Oh, Boston, you're my home"
The Standells, 1965
Some 600 million years ago, a chain of volcanic arc-islands and related arc-basins rifted from the northern margin of the massive South Hemispheric continent of Gondwana. In particular, the Avalonian arc and Boston Basin initiated a transequatorial tectonic journey across a closing Iapetus Ocean and welded to Laurentia, the North American craton. Following Gondwana's amalgamation, the terrane and basin became landlocked within the Appalachian orogen of Pangaea in the late Paleozoic. They achieved a seaside locale in eastern Massachusetts only after the supercontinent's fragmentation and initiation of Atlantic seafloor spreading in the Mesozoic.
Today, the Boston Basin is a fault-bound, tectonic lowland filled with volcanogenic sediments surrounded by resistant highlands and contains Greater Boston and its harbor. After the final retreat of the continental ice sheet some 14,000 years ago, the landscape directed the Charles River system to the sea. As little as 175 years ago, Boston's Back Bay was mired in malodorous mudflats at low tide within an embayment of the river estuary. The time had come for man to re-engineer the natural landscape. If Back Bay was ever to become the urban showcase that it is now and persuade the Yankee elite to remain in town, more habitable land had to be created. But how, with what and from where?
For the interest of everyone familiar with the city, I have included present-day landmarks parenthetically. This is the first post of two on Back Bay's geological journey, only in reverse order.
Part I - The Filling In of Boston's Back Bay
Part II - The Geological Evolution of Back Bay's Boston Basin
WHERE IS BACK BAY?
Ask any Bostonian. They'll delineate Back Bay by its boundaries with Arlington Street on the east at the Public Garden (they might even include the Public Garden), Charlesgate on the west (near Kenmore Square), the Charles River on the north (along Storrow Drive) and the tall buildings of Boylston Street on the south. But, they'd only be partially correct.
Back Bay is considerably larger - more than twice the area - if you include land created by filling in the shallow embayment of the Charles River on the "back" of the bay, the assumed derivation of its name. That would extend it further south to a narrow isthmus of land that once connected the pendulous peninsula on which colonial Boston was located to the mainland.
Don't look for signage. It's probably not there. Don't try to drive. The one-ways go in the wrong direction. Now you know the meaning of the New England phrase, "You can't get there from here." Lost and confused? Use your GPS. Plug the following co-ordinates into any online mapping program such as Goggle Earth and travel to the center of Back Bay: 42°21'04.73"N, 71°04'49.31"W
A TALE OF TWO CITIES - ONE OLD AND ONE NEW
Since its establishment, Boston has increased in size dramatically. It's easiest to grasp the magnitude of growth on a map of the 1630 city superimposed on a map of the modern one. Surrounded almost entirely by water, everything outside the old city's shoreline is land that has been created by filling in between wharves and within dams and seawalls to a level above the high tide. Everything within (light brown) denotes land of the original Shawmut Peninsula including the Neck to the mainland.
Titles in red are many of Boston's annexed towns, neighborhoods and districts. Take special note of the Mill Dam, "Cross Dam", and Beacon and Washington Streets. Their histories are important in the evolution of the early city and later Back Bay.
The modern city of Boston, which has an area of 89.6 square miles, remains 54% land and 46% water, even with its history of extensive landmaking! Boston has always had a unique and intimate relationship with the sea, while Back Bay has had one with the Charles River. Surely, the sea and river have directed the evolution of both, in part, the subject of this post (with lots of history thrown in).
|Maps Displaying Boston's Growth Between 1795 and 1912|
Whether by annexation or filling in land, the area of Boston has increased exponentially.
Modified from radicalcartography.net
WHAT IS BACK BAY?
It's an officially-recognized neighborhood of Boston, having been reclaimed from shallow estuarine wetlands - tidal mudflats and salt marshes of the "Charles" - beginning some 175 years ago over the course of 100 years. Although many waterfront cities are built on filled in land, likely Boston and certainly Back Bay have more than any city in North America.
