COMMENT OF JANUARY 30, 2017 WITH ADDENDUM
Since Connecticut is location of the most circuitous portion of the Northeast Corridor and the section of it most in need of addressing in order to achieve a direct route, and since some controversy has arisen over an appropriate plan for improvements there, this comment will discuss the commenter's suggestions for improvements in Connecticut first, and briefly address the three other improvements here proposed, in New York, Philadelphia and Baltimore, below.
Clearly the first order of business in Connecticut is getting the 3-track main line and its grade crossings off the streets of New London. The configuration - now with catenary wires - has hindered development in the central business district for a long time, and is anathema to anything being billed as modern rail transportation. Officials of the New Haven Railroad no doubt considered removal of the obstructive and extreme geometry here a high priority, but were hampered by the more limited technology of the day.
NEW LONDON AND MYSTIC SHORTCUTS
The ten and three quarter miles of the two coastline shortcuts described herein take better than three miles off the existing route. They would serve to straighten the worst of the skewed headings and circuitousness of the 19th Century shore line, except in its alignment east of New Haven where it goes north and then south for six miles, but doesn't lend itself well to abbreviation or realignment.
To view the two shortcuts (described below) in Google Earth with detailed elevations and measurements, follow this link: http://www.filedropper.com/newlondonandmysticshortcuts
NEC FUTURE 44-MILE IMPROVEMENT
With respect to efficiently shortening the coastline route the two shortcuts suggested here compare quite favorably as against the 44-mile NEC Future realignment proposal, with it's fifteen miles of dual-bore tunnels. (thirty miles of tunneling) This commenter does not advocate any significant realignment, anywhere along the 115-mile coast line, except the New London and Mystic shortcuts here described. The two shortcuts have tunnels totaling 5.36 miles as drawn, by way of a proposed passenger tunnel between New London and Groton. The steepest grade is 100' per mile, occurring twice.
The 44-mile NEC Future Improvement proposal, while providing some rather waveringly headed and tunnel-encumbered opportunities for higher speed, does so at the expense of four important and potentially important passenger stations, one of which, New London, is the busiest transit node in Southeast Connecticut. Two of these stations are historical structures of particular note. New London Union Station, drawn by initiating "Richardsonian" architect Henry Hobson Richardson, should be viewed as a point of pride and customer draw by the passenger carrier, and by their planners who determine its fate, as should the station at Westerly.
It is a singular puzzlement: that a passenger carrier interested in passenger revenue has here determined that in order to provide through-passengers the advantage of a few extra minutes, it must sacrifice its own remunerative potential for developing service at these stations - hard by two apparently permanent and growing casino resorts, one of which has an existing direct-to-the-door rail connection - by building an extremely expensive four-station bypass, that is anything but direct. Clearly the best use for this 44-mile improvement, insofar as the interests of the passenger carrier are concerned, is as a freight bypass.
NEW LONDON SHORTCUT
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By way of it's subaqueous passenger tunnel, the five and three quarter miles of the New London Shortcut takes one and three quarter miles off the existing route. Absent the complementary freight tunnel, connection of lines to the north is possible by way of the north leg of a proposed wye configuration in Groton as shown. (A broader curve is possible given more acquisition.) The two extreme mainline curves in reverse alignment that now traverse the heart of the New London CBD (probably built as an afterthought to connect the two original lines comprising the modern shore line route) would be eliminated, paving the way for relief from the stunted development, and the obstructed access to maritime connections there which are closely tied to passenger rail operations.
This commenter prefers Deep to Circuitous - not counting linear augmentation due to the grade, which in this case would not be much at 1.42% - so the shorter route is achieved at the expense of having the north end of the New London Station about 20' deeper than it might otherwise be: -104' at top of rail, or about 112' below the curb.
A breezeway, enclosed in winter, giving off the listed station building at center and running past a planted courtyard with the curved ticket office window at center, would lead to a skylit pavilion envisioned as being octagonal and located over one of the shafts built to sink the TBMs, containing a few large elevators. The station expansion is seen as being of painted or unpainted somewhat decorative wood (for contrast) with plenty of glass and possibly some decorative metal; and having a peaked, segmented roof with overhang above its pavilion offset by a subtending clerestory to help accomodate superstructure of the elevators, which would be reached at center on a somewhat lower level accessed by two broadly curving stairs and a single, preferably open, lift - providing plenty of geometric interest in the annexed-waiting-room/covered-ferry-access structure with surrounding outside benches facing the harbor.
