PART V_Pittsburgh Main Thoroughfares and the Down Town District Improvements Necessary to Meet the City's Present and Future Needs

_Special Reports_

THE MARKET

Two conclusive reasons point to the removal of the Diamond Square

Market from its present site. First, it is an obstruction at a vital

point to the development of the thoroughfare system of the city;

second, it is too small and congested for the proper performance of its

functions.

The ingenious proposition has been made, in order to secure more space

for the business, that the whole of the square be excavated and a

basement or underground market be built extending under the surrounding

streets. This would permit the extension and widening of Diamond Street

and Market Street through the square at the ground level, although

these improvements were not contemplated by those who suggested the

basement market. Such an arrangement, if not coupled with the erection

of structures above ground in such a manner as to interfere with the

free passage of the two streets through the space, would seem to meet

the traffic problem; except that the massing of vehicles and people

on the surface, in connection with the marketing, would be somewhat

objectionable.

But from the market point of view such a solution seems wholly

unsatisfactory and inadequate. There is no question that the space is

now too small for handling the business in a comfortable, sanitary

and decent manner, and the space now occupied is by no means confined

to the two old buildings. The sidewalk stalls, so called, from which

nearly half the rentals of the market are derived, occupy a large

part of the surrounding streets, and at the busy hour there is hardly

a square foot of those streets that is not in use by the dealers or

their customers. To build a basement market occupying the whole of the

square, after deducting the considerable space required for entrances,

stairways or inclines, elevators, piers, ventilating shafts, etc.,

would not materially enlarge upon the present facilities; and it

would put the market in a position where automatic means of relief, by

overflow into the streets and into adjacent private stores, would be

practically impossible. Moreover, the opinions of market-men and of

experts on the values of retail trade locations seem to be that the

chances are desperately against the commercial success of any basement

or underground market, no matter what skill may be exercised in meeting

the problems of lighting, ventilation, and means of access.

In judging other possible solutions of this very perplexing problem it

is important to consider the experiences of other large cities of the

northeast states with the market business.

With only two exceptions all the markets of Boston, New York,

Philadelphia, Baltimore and Washington have become less and less

profitable during recent years. In some cases the business has fallen

off so much that half the stalls are vacant, and in others the markets

have had to be abandoned. The reasons offered by market superintendents

and others for this general decline, upon analysis, may be summarized

as follows: (1) With the increase in size of cities and the general

change in habits, retail purchasers find it increasingly troublesome to

go to a central market, and attach an importance to the convenience of

purchasing from neighboring local provision dealers, and of having the

goods delivered. (2) Owing also to general changes in habits of life,

especially to the increasing specialization of knowledge and skill of

all kinds, the average retail purchaser is becoming constantly less

competent to form an independent judgment of the quality of provisions

offered for sale, is more conscious of this incompetency, and is more

and more dependent upon the reliability of the dealer; he is therefore

less able to get any advantage from purchasing in an open competitive

market. This again obviously makes for the advantage of the local

provision stores. An index of this tendency is the increasing amount of

ordering by telephone and otherwise "sight unseen."

Both the above factors, but especially the latter, are reflected in the

fact that such of the public markets as are falling off least in their

business are taking on more of the character of wholesale markets where

the purchasers are experts representing either local retail provision

dealers, or hotels, clubs and restaurants.

The two markets which have proved exceptions to the general rule are

the Reading Terminal Market in Philadelphia and the Center Market

in Washington. The Reading Terminal Market is owned by the Reading

Railroad and is managed by a superintendent who has absolute control.

It has been built up from nothing, fifteen or twenty years ago, to

a flourishing business at present, and this has all happened in the

face of the general decline in the market business throughout this

section of the country. Mr. McKay, the superintendent, attributes his

success to three main causes. In the first place, every consideration

possible is given to the farmers; stalls are rented to them at about

one-third the prices paid by city dealers and they are never ousted in

favor of the latter. Furthermore, Mr. McKay spends considerable time

canvassing the agricultural sections of the country within fifty miles

of Philadelphia, hobnobbing with the farmers, getting them interested

in selling their produce to the best advantage through facilities which

he can offer them. In fact he does everything possible to encourage the

farmers to make use of the market both for their own advantage and for

his. In the second place, direct railroad connections furnish the best

possible transportation facilities. Produce can be collected from the

surrounding country at the least possible cost, and can be delivered to

suburban residences much cheaper than by independent city stores. The

third reason for success is able management. The market business, like

any other, needs able management, and without that it is probable that

any market undertaking, no matter how favored in other circumstances,

will run a large risk of financial failure.

The success of the Center Market in Washington is apparently due mainly

to the close relation maintained with the farmers and to its efficient

general management.

It may be noted further that in Germany practically all the large

public market houses have direct railroad connections.

In Pittsburgh the market business is apparently flourishing; and

this in spite of the facts that no special encouragement is given to

the farmers, that there are no direct or convenient transportation

facilities, and that the management is not especially able. Considering

the experiences of other cities, it is hard to account for this

condition, but it is only reasonable to take warning and to expect a

decline in the business sooner or later unless radical improvements are

made.

It is to be considered furthermore that the city is not in the market

business simply for the sake of getting a little revenue out of it.

It is justified in conducting such an enterprise only on the ground

that it provides a facility for the people which can not otherwise be

well and economically provided. In the first instance public market

places have always been established as a convenient means of purchasing

provisions in an "open market," a place where prices are supposed to

be determined by free competition among the producers with the minimum

absorption of profit by the agencies roughly indicated by the term

"middlemen." Under modern conditions, as the gap between the producer

and the consumer has grown steadily bigger, the mere providing of

a convenient vacant space in the city, where producer and consumer

could meet and do their bargaining, has proved utterly insufficient.

Apparently the recognition of the changing conditions has been so tardy

on the part of those representing our cities in the administration of

public markets, and their action so timid and temporizing, that they

have left the bridging of the gap to commercial middlemen. In the

course of the last two or three generations, therefore, the public

provision markets have become largely places for a special group of

middlemen, or retailers, to display their wares; in essence not very

different from the natural groupings of other classes of retailers'

stores in various quarters of the business district.

It is, therefore, of peculiar interest to note that the only two public

markets in the cities investigated which have not shown a decline of

business are those in which _special, constructive efforts_ have been

made, by the market administration, to maintain a close relation with

the producer and to minimize the growing obstacles that tend to impede

and complicate and make costly the operation of transferring goods from

him to the consumer. Not only do these two exceptional markets with

increasing trade point this moral very clearly; but at Boston, where

the market is still very successful, though in diminishing degree and

with an increasing emphasis on the wholesale end of the business, the

superintendent is very clear in his view that it is upon the facilities

offered to the farmers for direct sale from their wagons that the

continued success of the market largely depends.

It is one of the unfortunate features of the Diamond Square Market

that it has been thought necessary to segregate the farmers' wagons in

another locality, and a serious objection to the Square as a permanent

market site is the impossibility of providing for them in connection

with it. But while the farmers' wagons are important, even more

important is the maintenance of facilities for the economical shipment,

receipt, and sale of provisions from farmers who cannot bring their

goods to market in their own wagons. Pittsburgh is not in the midst

of an ideal farming country and an exceptionally large proportion of

its food must come by rail. Even in Philadelphia, where the immediate

surroundings of the city are much better adapted for the raising of

provisions, the notable success of the Reading Market is largely due

to the economical and convenient arrangements for getting produce to

market by rail, and in Pittsburgh such facilities seem almost essential

to any large and permanent success.

It seems clear then, that, if such a permanent success is to be made

of the Pittsburgh Market, it must be moved from Diamond Square to a

larger site with rail connections and room for farmers' wagons. Several

localities have been studied with this idea in view and the best of

them appears to be, as recommended earlier in this report, between

Third and Fourth Streets and Penn and Liberty Avenues. The advantages

of the site briefly are as follows: First, it is not far from Diamond

Square, and is even more accessible from the cars passing over the

Point Bridge by which a large proportion of the present patrons of the

Market appear to arrive; and furthermore, the improvement of street

railway transportation will undoubtedly mean the through-routing of

cars, a change which will make this site directly accessible also

from other sections of the city. Under the circumstances, to move

the market so short a distance should not involve any serious loss

of trade. Second, the land and the buildings are reasonably cheap

although the frontage is on Liberty Avenue, one of the main arteries

of travel in the Point District. Third, the area is large enough to

allow a reasonable provision of space where farmers can remain and sell

produce directly from their wagons and not be forced, as at present, to

do business at a distance, on the Monongahela wharf; and furthermore

there is plenty of room for expansion either across Penn Avenue or

Fourth Street. Lastly, in this location, a direct connection already

exists, via the Duquesne Elevated, with the Pennsylvania Railroad

System, the most important freight carrier in the District; also the

site is close to the Wabash Railroad, with which connection could be

secured if further developments of the road should justify it; and

being close to the Allegheny River all possible advantage can be taken

of river transportation, especially for the receipt of produce.

It should be noted further that even with the best advantages of

site and physical equipment a public market is by no means sure of

success. More important probably than any other one element making for

success is able and stable management. The market business is a large,

intricate and many-sided business; and it is not reasonable to expect

any very brilliant results under the management of a succession of

superintendents rotating in office with political changes in the City

Government, and not selected because of any special qualifications of

experience or great business ability. A highly competent superintendent

holding his office during good behavior will be essential to the

success of the new market in Pittsburgh.

THE HUMP CUT

The purpose of this improvement, upon the successful attainment of

which the plans must be judged, appears to be twofold: (1) To reduce

the obstacle offered by the Hump to the general street traffic of the

city, and (2) to reduce the obstacle which appears to be offered by

the steep gradients to the expansion of the district available for

high-class retail trade and offices.