Back Bay's residential district is immediately recognizable by its uniformity, lack of high-rises, rectangular shape paralleling the river, orderly grid of gas-lit streets lined by rows of architecturally-significant nineteenth century churches and buildings, and its Paris-inspired, broad Commonwealth Avenue and tree-lined mall running down the center. On Back Bay's south side, the commercial district is the "High-Spine" of buildings, fashionable shops and galleries of Newbury and Boylston Streets.
|A Welcomed Sign of Spring in Back Bay - Dogwoods and Magnolias in Full Bloom|
From Andrew Harper
You'll repeatedly hear the same adjectives used to describe Back Bay (especially in real estate ads with prices that are through the roof) - upscale, unique, prestigious, civilized, historic, elegant, serene, fashionable, trendy, chic, sophisticated and affluent. What's interesting about Back Bay is that it isn't one of those parts of a city that acquired those descriptives over time or by urban renewal or radical makeover; it was that way from the start by intent. It was filled in and built up using a carefully planned design that was motivated by political, sociological and geological factors.
WHAT WAS BACK BAY?
Only 175 years ago, Cambridge and Boston were separated by nearly two miles of river water flowing gently to the sea and thousands of acres of brackish-water wetlands. The Charles River "was" an estuary with a free connection to the open sea and received an in-flux of salt water from the Boston Harbor twice daily. The region that Back Bay now occupies was formerly an embayment of the Charles River.
Larger than a cove but smaller than a bay and before filling in, it was bordered by foul-smelling (although natural) mudflats punctuated by braided streams and a salt marsh, flooded and drained by saltwater brought in by the tides. Various transgressions of the growing city heightened the people's awareness of the mudflat's odors.
|A Typical Estuarine Salt Marsh and Mudflat|
Back Bay was constructed in the nineteenth century above the level of the high tide to minimize the risk of flooding. These days, the river is officially the Charles River Basin. Flood-controlled, placid, lake-like and no-longer free-flowing into the sea, the river was impounded at the mouth by the Charles River Dam erected in 1910 and 1979 (although in the course of the river's history numerous mill dams existed upriver). That virtually eliminated the tidal mudflats and tidal flux of the river estuary (not so upriver where it's punctuated by numerous thriving wetlands), although denser cold water still enters the basin through any of three locks in the dam that are opened for navigation.
WHAT'S IN A NAME
Back Bay's parent Boston lies on the Atlantic Coast of eastern Massachusetts where the Charles River meets the sea. It's the 48 square-mile capital of the Commonwealth of Massachusetts, designated as such by the English for the "common good" and a reminder of the colony that England ruled before 1776.
The city was first called Trimount, alluding to its three dominant hills, all drumlins of glacial origin. They have since been either whittled down or completely eradicated from the landscape to fill in various parts of the city. Boston was renamed by the Massachusetts Bay Colony, whose most prominent members were from Boston, England, a small port in the county of Lincolnshire. It explains the derivation of the town names scattered throughout New England.
As early as 1858, Boston was referred to as the Hub of the Solar System or simply "The Hub"(referring to the gold-domed State House and coined by poet Oliver Wendell Holmes, Sr.). Other monikers include Beantown (of debated origin), Titletown (goes without saying), Athens of America (a city of educated, spiritual and cultural guiding-members), the Cradle of Liberty (all those revolutionary events), America's Walking City (with its many neighborhoods and Freedom Trail) and the shining "City Upon a Hill" (from Jesus's Sermon on the Mount and delivered aboard the sailing ship Arbella by John Winthrop to his Puritan shipmates on arrival to the New World). The "hill" refers to the glacial landforms of the peninsula (and everywhere in the Northeast) and Winthrop's idealistic vision of the New World.
LAY OF THE LAND
The Shawmut Peninsula...
Almost an island, the 789-acre peninsula that the Puritans first settled pendulously jutts into Boston Harbor. It was called Shawmut by Algonguin-speaking Native Americans, possibly of the Massachusetts tribe. The name is thought to be derived from Mashauwomuk, which may allude to the saltwater that surrounds the peninsula or the freshwater springs that enticed the Massachusetts Bay Colony to settle there. It was defensible, well forested, dotted with hills and graced with the necessity of freshwater. Water and geology have always been a factor in the evolution and destiny of the city of Boston.