Beneath, a three-track, two-platform station of 2100' could be achieved by launching two TBMs past each other in opposite directions. Since the location does not lend itself readily to double-bore tunneling, the proposed grades are geared to a single tunnel with a minimum inside diameter of 32.5'. They are based on U.S. topography and bathymetry maps, and the satellite elevations feature of Google Earth, which is discussed in detail in the presentation on the "Connecticut Shortcut" found below.
Significant realignment of grades along the existing line in the area of Groton would be necessary, with one point near the tunnel entrance being 73' below its current elevation. On completion of the tunnel, a line extending from its east portal would be routed onto the existing line going east, with a temporary bypass already in place to route traffic around the re-graded segment lying east of the point where the tunnel line enters. The section from here to the Thames River Bridge would then be closed and re-graded. The minimal wye configuration is dependent on ground conditions being such that the deep cut at the tunnel portal can be isolated from seeping groundwater. If not, the tunnel would continue on a tangent from the east portal as shown to a point of intersection with a line extending north on a tangent from the START GRADE push pin marker located on the existing line. A purple push pin indicates the point of proposed portal. An alternate connection from the tunnel to the Thames River Bridge and lines running north would need to be achieved by a cut-and-cover operation extending along the north leg of the wye as shown, and would require temporary isolation from groundwater in any case. The lengthy hairpin alignment running through the tunnel and along the north leg works nicely to make the grade from the passenger station to the Thames River Bridge.
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The five miles of the Mystic Shortcut takes 1.29 miles off the existing route and provides a needed reconfiguration at Mystic, allowing a more direct, less intrusive alignment, without the grade crossing(s. - Some crossings have been eliminated completely by removing the road.) The proposed alignment diverges from the existing line in Groton - just south of the "START GRADE" push pin marker (upper left) - and would cross the Poquonock River about 80' south of the current bridge which would be removed. The grading scheme of the Mystic Shortcut as shown is dependent on unknown ground conditions in the area of Beebe Pond Park (green boundary, center) which are assumed to be suitable for isolating the line as it emerges from the tunnel to the east in a 40' cut, then proceeds past the pond within the cut as close as 150' away and at a level at all times lower than the elevation of the water in the pond.
The Mystic station is overdue for an upgrade including a low-slung Chinese Wall viaduct, with appropriate stone cladding as envisioned. (Connecticut Sandstone/Brownstone suggests itself to this not-from-Connecticut commenter, and plans for a uniform "look" should be agreed upon and extended to rail planning affecting a suitable geographical area.) A new or, if insisted upon, new-and-transported station would be required. The upgrade would incorporate facility for trains passing at speed, and would get the rail-induced encumbrances to commerce and development - and the grade crossing - off the map.
There is no reason, as seen by this commenter, why the first elevation marker west of Mystic as shown (10') could not have a lower reading, since the existing tracks are probably a bit lower - about 9' - and a still lower elevation at this point would enable a somewhat less intrusive configuration of the quick dip directly west of the marker, which is one of the most intrusive places in the two shoreline proposals discussed here - not that more than one house, if that, would need to be removed. Whether historic structures are affected is not known. Efforts at redirecting the route to get more cover for the tunnel in the area west of Mystic by heading in directions other than the intuitive east-west alignment seen in the picture have all resulted in increased intrusiveness, as well as length. Use of currently unconventional steal rings might help in getting a minimal tunnel section.
All tunnels of the two shoreline proposals are envisioned as being single-bore tunnels of minimum 32.5' inside diameter, except the 1.75-mile freight tunnel, which should be wide enough to allow two double-stack trains to pass, and would entail a dip and vertical curve within the tunnel since cover is lower at certain points where it passes through New London than that above the passenger tunnel, the tunnel itself being higher. Double-stack freight would traverse a single center track passing through the passenger tunnels.
The inability or unwillingness of the railroads to act has left Stonington no choice about living with the heavily-scheduled high speed grade crossings there, or in one case, building a large and hurriedly-improvised-looking bridge with awkward interfaces that casts a potential station area and large swath around it into a long shadow, hindering development and public uses. A modern reconfiguration would have the tracks elevated on a low Chinese Wall viaduct as suggested for the Mystic Shortcut. This would allow the addition of one or two tracks to enable a local stop or skip-a-stop service, and provision for passing at speed. Additional tracks should not be considered without raising the elevation of the right-of-way. Possibilities for desirable station and rail bridge configurations abound.
