The conflicting nature and tradeoffs of planning: The case of the flooded trail

Walking the streets–or Northampton’s case, its trails–is when a person learns about the environment. We took a pre-lunch walk with Joe along the Smith College Trail, which runs right beside the Mill River.

We were also left with a few lessons on the reality of what planning work entails because of an eroded part of the trail. This is a micro-level example of something that planners have to deal with, but it’s a fascinating case for me all the same, because of the public-private interplay on land. It was also a good case for my buddy Fai, who is an environmental engineer working on phytoremediation. Let’s take a closer look.

 

About the trail

The red line shows the entirety of the Smith College trail. (Take note of the terrain elevations.)

This portion of the trail is where the eroded area is located, and where the river protective wall stops.

The trail is right beside the Mill River, which can flow harshly at times, inundating or eroding the original walking trail.

 

Here are a few photos of what the trail looks like:

The eroded part of the trail contains water (and tiny fish!), fallen branches, stones, making it a rough way for joggers, walkers, and dogs to pass through.

 

So as human nature goes, people created another trail, which is on private land.

 

See the wall on the right? The continuity of its protection stops when it comes to this place, and may put more pressure on the areas without the wall.

 

So what are the premises and issues?

• First is that people who regularly pass through the trail will require a convenient trail on which to walk or jog on.
• The original eroded public trail will require solutions such as infill, which will require heavy equipment to enter the trail, and the infill will have to be strong enough to withstand the inevitable heavy water pressure and course from the river.
• Infill and bringing heavy equipment into the area are not ideal because of their probable impacts on the trail.
• The new elevated private trail belongs to a family that created a mound to protect a part of their lands from the river. The artificial creation of a mound may be effective but may be against the principle of sustainability’s keeping landscapes natural.

 

Other factors

• The river wall does not go all the way, protecting the entire stretch. The proximity of the wall’s end to the eroded trail is an area that can flood badly if the river swells.
• River swelling is inevitable during specific incidents and seasons, especially after winter.

 

What are the City Planning Office options?

Planning solutions show conflicts of sustainability principles, prioritisation of the case among many other city works, and the dynamic between private and public use. Some options would include:

• Maintain the original public trail and infill the eroded area (explore a sand-stone base for drainage, then layers of infill). Implications would include the following: (Pros) City continues to operate on public land, and people get their trail. (Cons) Prone to future damage because of the inevitable river current and swelling. The infill would require huge stones, which will require bringing equipment into the river area.
• Use the new elevated private trail, and negotiate with the owner on what to do about the trail. Implications include: (Pros) The newer, safer trail is existing and elevated from the erosion-prone area. (Cons)  The City Planning Office would have to manage negotiations with the owner, who wants the city to manage the elevated area if they buy the land, which means too much work for such a small area; the privately created mound is against sustainability principles.
• Use other natural solutions, such as vegetation for eroded areas. Implications include meticulously designing the eroded area because planting trees will cover part of the trail. Timely planting and landscape design are critical to making the effort work. Trees used to prevent erosion and slope failure and stabilize the soil include willow and silky dogwood (specific to this location). Another way to increase herbaceous ground cover is to use wetland seed mix and cover the area.

Source: fs.usda.gov

So there hasn’t been a resolution on this case yet now, but there’s the planning lesson on looking into a variety of options, tradeoffs of pros and cons.

I also go back to something I learned in my first subject in planning: Water will always take its natural course, so using natural courses to deal with it will always be preferable to using artificial mitigation measures.