As the population of the new settlement grew within the confines of the peninsula, it developed its famous and infamous, haphazard arrangement of streets that still exists today, some 400 years later. The narrow and crooked "cowpaths" - a myth initiated and now perpetuated in a poem by Oliver Wendell Holmes, Sr. - remain the bane of confused drivers and lost sightseerers in the oldest part of town.
The confusion is apparent in a photograph taken from a hot-air balloon in 1820. As more space on the peninsula was needed, "wharfing out" was employed, which consisted of filling in the slips (or docks) between wharves as they were extended, which gradually increased the dimensions of the city circumferentially. In time, Bostonians looked to the embayments and coves around the peninsula to create space to grow.
When Boston was first settled in 1630, the peninsula was connected to the mainland by a narrow, rather tenuous low-lying isthmus of land called The Neck. It united the colonial city of peninsular Boston to the mainland at the town of Roxbury. Only 50 to 100 feet wide in places, it frequently flooded in storms and was threatened at high tide. As early as 1735, wooden "wharffes", and by 1790, stone wall dams were erected to hold back the sea.
There was room for only one road across the Neck from Boston to the mainland at Roxbury. It went from from Cornhill Street to Marlborough to Newbury and finally Orange near the mainland. After the American Revolution, in honor of George, its names were unified into Washington Street with street names that cross it changing their names out of respect. It was the Commonwealth's longest street and continues through Roxbury to the Rhode Island state line. It's roughly paralleled by the tracks of the MBTA's Orange Line that inherited its name from Orange Street.
As for the town of Roxbury, like so many others that surrounded Boston, it was annexed in the nineteenth century, 1868 for Roxbury. The "dissolved municipality" is one of 23 others (including Back Bay that was later "created") that are now official neighborhoods of Boston.
Boston's famous and infamous river was named by the Prince of Wales, soon to be King Charles I of England. New England's waterforms and surficial landforms are products of the last advance and retreat of the late Wisconsin Laurentide Ice Sheet that flowed through the region between 30 and 15,000 years ago. It left a thick blanket of unconsolidated till, outwash sands and gravels, and glaciomarine clays and silts, some of which formed prominent drumlins and eskers across the landscape that played a role in the creation of Back Bay.
With a watershed of 308 square miles and flowing through 35 cities and towns, the lazy Charles River makes its way to the sea. Roughly within Route 128 (currently I-95), the ring-road that surrounds Greater Boston, the river enters the Boston Basin and erodes through bedrock of the Cambridge Argillite (much more on that in post Part II) that floors the city and Back Bay (much more on that in post Part II). Before emptying into Boston Harbor, the unimpeded River Charles flowed between Cambridge and Charlestown on the north and the Shawmut peninsula and its Neck on the south.
South Cove and Bay...
Immediately north of the Neck and west of the peninsula lay salt marshes and mudflats exposed at low tide sliced by braided networks of stream channels of the river estuary. Originally 737.5 acres in extent, the bay was unequally divided by a small promontory called Gravelly Point (in the vicinity of today's Massachusetts Avenue) that left the largest portion to the east. The embayment eventually succumbed to the the city's growing pains by being filled in as did the cove on the south side.
On the south side of the peninsula, between The Neck and Dorchester Point/Neck were South Cove and South Bay. After filling in that began in the late eighteenth century, the area became the Leather District, Chinatown and the confusion of "Big Dig" ramps to Fort Point Channel, which is a stunted river-like remnant of South Bay.
FIRST TO MAP
Captain John Smith of the Virginia Company of London explored, mapped and named coastal New England and many of the bodies of water from Penobscot Bay in Maine to Cape Cod, Massachusetts in 1614. The newly-penned River Charles emptying into an island-studded, as yet unnamed Boston Harbor appears on his map. He surely must have seen Boston's many hills from Boston Harbor.
A young Charles, Prince of Wales, the future King Charles I, provided much of the region's nomenclature, most of which does not survive today. Notable exceptions are the River Charles, Cape Anne and Plymouth. Boston appears on this pre-settlement map, since its the ninth to have been produced. It provided much of the incentive for the English to settle in eastern Massachusetts in the following decades.