PLANNING TRIPS AND TRANSPORTATION
If you draw a straight line from the Bronx to Providence it runs along the north coast of Long Island Sound through the densely conurbated cities of New Rochelle, Greenwich, Stamford, Norwalk, Bridgeport and finally, New Haven. There, where the shoreline turns east, the line strikes out across Connecticut headed straight for Providence - capital of the second-densest-populated state in the country.
This should give us a hint about how to develop the NEC.
NEW HAVEN TOPOGRAPHY
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Luckily, our planet's maker has conveniently provided a topographical solution for getting out of New Haven by rail on a direct line to Providence that is twenty-seven miles shorter than the existing one. That is, about three quarters the length - 87 versus better than 113 miles. The existing line is shown in red, running south.
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The Connecticut Shortcut is envisioned as a mixed use continuous-two-track line connecting New Haven and Providence that is 87 miles long from station to station of which 84 miles would be new construction. There are thirty tunnels totalling 34.2 miles. The longest tunnel is 4.75 miles, located east of the Plainfield station. The highest point on the line is located 850 feet east of the station at Hopeman, at 605'. The lowest point is in New Haven where the line runs for about two thousand feet at an elevation of 5'. The steepest grade is 100' per mile (1.8939393939...%) encountered three times. Twenty-five passenger stations are envisioned between New Haven and Providence, with possibly two express stops initially.
To read the entire description, and download a file to view the Connecticut Shortcut in Google Earth with its elevations and measurements, follow the link:
Discussion of the Google Earth elevations feature follows here:
Elevations are taken from the Google Earth satellite-derived figures which, in at least one instance, have been found more accurate, as to relative local heights in one area, than the the U.S. Geological Survey. Discovery of one such inconsistency has enabled a more sparing use of tunnels and an additional station in Providence - proven out by sighting landmarks in Google Street View available within the Google Earth mapping interface. In Google Earth the elevations shown when hovering the mouse at a given point are always consistent, however the elevation profiles generated by Google Earth are not, having sometimes a lateral error skewed by as much as 400' - in addition to inaccuracies of height independent of the lateral skew. There is some consistency in these errors though, and while GE elevation profiles can never be relied on for getting an elevation, with some fiddling they are indispensable for comprehending the shape of things. Whereas Google Earth and the USGS often agree in other locations they are not frequently together along the route of the contemplated line in Connecticut and Rhode Island. In the interest of consistency - and enabling the above mentioned Providence plan as proven out in Google Street View - I have used the Google elevations throughout.
But this does not necessarily apply where the two mapping systems are more in agreement.
SEEKONK RIVER TUNNEL, PROVIDENCE
The 4.1-mile Seekonk River Tunnel would insure smooth operations at Providence Union Station in future decades. It would also provide a more direct route to Boston for high speed passenger service.
2. NEW YORK
HUDSON TUNNEL PROJECT vs. THE CORRECT ALTERNATIVE
The Penn Station Line would be an extension of the Morris & Essex Line. Continuing east on a tangent where the M&E Line turns south before crossing the Lower Hackensack Bridge, the extension would proceed over a new bridge and through a station with four-way grade-separated interchange, then enter a tunnel directly east of the station leading to Manhattan. In this way the two rail hubs in Manhattan would ultimately have a dedicated station in the Meadowlands providing full connectivity for each: Lautenberg Station, allowing transfer within the station, and Jersey Junction, providing seamless four-way connectivity, with local transit service and parking for Jersey City passengers.
The new line would save four fifths of a mile versus the existing one and more than a mile versus the current Hudson tunnel plan - which doubles back on itself at an acute angle in New Jersey then has to unwind through a reverse curve in the tunnel. (The above drawing is quite flattering versus the Hudson Tunnel Project's actual profile. A more realistic depiction is forthcoming.)