The former is the larger consideration as regards the whole city. The

latter is the main consideration as regards the locality itself and the

interests of the owners of land therein.

The plan of the Bureau of Surveys, marked "Approved December 23, 1909,"

shows proposed gradients on the east and west streets ranging from 4.75

per cent on Sixth Avenue to 5.88 per cent on Diamond Street, Fifth

Avenue being 5.52 per cent. On Grant Street the maximum gradient is

proposed to be reduced from 4.8 per cent to 4.6 per cent. While these

proposed gradients are undesirably heavy, it is believed that they

would not in themselves offer a very serious obstacle to the advance

of first-class business into the Hump District if for other reasons

the growth should tend in that direction. Further, for automobiles,

electric cars and light horse-drawn carriages the proposed gradients,

while objectionable, are not, in view of the topography of Pittsburgh,

very excessive. Such gradients, however, are prohibitive to economical

teaming. They will be avoided by teamsters at the expense of a long

detour if they can find a route of low gradient, and if there is no

such route they mean the hauling of smaller loads, the making of more

trips to do the same work, and a very appreciable tax upon the public,

paid in the cost of coal, building material, household supplies, etc.

Almost at first sight there appear two important lines of travel

which might naturally be expected to pass through the Hump District,

and which would be seriously affected by gradients as heavy as those

remaining under the Bureau of Surveys' plan. One is that leading from

the Point District and from practically all the freight yards into

the valley occupied by Fifth Avenue and Forbes Street. A second line

which may be expected to have great importance is one connecting

Second Avenue east of Try Street with Liberty and Penn Avenues in the

vicinity of the Union Station--in other words, the most easterly line

upon which a connection of easy gradient can be secured between the

two valleys. The improvement of Forbes Street as the main artery of a

large eastbound thoroughfare system, the location of the traffic artery

to the South Hills region--the high-level bridge and tunnel--and the

location of the proposed Municipal Building and Civic Center, which

are all recommended in Parts I and II of this report, must inevitably

add greatly to the importance of this region behind the Hump as a

distributing point for traffic. Sixth Avenue, especially the diagonal

portion, Fifth Avenue and Diamond Street are the thoroughfare lines to

this point. Considered together with other improvements of the down

town district, Diamond Street becomes perhaps the most important line

over the Hump. From the point of view of the city as a whole, any plan

for cutting the Hump which does not secure reasonable gradients on

these thoroughfares must be regarded as ineffective.

[Illustration: PLAN FOR THE PROPOSED HUMP CUT]

[Illustration: PROFILES OF THE PROPOSED HUMP CUT]

The accompanying plan and profiles indicate the area and amount of cut

which appears to be the least that should be undertaken. The area is

practically the same as that proposed on the Bureau of Surveys' plan

of December, 1909; the cut at certain places, however, is considerably

deeper. A cut of 11.3 feet at Grant and Diamond Streets gives a maximum

gradient of 4.75 per cent on the latter; a cut of 14.3 feet at Grant

Street and Fifth Avenue gives a maximum gradient of 4.74 per cent on

Fifth Avenue; and a cut of 8.9 feet at Webster and Sixth Avenues gives

a maximum gradient of 4.34 per cent on the latter and 3.4 per cent

on the Grant Street-Sixth Avenue cross-town route. These gradients

are certainly not ideal, but it is believed that they are good enough

to justify the undertaking, and deeper cuts are not urged chiefly

because the area of cut would thereby be extended further into abutting

regions where little or no benefit could be assessed and practically

no damage-waivers could be obtained; the cost of the undertaking being

thereby inordinately increased.

On Grant and Ross Streets the maximum gradients proposed are about

4.5 per cent, not excessive for lines which are not of the first

importance. There is little advantage in extending the cutting any

further on Wylie Avenue than is forced by the cut on Sixth Avenue, for

there is no object in securing an easy gradient at one point when the

gradient just beyond is over 7 per cent and cannot well be improved.

The same applies to Webster Avenue east of Tunnel Street, but it must

be cut heavily at this point partly on account of the cut at Sixth

Avenue and partly to provide a good gradient on the extension of Grant

Boulevard.

The extension of Grant Boulevard and the widening of Webster Avenue

from Tunnel Street to Grant Street, the widening of Strawberry Way

and Oliver Avenue and the widening of Sixth Avenue and Diamond Street

have been recommended in the first part of this report. It is further

recommended: (1) that Fifth Avenue between Ross and Grant Streets be

widened to 60 feet; (2) that Cherry Alley be widened to 50 feet between

Fifth Avenue and Sixth Avenue, and (3) that the westerly corner of

Sixth Avenue and Grant Street be cut off enough to allow the passage of

one line of vehicles between the curb and a car rounding the corner.

These changes should all be incorporated in any general plan for

cutting and improving the Hump District.

THE CITY AND THE ALLEGHENY RIVER BRIDGES

_Recommendations for Bridge Heights and Pier Location to Meet the

Various Transportation Needs of Pittsburgh_

BY COLONEL THOMAS W. SYMONS AND FREDERICK LAW OLMSTED

INTRODUCTION

March 15th, 1910, upon recommendation of the Committee on City

Planning, the Pittsburgh Civic Commission authorized Colonel Thomas

W. Symons, Corps Engineers, U. S. A. retired, and Mr. Frederick Law

Olmsted to make a report upon desirable heights and pier locations for

bridges over the Allegheny River. The purpose of the Commission was

to secure a report which weighed the interests of all parties to the

bridge question, and which would strike a balance to meet the various

transportation needs of Pittsburgh.

The Commission asked the Committee on City Planning to direct the

preparation of the report. The Committee consists of T. E. Billquist,

chairman; Charles F. Chubb, H. J. Heinz, Benno Janssen, Richard

Kiehnel, E. K. Morse. This committee passed upon the report April

18th and recommended it to the Commission for adoption. On April

25th the Commission received and adopted the report and voted their

hearty appreciation of the work of Colonel Symons, Mr. Olmsted and the

Committee on City Planning. This report was published separately in May

1910.

RECOMMENDATIONS

1. That the Sixteenth Street and Forty-third Street bridges, which are

obstructions to navigation on account of their pier locations, narrow

channels, and exceptionally low clearance height, be required to be

rebuilt with their piers so located as to give channels conforming to

the neighboring bridges, and that their elevation be fixed with regard

to eliminating the railroad grade crossings on their approaches, but

the minimum clearance shall be fixed in accordance with the closing

paragraph below.

2. That the Ninth Street bridge should be rebuilt as soon as

practicable with a central pier and two wide spans conforming to those

of the Sixth Street and Seventh Street bridges. The design of the new

Ninth Street bridge, however, should not be finally determined and

erection begun until a definite plan for comprehensive improvements in

the traction system between the two sides of the river has been decided

upon. Unless new circumstances develop before the construction of this

bridge is begun that materially affect the problem of clearance height,

the elevation should be fixed in accordance with the closing paragraph

below.

3. That all questions pertaining to changing the elevation of the Sixth

Street, Seventh Street, Fort Wayne, Thirtieth Street and Junction

Railroad bridges be deferred to await the report of the Pittsburgh

Flood Commission and the resultant action; to await the report on a

comprehensive plan for traction improvements; to await the completion

of the work projected by the City in cutting down some streets and

filling others; and to await the results of the investigation of river

boat design and construction provided for in the River and Harbor bill

just passed by Congress.

4. That if it is deemed essential and necessary at present to decide

upon the elevation to which all Allegheny River bridges must be made to

conform, this elevation be fixed so that there shall be a clear head

room of substantially 37 feet above pool level, varied so as to give

at each bridge a clear head room of 28 feet when the river is at a 15

foot flood stage. This height to be maintained over the entire main

span where there is a central span and for 180 feet on each side of the

central pier where there is a central pier.

FULL REPORT

April 19th, 1910

THE PITTSBURGH CIVIC COMMISSION:

_Gentlemen_: In accordance with your expressed desire we have examined

into the bridge problem on the Allegheny River now before the City,

particularly in regard to the use of the bridges and their connections

with the streets of the city and the use of the river for harbor and

navigation purposes, and beg to submit the following report thereon:

[Illustration: German side-wheel boat, common on European rivers]

There are three great interests concerned in the problem of the bridges

over the Allegheny River at Pittsburgh: (1) those who frequently cross

the river or whose business requires the transportation of workmen,

raw and manufactured material, and supplies from one side of the river

to the other; (2) those concerned in the navigation of the river and

harbor, and (3) those who own and operate the bridges.

In the hearings recently held on the subject much consideration has

been given to the bridge owners and the navigation interests but

comparatively little attention has been given, at first hand, to the

interests of the general public, who in great numbers are interested in

transportation across the river and for whose service both the bridges

and river transportation exist.

[Illustration: Design of boat for American rivers, adapted from

European models]

It is quite apparent, from a study of the situation and the interests

involved, that changes might be demanded in the bridges which would

give some added advantage to river navigation, but yet would place so

great a burden upon the interests concerned in crossing the river that

the result would be a net loss to the general public. The following are

the two extreme positions somewhere between which all concerned would

agree that a balance of interests most beneficial to the general public

must be determined:

[Illustration: Wharf at Cologne, showing heights of boats]

From the viewpoint of traffic across the river the best arrangement

would be level bridges at the grade of the connecting streets,

regardless of river traffic. The more bridges are raised above that

standard, apart from any question of first cost, the greater will be

the interference with travel across the river, up to the point of

prohibitive grades on the bridges and their approaches. Before this

point is reached drawbridges must be considered which, while often

required and adopted, are objectionable to the interests using the

bridges and those passing under or through the bridges.