FIRST EUROPEANS TO SETTLE
The dissenting Anglican priest William Blackstone first settled on farmland of the future Boston Common. He invited the group of Puritans that had settled on the peninsula across the river in future Charlestown (another neighborhood of Boston) in 1629 to make the switch in 1630, since the only freshwater spring was accessible at low tide. They were Protestants escaping the sins of Stuart London and seeking a reformed or "purified" form of religious freedom in the New World under the leadership of John Winthrop, lawyer and first governor of the Massachusetts Bay Colony.
Blackstone eventually departed for Rhode Island, weary of their intolerance of anyone that disagreed with them in spite of their intolerance of the Church of England. On the land that Blackstone had vacated, the Puritans established the city of Boston.
CUTTING DOWN SHAWMUT'S HILLS
One of the earliest land reclamation projects that Boston undertook occurred in the 1640's, soon after the colony had been settled. It's relevant because of where the earthen material came from, how it affected the landscape and the precedent that it set. It began with a large cove that was dammed off on the peninsula's north side and converted to a reservoir. It supported a number of grist mills for grinding corn and wheat into flour, distilling rum, sawing lumber and even milling chocolate.
They were tidal mills - powered by the slow release of river water from Mill Pond at low tide that entered from sluices of the West Floodgate at high tide. The concept dates back to Roman times on the River Fleet in London. Once the tide periodicity was predicted, it became a renewable energy source free from drought and with saltwater that didn't freeze in winter.
But by the end of the 1700's, the mills had become unproductive and left to deteriorate, while the pond had become sediment filled, polluted by wastewater and seepage from residential privies and a "capacious receptacle and reservoir of all the filth and putrescent substances of (the) town....covered with the putrid bodies of dogs, cats, and other animals...offensive and unhealthy." The townspeople rightfully considered it a health risk in the common notion at the time that diseases occur from noxious vapors or miasma. Malaria is a classic example, which means "bad air" in Medieval Italian.
FILLING IN THE POND
After seven years of debate, the solution was to fill in the pond in spite of losing its "cheering westerly breeze." In 1807, the project began by "cutting down" Boston's hills. The initial contribution came from a portion of Copp's Hill in the North End (a stone retaining wall marks the site alongside the 1659 North Burying Ground). By the early 1820's, much Trimountain's three peaks had succumbed, largely from the middle and highest called Beacon Hill.
The excavation was accomplished with hand tools and transported via horse-drawn tip-carts to the Mill Pond. The 21 year project added some 50 acres of land to Boston at Mill Pond and was the beginning of Beacon Hill's diminution but not elimination. The story of Boston's missing hills is part of the story of the creation of Back Bay.
For familiar Bostonians, the filled in cove lies between the West and North Ends and the Government Center Garage to the TD Boston Garden and North Station Rail Terminal, which are just outside the dam. Causeway Street was built along the embankment of the Mill Dam, while Canal Street runs along the site of the intended connection with the Charles River. Now a historic district, the Bulfinch Triangle has preserved its original street design for residential, warehouse and commercial use.
THE FILLING IN OF BACK BAY
Most Bostonians are aware that Back Bay resides on filled in land, but the perception is that the official process was initiated in the late 1850's. Although it's technically not a part of Back Bay, the project actually began immediately to the east of Back Bay at the site of the future Public Garden. Surprisingly, it was precipitated by a seemingly unrelated catastrophe on the opposite south side of the peninsula.
In 1794, seven ropewalks and 96 buildings burned down at Fort Hill, one of the region's many glacially-derived hills now long gone (the site of present International Place). Ropewalks were long and narrow, usually wooden buildings where men walked backwards while twisting spun hemp into rope, essential for Boston's fleet of sailing ships to secure anchors and rigging. Dry hemp dust often ignited by open flames of tar vats used to make rope more water-resistant. As a result, ropewalks frequently burned to the ground with everything around them, which is why they were allocated to the outskirts of cities.
Following the fires, the ropewalks were relocated to the western side of the peninsula at the foot of the Common (red ellipse). To accommodate the construction of the 700 to 900 foot-long buildings, a seawall was built to facilitate the filling in of the adjacent wetlands. But by 1822 and numerous fires that had struck again, the city, concerned about proximity to the Common, acquired the ropewalk land and adjacent mudflats used for dumping trash and soil.
|1805 Map of Boston Showing Ropewalks at the Foot of the Common|
Separated from the Common by Charles Street, the ropewalks were built on made land from wetlands on the west side of the peninsula.