The tunnel envisioned here would be of the two-track single tube variety, allowing nighttime double-stack freight to use a center track straddling the other two. In Manhattan, freight would be processed at an intermodal recycling and transfer facility located along a new, 4-track "West Side Line". Passengers as well as freight would benefit from the tunnel and West Side Line combination, most immediately as a Penn Station alternate in partially-built form, having two four-track stations, at 14th and 23rd Streets - thereby avoiding the necessity of keeping the existing tunnels working full tilt through years of construction and, for a time, of acquiring a large swath of Midtown Manhattan with potential for contentious property issues.
The advantages of the Trans-Hudson/West Side Line configuration are manifold. In the absence of future Jersey-to-Atlantic Avenue service or extension via Brooklyn to Staten Island and Bayonne, an end-point-terminus opposite the World Financial Center, combined with a fully realized West Side Line, would do much to take the strain off Penn Station and the existing north-south transit facilities - with custom tailored trips offering up to six options on the Manhattan side. West Street, opposite and south of the World Financial Center, offers a rare opening for addition of substantial terminal trackage with a strictly limited price in terms of displacements. The end-point-terminus and nascent second-rank Manhattan hub at this location would lend itself well to several supra-regional schemes, including express service to Albany if only they had a train station. But commuter service, both in New Jersey and along the Hudson - including its growing intractable ramifications in Midtown - would stand to benefit greatly in terms of direct access, travel times, convenience and capacity.
The Jersey Junction configuration provides seamless one-seat connection to all commuter rail lines existing or contemplated in New Jersey, plus access to Jersey City and Lower Manhattan by way of the four-track Bergen Arches, the Hoboken Ferry Terminal, and Lackawanna Station with its extensive storage and station trackage. Thus it must be considered as the essential "given" in contemplating any future-oriented scheme for commuter rail in the New York-New Jersey Region - though it would not be necessary to build the whole station/interchange concurrently as a single grand project: a lot of it already exists. Nor is necessary to remove the entire coal-fired Hudson Generating Plant in order to arrange a right-of-way through the property, although there are those who might consider this a good idea. But a plan to make PSE&G whole while introducing modernized generating facilities in a slightly altered configuration is hardly unimaginable.
The track layout at Jersey Junction strongly suggests the shape of an iconic, partially open-air station building about 1000' across. Jersey Junction would obviate the awkward "West Side Wye and Loop" agglomeration planned in Secaucus with it's circuitous, steep grades and dicey low-speed/high-speed timing issues resulting in travel times probably longer than just walking within the station to make a transfer. And (much discussed in terms of how to do it) the Wye-and-Loop does not give access to the West Shore Line, but Jersey Junction does.
It's possible that the twenty-some-mile dual-bore 30th Street Station Bypass proposed in NEC Future documents is a bit much - especially so considering that Philadelphia International is about the only airport in the U.S. with a decent rail connection already in place.
The Philly Shortcut described herein is two miles shorter (5.8 versus 7.8) than the existing line, and has just one big curve, located right next to 30th Street Station. The tunnel is 4.1 miles long and the topography fortuitous. The curve at 30th Street is designed, tentatively, to allow the special track work for the station to kick off near the end of the tunnel, propagating as it crosses the bridge - making for a more interesting bridge. A gifted designer could come up with a suspended, low-slung bridge that would compliment the historical character of the area and its famous buildings with complete appropriateness, and extreme flair.
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The unbeatable advantages of having a station at Camden Yards are obvious, and the route through Baltimore a good deal shorter than otherwise. Two tunnels, of about 4.5 and 3.65 miles, would be required. Lowest point on the line would be under a bridge on West Pratt Street at the indicated "Narrow Channel" - with top of rail around -60. Given sufficient ambition, two tubes with two tracks each might be best along with the suggested stations lying close to the surface east of Camden Yards. A number of stations are possible on an upgraded MARC line south of Camden Yards, including a new station directly on the BWI Airport property where a quick connection to the terminals is possible.
Given the runout of the curve from under West Pratt Street as loosely drawn, four tracks would squeeze nicely by the newer wing of the convention center and the historic Otterbein Church, but not the Federal Reserve. If they decide to rebuild the whole convention center the Fed would be spared, and a superior station and solution for the numerous converging rights-of-way could be realized - assuming an honest desire - and some esprit de corps. In that case the suggested Camden Yards Station could be located about 600' to the south versus the picture, affording harbor views from a big upper level, with a big entrance near a corner of the plaza opposite the long B&O Warehouse, free of trackage.
