Pre-Handout
Scope and Background
This design project is a large scale planning project and as such it is open ended. Its complexity requires that the design is done by a team. You should follow the design process as given to you in the lectures.
The intent of this project is to have you define the constraints as part of the problem formulation. While it may be unusual to have such a "wide open" project it is a good way to start with any planning or design project to assume very relaxed boundary conditions. This will give you the freedom to come up with innovative solutions even when you add constraints.
In this particular exercise you will not only have the opportunity to plan and design a different "Back Bay" but you will be able to compare what was actually done with what one (you!!) could have done.
Imagine Boston in the topographical shape of the late 18th century!
When the first settlers founded Boston, its topography looked much different from what it looks now. At that time Boston was a pear-shaped peninsula, which was connected to the mainland only through a narrow neck.
The peninsula was bordered by large tidal flats and had many inlets and coves. One of these, North cove, was cut off by a mill dam/causeway already in 1640. On a small scale the shoreline had been changed more or less permanently from that time onwards. However, changes on a larger scale did not occur until the beginning of the 19th century.
Design Task
You are charged with the development of the Back Bay area based on the topography as it existed around 1800, but using modern construction technology and satisfying present day requirements. You have to create a mixed residential-commercial area with 50,000 inhabitants. You are completely free in your choice of buildings, access (transportation), providing foundations a.s.o. You are strongly encouraged to propose non-traditional solutions.
The result of your work should be in form of a rough plan indicating residential/commercial zones, major streets or other access. In an accompanying report (max 4 pages, double-spaced) you should explain how your design satisfies the boundary conditions and present concepts of how you address major technical, aesthetic and environmental issues. One technical and/or environmental problem should be analyzed more thoroughly. You should also indicate if what you propose will end up with medium or with high costs. More specific comments on the deliverables are given below.
Topography, Design Area
The Charles River is a tidal basin with the tides varying between el. 100.8ft (mean low water level) and el. 110.2ft (mean high water level). The highest reported tide occurred in 1851 with el. 116.6ft. The elevation of the adjacent land is approximately 117 feet. As mentioned above, part of the Charles River bottom is exposed during low tide, forming so-called tidal flats. Conversely, during high tides the water level in Boston Harbor may be such to cause considerable backflow into the Charles River. If this occurs in conjunction with major rainfall and large flows in the Charles River, the shore areas can be flooded.
The design area is Back Bay, which is bordered by today's Massachusetts Ave., Storrow Dr. and the original shoreline of the Boston peninsula.
The buildings and streets on the original peninsula are the way they are at present. Assume that there are no railway lines and no T-lines existing in the design area.
Geology, Rules of Thumb for Foundations
A typical soil profile of the present Back Bay is shown in Figure 1. One-story buildings can be placed directly on the fill without basement, 3-5 story buildings can be placed on the fill with a 1 story basement, higher buildings require correspondingly more basements. High rises up to 15 stories can be put on piles reaching into the till; higher buildings have to be put on piles reaching the bedrock. Clearly deeper foundations cause higher costs. (Note: There was no fill when the original Back Bay existed)
As indicated earlier, you should work with the most modern construction technology and materials. If you want to fill the area with soil before building, you can either use gravel from gravel pits in the Needham area or from dredging in the Charles River next to Back Bay. (You need to think about the consequences using these material resources, however.)
Protection from High Tides
One of the options you may consider is to close off the Charles River from Boston Harbor. Keep in mind, however, that what you propose will have some environmental impacts, which you have to address.
Several cities have installed facilities to protect themselves from high tides. Here are some examples:
- London: The Thames barriers are open during normal operation but close during surge tides. (see Flood London).
- Venice: To protect the lagoon from high tides a new barrier system is proposed (see the Mobile Flood Barriers).
Deliverables
- Land use plan with transportation network, building type both re use and height, and other land usage
- Report with figures (the figures are in addition to the 4 page text) describing:
- Land use reasoning
- Concept re major technical issues (e.g. foundations, structures, transportation, utilities)
- Concept to handle tidal problems and other environmental issues that may arise
- More detailed discussion of one technical/environmental problem (without going into more than rule-of-thumb calculations)