From the viewpoint of the river interests the most complete improvement

would be to do away with the bridges entirely, thus giving absolute

freedom of navigation. This is out of the question. The next best thing

from that point of view would be to change the bridges to one span

each across the river from bank to bank with height enough for passage

beneath of the highest floating structures at all stages of the river.

This would be impracticable without remodeling the city along both

sides of the river for long distances from the banks at an expense so

great as to be almost beyond computation. Anything less than this will

impose, at least in theory, some hindrance upon river navigation, and

this hindrance will be greater in amount as the head room is decreased

and as piers are introduced into the river.

The aim in arriving at a solution of the bridge problem must be to

adjust these conflicting interests impartially; and the factors to be

considered in arriving at such an adjustment are these: _First_, the

amount and importance of the traffic likely to be affected in each

case. _Second_, the extent to which any given solution would benefit or

injure the bridge traffic and the river traffic, respectively.

1. _Amount and Importance of Traffic Affected._--_(a)_ _Bridge

Traffic_.--There are in question six highway bridges and two railroad

bridges.

UNDER BRIDGES OVER BRIDGES

--+---------+---------------+----------+------------------------------------

TONNAGE IN MILLIONS

██|2,344,398| SIXTH ST. |13,240,010|████████

██|2,796,122| NINTH ST. |14,732,130|█████████

█|2,228,270| FT. WAYNE. |53,127,210|████████████████████████████████████

▐|1,045,570| THIRTIETH ST. | 398,430|▎

▐| 865,024| JUNCTION RR. |24,335,982|████████████████▌

▐| 714,856|FORTY-THIRD ST.| 311,090|▎

--+---------+---------------+----------+------------------------------------

PASSENGERS IN MILLIONS

▕| 25,680| SIXTH ST. |27,098,291|████████████████████████████████████

▕| 30,567| NINTH ST. |24,325,900|████████████████████████████████▌

▕| 24,408| FT. WAYNE. | 4,877,495|██████▌

▕| 11,455| THIRTIETH ST. | 715,985|█

▕| 9,475| JUNCTION RR. | 217,254|▎

▕| 7,831|FORTY-THIRD ST.| 816,333|█

--+---------+---------------+----------+------------------------------------

UNDER BRIDGES OVER BRIDGES

Diagram No. 1, showing comparative importance of traffic over and

under Allegheny river bridges

+------------------------------------------------------------------+

| +----------------------------------------+ |

| | | |

| | 108,000,000 TONS | |

| | | |

| +----------------------------------------+ |

| OVER BRIDGES |

| |

| +----+ |

| | | |

| +----+ |

| 1,500,000 |

| TONS |

| UNDER |

| BRIDGES |

| |

| COMPARATIVE DIAGRAM SHOWING TOTAL TONNAGE, OVER AND UNDER THE |

| ALLEGHENY RIVER BRIDGES. |

| |

| TO ACCOMPANY REPORT OF |

| COL. THOMAS W. SYMONS. |

| FREDERICK LAW OLMSTED. |

+------------------------------------------------------------------+

Before referring to the statistics in regard to traffic over these

bridges we wish to point out that much the greater part of it is of a

kind daily and intimately affecting the business and the convenience

of a large population. Any delay affecting the transportation of

passengers over any of these bridges, and any delay or any increase of

cost in teaming package freight and supplies from freight stations and

warehouses and stores on one side of the river to their destination on

the other side, would be felt very sharply by a considerable fraction

of the manufacturers, merchants and other citizens of Pittsburgh. The

inconvenience arising from any interference with traffic of this class

would clearly be greater in proportion to the volume and value of

the traffic than in the case of the slower moving river traffic. Ten

minutes' delay to people in reaching their offices or an hour's delay

beyond the expected time in the delivering of household food supplies

or express packages, etc., for a number of families, is a much more

serious matter than a corresponding or even a greater delay in the

delivery of a barge-load of gravel or coal, even though the barge-load

were of equal value with the delayed lot of supplies.

Details in regard to the volume of traffic over the bridges and

estimates of the value of the goods transported and the equipment

engaged in the traffic are given in Appendix I and are summarized in

graphical form in Diagrams 1, 2 and 3. The amount and importance of

bridge traffic may be summarized by stating that there passes over the

existing Allegheny River bridges each year about 108,000,000 tons of

traffic roughly valued at $9,350,000,000; and about 62,700,000 human

beings, passengers and pedestrians.

+------------------------------------------------------------------+

| +---------------------------------------------+ |

| | | |

| | $9,366,973,935 | |

| | | |

| +---------------------------------------------+ |

| OVER BRIDGES |

| |

| +----+ |

| | | |

| +----+ |

| $105,000,000 |

| UNDER |

| BRIDGES |

| |

| COMPARATIVE DIAGRAM SHOWING TOTAL VALUE OF TRAFFIC OVER AND |

| UNDER THE ALLEGHENY RIVER BRIDGES. |

| |

| TO ACCOMPANY REPORT OF |

| COL. THOMAS W. SYMONS. |

| FREDERICK LAW OLMSTED. |

+------------------------------------------------------------------+

_(b)_ _River Traffic._--The data in regard to existing navigation

under the Allegheny bridges consist of detailed reports of vessels

and cargoes passing Dam No. 1 and counts of the number of vessels

passing under the several bridges during representative periods of

from one to two months in 1909. From these data we have estimated the

annual river traffic under each of the bridges, and very roughly, its

value.[32] These amounts are shown graphically in comparison with the

corresponding figures for traffic over the bridges in Diagrams 1, 2 and

3. To briefly summarize, it may be stated that the river traffic of the

Allegheny River in one year amounts in the aggregate to about 3,500,000

tons, including all freight carriers and power boats, roughly valued at

about $105,000,000; and about 35,000 human beings, passengers by boat.

It seems well here to note that the water-borne traffic of the

Allegheny River has been steadily decreasing for many years and is now

but a small portion of that which once existed. That this decline in

river traffic is not due to the interference of the bridges is shown

by the statement that the navigation facilities are better than ever

before. It is due to the lack of modern terminal facilities, boats and

methods of carrying on business.

There is a possibility that, in case improved conditions are provided

for Allegheny River navigation, the amount thereof may increase with

the lapse of years, but for the reasons set forth in Appendix II,

this increase is not likely to be so great in relation to the natural

increase of the bridge traffic as to render the comparison of the

existing facts in Diagrams 1, 2 and 3 inapplicable to the future.

_(c)_ _Comparison of Bridge and River Traffic_.--To sum up, it may be

said that each year the amount of traffic passing over the bridges is

at least 30 times that floating on the water of the river, and about 90

times its value. The passenger traffic over the bridges is about 1800

times that on the water. The character of the traffic over the bridges

is such that a given degree of interference with it is a far more

serious annoyance to the public than the same degree of interference

with river traffic.

[Illustration: Paris passenger and freight boats]

2. _Effect of Various Solutions._--It remains to be considered to what

degree the bridge traffic and the river traffic would be hampered or

facilitated by various permanent solutions of the bridge problem. With

a view to arriving at a plan as nearly ideal as the circumstances

permit for a permanent arrangement of bridges over the Allegheny

River, various projects have been put forward and considered. These

concern two nearly independent matters, the elevation of the bridges

above pool level and the location and design of the bridge piers. The

former must be decided with regard to the effect upon both bridge and

river traffic; the latter may be determined with regard solely to the

navigation interests, giving due consideration to the cost and the

appearance of the resulting bridges, as discussed below.

[Illustration: Barge and towboat designed for shallow rivers and low

bridges in the United States]

The plan upon which interest is now most centered is that officially

recommended by the local office of the United States Engineer Corps. We

shall consider the effect of the bridge heights proposed in this plan

as compared with certain modifications thereof; first, upon the bridge

traffic, and second, upon the river traffic.

_(a)_ _Effect of Various Possible Bridge Heights upon the Traffic

over the Bridges_.--_Highway Bridges._--The highway bridges carry two

principal classes of travel. The first consists of vehicles moved by

power, electric cars and automobiles, and of pedestrians. With this

class an increase of gradient on the bridges or their approaches,

within reasonable limits, simply means the expenditure of a moderate

amount of additional energy without material loss of time, or other

difficulties. The second class consists of horse-drawn vehicles a large

portion of which do not enter the hill districts but are limited in

their movements to the large district lying on the lowlands of the

three river valleys or accessible therefrom on moderate gradients. A

great deal of this teaming consists of freight of all kinds received or

shipped at the numerous freight stations on both sides of the river.

The area accessible on roads of easy gradient from each end of these

bridges is very great and includes nearly all the important industrial

plants in Pittsburgh as well as all the freight stations and the

principal warehouses, retail stores and other commercial establishments

of Pittsburgh and Allegheny. Any considerable increase of gradient

on these bridges means a reduction in average size of load hauled by

vehicles of this important class, and a corresponding increase in the

number of trips and in the number of teams required to do the work,

making for increased cost and greater congestion of traffic. For all

horse-drawn vehicles an increase of gradient on the bridges, beyond a

certain limit, means, especially in wet or snowy or frosty weather,

more slipping and falling, more stalling of all bridge traffic by such

accidents, more wear and tear on horse flesh, and a resultant increased

burden on the people. To raise the gradient of the bridges from those

now existing to those indicated in the plans of the local United States

Engineers' office would more than double the traction effort required

in hauling over these bridges.