Given the recent disturbing history of freight in the Howard Street Tunnel there would not be much public objection to taking it by eminent domain, thereby getting the trolleys off the street and tied seamlessly into the suggested Camden Yards high speed rail and transit Knotenpunkt. Of course there is nothing so precious as a historical tunnel, regardless of the intended plans and who pays. Nevertheless, the current freight carriers would do well vouchsafed a gift from the PRR legacy in the form of property rights farther north, with the accompanying design for a tunnel being the best of the bunch. Even with creative planning to make property owners more-than-whole they would still come out ahead.
Bruce W. Hain January 30, 2017
NEW YORK AND SOUTHERN CONNECTICUT
THREE POSSIBLE EXPRESS TUNNELS ALONG THE NEW HAVEN LINE
The appearance of the file "Representative Route Preferred Alternative" - which can be downloaded and viewed in Google Earth - has lent some additional intelligible specificity to NEC Future plans, so an addendum on a few of the affected localities is in order. NEC Future contemplates a number of above-ground high-speed "re-routes" in the area of concern, to supplement the existing line, involving a lot of property acquisition.
While NEC Future's proposal for an additional East River tunnel extending under 31st Street from Penn Station is commendable, the tunnel-and-broad-curve bypass located in Queens, which it would serve, is particularly unlikely of fulfillment - because of a large number of disruptive property issues involved, and because the resulting route is 3350' feet longer than the existing one. (About 6/10 of a mile, or one kilometer.) In it's day the two-mile, eight-track Sunnyside Speedway - which the tunnel-and-broad-curve bypass is designed to circle around - was anything but slow; though speed has been restricted for the past couple of years, ostensibly because of work on the East Side Access Project, and the new interlocking with same will end up slowing it down permanently, to some degree.
With regard to the Harold Interlocking in Queens, the necessary NEC capacity sought through the proposed tunnel-and-broad-curve bypass could more easily and economically be achieved by sticking to the original, readily discernable, expansion plans: four-tracking the connection of the Hell Gate Line at Harold - where several tracks of the LIRR underpass and the Hell Gate return track were located conspicuously on the perimeter, in order to enable easy construction and expansion of the necessary concrete box bridge structure - with no effect on existing service whatsoever.
The configuration that exists today, reduced now to two tracks on the four-track Hell Gate Bridge, saved a lot of then-unnecessary trackage when it was opened in 1917. Another capacity-enhancing modification no doubt envisioned at the time: putting the Port Washington Branch flyover in Woodside where the line actually diverges, rather than having a separate two-track line running the 1.4 miles from Harold to Woodside. This would allow four mainline express tracks at Woodside Station, should the need ever arise, whereas it is currently configured as two separate stations: one for the four-track Main Line, and one for the two-track Port Washington Branch.
Rather than using the originally planned four-track Hell Gate connection at Harold, as one would expect, the current work-around-in-absence of the proposed tunnel-and-broad-curve bypass consists of two "Amtrak Bypass Tunnels" - one of which was supposed to have a 1000' bored section at one time, but was later revised at some point over the past ten years, before construction began. The likely curving alingment and trackwork needed for accessing these Amtrak tunnels will likely succeed in slowing things down still further - though no definitive drawing showing the two Amtrak Bypass Tunnels has been made available for public consumption.
Heading north, between New York and New Haven there are four major time-saving improvements that strongly suggest themselves, two of which could be considered mandatory for achieving speedy Northeast Corridor passenger service and providing a modernized upgrade to part of the existing line. The first of these is the grade separation project at Shell Interlocking in New Rochelle, where the Grand Central and Penn Station lines meet.
The NEC Future concept for grade-separation at Shell is good, I assume because they’re going by earlier drawings. But the specific alignment, obscured by the vague 150′ width shown throughout, is overly optimistic by a lot in terms of possible curve straightening, and creates conflicts that would not be allowed because of the historic structures, having also a big conflict with Route 95, and the necessity of moving the existing New Rochelle station to a different place. Best to stick with the earlier assessment of 60mph through the connection on the Hell Gate route, which after all would be a big improvement.
