I'd wonder about the elevation change between the path and the fields. There would either be a very steep incline on the trail to get behind the bleachers, or a lot of earth moving to raise the land immediately behind the bleachers.
None of that hillside is original because of the embankment that was built up at some point in the last 100 years for the Grove St. grade crossing elimination. That's why the town was so easily able to build the bleachers without getting bogged down in EIS'ing. The bleachers already shaved some of that embankment when they were constructed in order to fit that narrow gravel park maint access point underneath for cleaning up all the trash behind/beneath the bleachers. So scooping the hillside isn't going to be a big deal. Transit construction would have to by default build a short retaining wall at the ROW fence spanning the bleacher area for roadbed stabilization against erosion. The bleacher construction shaved back enough that stabilization's non-optional. That's going to involve some digging for the foundation pour at this very spot. If the retaining wall is at the ROW fence it's an easy opportunity to level it out back here and drop the elevation 5-6 feet for a 30-foot wide path + grass equivalent to the current ROW and much gentler grade back to level. on either side of the playing field.
For the rest to the east you're looking at the path deviating off current alignment behind Alta Brigham Square since that's where the subway would be portaling-out after Mill St. And everything from there to Thorndike Field obviously gets a full path restoration after subway construction.
Figure that near the Mill portal the path would be landscaped to deviate off-alignment and slope down the pre-existing retaining wall behind the Alta Brigham residential community to get level with the park. Fence separating the private property from path.
Hits the park, does its shaved-down elevation thing behind the bleachers. Then on other side of the playing field it would take a strip of the DPW back lot that's currently a giant trash heap, re-landscape that whole thing into something lush for the 50 ft. behind the maint building so the rest of the facility is buffered and invisible from the path. Then crosswalk at Grove St.
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Old rail bridge over Grove is 11.5' low-clearance...probably lower-clearance than that when first built because looks like road was further undercut at some point too. Construction would certainly raise it 3-4 feet to prevent bridge strikes from the DPW trucks which necessitates more retaining wall framing Grove. So the width for the path continuation through
here gets produced by default from the raised bridge getting new retaining walls poured.
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And now you're on the Grove-Brattle block and chewing on the possibilities there. Right now, the north end abutters on Grove St. Pl. are set back 65 ft. from the ROW with dense foliage. Brattle Dr. housing development set back 40 ft. Maybe a sound wall, but between that and the foliage the train line would be undetectable.
South-facing side on Dudley St.:
-- 3 small L-shaped barracks-style housing projects buildings, like larger versions of 63 Grove St. next to the bridge embankment, all with rear parking lots. They look well-maintained, so guessing these are keepers.
Minor angst.
-- Very sketchy looking, possibly vacant warehouse (Google shows no known tenant) set way back from the street with stupidly large parking lot in front.
No-brainer nuke/redev...not appropriate for a residential street.
-- A1 Autobody. Large rear back lot fanning out both directions behind the adjacent double-deckers with smashed-up cars stored and some sort of secondary garage in back.
No-brainer nuke/redev...not appropriate for a residential street.
-- Bike shop, set up inside a former auto repair garage behind double-deckers. This is the one with the back door that opens up onto the Minuteman. Obviously you want these guys around for the trail (I've used them myself to inflate my tires en route to Lexington). But given the makeshift nature of their digs they'd be easily relocatable to a nicer spot that isn't in an ex- chop shop behind residences. Maybe that's a place for carving out a patch of the DPW lot or moving closer to Heights.
Use care on relocation, but likely a very willing negotiating partner.
-- Another chop shop.
No-brainer nuke/redev...not appropriate for a residential street.
-- 10 residential houses, single- and double-deckers, street-facing with the rear-lot autobody businesses and bike shop out their back windows. Zero backyards, some with the rear-lot pavement running literally to the back porch.
N/A...all of them 80-100 ft. in front of the ROW and probably looking forward to the day when they get a little privacy not having gearheads working behind them all day.
-- 3 residential houses with real backyards.