It must be borne in mind that, as the gradients increase, the cost of

teaming and the wear and tear on teams increases much more rapidly

than the theoretical effective horse power, because of the increased

difficulty of foothold. It is impossible to measure the effect of

any given increase of grade with precision, but a comparison of the

existing conditions with those resulting from various possible bridge

heights will give a good general idea of the effect as shown by the

following tables:

TABLE SHOWING BRIDGE GRADES INVOLVED BY THE ADOPTION OF

VARIOUS CLEARANCE HEIGHTS

----------------------+-----+-----+-----+---------+-----+-----+-----+-----

above pool level of |Pre- | 37´ | 42´ | 47´ |Pre- | 37´ | 42´ | 47´

----------------------+-----+-----+-----+---------+-----+-----+-----+-----

|[33]Maximum gradients |Amount of rise in feet

| | above Duquesne Way

----------------------+-----+-----+-----+---------+-----+-----+-----+-----

Sixth Street bridge | 2.3%| 3.2%| 4.5%| 5.8%[34]| 7.5| 10.4| 15.4| 20.4

Seventh Street bridge | 3.0%| 3.7%| 5% | 6.3%[34]| 10.0| 14.2| 19.2| 24.2

Ninth Street bridge | 2.8%| 3.5%| 5% | 6.5%[34]| 10.1| 13.3| 18.3| 23.3

----------------------+-----+-----+-----+---------+-----+-----+-----+-----

TABLE SHOWING EFFECTIVE ENERGY REQUIRED TO OVERCOME RISE OVER

BRIDGES AT VARIOUS HEIGHTS

===============================================================================

above pool level of | | Present | 37´ | 42´ | 47´

--------------------+ Tons +-----------+-----------+-----------+-----------

|per annum | Foot tons of effective energy

--------------------+----------+-----------+-----------+-----------+-----------

Sixth Street bridge |13,240,010| 99,300,075|137,696,104|203,896,154|270,096,204

| | | | |

Ninth Street bridge |14,732,130|151,740,939|195,937,329|269,597,979|343,258,629

--------------------+----------+-----------+-----------+-----------+-----------

| | Per cent of increase of

| | effective energy required

--------------------+----------+-----------+-----------+-----------+-----------

Sixth Street bridge | | | 38.6% | 105.3% | 172.0%

| | | | |

Ninth Street bridge | | | 29.1% | 77.7% | 126.2%

--------------------+----------+-----------+-----------+-----------+-----------

At the Sixth Street bridge there is at present an undesirably steep

gradient[35] on the Allegheny, or North Side, approach, but it is only

230 feet long and being paved with stone gives a good foothold for

horses. This is to be greatly benefited by filling up the street with

material taken from the "Hump" grading, the plans on file in the City

Bureau of Construction providing for an improved gradient of only 2.22

per cent. Many of the abutters have already waived their damages and

there is no question that the improvement will be made. The present

bridge gradients and those of the Pittsburgh approach are less than

3 per cent. At the Seventh Street bridge the gradients do not exceed

3 per cent, except on the Allegheny approach where it is now being

reduced to 2 per cent. At Ninth Street, while the present bridge

gradients do not exceed 2.8 per cent, there is a short pitch about 100

feet long in the approach on the Allegheny side with a grade of 5.24

per cent.[36] A small amount of regrading, involving no heavy property

damages, will suffice to reduce these gradients to 1.3 per cent, and

appropriations for this improvement have already been made by the City.

The existing grades at the Sixteenth Street, Thirtieth Street and

Forty-third Street bridges are light, but it is not important to

consider these bridges in detail in this connection as it is probable

that the necessity for eliminating railroad grade crossings will

sooner or later alter the existing approaches in such a manner that

the resulting gradients would not be further increased by raising

the bridges. It is to be noted, however, that the precise elevations

recommended by the local office of the United States Engineers for

these bridges would involve serious complications with the railroad

tracks.

In many cities having similarly situated level business and

manufacturing districts along rivers, very large sums of money have

been spent to reduce the gradients on the connecting bridges to less

than 3 per cent, and that figure is rather generally regarded by

engineers as a maximum upon important traffic bridges.

People in Pittsburgh are so accustomed to steep gradients in the

adjacent hill districts that they are apt to ignore the fact that there

is a city within their city, and that this inner manufacturing and

business city is closely confined to the long drawn-out, irregular,

level river-bottoms and is much freer from hills than New York, almost

as much so as Chicago.

The city has expressed its willingness to spend a large sum of money

and undergo great inconvenience for the sake of a moderate reduction

in the street gradients of the "Hump" at one of the gateways of the

hill districts. Important as this work is, it cannot be compared for a

moment as a matter of traffic improvement with the importance attaching

to easy gradients on the bridges, for the streets of the "Hump"

district lead in the main from the flat part of the city to the hilly

part where average loads are limited by the prevailing steep gradients,

whereas the bridges lie between two parts of the level industrial and

commercial city. If at low gradients they serve to unite them; if at

high gradients they divide them.

_Railroad Bridges._--In so far as any changes in the railroad bridges

produce conditions less convenient and expeditious for handling the

business which the people have to do with the railroad, the public has

a direct concern in the matter.

With regard to the Junction Railroad bridge of the Baltimore and Ohio

Railroad System, the raising proposed by the local office of the

United States Engineers, appears to involve no serious difficulties in

operation which would affect the general public or the shippers.

With regard to the Pittsburgh, Fort Wayne and Chicago bridge of the

Pennsylvania System, it is to be noted that this is a double-deck

bridge, the upper tracks being used principally by passenger trains and

the lower tracks by freight trains almost exclusively devoted to local

freight business. The most serious consideration affecting this bridge

is that any very considerable raising of the level of the lower tracks

would throw them out of connection with the important local freight

station to which those tracks run. Even if expense of reconstruction

be wholly disregarded we believe no way can be devised by which the

freight tracks of the Fort Wayne bridge, if raised as proposed by the

local office of the United States Engineers can be connected with

the freight station and industrial plants without involving greatly

increased difficulty and delay in the handling of freight either on

the tracks or in the station itself or in the teaming approaches to

the station. When the large volume of local traffic handled at this

station is considered, it is apparent that such a radical change is a

serious matter for shippers and the great manufacturing and commercial

industries of the city. Other than the expense of making changes in

the bridge and its approaches no serious difficulty stands in the way

of raising the clearance of the main span of the Fort Wayne bridge 2

or 3 feet to about 37 feet above pool level. To go above that figure

involves the serious objections discussed above.

_(b)_ _Effect of Different Bridge Heights Upon River Traffic_.--The

effect upon river navigation of any standard that may be adopted for

the heights of bridges depends upon the heights of the vessels using

the river and the fluctuations of the river level itself. (See Diagrams

4 and 5.)

By means of Davis Island Dam in the Ohio River the water of Pittsburgh

harbor is now kept practically at a minimum stage of six feet above

the datum of zero at natural low water. This is the prevailing water

level for the greater portion of the year. Floods come occasionally,

produced by rains and melting snows, and, of course, with the floods

come increased current velocities. These current velocities of each

river depend upon the source of the flood. When the flood comes down

the Allegheny River high velocities result. When the flood comes down

the Monongahela the high water in the Allegheny is back-water without

excessive currents. Under this condition the Allegheny becomes a

harbor of refuge for Monongahela commerce; and the reverse is true

that in an Allegheny River flood the Monongahela becomes a harbor of

refuge for Allegheny commerce. The floods in the two rivers seldom

come at the same time on account of the differences in the topography

and climatic conditions along the two water-sheds. The most serious

floods in the Allegheny generally come in the spring, when they are

frequently accompanied with drift and ice to such an extent as to

render navigation dangerous. At a stage of 15 feet in an Allegheny

River flood the river current runs at rates of from 4 to 7 miles per

hour. The record of fifty-five years shows that there is an average of

9 days each year when the river is above a 15-foot stage, and this is

mostly in the winter and spring when navigation in the harbor is at its

lowest ebb. There is presented herewith Diagram 4, showing graphically

the average number of days each year during which the river has reached

the various heights indicated.

[Illustration: DIAGRAM SHOWING WATER LEVEL IN ALLEGHENY RIVER--AVERAGE

LAST 53 YEARS]

There is also presented a hydrograph record of the river for four years

past which indicates the conditions ordinarily met with as regards

river stages at various times of year.

[Illustration: Towboat and barge passing under low bridge]

In the balancing of interests between the traffic on the river and

that across the bridges, it is believed to be fair and just that

for boats of excessive size and height the navigation of the river

above a 15-foot stage be eliminated from the problem; (1) because of

the comparatively small number of these boats; (2) because of the

questionable necessity of having such high boats at all; (3) because

of the period of the year when these extreme stages are reached; (4)

because these periods of time are so limited in length; (5) because

of the generally accompanying swift currents, and (6) because of the

oft-times accompanying dangerous floating drift and floating ice.

[Illustration: Closer view of such boats]

As to the height of vessels, it is to be noted that the great bulk of

navigation under the bridges is not through traffic, but is simply

movements about in the lower stretch of the river which forms part of

the harbor of Pittsburgh. The commodities moved are nearly all sand,

gravel and coal in barges, which loads are almost invariably taken up

stream while the downward movement is mostly of empty barges. These

barges are mostly moved by harbor tugs. The harbor tugs actually in use

are from 22 to 27 feet high, averaging about 24 feet.

[Illustration: Allegheny River heights for each day, 1906-1907.--U. S.

Engineers' Report (Diagram 5)]

[Illustration: Allegheny River heights for each day, 1908-1909.--U. S.

Engineers' Report (Diagram 5)]

The heights of the Monongahela standard towboats vary from 24 to 32

feet, averaging about 28 feet. Out of a list of 28 such boats but 5

exceed 28 feet in height.

The few packet boats running on the river are of moderate height and

can be accommodated in the harbor under the bridges at ordinary river

stages. The amount of business that could be done by a few packet boats

of extreme and unnecessary height is so small that to raise the bridges

to a sufficient height to accommodate it would place an entirely

unjustifiable tax and inconvenience upon the far greater business

interest of the city concerned in crossing the river.

The following tables show the average number of days per annum during

which various types of existing vessels would be prevented from

navigation by bridges of various assumed heights above the Davis Island

Pool:

TABLE SHOWING EFFECT OF VARIOUS CLEARANCE HEIGHTS UNDER BRIDGES

=============================================================================

height above pool |bridge | 37 | 42 | 47 |bridge | 37 | 42 | 47

level in feet | 33 | | | | 33 | | |

---------------------+-------+------+------+------+-------+------+------+----

|Total number of days per |Total number of days per

Types of Vessels |annum when clearance |annum when clearance would

|would be insufficient. |be insufficient excluding

| |days when river is above

| |15-foot stage.

---------------------+-------+------+------+------+-------+------+------+----

height 24´ | 12 | 3 | 1 | 1 | 3 | 0 | 0 | 0

| | | | | | | |

height 27´ | 36 | 9 | 1 | 1 | 28 | 0 | 0 | 0

| | | | | | | |

ordinary maximum | 57 | 12 | 2 | 1 | 48 | 3 | 0 | 0

| | | | | | | |

extreme maximum | 198 | 57 | 9 | 1 | 189 | 48 | 0 | 0

---------------------+-------+------+------+------+-------+------+------+----

In drawing conclusions from the above table, as a basis for plans

governing the expenditure of millions of dollars in construction and

the permanent establishment of conditions of navigation and of traffic

over the bridges and the enormous business interests concerned, it is

important to bear in mind that the types of vessels here considered

are antiquated, and can undoubtedly be materially changed in many

particulars to the benefit of all interests.

As bearing directly on this question of boats and bridges, attention

is invited to the following extract from the report of Hon. D. S.

Alexander, chairman of the River and Harbor Committee of the United

States House of Representatives, in submitting for action of the House

the last River and Harbor bill on February 11th, 1910:

_Modern Type of Boats for Non-tidal Rivers._--"The British Government

has been designing shallow-draft boats for use on the Nile, and the

German and Austrian governments have been working along similar lines

with reference to methods of transportation on the Rhine, the Danube,

the Elbe and other waterways. The boats designed have been very

successful, having been used in connection with modern loading and

unloading appliances. On our western rivers little change has been made

in the design of towboats, barges, etc., since 1860, and it is believed

that a design embodying the best points of modern vessels, with modern

machinery and cargo handling devices, might lead to a marked increase

in the traffic on the non-tidal rivers of the United States, especially

after permanently improved channels are available.

"It is believed that the appropriation of $500,000 to be expended

in the purchase of plant for use in connection with the work of

improvement of the river will also provide for experiments to be

carried on by the Government which will result in improving the present

type of river freight carriers; and also that these tests can be made

in no other way, since the expenditures and uncertainties involved

preclude the use of private capital for the purpose. As a result of the

tests or experiments it is hoped that a large saving to the country at

large may accrue from decreased costs of transportation, and that a

type of carrier may be developed which will also reduce the cost of all

bridges across navigable streams due to lessened requirements in the

matter of head room."

This report of Colonel Alexander, the very able Chairman of the River

and Harbor Committee of the House of Representatives, is worthy of

serious consideration. Such an investigation and experiments to

determine the best type of carriers to use on the river seems certain

to be provided for and may result in clearly demonstrating that

no necessity exists for raising the Allegheny bridges at all, in

accordance with the possibility outlined by the closing paragraph of

Colonel Alexander's report above. The appropriation of $500,000 as

recommended by Colonel Alexander is included in the River and Harbor

bill which has passed the House of Representatives and Senate. There is

every probability that it will become a law.

A vast amount of water traffic is carried on inland waterways all

over the world under fixed bridges with far less head room than is

provided for under the Allegheny River bridges. It is customary in

other parts of the country and the world to establish for rivers a

minimum head room for bridges at a high navigable stage, which stage

is considerably lower than the maximum or even the ordinary high flood

stage. For instance, in the new barge canal being built by the State

of New York at a cost of $108,000,000 the minimum head room under all

stationary bridges is fixed at 15½ feet at the _high navigable_ stage

of the water. The high _navigable_ stage is based chiefly upon what is

a _safe_ navigable stage, taking everything into consideration. It is

by no means a very high stage. As this canal runs through the canalized

Mohawk, Oneida, Oswego, Seneca and Clyde rivers, the situation is

comparable with that on the Allegheny. The depth of the canal at low

water is to be 12 feet, so it is seen that the clear head room is but

about 25 per cent greater than the minimum depth of the water. _The

boats must be made to fit the bridges, and not the bridges to fit the

boats._ It is estimated that the amount of traffic which will pass

through these canals about 450 miles long and under these 15½-foot

bridges will be about 20,000,000 tons annually, many times the amount

making use of the Allegheny River. The present Erie, Champlain and

Oswego canals in the State of New York, which have been in operation

for about 80 years, are crossed by several hundred bridges giving a

clear head room of 13 feet. No complaint about this head room is known

to exist, notwithstanding that steam vessels are largely used for

navigation purposes on the canals. _The boats have to be made to fit

the bridges and not the bridges to fit the boats._

At Paris, the river Seine running through the city carries a very large

amount of business. Annually about 20,000,000 passengers, and about

11,000,000 tons of freight are carried on boats of various kinds.

There are 36 bridges which span the river and must be passed by the

water-borne traffic. The clear head room under these bridges at the

highest navigable water varies from 11.25 feet to 21.88 feet. By

highest navigable water is meant the stage of water when by reason of

floods or currents, navigation ceases. This Paris water-borne freight

traffic on the Seine amounts to fully 7 times that of the Allegheny

River and passes under 5 times as many bridges, with minimum available

head room at high navigable stages just about one half that under the

present bridges over the Allegheny at a 15-foot stage. The conditions

of navigation on the Seine at Paris are practically the same as those

on the Allegheny at Pittsburgh. _In Paris the boats are made to fit

the bridges and not the bridges to fit the boats._

From these and many other illustrations that could be given it is

evident that it is not universally or even commonly considered

necessary or advisable to sacrifice business interests crossing the

bridges to navigation interests using the waterways, to any such extent

as that demanded by the navigation interests of the Allegheny River.

_Conclusions as to Clearance Heights._--Disregarding for the moment

the question of the time when changes in the present bridges should be

required, it is believed, after very careful consideration, that the

conditions brought out by our study of the problem would best be met

by fixing the elevation for a substantial portion of each bridge in

the center at a clear height above the pool level of substantially 37

feet, or 28 feet above the river at a 15-foot stage at each bridge. It

is believed that this elevation will give fair, justifiable and all

really needed accommodations to the navigation interests. This height

can be attained without extravagant and unjustifiable expense and

inconvenience to the business interests involved in crossing the river,

and while it cannot be hoped that it would be satisfactory to the

extreme advocates of river and harbor interests, it ought to satisfy

those who are able and willing to give proper and fair consideration

to other interests than their own. There are no reasonable navigation

demands, with bridges at this elevation, that cannot be met if the

water-borne commerce be conducted with vessels of the best modern

accepted type and not of extreme or unnecessary height.

_Piers and Channels._--For the benefit of the navigation interests

there are certain changes in some of the bridges over the Allegheny

that should be made without question. These relate to the location of

piers and location and width of the navigable channels.

[Illustration: Bridges over the Seine, Paris, showing low clearance

heights required and shallow water]

At the extreme mouth of the Allegheny River a new bridge, the North

Side Point bridge, has been approved by the War Department and is to

be built. This is to have one central pier dividing the river into two

channels.

A short distance above this North Side Point bridge is situated the

Sixth Street bridge, in some respects the most important highway

structure crossing the river. This bridge now corresponds to the North

Side Point bridge in having a central pier and dividing the river into

two main channels of ample width of over 400 feet.

The next bridge, the Seventh Street bridge, also has now a central pier

with channels about 320 feet width on each side of it. The next bridge

up the river, that at Ninth Street, has shorter spans, with the piers

so unfortunately located as to be decidedly obstructive. As this bridge

is of relatively light construction it is possible that the heavy and

constantly increasing traffic which it is called upon to bear will

before long necessitate its reconstruction anyway, and it will not be

unreasonable to require it to be rebuilt with fewer piers properly

located to conform to the plan adopted for the Sixth Street and Seventh

Street bridges.

As a permanent arrangement of piers for the above three bridges either

of two logical plans may be adopted. The first is to retain the

existing two-spans center-pier arrangement of the Sixth Street and

Seventh Street bridges, conforming to the center pier plan required

by the United States Engineers for the new North Side Point bridge,

and reconstruct the Ninth Street bridge upon the same general plan.

The other is to reconstruct all three bridges with two piers and three

spans each, as recommended by the local office of the United States

Engineers. The first or central pier plan has the merit of economy of

construction in that it involves the construction of no new piers for

the Sixth Street and Seventh Street bridges, and permits the continued

use of the existing superstructures of the Sixth Street and Seventh

Street bridges by simply raising them to the elevation that may be

decided upon and ordered. So far as we can ascertain, in view of the

center pier plan adopted for the North Side Point bridge, the advantage

to navigation appears to lie on the side of adhering to a center pier

plan for these bridges also. On the other hand, there is no doubt that

three-span bridges could be made more agreeable in appearance than

two-span bridges. But the possible gain in appearance alone does not

appear sufficient to justify the adoption of three spans.