RYE-GREENWICH EXPRESS TUNNEL
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Working northward, the first abbreviation strongly suggested by the existing layout would take the form of a single-tube two-track tunnel running between Rye and Greenwich. Your commenter does not consider this particular upgrade to be mandatory, since the general heading of the old New Haven Railroad is quite direct notwithstanding curves included when the four-track upgrade was opened in 1900 - largely a result of routing the line through a succession of built up areas, in hilly terrain, and the necessity of having the bridges as short as practicably possible.
The 3.34-mile tunnel bypass contemplated here would serve to avoid a notoriously slow curve at the state line in Port Chester, and would skip the Rye and Port Chester stations. The problems of connecting tunnels or any shortcut smoothly to an existing line are compounded here by the tracks being spaced twelve feet apart. This obtains on most curves as well, including those upgraded since 1900, and would rule out tilt technology in most instances without widening the New Haven Railroad to more modern standards. (So, assuming tilt technology is to be employed, any high-speed upgrade of the Northeast Corridor should include tilt-compatible upgrade of all curves included in the high-speed routing, to avoid the necessity of using the tilt technology selectively, which would introduce some additional degree of risk.)
This type of issue also requires having anything new commence at a point where there is sufficient space to allow the connection, and, combined with achieving acceptable grades, has a tendency to make the tunnels longer than they might otherwise be. The two more-cursory drawings shown here depicting proposed Rye-Greenwich and Stamford-Westport passenger tunnels do not include the trackwork of the approaches, which in most instances must be propagated to six tracks in order to accommodate the tunnel line entering or exiting. However, in all instances considered here there is room for widening of the line without resorting to demolition or, apparently, any acquisition of property.
Starting west of the station at Rye, the tracks would propagate to six, coming off the last curve at Harrison, in order to get the two center ones into the tunnel, with liberal choice as to where along the long tangent section. The tunnel would alter its heading about 3.5 degrees from that tangent, near the station at Rye, then follow the new heading right across the Byram River, which it would cross beneath, along with the shopping mall and it’s parking lot at the center of Port Chester. The bottom of the river is probably a maximum ten feet below the datum plane, so top of rail could likely be around -55′ assuming a single tube with about 40′ outside diameter, avoiding the mall and likely any other subsurface structure.
So far we’ve avoided any residential property or acquisition. And being down below the river stands us in good stead for getting under the next residential uprising, which is quite a bit higher than the riverbank. The tunnel would take a second turn, altering its course to the heading of the tangent segment running alongside the turnpike (about 8 degrees of central angle) before running under it for quite a ways, to get up to the level of the tracks. The connecting process would be enabled by a six-track configuration having a mirror image of the one at Harrison and running off the last curve before the Greenwich station. It’s not possible for the new two-track line to be too low under the said tangent segment, in order to stick to a reasonable grade, amid likely sogginess since the existing line is cut into the side of a hill, running between it and the turnpike, but it should be as low as possible under the houses to the south.
Thus, a pretty much bolt-straight tunnel 3.3 miles long having a vertical curve in the middle running under the river, with a 1.2-percent grade to the south and a 1.3 one to the north – modifications of that to get a lower grade under the houses being improbable, with the worst one being about 100′ above top of rail – and they’re small. The shortcut would take 4/10 of a mile off the existing route, and the new alignment could be negotiated at high sustained speed.
The curve before the Greenwich station has a radius a thousand feet longer than that of the notorious one at Port Chester. The idea of straightening curves like that amidst some of the most expensive real estate in the world - or the ones around Green's Farms which are a bit broader - is not in keeping with a realistic outlook, especially if intrusive acquisition is necessary to achieve it. The expense of construction, and the complications of building speedy connections to these still not-very-direct alignments is not worth the bother, nor are the numerous nightmarish turnpike alignments. It is difficult to discern what planners are trying to achieve by suggesting these things. Both stretches in their existing form, around Greenwich and Greens Farms, make for a varied and enjoyable ride, passing through the bucolic countryside, at reasonably high speed.
STAMFORD-WESTPORT EXPRESS TUNNEL
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The second optional tunnel would begin in Stamford. Proceeding east from the Stamford station in six-track configuration - which would require considerable rearrangement at and around the station to enable it - an approximately 1.95% descending grade of the two center tracks would commence at Atlantic Street and enter tunnel configuration at Canal Street, which would require drastic realignment of the street's vertical profile or permanent closure of the part that passes under the tracks. The express tunnel would diverge from the existing main line on a tangent at Elm Street (where the latter veers north onto one of its lengthier detours, to meet the New Canaan Branch) and then follow along the same heading 1.3 miles to the Noroton River, where it would turn slightly to the north.
