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Mr. Fritts. Now I am going to show you a map prepared by the Virginia Department of Highways and shows the comparison of accidents on the Shirley Highway, a four-lane divided, limited access highway just south of Washington. Perhaps you have driven over it. Also, the parallel of U. S. 1, a four-lane undivided highway with no access control. This is an actual work diagram prepared by the department.

You will note that all accidents are shown by diagrams and symbols showing the location and type, and where one accident involves more than one injury it is indicated by numbers in the symbols.

The comparative accident records are shown by the summary. This is for the year 1953. The total number of accidents on Route 1 was 277. On the Shirley Highway, 100.

You will note also that the traffic volumes are approximately the same—10,000 on one, and a little more than 11,000 on the other. And the distances are about the same. In injury accidents there were 71 on Route 1 and 34 on Shirley; 142 people were injured on the old road, 67 on the new.

There were 10 fatalities on the old road and 3 on the new.

The computation has been made there and shows a reduction in the property damage, a comparison between the two. In the end the fatality rate on the old route was 20.5 per hundred million vehicle miles and on the Shirley Highway 6.1. That 6.1 resulted from 3 fatalities which is a pretty small statistical sample.

On the other hand last year the rate—the year before that the rate on the Shirley Highway was only 4.4.

Senator GORE. Highway 1 is a good road, is it not?

Mr. Fritts. That is an undivided uncontrolled access facility, down through all the developments south of Washington toward Richmond. It is undivided and it is one of the older normal service type of roads that we have existing in many sections.

Senator GORE. It is not a narrow highway.

Mr. FRITTS. No; it is not narrow, but the accident record shows that it is unsafe because it is serving so many purposes. It is serving all the property and all the businesses.

Senator GORE. Is Shirley
Mr. Fritts. It is a fully controlled access facility:
Senator GORE. But there are frequent access points?

Mr. Fritts. Oh, yes. We have several interchanges, indicated on the upper chart. There are several points of access, entrances, but they are all separated intersections.

I think the significance of this chart is just simply to make that comparison to show what happens when we actually build a new facility.

Now we will go to the next chart.
(The chart referred to appears on p. 823.)

Mr. Fritts. Here is a chart where we have gathered together the records on quite a sampling of the modern facilities as compared with the older facilities, just as we did with Shirley

In California, for instance, there is an excellent rate on the new modern freeways and expressways of 2.12 where on the whole rural State highway system the rate is 9.39.

In Maine we have an experience of 2.8 on the Maine Turnpike, and on old U. S. 1, for 1 year, it was 22.3.

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I might add that that rate on the old road has come down quite a bit since then but still the same ratio applies as applied on the other highways.

In Virginia we just mentioned the Shirley Highway.

In Connecticut we have quite a study for quite a period of time on the Merritt Parkway with 3.7; and on the old U. S. 1, 8.1.

In Kansas City, where they have a new expressway route in operation, they have not yet had a fatality; on a surface street that is parallel to it and serving large volumes they have 5.9.

In Michigan, the Detroit Industrial Expressway had a rate—this is 1953—of 6.7, whereas the parallel facility had 15.

I might add'in that case that there again it is a short section, relatively short. The rate for 1954 dropped down to 2.5 on that particular facility. So you have to average these things out over a period of time and over a long distance to get a stable sample.

In Michigan, Senator McNamara—this is information I just gotthe Detroit Expressway, the fatality rate is 3.0, and the major arterials in the city are 7.3.

In Pennsylvania, the Pennsylvania Turnpike this year, with improvement in enforcement and traffic control, has come down to 4.2.

The New York Throughway, since it has been in operation, has a record of 3.0.

Those examples illustrate what we mean by modern highway design compared with the accident picture on the old facilities. Based on that composite analysis of those several known situations we have made an estimate that if we were to complete just the Interstate System to those standards we could save some 3,500 lives a year, and that on an average 1 life can be saved for every 10 miles that we build to that standard.

Senator GORE. One life in what period ?

Mr. Fritts. One life per year for each 10 miles that we can put into service. In a 10-year period we would save somewhere in the vicinity of 35,000 lives or the equivalent of the number of deaths for 1 whole year on our entire highway system.

We do not have the data available to make the same kind of forecast or comparison for the entire road system network. But there is no longer any doubt that modern design features and adequate capacity can contribute importantly to safety on all roads. As our highways are improved substantial savings can be anticipated in life, limb, and property, along with the increased efficiency and economy of operation over the road as components of our transportation system.

Senator GORE. Let me ask you a question about the limitation of access. Do you attach more importance to the number of access points or the type of access points ?

Mr. Fritts. I think, sir, that it would be the type of access points. Obviously you cannot have too frequent access or you would always have irritation in your traffic stream. The idea of the controlled access facilities is to move traffic and at the same time provide access where it is reasonable and safe to do it. That means that you have to put your access points in frequently enough to provide a satisfactory service. Otherwise, you are defeating your purpose.