The next bridge above Ninth Street is that of the Pittsburgh, Fort

Wayne and Chicago Railroad. This has been constructed with two main

piers providing one main central channel 337.5 feet wide and three

other piers giving four channels from 155 to 163 feet wide. Owing to

the bend in the river at the bridge and the distance above the Ninth

Street bridge, there is no valid objection to this single main central

channel at the railroad bridge connecting either with two channels

divided by the central piers of the bridges below, or with a central

channel if those bridges should be reconstructed on the three-span plan.

[Illustration: Paris bridges and boats--low boats to fit bridges]

The Sixteenth Street bridge has been constructed with 3 piers dividing

the river into 4 channels of about 150 feet each; the clear head room

beneath it is less than that now given by the bridges below it. The

best arrangement to be made with this bridge is to require it to be

rebuilt without the central pier, leaving a central channel about

320 feet in width between the two side piers to correspond with the

railroad bridge just below it. It is an old, covered, wooden bridge, in

poor physical condition, and, as previously noted, it is probable that

it must be raised anyhow in connection with eliminating railroad grade

crossings on the approaches.

The Thirtieth Street bridge has its piers properly spaced to leave a

central channel 285 feet in clear width and no changes are required in

pier and channel location at this bridge.

The Thirty-third Street or Pittsburgh Junction Railroad bridge of the

Baltimore and Ohio System has 3 piers, giving a main central channel

of 232 feet wide, with side channels 195 feet wide, and on the Herrs

Island side of 150 feet. No change is needed in the location of the

piers and channels at this bridge.

The Forty-third Street bridge is built with 3 piers, making 4 channels

each of about 160 feet wide. It gives less clear head room at high

river stages than most of the lower river bridges. It is an old wooden

bridge, in poor physical condition. The best arrangement for this

bridge is to treat it as the Sixteenth Street bridge, and to require

it to be rebuilt, omitting the central pier and leaving a central

channel about 300 feet wide, to correspond with the bridges below it.

The elimination of railroad grade crossings on the approaches to this

bridge is already a pressing public need and must soon result in its

raising or reconstruction at a higher level.

_Considerations against Requiring Changes in Bridges To Be Made at

Present._--The following important questions, having a direct bearing

upon the proper design of permanent bridges across the Allegheny River,

are now under consideration:

1. The Flood Commission is getting data for studying the question of a

protective embankment along the river front, and of the proper grades

of streets and bridge approaches in the region subject to inundation.

The design of such flood-protection works should have important bearing

upon the grade, location and design of the permanent bridge abutments.

This Commission is also studying the question of impounding the flood

waters of the Allegheny and Monongahela Rivers in their upper valleys,

which may result in materially lessening the height and velocity of

floods in the harbor of Pittsburgh, and consequently, simplify the

bridge and navigation problems of the harbor.

2. The question of the best routes for surface cars and rapid transit

lines crossing the Allegheny River is now being studied for the City as

a part of a comprehensive plan for traction improvements. The result of

these studies might readily affect the design of the new bridges.

3. The government experiments recommended by Colonel Alexander of the

River and Harbor Committee and authorized in the River and Harbor bill

just passed by Congress and providing for the development of a more

economical and efficient type of river-boats, requiring less head

room than the present antiquated types, may soon show results that

would have a decided influence in determining the reasonable clearance

heights of bridges.

[Illustration: A typical Paris boat and tows]

4. Attention is also invited to the fact that the people of Pittsburgh

have voted to expend about $7,000,000 in certain public improvements.

Among these are the cutting down of the "Hump," an obstructive hill

in the city's midst, widening some streets and filling certain other

streets in the North Side and West End that are flooded at high river

stages. The material from the "Hump" in the vicinity of the Court House

is to be hauled to these North Side streets across the lower Allegheny

bridges under question. The work is of great magnitude and it will

take at least two years to complete it. Any material alteration to

the bridges such as proposed by the Board of Engineers will require

a long time to be carried into effect. While this bridge work would

be under way, the transportation of the material excavated from the

"Hump" and the filling up of the low grade streets of the North Side

would have to cease or would be carried on with great difficulty and

inconvenience to other traffic. This would tie up the whole work while

it is in progress, causing material injury to the city, for it is to

be extremely annoying and bothersome while it is in progress, and the

longer this period is strung out the worse it will be.

For all of the above reasons we believe that to precipitate the actual

reconstruction of the bridges at this time would be most undesirable

for the city and prejudicial to the best results, in the long run, for

all concerned.

RECOMMENDATIONS

In conclusion we beg to recommend as follows: 1. That the Sixteenth

Street and Forty-third Street bridges, which are obstructions to

navigation on account of their pier locations, narrow channels,

and exceptionally low clearance height, be required to be rebuilt

with their piers so located as to give channels conforming to the

neighboring bridges, and that their elevation be fixed with regard

to eliminating the railroad grade crossings on their approaches, but

the minimum clearance shall be fixed in accordance with the closing

paragraph below.

2. That the Ninth Street bridge should be rebuilt as soon as

practicable with a center pier and two wide spans conforming to those

of the Sixth Street and Seventh Street bridges. The design of the new

Ninth Street bridge, however, should not be finally determined and

erection begun until a definite plan for comprehensive improvements in

the traction system between the two sides of the river has been decided

upon. Unless new circumstances develop before the construction of this

bridge is begun that materially affect the problem of clearance height,

the elevation should be fixed in accordance with the closing paragraph

below.

3. That all questions pertaining to changing the elevation of the Sixth

Street, Seventh Street, Fort Wayne, Thirtieth Street and Junction

Railroad bridges be deferred to await the report of the Pittsburgh

Flood Commission and the resultant action; to await the report on a

comprehensive plan for traction improvements; to await the completion

of the work projected by the City in cutting down some streets and

filling others; and to await the results of investigation of river-boat

design and construction provided for in the River and Harbor bill just

passed by Congress.

4. That, if it is deemed essential and necessary at present to decide

upon the elevation to which all Allegheny River bridges must be made to

conform, this elevation be fixed so that there shall be a clear head

room of substantially 37 feet above pool level, varied so as to give

at each bridge a clear head room of 28 feet when the river is at a

15-foot flood stage. This height to be maintained over the entire main

span where there is a central span and for 180 feet on each side of the

central pier where there is a central pier.

We have the honor to be, very respectfully,

Your obedient servants,

THOMAS W. SYMONS,

Col. Corps Engineers U. S. A., retired,

FREDERICK LAW OLMSTED.

APPENDIX I

_Amount and Importance of Bridge Traffic._--_Highway Bridges._--The

following table gives the records of counts made in the fall of 1909,

and spring of 1910 on the various bridges over the Allegheny River:

RECORD OF COUNTS.--TABLE NO. 1

==============================================================================

----------------+---------+------+--------+--------+------+-------+-----------

Sixth Street |Aug. 24- |89,354| 55,791| 79,247| 9,534| 24,583| 1,605,793

| Oct. 23 | | | | | |

Ninth Street |Aug. 26- |72,854| 8,961| 14,846| 613| 960| 185,158

Sixteenth Street|Oct. 4- | ... [37]4,444[37]7,764| ... | ... | 76,495

| Oct. 17 | | | | | |

Thirtieth Street|Aug. 24- | ... | 9,844| 10,184| 667| 447| 96,485

| Oct. 23 | | | | | |

Forty-third |Aug, 23- | ... | 8,159| 8,165| 987| 2,179| 130,744

Street | Nov 1 | | | | | |

----------------+---------+------+--------+--------+------+-------+-----------

RECORD OF COUNTS.--TABLE NO. 1A[38]

============================================================================

--------------+----------------+---------+--------+------+------+-----------

Seventh Street|Feb. 28-Mar. 3, | 401 | 4,800 | 273 | 1,035| 29,146

| 4, 5, 7 | | | | |

--------------+----------------+---------+--------+------+------+-----------

Assuming that the average number of vehicles per day and the average

tonnage per day are the same throughout the year as during the periods

of counting, we deduce the following results:

TRAFFIC FOR YEAR 1909.--TABLE NO. 2

===================================================

-----------+--------+-------+-------+-------+------

6th St. | 1909 |534,652|333,829|474,171|57,013

| | | | |

9th St. | 1909 |738,650| 90,812|150,490| 6,205

| | | | |

16th St. | 1909 | ... |115,851|202,429| ...

| | | | |

30th St. | 1909 | ... | 58,875| 60,919| 3,979

| | | | |

43d St. | 1909 | ... | 42,522| 42,559| 5,147

-----------+--------+-------+-------+-------+------

============================================================

Location of|Auto- |Pedestrians|[39]Gross | [40]Total value

bridges |mobiles| | tonnage |

-----------+-------+-----------+----------+-----------------

6th St. |147,095| 9,608,406 |13,240,010|[41]1,879,140,750

| | | |

9th St. | 9,709| 1,877,268 |14,732,130| 2,201,473,500

| | | |

16th St. | ... | 1,991,988 | 967,544| 102,201,375

| | | |

30th St. | 2,664| 577,320 | 398,430| 44,233,500

| | | |

43d St. | 11,351| 681,710 | 311,090| 32,478,500

-----------+-------+-----------+----------+-----------------

TRAFFIC FOR YEAR 1909.--TABLE NO. 2A[42]

====================================================

Location of bridges|Passenger|Delivery|Single|Double

|vehicles |vehicles|trucks|trucks

-------------------+---------+--------+------+------

Seventh Street | 29,273 | 351,400|19,929|75,555

-------------------+---------+--------+------+------

========================================================

Location of bridges|Pedestrians|[39]Gross|[40]Total value

| | tonnage |

-------------------+-----------+---------+--------------

Seventh Street | 2,127,585 |1,159,084| 149,862,600

-------------------+-----------+---------+--------------

_Railroad Bridges._--The bridge carrying the heaviest traffic is that

of the Pittsburgh, Fort Wayne and Chicago Railroad, a part of the

Pennsylvania System, which forms one of the links in the main line of

this railroad system between the East and West. Across this bridge are

carried each year about 2,750,000 passengers, 32,000 tons of mail, and

53,000,000 tons of freight and general railroad traffic, besides about

2,135,000 pedestrians,[42] making it one of the greatest throats of

commerce in the country. This is a double deck bridge of 4 tracks, 2

tracks on each deck, with a wide footway on the lower deck. It is to be

noted that the amount of traffic passing over this bridge is about 25

times as much as that which floats on the water beneath it, and is far

higher in quality and value per ton.