The 8.8-mile express tunnel would then follow this new heading for the next 5.5 miles, till it reaches the Norwalk River. An alternate 3.3-mile version starting in Stamford has been considered, but would require a higher profile under Noroton Heights to meet the existing line in Darien, as well as acquiring part of a waste disposal site to build the connection there. Combined with the expensive alterations necessary in Stamford regardless of tunnel length this would suggest that the longer version is preferable. Owing to topography and space considerations, the first opportunity to make the connection after Darien is Westport. A tunnel with optional exit/entrance at Darian was found to be unfeasible, but the long tunnel would reduce the mileage and skewed headings of the existing line considerably.
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The structural-stone-clad and grade-separated main line of the New Haven Railroad that opened in 1900, with it's electrification completed to Stamford in 1907, was the world's first long-distance high-speed electric railroad to use overhead wires for its power source, and was followed quickly by other entries worldwide along the same lines. The exigencies of it's design, being threaded through built-up areas along the now nearly conurbated Connecticut coast, and constrained by both hilly topography and the many river crossings, presented difficulties that would seemingly be insurmountable today, despite the computerized positioning and detailed information on topography and geology available without even a survey that is now at planners' fingertips - add to that the pushbutton ease of instantly drawing logarithmic track geometry.
Starting at lower left in the picture, three new below-grade stations have been added along Railroad Avenue in conjunction with eliminating the Chinese Wall in the middle of the street. The structural sandstone blocks made available by such a conversion, this being one of a number of them possible along the line, could be used later - being reduced to facing stones and thereby multiplied - in rail construction where aesthetics is a concern and local or regional conformity is desired, as mentioned above in the main part of the comment. Opening of the new stations - which are only 2500' apart - could be implemented as the need arises and smoothly enabled for high volume through means of skip-a-stop service. The street is 125' wide and the new configuration would make it a desirable place for development.
The new vertical alignment would start 2200' west of Fairfield Avenue at the Ash Creek bridge (not shown) and pass below grade at Fairfield Avenue, with the station there being of the open-air type to the west only. A dip was introduced in the avenue when the existing railroad bridge was built, and realignment implemented with the new changes would make it about level. Proceeding east, the new alignment passes under the Connecticut Turnpike at the proposed Garden Street station, beneath which the two express tracks pass to one side in advance of the split-up at the main station in Bridgeport.
The section of the turnpike beneath which the line would pass runs partly over bridges and partly on embankment. Although expensive, the result of the necessary staged construction would finally remedy the oppressive effects of both the massive elevated roadway and the tracks with their catenary wires, which have been in evidence for a long time. An extensive flat spot deep under the road is set out for an emergency crossover in conformance with both AREMA's fifteen-foot spacing and Amtrak's 2013 rule on reverse curves. The sharp curve on the existing line at center (above, black) with a central radius a thousand feet shorter than that of the "notorious" one at Port Chester (i.e. 750') - likely so positioned in an effort to assuage the railroad's debt to the NIMBYs of the day - would at last be relegated to the scrap pile.
STATION AND TUNNEL
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Your commenter has not been able to detect any NEC Future proposal for avoiding the extreme and circuitous geometry at Bridgeport, though has heard mooted a bypass that would avoid any station there at all, Bridgeport being Connecticut's largest city. The "Representative Route Preferred Alternative" follows the existing extreme alignment both at Bridgeport and surprisingly at New Haven too, where the existing New York-to-Boston Main Line runs approximately-due-south for six consecutive miles along it's northbound leg to Boston.
The low elevation under the Pequonock River (center) is mitigated to some extent through use of two separate tunnels at this point, though the bottom of the navigation channel is actually not 35' below the datum plane (the specified dimension) and a lack of prospective shipping traffic might afford a somewhat higher profile. As shown, the express platform is about 75' below the curb at it's deepest point, where it's about a hundred feet wide, right before the tunnel. It's not unlike a number of subway stations in New York.