After a lengthy debate as to whether the acquisition should be developed for residential use, annexed to the Common or remain "open and free" to bathe the city in "a constant current of fresh air", the city, in 1825, approved taking earth from nearby Fox Hill to fill in the ropewalk land and grade it down to the river. Unknowingly, land was created for the new Public Garden, which also was the "unofficial" beginning of Back Bay in a manner of speaking.
A PUBLIC GARDEN BEGINS TO FLOWER
Established in 1837 when philanthropist Horace Gray petitioned for the use of the land, it's the first public botanical garden in the United States. The Public Garden is incorrectly regarded as part of Back Bay. It's actually an independent entity separated by almost 200 years of creation by Arlington Street, the first cross street of Back Bay. Its 24 acres are criss-crossed with strolling paths, brightly colored flowerbeds, happy ducks (both alive and statued) and a suspension bridge over a lagoon replete with swan boats.
With the Boston Common immediately to the east that predates its establishment and the Commonwealth Mall to the west that postdates it, they comprise the northern terminus of Central Park architect Frederick Law Olmsted's "Emerald Necklace." It's an 1,100 acre, seven mile-long chain of eleven connecting parks and waterways throughout Greater Boston that "hangs from the neck" of the Shawmut peninsula. Several components of the Emerald Necklace pre-date the plan to unite them.
|The Tranquil Lagoon of the Public Garden|
Upon visiting this sublimely serene and idyllic enclave in the middle of the city, it's hard to believe not only that it's in the center of town but that it was once submerged beneath a shallow, muddy edge of the Charles. It's reminiscent of beautiful Parc des Buttes-Chaumont of Napolean III in Paris that emerged from a bleak gypsum quarry and refuse dump for sewage and horse carcasses. You can read about it here.
Proof of submersion are 4, to 5,000 year-old staked remains of fish weirs discovered during construction of the Boston Common Parking Garage across from the Garden. Native Americans used the ebb and flow of tides in the Charles estuary to entrap fish as brackish water flowed back to the sea, just as the mill dams harnessed the tides to power textile mills. They would be used once more in Back Bay before its filling in.
THE SECOND MILL DAM OR THE INDUSTRIALIZATION OF BACK BAY
Reminiscent of the Mill Pond, Back Bay's filling began as a power project, when, between 1818 and 1821, an ambitious dam was built by the Boston and Roxbury Mill Corporation. The one and a half mile-long Great Dam extended across Great Bay - the embayment of the Charles River - from the foot of the Common (intersection of Charles and Beacon Streets) on the east to Sewall Point in Brookline (Kenmore Square) on the west. It was intersected by a shorter cross-dam that ran from the low peninsula of Gravelly Point (today's intersection of "Mass" and "Comm" Avenues).
The two dams divided Great Bay in two. Upriver on the west was Full Basin that received water at high tide through five pairs of floodgates. Water was then shunted through sluices to power mills located on Gravelly Point and then through raceways at low tide to a larger Receiving Basin downriver (the part that is known as Back Bay), and finally back out to the main river. The intent was to power the mills to serve and give Boston a competitive edge over steam-powered mills in New York and Philadelphia, while costing less than obtaining items from Europe in short supply from the War of 1812.
The 50 and later 200 foot-wide Great Dam housed Western Avenue, which was the forerunner of today's Beacon Street (much of the dam is buried beneath it). Originally, Beacon Street only ran a short distance down Beacon Hill next to the Common as far as the waters of Back Bay but later linked colonial Boston with Brookline to the west as did Washington Street with Roxbury 200 years before. In the mid-1840's, the BRM Corporation added a short seawall at the Boston end of the dam that increased the width of the Mill Dam. Eight adjoining houses soon followed. Back Bay was starting to populate!
In the 1820's, railroads began to appear in Boston. Inspired by the advent of steam-powered railroads in England and the horse-drawn railroad locally that brought blocks of granite down from the Quincy Quarry for construction of the Bunker Hill Monument in Charlestown, they came from Lowell, Worcester, Providence, Maine and New York. By the end of the nineteenth century, eight separate railway terminals existed in Boston, which were consolidated to two. Rail lines criss-crossed the Charles on elevated embankments as they heading to the flats north of Causeway Street (the site of the Mill Pond at today's North Station), from the south (at South Station, which coincided with final landmaking in the South Cove in the 1890's) and the future Back Bay.
