Flash flood hits Alewife path hard

Parts of the Alewife Greenway are no longer accessible to people with disabilities following a violent storm that damaged the path’s stone-dust walking surface.

Where the Alwife path slopes down north of Mass. Ave., storm waters exposed underlying gravel fill.

Storm water exposed underlying gravel fill where the Alewife path slopes down north of Mass. Ave.

Extreme weather that temporarily shut part of Mass. Ave. in East Arlington and brought a rare tornado to Revere also took a toll on the Greenway.

The July 28 storm tore a huge rent in the surface of the path where it slopes from the north side of Mass. Ave.. The deep flaw exposed the underlying gravel fill, which was washed downstream along with a good deal of stone dust.

Once detached from the path surface and rinsed of its binders, the stone dust becomes lose sand that accumulates in a thick layer on the low points of the path. It is this soft runoff material, not the eroded bumps and canyons, that presents the greatest obstacle to people using wheelchairs and walkers.

The soft sand is thick enough to trap and hinder the wheels of chairs and walkers. Note bits of gravel, washed from the underlying fill, mixed in with the sand.

The soft sand is thick enough to trap and hinder the wheels of chairs and walkers. Note bits of gravel, washed from the underlying fill, mixed in with the sand.

The second photo shows this runoff, studded with gravel fill and scored deeply with footprints and the marks of bicycle tires.

I walked the entire Greenway on July 30. The worst patches were in the northern segment between Broadway and the Mystic River, but it was not clear that those were all created by Monday’s storm. One woman on the path that day was relying on a walker.

The flood also carved deep channels into the much-eroded, sometimes-repaired, entry to the path from Cottage Ave.

Water glints at the bottom of newly carved canyons at the Alwife entrance that is at the foot of Cottage Ave. a few hours after the storm.

Water glints at the bottom of newly carved canyons at the Alewife entrance that is at the foot of Cottage Ave. a few hours after the storm.

Cottage 30 2

Cottage Ave looking roughly east. The entrance path is no longer accessible to people with disabilities.

This effectively closes that entrance to people who rely on wheeled support, but generally the soft runoff probably poses the greatest mobility problem.

The Greenway is still wonderful, and mostly navigable, but the damage of last week just underscores the challenge of taking care of it.

Over time in any park will erode and break and need care. The Greenway fence broken by trees felled during Superstorm Sandy is still not repaired nearly 2 years later.

The flood exposed this gravel fill along the path just north of Mass. Ave. If not repaired, the substrate will continue to erode too.

The flood exposed this gravel fill along the path just north of Mass. Ave. If the surface is not repaired, the substrate will continue to erode too.

Last weekend neighbors were out picking up trash along the brook, but repairs of this scope are really beyond the reach of volunteer groups.

The usual stuff: This is a blog about Mass. Ave., mostly, and the Greenway is but a pleasant detour.

Nonetheless readers will know that I have spent some electrons here documenting the construction of the part of the Alewife path that is closest to my house on Cottage Ave., and that I’ve touched on erosion before.

Today’s post is the latest in a series of Alewife stories starting with this one from July of 2010. The previous report in the series before this one examined the state of trees and shrubs on the Greenway as of April of 2013.

Update: The state responds to the path damage in the next Alewife report.

Advertisements

No comments yet

What do you think?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: