a document entitled “Climate Change Adaptation Plan” had been authored and published by the town of Niagara-on-the-Lake during the tenure of the previous council in March 2022.

The result of a collaboration between the town’s environmental advisory committee, Brock University, municipal staff and various community stakeholders, this 48-page document (which can be found at NOTL.com) is a solid piece of work providing background, rationale and broad objectives for developing actual action and management plans. 

These plans would translate the six goals of the Climate Change Adaption Plan – Integrate Climate Change into Plans, Policies, By-Laws and Standards; Urban Forest Resiliency; Reduce Flooding Risks; Incorporate Climate Change in Design and Construction; Minimize Health and Safety Risks to Community Members; and, Support Public Awareness and Education – into real and concrete processes and policies for town staff to follow and enforce.

Interestingly, many of the identified objectives for action/management plans call for the broad institution of green infrastructure elements.

“Appendix E – Implementation Schedule,” beginning on page 36 of the published plan, details 19 action items related to the development of those “real and concrete processes” with associated timelines commencing in 2022 and, for many, completion before 2024.

To my knowledge, none of these action items have been completed and few, if any, have even been commenced.

Indeed, the reader who bought this document forward indicated she was “unaware of any action that has taken place on the plan during the past two years.”

It appears, based on the absence of any evidence of work on these action items, this is another “inconvenient truth” the lord mayor and certain members of the current council have shelved to languish in the dark as incompatible with their “development of GTA” suburbia agenda.

Moving on, another reader observed: “The Miyawaki mini forest sounds fascinating. Can you elaborate on what it is?”

Developed by Japanese botanist Akira Miyawaki about 40 years ago, the basic concept involves utilizing native species in dense plantings which results in high levels of competition forcing growth upwards rather than outwards.

A Miyawaki mini forest is ideal for defined and/or space-constrained areas and has proven to be successful in footprints as small as three metres by three metres (roughly 10 feet by 10 feet) and, importantly, can achieve mature heights with fully realized ecosystems in about 20 years.

It is comprised of four distinct (but inter-related in the functioning ecosystem) parts: The canopy trees such as oak, tulip, hickory, white pine; sub-canopy trees like black cherry and yellow birch; understorey trees like dogwood and redbud; and shrub/ground covers which might include maple leaved viburnum.

Net-net, a fast-growing native ecosystem that rapidly augments the tree canopy while delivering a multitude of ecological benefits that can be planted in urban backyards, municipal parks and many other locations.

And the really cool practical thing?

After the first three or four years, it is virtual maintenance-free. Something which is a boon to private property owners but, on a municipal level, could have a really significant impact vis-à-vis reducing operating costs for the parks department.

There are many articles and studies available online: Google “Miyawaki forest.”

Another reader, and regular communicant, suggested that green infrastructure would “require considerable extra planning in the town,” felt that “green infrastructure adjacent to orchards and vineyards is not a good thing” and went on to observe that, in his opinion, the town has not been adequately maintaining the drainage ditch infrastructure to properly manage stormwater runoff.

Now, those folks who are urban dwellers may not be aware that NOTL has an extensive network of open ditches designed to manage both surface and subsurface runoff of stormwater deposited during weather events. This is a crucial component of the town’s flood mitigation strategy.

According to the Ontario Federation of Agriculture, “Under the Drainage Act, municipalities have a statutory obligation to repair and maintain municipal drains, in accordance with their original design specifications. These design specifications are found in the engineer’s report, which was adopted by municipal bylaw, giving the drain its legal status.”

Further, this repair and maintenance must be performed in accordance with published “Standard Compliance Requirements.”

From a technical paper published by Fisheries and Oceans Canada entitled “Ontario Municipal Drain Maintenance and Repair,” we understand that, “Drains require maintenance and repair to ensure adequate movement of water.”

And the most common associated activities “involve bank repair or stabilization, brushing of vegetation on top of banks and along bank slopes, and removal of accumulated sediment and vegetation in a drain.” 

In other words, because these drainage ditches have been traditionally designed to accept uncontrolled stormwater runoff, it is necessary to remove vegetation that would inhibit water flow.

Unfortunately, uncontrolled water runoff also carries with it soil particles that result in the sedimentation of the ditches and can (and does) result in bank erosion.

Further, this nutrient-rich (phosphorus and nitrogen) sedimentation from agricultural fields in the open ditches encourages the growth of vegetation — particularly of invasive plant species — in the bottom of these ditches that impede water flow.

In an effort to combat these issues, many jurisdictions around the world are recommending or requiring the establishment of properly designed riparian buffer zones — either wooded or grass or a combination of both — to reduce sedimentation and control erosion while filtering out phosphorus and nitrogen (amongst other contaminants).

A publication from North Carolina State University, published in 2023 and authored by Deanna L. Osmond, cites studies that “measured 80 to 95 per cent nitrate removed from the groundwater” and has been observed to occur “within the first 15 feet of the forested riparian buffer.”

The author also illustrated studies that found a 14-foot riparian buffer reduced sedimentation by 70 per cent, while a wide 91-foot grass/forest riparian buffer reduced sedimentation by 97.4 per cent, nitrogen by 80.1 per cent and phosphorus by 77.2 per cent.

Other studies have shown that as a balanced ecology is achieved in forested riparian buffers, there was a measurable decrease in agricultural “pests” — both insect and avian.

Perhaps Ontario should consider riparian buffers?

It seems to be the trend elsewhere in the world.

Hmmm … I wonder how a Miyawaki forest would do as a riparian buffer.

And here’s a fun fact: There are species of native dogwoods which are commonly used to stabilize stream banks and actually help control invasive species such as phragmites.

Brian Marshall is a NOTL realtor, author and expert consultant on architectural design, restoration and heritage.