Minor angst.
-- Mass Control Wholesale Heating Supplies. 3 warehouses spanning to corner of Brattle St. with lots of trucks parked in/around.
No-brainer nuke/redev...not appropriate for a residential street.
I would be hard-pressed to see any issues running surface on the Grove-Brattle block with a sound wall on the north side and trail shifted and well-buffered onto space freed up on the south side by flipping those residential-inappropriate chop shops and warehouses. If that were part of the deal and the bike shop got a superior trade-in location elsewhere on the path the residents would HAPPILY make this trade for a little privacy. And the relocated path on the rear of the chop shop properties would be 1:1 as well-buffered and lush as before.
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Brattle to Hobbs Ct. This is where there's likely to be the most trouble with residential abutters on both sides of the ROW. So if you have to go back under, inclining down before Brattle St. is the place to do it. Raise the roadway under the low-clearance rail bridge to its original level during the cut-and-cover job, replace the rail overpass with a new taller footbridge and run the trail over that moved back onto its current alignment.
1000 ft. of tunneling, or tricky negotiation on mitigation around abutters. Make this your first tunneling concession if you hit a blocker.
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Hobbs Ct.: Portal on up.
North side of ROW is the park that runs all the way to Forest St. Trail gets offset to the park-interfacing side lushly buffered from the south side, and ends up improved significantly by interfacing with the recreation areas for a change.
South side is:
-- Service lot of the Mirak Chevy dealership (yuck!...why does this residential neighborhood have so many auto repair places right out their frickin' bedroom windows?).
-- Some sort of partially-occupied factory in an old mill with a hideously large, crumbling, barely-occupied parking lot in back.
-- Lalicata Landscaping Products (mulch, gravel, etc.). Just a yard full of smelly mulch, trucks and tractors.
-- Beck St.-facing businesses: another landscaping company, a plumbing company, a woodworking company, a graphic design company in a repurposed warehouses, carpet cleaners, and some nondescript warehouse.
Nothing would need to be disrupted because you're offsetting the path closer to the park, but if maximal buffering really matters that much you can just cut down the trees behind Mirak, the freakishly large mill parking lot, and Lalicata and run the tracks propped up on a short retaining wall in full view of the gearheads and guys with tractors. And for the sake of neighborhood sanity please flip-n'-nuke all the Beck St. industrial for residential. Seriously...who in Town Hall zoned all this crap back in the day?
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Forest St. bridge is another former grade separation, and Forest-Watermill Pl. another tough one for abutter angst. If you have to portal back under do the same thing you did before: do it before the bridge, raise the undercut road back to the sidewalk level, and do a taller footbridge for the path.
1100 ft. of tunneling, or tricky negotiation on abutter mitigation.
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Watermill Pl. you're in the cut on approach to Heights. Southside abutters on Lowell St. are set back a lot. Northside on Bow St. are another landscaping company and a tool rental company re-occupying old warehouses.
Don't see a problem here. Shift tracks further north, build retaining walls. The industrial properties are so close to Heights that those 2 businesses are going to get Godfather offers to move. This would actually be a frickin' excellent place for the bike shop. Path makes a slow incline up on approach to Lowell St. at-grade and the new 'square' to be build over the triangle.
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"The Square". Air rights cover-over for the station. Path surfaces into the pedestrian plaza crossing the block. Gold's Gym gets nuked for something befitting a square-anchoring redev. Train storage yard in the lumber yard and current bus yard.
The end for Phase I. Lexington's a someday in the deep future, or a never-will-be. Either way it's out-of-sight/out-of-mind for now.
2100 ft. of 'negotiation tunneling' to keep in-pocket if you need to go to the well to get it done (and hopefully you don't and other mitigation does the trick). A minimum four-fifths of a mile at-grade that you have no solid justification for gambling away. A new Square plaza on air rights.
That doesn't sound too bad. And if it un-does some real WTF? industrial vs. residential zoning mistakes in the process, you've probably got the town's buy-in to go for it.