The other railroad bridge crossing the river within the city limits is

the Thirty-third Street viaduct of the Baltimore and Ohio Railroad.

This is a link in the Baltimore and Ohio Railroad between the East and

the West and carries an enormous traffic amounting each year to about

217,000 passengers and 24,330,000 tons of freight, express and other

trains.

Uniting this with the traffic over the Fort Wayne bridge of the

Pennsylvania we have crossing the Allegheny River on the two railroad

bridges a gross amount of 77,330,000 tons, and 5,102,000 passengers and

pedestrians, with a value of tonnage traffic estimated at approximately

$4,957,000,000.

APPENDIX II

_Amount and Importance of River Traffic._--The following statistics

were obtained from the United States Engineers' office and show the

number of boats, net tonnage and number of passengers passing Dam No. 1

in the Allegheny River during the year 1909:

TABLE NO. 1

================================================

Month |No. vessels|No. passengers|Tonnage of

| | | cargoes

----------+-----------+--------------+----------

January | 338 | 16 | 30,889

February | 358 | 18 | 30,073

March | 1,055 | 25 | 81,424

April | 732 | 197 | 51,457

May | 896 | 1,506 | 57,269

June | 958 | 1,248 | 56,324

July | 901 | 2,495 | 37,888

August | 868 | 2,019 | 29,102

September | 1,006 | 1,681 | 36,759

October | 955 | 982 | 53,622

November | 789 | 616 | 42,827

December | 495 | 231 | 29,086

----------+-----------+--------------+----------

Total | 9,351 | 11,034 | 536,720

----------+-----------+--------------+----------

The following are statistics of counts taken in 1909 at the different

bridges:

TABLE NO. 2

-------------------------+---------------------------+----------------

| | No. of vessels

Location of count | Period covered by count | passing

-------------------------+---------------------------+----------------

Sixth Street Bridge | Aug. 24-Oct. 23 (61 days) | 4,534

Ninth Street Bridge | Aug. 26-Sept. 30 (36 days)| 3,279

Fort Wayne Bridge | Aug. 20-Oct. 28 (70 days) | 4,925

Thirtieth Street Bridge | Aug. 24-Oct. 23 (61 days) | 2,022

J. R. R. Bridge | Sept. 13-Nov. 13 (60 days)| 1,460

Forty-third Street Bridge| Aug. 23-Nov. 1 (70 days) | 1,580

-------------------------+---------------------------+----------------

Assuming that the ratio between the number of vessels during any given

period and the total for the year is the same at all bridges as at

Dam No. 1; and assuming that the relative number of different kinds

of vessels are the same at all bridges; and further assuming that the

average weight of cargo is the same at all bridges as recorded at Dam

No. 1, we reach the estimates of total traffic under the bridges given

in Table No. 3.

FOR THE YEAR 1909--TABLE NO. 3

-------------------------+--------+-----------+-----------+------------

| | | | [43]Wt. of

Location of count | No. of |[43]Weight | Weight of | vessels

|vessels |of vessels | cargoes | and cargoes

-------------------------+--------+-----------+-----------+------------

Sixth Street Bridge | 21,763 | 1,097,378 | 1,247,020 | 2,344,398

Ninth Street Bridge | 25,904 | 1,311,823 | 1,484,299 | 2,796,122

Fort Wayne Bridge | 20,685 | 1,043,020 | 1,185,250 | 2,228,270

Thirtieth Street Bridge | 9,706 | 489,416 | 556,154 | 1,045,570

J. R. R. Bridge | 8,030 | 404,905 | 460,119 | 865,024

Forty-third Street Bridge| 6,636 | 334,613 | 380,243 | 714,856

-------------------------+--------+-----------+-----------+------------

The largest total, that passing under the Ninth Street bridge, is

without doubt somewhat less than the total traffic on the river, and

a careful study of the figures would seem to indicate that the total

water-borne traffic of the Allegheny River in 1909 amounted to about

one and three-quarter (1¾) million tons of cargo or three and one-half

(3½) million tons gross displacement, including cargoes, barges, tugs

and all vessels.

The water-borne commerce on this river is of the cheapest character,

consisting almost entirely of sand and gravel dredged from the rivers

and coal floated down the Monongahela and delivered along the shores.

All this sand, gravel and coal is carried in low-lying barges or scows

moved by tugs or towboats.

A small amount of package freight comes in and leaves by packet boats.

TABLE NO. 4

TONNAGE PASSING DAM NO. 1 DURING YEAR 1909. (OBTAINED FROM

UNITED STATES ENGINEERS)

Coal 231,232 tons

Other iron or steel products 428 tons

Sand 132,894 tons

Gravel 123,579 tons

Brick 75 tons

Stone 3,869 tons

Timber 8,519 tons

Lumber 3,519 tons

Pit posts 13,950 tons

Braces 600 tons

Railroad ties 6,650 tons

Wood 45 tons

General merchandise 3,119 tons

New barges 2,628 tons

New boats (coal) 3,940 tons

Manure 1,000 tons

Bark 455 tons

The average value of the freight based on prices prevailing in 1910

is about $3 a ton. The average value of the carriers is about $65 a

ton. As there is a slightly greater weight of freight than carrier,

an average of $30 per ton would be a fair estimate of the value of

freight and carriers. The total value of the water-borne traffic of

the Allegheny River for the year under the various bridges would,

therefore, be about $105,000,000.

The passenger traffic on the river is so small that it may be

considered negligible. It is estimated at 35,000, largely pleasure

traffic in small boats.

About one-third as much tonnage goes through Lock No. 2 as through

Lock No. 1, and about one-sixteenth as much goes through Lock No. 3

as through Lock No. 1. There is no navigation on the river above the

third pool. It is claimed, however, that with the further canalization

of the river above Dam No. 3 and the raising of the bridges this

traffic would be greatly increased. It is to be hoped that there will

be a considerable increase, but there are distinct limitations on the

probable amount of the increase. The Monongahela has a larger and

more highly favored local territory to draw upon for freight than the

Allegheny so that under the best of conditions, with every possible

improvement of navigation, the traffic on the Allegheny can never be

expected to approach that upon the Monongahela.

The total amount of freight of all kinds passing Dam No. 1 on the

Monongahela in 1909, was 5,417,873, or a little more than ten times the

amount on the Allegheny, while the tonnage passing over the Allegheny

bridges is thirty times greater than the tonnage on the Allegheny

River.[44] Yet, if conceivably the traffic on the Allegheny should

equal that now on the Monongahela, it would still be only one-third

that _over_ the Allegheny bridges.

Since the figures for the present traffic over the Allegheny River

bridges are used for comparison with the present river traffic, and

since the former must continue to grow steadily with the growth of

the Pittsburgh industrial district, it seems quite clear that no

conceivable growth in the latter can seriously affect the overwhelming

predominance of the bridge traffic in amount and value.[44]

FOOTNOTES:

[32] Appendix II.

[33] The maximum gradients here given assume the improvement of the

short pitches now existing on some of the bridge approaches.

[34] Gradients for this clearance height are greater than those shown

on United States Engineers' plans because of greater width of channel.

If United States Engineers' plans were adopted the maximum gradients

would be as follows: Sixth Street, 4.35%; Seventh Street, 4.93%, and

Ninth Street, 4.98%.

[35] 3.64 per cent (United States Engineer's Office) or 4.0 per cent,

(City Bureau of Construction.)

[36] Given as 6.35 per cent on United States Engineers' Sections.

[37] Automobiles and carriages included in counts for light and heavy

wagons.

[38] Table 1A. The count at Seventh Street bridge was recorded by

different units and, therefore, required a separate table. The North

Side approach to this bridge was being improved at the same time the

count was made, causing a temporary interference with travel reflected

in an abnormally small proportion of traffic on the bridge and a

corresponding increase for the adjacent bridges.

[39] In estimating the gross tonnage, the following average weights

were used: a street car with average load--19 tons; a heavy wagon

(including team), averaging loaded and empty vehicles--4 tons; a light

wagon (including team), averaging loaded and empty vehicles--1.75 tons;

an automobile or carriage (including team),--.9 tons; pedestrians and

passengers are figured at 150 pounds apiece.

[40] Estimating heavy and light wagons, including team and load at $125

per ton; carriages and automobiles, including teams, at $300 per ton;

cars at $160 per ton and live stock at $200 per ton, we get an average

tonnage value of $150 over the Sixth Street, Seventh Street[41] and

Ninth Street bridges, and $125 over the Sixteenth Street, Thirtieth

Street and Forty-third Street bridges.

[41] The figures for pedestrians, passengers and general tonnage are

taken from the affidavit of John C. Perrott. The tonnage of mail was

obtained from the report of the U. S. Post-office Department.

[42] See Note under Table 1A.