Senator GORE. I had planned to try to set up a schedule for the subcommittee to actually visualize the principal problems with which we are confronted. Of course Shirley Highway is easily available. I drive it fairly frequently. The access points on Shirley Highway are not too infrequent, it appears to me. There are many access points, but the entering traffic is fed in gradually and under conditions providing maximum safety. That caused me to inquire whether you would consider the number or the type of access points, the frequency or the type, more important.

Mr. FRITTS. I would think if we are going to do the job the way we should do it, we have to analyze our whole area movements when we determine the number of access points. We have to so locate our access points to serve the total area movement to the maximum. That means on some classes of highways the entrance would be much more direct than it would be on others.

Take in a suburban or even a metropolitan area, you obviously are going to bring your people in, take them in and off these facilities at a much more frequent rate than you would where there is no service requirement in a rural area where there is not any development. It depends on the amount of development that you have alongside a facility

I could not give you a specific formula for it but that is the way we would approach it. We would see what is the movement in the area, , what is the service demand, and suit our design to that.

Senator GORE. Would you suggest that Shirley Highway, and Highway 1, the examples you have taken of controlled access and noncontrolled access, of free access, would be about as good as we could find anywhere in the country!

Mr. Fritts. It is one of the good examples. I think it is one of the very good examples. For example, the Pennsylvania Turnpike is a toll road. On toll roads they do not put in as many access points as they do on the free roads because of the administrative expense of controlling the tolls—toll operation and administration. They hold it to a minimum but do not hold it down to a point where it will cut their revenues. They generate the maximum revenue against the operation of the toll road.

The free roads are more likely to give you more points of access than a toll facility and logically so. Once you get them in you have no cost of operation on them.

Senator GORE. Do you have any statistics to show the relationship between number of access points per mile and accidents ?

Mr. FRITTS. I do not believe, Senator, that we have reached the point yet where we can say that we have a bar which would show that if you had 5 access points per mile and over here we had only 3, that we have different accident rate. I do not know of any statistics that would show that.

Senator GORE. I wonder if you would be willing to look around and see if you can find such information?

Mr. FRITTS. I will be glad to look into that and report to you.

Senator GORE. We will leave a place right at this point in the record for a few days if you can locate such information.

Mr. Fritts. I will attempt to get the best information that I can. (The matter referred to is as follows:)


Washington, D. C., April 22, 1955. Hon. ALBERT GORE, Chairman, Subcommittee on Public Roads, Committee on Public Works,

United States Senate, Washington, D. C. DEAR SENATOR GORE: I am pleased to submit the following additional information on the relationship between highway design and accidents as requested in the hearing of April 1, 1955.

The statements and data contained herein pertain to the effect of highway intersections and their frequency on the accident rate, particularly on modern, fully controlled access facilities. The distance between interchanges is controlled basically by three factors:

1. The volume of traffic requiring entrance or exit from the various intersecting routes along the major artery and the type of adjacent development, such as agricultural, industrial, retail business or housing ;

2. The costs of construction for providing adequate highway separation structures and roadways; and

3. The minimum distance required for safe merging into or from the main traffic flow. The accident rate is affected primarily by the third of these major factors, the first two being matters of traffic service and economics.

Where large volumes of traffic are generated in built-up areas, a maximum number of interchange points are required and warranted. But between interchange points, ample distance must be provided for three types of driver-vehicle maneuvers.

First, for vehicles entering the major artery, an accelerating lane of about 1,000 feet is required to allow safe merging with traffic in the outer lane.

Second, for vehicles leaving the major artery sufficient distance must be provided to leave the main traffic stream at reasonably high speeds and enter a decelerating lane to slow down to a speed safe for a Jeparture on connecting facilities. This distance may also be 1,000 feet.

Third, in between the points of entrance and exit on multilane facilities, there also must be provided ample distance for vehicles to negotiate movements from inner lanes to outer lanes preparatory to exit without retarding other vehicles and to make the change safely.

All told, these requirements indicate that interchanges can be located at intervals as frequent as one per mile and still provide both safety and efficiency of movement. This frequency generally serves the pattern of major traffic movement in congested areas.

Experience on facilities existing in metropolitan areas such as Los Angeles, Boston, Chicago, Detroit, and elsewhere establishes the validity of these principles.

The experience thus far shows that the accident rate will remain low even though traffic service requires entrance and exit on the controlled access facility at frequent intervals. Service for facilities in between interchanges is provided on outer roadways or service roads for the short distances of travel to interchange points. Sincerely yours,


Vice President in Charge of Engineering. Senator GORE. The committee is very grateful to you for your appearance. You have been very helpful indeed.

This was your last chart?
Mr. FRITTS. Yes, sir.
Senator GORE. Thank you very much.
Mr. Fritts. Thank you, Mr. Chairman.

Senator GORE. The next witness is Mr. H. A. Thomson, secretary, Pennsylvania State Association of Township Supervisors, Upper Darby, Pa. He is also president of the national association.

We are glad to see you, Mr. Thomson.

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