It would be interesting to have the express platform open to some overhead light where it's not under the road, with the local platform located about 95' higher at its north end and 15' at the south. An open-plan station with glass outside walls would make for an interesting space, with the platforms visible from one another and accessible interchangeably through the interior of the station. A glass wall on the northwest (local) side would dispel the crummy feeling of being in the shadow of the gargantuan highway-on-stilts at it's highest point - in this otherwise choice part of town - and the road's overhang might act as an elongated porte cochere.
Although there may have been or might someday be plans to straighten the turnpike by removing the 90-degree bend that crosses the Steel Point Peninsula it is not likely any time soon, as this would compromise accessibility of Steelpointe Harbor, the first and best new development in Bridgeport for a long time. Although they lost an anchor tenant once, talk of a new casino opposite the peninsula to the east is heating up, and they own the property. It remains only for the state to make it legal in order to proceed, so it's only a matter of time before the peninsula will be inaccessible for purposes of building the Bridgeport upgrade and tunnel as described here. This is by far the most important of the three projects in this addendum, and because of it's truly time-sensitive nature it may be the most urgent of the many important NEC projects now being considered. A realization compromised by the failure to act would have permanent negative consequences for all concerned. Amtrak should be made somehow to realize this and seek an option or something with the developer as soon as engineering can be solidified. The resulting displacement of other uses would of course be temporary.
MODIFICATION OF THE EXISTING LINE
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(Although it doesn't look like it, the long tunnel starting at left would use a single tube past about the middle of Steel Point Peninsula. The tracks are shown 15' apart. This should give some idea of the kind of work necessary on location to bring it about.)
Going north from the local platform of the proposed Bridgeport station, the two local tracks would split into three as they pass onto the elevated stone conduit which currently carries the four-track Northeast Corridor Main Line. The line here is shown reduced to three tracks, for two reasons:
The three-track configuration allows the western-most track to be used for a platform at the Bridgeport Transportation Center, without modifying the existing configuration of the recently built bus-transfer-and-station facility. The fourth track of the bridge would still be usable for non-passenger-service purposes, or in emergency.
Also, at upper left in the picture, and passing toward the Barnum station at right, a new alignment is suggested because of the intrusiveness of the existing one, encroaching as it does on one notable church property lying to the north (540 E. Washington Avenue - originally a synagogue built in the 1840's) while yet running too close to the Catholic Church and grounds to the south. Reducing the stone conduit to a width of 40' versus the current 65' in the area east of the recently rebuilt section (part of the Pequonock River Bridge rebuilding project) and redirecting it slightly as shown, would provide considerable relief.
And, if certain rather vague drawings in documents of the new Barnum Station are to be believed, current plans call for making the four-track line encroach still further on the already narrow Crescent Avenue - which is shown above as a landscaped, four-lane boulevard. While the structural stone conduit for the tracks is already about 3' from the church building on the north side - so can't be moved any closer to it - yet it cramps the one on the other side as well, constricting the parallel Crescent Avenue and confining it flush against the stone conduit. The new alignment would get the tracks out of the way and allow development of a pleasing regional rail station to the east, with spacious entrance plaza.
The station itself could be either 3 or 4 tracks, with the platforms as shown being 950 and 1250 feet long. The area behind the station might serve as a sort of pedestrianized half-street with outdoor cafe seating surrounded by taller structures, with a broad central walk leading to Barnum Avenue. Versatile double-ladder access is shown at the west of the storage and maintenance facility, in the event the capacity is someday required.
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It's impossible to locate the northern connection of the tunnel from Bridgeport in Stratford because there is a broad low spot in the way to the west. No connection involving the low spot is possible because there's no way of getting to the tracks. Besides, the grade from any location in the vicinity needed to access a proper Housatonic River Bridge would be too extreme, and would additionally require a long elevated and ungainly structure over land to accomplish it. So it is necessary to proceed across the Housatonic River before the topography avails itself, to get to the surface.
Although the pictured spot in Milford is likely to be best it's not perfect. Rising along a dignified gradient from under the Housatonic River located off the picture to the left, the upward impetus quickens through a vertical curve at the -30' pushpin marker (green) by a Motel 6. From there it rises at about 1.9% though the estuarial meadow at center - which might require some heroic measures in the form of deep piles and isolation form the water - before meeting with the straddling main line. Measured from the front of the station at Bridgeport the tunnel is 6.46 miles long.
Bruce W. Hain February 22, 2018
BARNUM STATION SET BACK FROM THE ROAD
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