[43] The following data as to weight of vessels was kindly furnished by

Mr. J. F. Tilley:

WEIGHTS OF RIVER CRAFT WITHOUT FREIGHT

Medium tows 800 tons

Pool tows 175 tons

Barges 55 tons

Coal boats 105 tons

Flats 30 tons

In estimating we assumed the following average weights for river craft,

based in large measure upon the above data:

Steamboats 225 tons

Coal boats and barges 80 tons

Barges 55 tons

House boats, excursion boats, yachts, and U. S. Government boats 45 tons

Launches, skiffs, etc. 1 ton

Motor boats and miscellaneous 10 tons

[44] See Diagrams 1, 2 and 3.

INDEX

Allegheny River Boulevard, 79.

Allegheny River Bridges, 133-165.

Allegheny River Heights, 145-149.

Allegheny River Parkway, 120.

Amount and Importance of Bridge Traffic, 137, 138, 160-162.

Amount and Importance of River Traffic, 138-140, 162-165.

Amount and Importance of Traffic Affected, 137-140.

Appendix I, Bridge Report, 160-162.

Appendix II, Bridge Report, 162-165.

Ardmore Thoroughfare, 73.

Areas Reached by High- and Low-level Tunnel Routes, 54.

Arlington Avenue and Washington Avenue Connection, 85.

Aspinwall Bridge, The, 59, 60.

Baltimore Surveys, 100.

Batavia Street, 71.

Bates Run Connection, 63, 64.

Baum Street Improvement, 65.

Beechview Thoroughfare, 83.

Beechwood Boulevard Connection, 68, 69.

Beechwood Boulevard Parkway, 120, 121.

Beechwood Boulevard Re-alignment, 70.

Bell Avenue Extension, 73.

Bellefield Improvement, The, 101-106.

Bluff Street Hillside, 122.

Boats for Non-Tidal Rivers, 151-153.

Boundary Street Improvement, 69.

Braddock Avenue--Northerly End, 72.

Braddock Avenue Viaduct, 72.

Bridge Report, Special, 133-165.

Bridges over the Seine, Paris, 154.

Bridge Street Improvement, 78.

Bridge Traffic, 137, 138, 160-162.

Brighton Road Connection, 75, 76.

Brighton Road Viaduct, 76.

Brownsville Road, 86.

Butler Street Improvement, 59.

California Avenue and Brighton Road Extension, 75, 76.

Carrick Connection from the South Hills Tunnel, 84, 85.

Carson Street, 79, 80.

Center Avenue Improvement, 65.

Chartiers Avenue Grade Crossing, 80.

Chartiers Valley Parks, 118.

City and the Allegheny River Bridges, The, 133-165.

Civic Center, A, 11-17.

Clearance Heights, Conclusions as to, 153.

Comparison of Bridge and River Traffic, 140.

Considerations against Requiring Changes in Bridges to be made at

Present, 157-159.

Corliss Street, 80, 81.

Cost of Living in Pittsburgh, XIII.

Crafton-Carnegie Connection, 81.

Crafton Hillside Thoroughfare, 81.

Diamond Street Widening, 17.

Down Town District, The, 5-30.

Dravosburg and Mifflin Township Thoroughfares, 74-75.

Duquesne Bridge, 75.

Eastward Arteries and Their Improvement, 6-9.

East Liberty Improvements, 65-67.

East Ohio Street, 77, 78.

East Street, 76, 77.

Effect of Different Bridge Heights upon River Traffic, 145-151.

Effect of Various Possible Bridge Heights upon the Traffic Over the

Bridges, 141-145.

Effect of Various Solutions, 140.

Eighth Avenue Branch to Dravosburg, 75.

Eighth Avenue Branch Westward, 75.

Eighth Avenue Improvement, 75.

Ellsworth Avenue Extension, 62.

Etna Improvement, 78.

Etna Park, 118.

Etna Playground, 118.

Fairhaven County Road, 84.

Fifth Avenue--Center Avenue Connections at Soho, 61, 62.

Forbes Street--Fifth Avenue Connection at Soho, 60, 61.

Forbes Street Artery, 47-49, 60, 61.

Forbes Street Extension, 72, 73.

Forty-third Street Bridge, 59.

Full Report (Allegheny River Bridges), 134-165.

General Map of the Pittsburgh District, Facing page 1.

General Plan of Down Town District, Facing page 9.

Glenwood Bridge, 64, 65.

Grade Crossings, 10, 56, 57, 59, 64, 71, 75, 78, 79, 80.

Grant Boulevard, 106-108.

Grant Boulevard Extension, 11.

Greenfield and Squirrel Hill Extension, 64.

Greenfield Avenue Connection, 64.

Greensburg Pike, 74.

Greensburg Pike South of Turtle Creek, 74.

Guyasuta Park, 120.

Haights Run Bridge, 59.

Haights Run Thoroughfare, 67, 68.

Haights Run Valley Park, 121, 122.

Hamilton Avenue Extension, 65, 66.

Hazelwood Grade Crossing, 64.

Highway Bridges, 141-144, 160, 161.

Hillsides, Steep, 100-112.

Howley Street Connection, 58.

"Hump Cut," The, 10, 11, 128-132.

Index to Outlying Thoroughfare Improvements, 88-91.

Introduction, 1-4.

Introduction (Allegheny River Bridges), 133.

Lang Avenue Connection, 83.

Larimer Avenue Extension, 66.

Letter of Transmissal, XI.

Lowry's Lane, 77.

Main Arteries (Main Thoroughfares), 44-56.

Main Arteries (The Down Town District), 5, 6.

Main Street Grade Crossing, 79.

Main Thoroughfares, 31-92.

Management and Cost of Surveys, 98.

Maps of Surveys, 96-98.

Market Street Widening, 17, 18.

Market, The, 18, 123-128.

Meadow Street Connection, 68.

Millvale Playground, 118.

Millvale Thoroughfare, 78.

Modern Type of Boats for Non-tidal Rivers, 151-153.

Monongahela Hillside Thoroughfare, 62, 63.

Moultrie Street Playground, 117.

Mt. Washington Hillside, 122.

Murray Avenue Extension, 69, 70.

Need for Surveys, Pittsburgh's, 93, 94.

Negley Run Boulevard, 66.

Negley Run Parkway, 121.

Neighborhood Parks, 113-116.

New York Surveys, 98, 99.

Nine Mile Run Park, 119, 120.

North Side Improvements, 75-77.

Objects to Be Secured by Surveys, 94, 95.

Ohio Street, East, 77.

Outlying Thoroughfare Improvements, 56-92.

(Index, 88-91.)

(Map, 92.)

Park Opportunities, Special, 117-122.

Parks and Recreation Facilities, 101-122.

Parks, General Discussion, 113-117.

Penn Avenue Artery, 44-46.

Penn-Liberty Connection at Howley Street, 58.

Piers and Channels, 153-157.

Plan for the Proposed Hump Cut, 129.

Point, The Improvements of the, 29, 30.

Purpose of the Report, XIII.

Railroad Bridges, 144, 145, 161, 162.

Rankin Improvement, 72.

Rankin Playground, 118, 119.

Recommendations (Allegheny River Bridges), 133, 134, 159, 160.

Recommendations, Specific (Main Arteries), 44-56.

Recommendations, Specific (Outlying Thoroughfares), 56-92.

Recommendations, Urgent, 2, 3.

River Traffic, 138-140, 162-165.

Rural Parks, 116, 117.

Sample Maps, 98.

Sassafras Street Outlet, 58.

Sawmill Run Hillside Thoroughfare, 83, 84.

Sawmill Run Parkway, 119.

Sawmill Run Thoroughfare, 81, 82.

Second Avenue Extension, 70, 71.

Second Avenue Freight Yards, 10.

Sharpsburg Bridge, 59.

Silver Lake Playground, 121.

Sixteenth Street Bridge, 56.

Sixth Avenue, 9, 10.

Soho Connections, 60-62.

South Eighteenth Street, 85, 86.

Southern Avenue Connection, 82, 83.

South Hills Artery, 49-56, 81-85.

South Hills Tunnel and Thoroughfare Routes, Profiles of, 53.

South Side Improvements, 49-56, 79, 85-87.

South Tenth Street, 86.

Special Park Opportunities, 117-122.

Special Reports, 123-165.

Special Types of Thoroughfares, 34-37.

Squaw Run Park, 120.

Squaw Run Thoroughfare, 79.

Stanton Avenue Connection to the Lincoln District, 68.

Steep Hillsides, 109-112.

Streets Run, 74.

Surveys and a City Plan, 93-100.

Sycamore Street Grade Crossing and Bridge Street Improvement, 78.

Technical Procedure for Surveys, 95, 96.

Thirty-third Street Improvement, 57, 58.

Traffic Center, A New, 9.

Troy Hill Road, 77.

Try Street Grade Crossing, 10.

Tunnel Routes, Areas Reached by High- and Low-Level, 54.

Twenty-eighth Street Grade Crossing, 57.

Twenty-second Street Bridge Approach--South Side, 86, 87.

Types of Thoroughfares, Special, 34-37.

Unified Procedure for City, County and Borough, 43, 44.

Washington Avenue Improvement, 82.

Washington Avenue Improvement East, 85.

Washington Road, 81.

Water Front, The, 19-28.

West Broadway Extension, 83.

West End Improvements, 80, 81.

Widening Old Streets, 37-43.

Width of Thoroughfares, 31-34.

Wilkinsburg-Edgewood Connection, 71, 72.

Wilkinsburg Grade Crossings, 71.

Wilkins Township Thoroughfares, 73, 74.

Wind Gap Road, 80.

Woodstock Avenue Extension, 73.

TRANSCRIBER'S NOTES

Silently corrected simple spelling, grammar, and typographical

errors.

Retained anachronistic and non-standard spellings as printed.

Enclosed italics markup in _underscores_.

Enclosed bold markup in =equals=.

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