The railroads were highly welcomed in the commercial competition that was developing with New York, Philadelphia and Baltimore. They not only became the principal reason for creating land in the second and first halves of the nineteenth and twentieth centuries (largely at the expense of Mount Pemberton, Trimountain's easternmost peak), but the railroads were the means by which Back Bay was filled in. Without them, the task would have been far more laborious and lengthy.
HISTORY REPEATS ITSELF, YET AGAIN
In the mid-1840's, it was clear that tidal power and the capacity of the Receiving Basin were insufficient. The Corporation had envisioned some 81 mills and a major industrial district, but only four were operational at one time. Worse, damming impeded the river's natural flow and beneficial tidal flushing twice daily as did the network of railroad embankments that "roofed the river" in addition to interfering with navigation. The entire situation was worsened by the spillage of raw sewage and the dumping of waste.
Back Bay had become a "great cesspool (with)...a greenish scum"...whilst the surface of the water (was) bubbling like a cauldron with the noxious gases...exploding from the corrupting mass below." With an 1849 cholera epidemic in the overcrowded and unsanitary Fort Hill district fresh in the minds of the townspeople, the perceived health hazard was real.
With metropolitan Boston's population increasing (571,789 in 1850), the more profitable and productive use of the tidal mudflats was to convert it to habitable residential land. The small and confining Shawmut peninsula of old Boston had fulfilled its requirements of a defensive position, a high point for the location of a beacon to warn ships at sea, and freshwater springs and wells. But in 1850, overcrowding occurred as the population quadrupled in 40 to 50 years.
Two solutions to the problem became obvious - either improve the bay's drainage or fill it in and convert the "putrid worthless marsh" to "solid and wholesome dry land" with "clean gravel" rather than with perceived unclean, clay-rich (poorly-drained) dredged river mud. The latter option was agreed upon, but, there was another reason - a covert one that was both political and sociological in motivation and related to Irish potatoes.
GROWING PAINS AND EMIGRATING IRISH
Starting in 1845, a virulent fungal blight devastated the potato crops in Ireland. It deprived Irish families of their main source of food and subsistence and was responsible for over a million lives lost from famine and another million that emigrated to America (read about it here).
In 1847 alone, 37,000 Irish refugees landed in Boston on the edge of death and despair, which almost instantly made the Irish a quarter of the city's population. The development of the South End, in addition to providing more living space, was an attempt to encourage members of the upper middle-class to remain in town as tax payers and voters to counter the arriving masses of impoverished and struggling Irish Catholics - unskilled, unemployed and unwise to the ways of city life. But things changed in the 1860's when the desirability of many neighborhoods including the South End diminished for the city's Proper Bostonians, who would became increasingly attracted to the grandeur of Back Bay.
FILLING IN THE BACK OF THE BAY
Filling in the tidal mudflats of the Charles was a concerted but not always seamless and cooperative agreement between the city (such as the Boston Water Power Company), the state and various commissions, flat owners, entrepreneurs and corporations (such as the Boston and Roxbury Mill Corporation) that had a vested interest in its establishment. What was needed was agreement of the interested parties, a design for Back Bay, financing, a plan for filling it in, a source of earthen material and a means of getting it there.
In the beginning, the majority of sand and gravel came from the town of Needham to the west of Boston. The source were kame terraces and eskers - fluvioglacial depositional structures deposited during stagnation or retreat of the Laurentide continental ice sheet. "Steam-powered excavators" loaded two shovel-fills per car (a six-ton load) onto a gravel train of some 35 cars in length - a 35 minute-job! Needham's loss was Back Bay's gain as fifty foot-high hills were "transformed to a desert." They worked day and night as 145 gravel cars and 80 men made 25 trips per day - loading, transporting and dumping onto the shores of Great Bay's Receiving Basin.
