Partial Greenway repairs await complete fix

A permanent remedy to some erosion problems on the Alewife Greenway may finally be in the works.

At Cottage Ave, the DCR left these marks and the words "Handicapped ramp 4' wide" on or before May 15.

At the Greenway’s Cottage Ave. entrance, the DCR left these marks and the words “Handicap ramp 4′ wide.” Click any photo for a close-up.

But will the Department of Conservation and Recreation make the structural changes in time to preserve recent repairs it made to the eroded path surface?

The soft stone-dust surface of the Greenway has many virtues, but is subject to erosion where not perfectly level.

The record of repairs suggests a need to mend some segments every 2 or 3 years. The most recent round of repaving took place at last spring.

One problem area is the path entrance at the end of Cottage Ave., near my house.

Cottage Ave. slants down towards the brook. When it rains the street bears fast-moving rainwater runoff from blocks away that strikes the Greenway entrance with great force.

The stone dust there and in other eroded locations was replaced during the last week of May, but runoff continues to hit the entrance during heavy and even moderate storms.

Meanwhile the DCR has been studying the problem for years. Damage from flash flooding last summer added new urgency to finding a permanent  solution.

A history of erosion

I’ve been concerned about erosion there since before the Greenway was even completed. I met with the Town Engineer about the problem in 2011. The entrance has been repaired several times, including new stone dust in 2012, part of patches to several trouble spots on the path at that time.

However, a promised design change to divert the runoff into drainage swales never materialized. After flash flooding damaged the stone dust in several locations a year ago, the DCR took up the problem again.

The department’s director of planning and recreation, Dan Driscoll, visited Cottage Ave. last August and discussed structural changes to the entryway that could divert runoff away form the stone-dust surface.

Repairs made and promised

A repair crew arrived at Cottage Ave the morning of May 27, part of what I learned was a general push to spruce up state parks in the area.

The Department also gave the Greenway its annual mowing and cleared some of the fallen tree-limbs at the end of May.

At Cottage Ave. the entrance splits into two short paths that join the Greenway north and south, forming a triangle. Both of these little branches had been repaired and rebuilt numerous times.

By this spring, the northern path was largely washed away and the southern path was also seriously eroded, with some of the underlying gravel washed to the north and onto the Greenway.

There were deep ruts in part of the entrance, and loose sand and gravel, complicating access for those with mobility issues.

The paths were scraped down several inches on may 15. View east from Cottage Ave.

The paths were scraped down several inches on May 15. View east from Cottage Ave; note “triangle.”

On May 15 the DCR cleared all that away, leaving the entrance and a segment of the Greenway excavated to a depth of several inches.

This exposed the concrete anchor for the metal bollard that you can see in the photo at right.

Workers left this sign across the entrance on May 28.

Workers left this sign across the entrance on May 28.

Repairs were made the week of May 27.

At about the same time, the DCR also repaired other eroded segments on the Greenway.

A badly rutted section near the northern terminus of the path, by Arizona Terrace, got new stone dust. Another segment just south of Centennial Park near Mass. Ave. was similarly refreshed.

The sloping entryway near Centennial Park was paved with asphalt, a concession to the limits of stone dust.

Another eroded entrance to the path near the junction of Boulevard Road and Lafayette Street was not repaired.

This entryway was also passed over during a previous round of repairs in 2012. It is in pretty rough shape.

Incomplete restoration

The resurfacing apparently did not include replacing the coarse gravel layer on which the Greenway was originally constructed.

Stone dust sits on coarse gravel stabilizer. This unusual cross-section was briefly available during construction in 2010.

Stone dust sits on coarse gravel stabilizer. This unusual cross-section was briefly visible during construction in 2010.

The gravel layer was at least partially washed away on the southern “branch” of the Cottage Ave entrance, and was never laid down at all on the northern branch.

I may have missed something, but there was no way this gravel could have been replaced with the equipment that I saw, and within the time that work took place, in May.

A permanent fix

Ramp lettering

Handicap ramp 4′ wide

Most tantalizing of all were the marks that the DCR left on the pavement at the bottom of Cottage Ave. It would only take a few inches of elevation to direct storm water away from the path entrance and into the drainage swale a few yards to the south.

DCR Cut

Cut pavement looking west up Cottage Ave from the Greenway entrance on May 28.

In addition to “ramp 4′ wide,” the word “berm” was written along the curved line indicating the ramp’s edge.

On May 27, while the resurfacing was under way, DCR cut the pavement along what I take to be the property line (see photo). Things certainly seemed to be happening.

So it was puzzling—and anticlimactic—when DCR simply replaced the affected pavement with fresh asphalt.

Repaved cottage

Fresh pavement delineates state property on May 29. Will there be a berm and a ramp?

The old pavement there was in pretty good shape.

Predictably, the new pavement does not deflect heavy runoff from the path entrance, and the new stone dust is already showing wear marks from it.

So. This is a blog about Mass. Ave., where there is plenty going on this week. No shortage of brawny construction photos as the project closes in on the end of sidewalk reconstruction.

But at the risk of sounding jaded, that’s all starting to blur together. And readers of this blog will remember that I have been posting photos of Greenway construction near my house since mid 2010.

The drainage stuff feels like a loose end.

The Greenway posts are linked in series, and you can view the most recent of those (August 2014) or the first one (July 2010) or all at once, most-recent first.

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