The railroads that entered Boston in the 1830's provided an inexpensive long-distant means of transporting massive amounts of sand and gravel to the Receiving Basin, although additional spurs had to be added and locomotives, side-dumping gravel cars and steam shovels had to be financed and purchased. The trains made the nine-mile, 45-minute trip to Back Bay by initially taking a spur to the New York and Boston mainline (Penn Central tracks), then to the Green Line's Riverside Branch in Newton, and finally the lines of the Boston and Worcester Railroad (the commuter rail along the Mass Pike) from Brookline to Boston.
|A Steam-powered Locomotive and Gravel Train Makes its Way Through the Town of Newton|
Jackson Homestead Archival Photograph Collection
Filling Back Bay began in 1858 at the edge of the Public Garden. The defunct Mill Dam provided the retaining structure for the fill. Railroad spurs were continually revised to facilitate dumping further and further outward over the mudflats in the directive of the Mill Dam. Four separate areas of Back Bay were simultaneously filled to speed up the process, while progressing from east to west toward the cross dam.
Dumping specifications required that sand and gravel be built up over the mudflats so that the elevation of streets were 18 feet above mean low tide called the Boston City Base, which was the level of the Mill Dam, while house lots were filled six feet lower to conserve the transportation of material where basements would be located. Although particular attention was given to concerns over the water table, problems exist across Back Bay's modern landscape related to fluctuating groundwater levels and flooding. Leaks in train and subway tunnels, highway underpasses, basements, sewers and drains lower the water table forcing cracks to occur in foundations and exposing wood pilings to rot and subsequent collapse.
Horse-drawn graders then contoured the landscape for streets under construction. Wood pilings were driven through the cover of land fill and underlying mud to hard, marine clay, which was typically 30 to 40 feet below ground surface. As long as they remained submerged in groundwater, they would last for centuries. If groundwater dropped, the pilings would become exposed to air, attacked by microbes, eventually rot and collapse causing severe foundation problems. The potential problem isn't solely Back Bay's but wherever land was "made" in Boston - the Fenway, South End, Bay Village, Beacon Hill Flat, Chinatown, Leather District, Bulfinch Triangle, North End, Downtown waterfronts, Fort Point Channel section of South Boston and parts of East Boston. Observation wells at various locations monitor water levels. (Read about it here).
Buildings were erected starting from Arlington Street at the Public Garden as filling was progressing to the west. The process progressed westward when Massachusetts Avenue was reached in 1870. In time, sand and gravel was obtained from other sources such as Hyde Park, Canton and Dedham to the southwest of Boston. In 1865, the sluiceways of the mills were filled in, a major milestone in the filling of Back Bay. Ultimately, the area to the west that included the Muddy River, a tributary of the Charles, resulted in the creation of the freshwater Back Bay Fens - another link in Olmsted's Emerald Necklace.
BACK BAY TAKES SHAPE
The meticulous planning of Back Bay was realized when construction for residential buildings was initiated as "well to do" families began to move in, even as landfill was progressing just to the west. A conscious effort was made to insure upper middle-class residential occupancy by prohibiting the presence of mechanical, mercantile or manufacturing. Height restrictions, setbacks, facades, number of stories and service alleys at the rear of residential buildings were mandated as well. Even lot sales to the "right sort" were carefully controlled.
It was apparent that Back Bay would become the antithesis of colonial Boston - "new", flat, clean, orderly, systematic, spacious and well-planned - the result of a multitude of land reclamation projects that were conducted governmentally, corporately and individually. Even east-to-west streets were assigned alphabetical names that alternated di- and tri-syllabically. Beginning with Arlington Street along the western edge of the Public Garden, it's followed by Berkeley, Clarendon, Dartmouth and so on. At Back Bay's western boundary at Charlesgate, where the tributary of Muddy River enters the Charles, the naming convention continues with Ipswich, Jersey and Kilmarnock Streets.
The architectural design that was employed was systematic as well, although not plan-specified. As filling in proceeded from east to west, construction progressed accordingly and reflected the popular architectural design and building stone - mansard-roofed French Academic, Gothic, Ruskinian Gothic (High Victorian Gothic), Queen Anne and Panel Brick, along with many revival styles such as Italian Renaissance, German Renaissance, Beaux Arts, Chateauesque, Georgian, Federal and Adamesque.
Boston's proximity to several sources of stone encouraged its incorporation into the construction of Back Bay's buildings. Thirty-six early churches had foundations of Late Proterozoic Roxbury Conglomerate ("puddingstone"). Facings progressively included Portland and Longmeadow Jurassic sandstones ("Brownstones") from the Connecticut Valley and Newark Basin in New Jersey. Common brick was fired from Holocene Boston Blue Clay. Paleozoic granites came from Dedham, Quincy, Chelmsford, Westerly Rhode Island, and the Maine coast, and later Indiana Limestone and Vermont marble arrived by rail.
LOOKING BACK OVER 400 YEARS OF URBAN EVOLUTION
Back Bay had become the elegant and fashionable neighborhood that had been envisioned. But its evolutionary journey was far from complete once the embayment was filled in and the neighborhood became occupied. In the early twentieth century, the last filling in (east of Massachusetts Avenue) includes the narrow park of the Boston Embankment along the Charles River, later widened to form the Esplanade in the 1930's and the addition of the Storrow Drive highway along the river in 1950.
Here's a look back at Greater Boston in 1873. Present day Boston bears little resemblance to the peninsula that jutted out into the harbor some 400 years earlier.
Tucked into the northwest corner of the Public Garden at the corner of Arlington and Beacon Streets is a dramatic and powerful bronze statue by Daniel Chester French completed and dedicated in 1924. It's entitled "Casting Bread Upon the Waters" from Ecclesiastes 11:1. Entirely meant for a different message, the angel is ironically casting bread upon what was once the tidal waters of the Mill Dam's Receiving Basin.
|"Cast They Bread Upon The Waters For Thou Shalt Find It After Many Days"|
MAPS OF BOSTON ONLINE
• Boston Athenaeum (here).
• David Rumsey Map Collection (here).
• Digital Commons at Salem State University (here).
• Norman B. Leventhal Map Center at the Boston Public Library (here).
• Avalonian Perspectives on Neoproterozoic Paleogeography: Evidence from Sm-Nd Isotope Geochemistry and Detrital Zircon Geochronology in SE New England, USA by M.D. Thompson et al, GSA Bulletin, 2011.
• Boston - A Topographical History by Walter Muir Whitehill and Lawrence W. Kennedy, The Belknapp Press of Harvard University Press, 2000.
• Boston's Back Bay - the Story of America's Greatest Nineteenth-Century Landfill Project by William A. Newman and Wilfred E. Holton, Northeastern University Press, Boston, 2006.
• Cobblestones, Puddingstone and More: Boston's Use of Stone as an Essential Urban Element - A Walking Tour by Dorothy Richter and Gene Simmons, Guidebook for Geological Field Trips in New England, 2001 Annual Meeting of the GSA, Boston, Massachusetts.
• Digging up Boston: The Big Dig Builds on Centuries of Geological Engineering by Bradford A. Miller, Geotimes, American Geosciences Institute, October 2002.
• Gaining Ground - A History of Landmaking in Boston by Nancy S. Seasholes, The MIT Press, 2003. Encyclopedic in content with great maps and images!
• Houses of Boston's Back Bay: An Architectural History, 1840-1917 by Bainbridge Bunting, 1967.
• Reinventing Boston: 1630-2003 by Edward L. Glaeser, Journal of Economic Geography 5, 2005.
• Sedimentology of the Squantum 'Tillite', Boston Basin, USA: Modern Analogues and Implications for the Paleoclimate During the Gaskiers Glaciation (c. 580 Ma) by Shannon Leigh Carto, Thesis, Graduate Department of Geology, University of Toronto, 2011.
• The Application of Geographic Information Technology and Ground-Penetrating Radar in the Study of the Evolution of the Charles River Basin by Lars E. Anderas, Masters of Science Thesis, University of Massachusetts Boston, 2013.
• The Geology and Early History of the Boston Area of Massachusetts, A Bicentennial Approach by Clifford A. Kaye, U.S. Department of the Interior, Geological Survey Bulletin 1476.
• Urban Geology of Back Bay and Beacon Hill, Boston, Massachusetts by James W. Skehan et al, Guidebook for Geological Field Trips in New England, 2001 Annual Meeting of the GSA, Boston, Massachusetts.