At least 295 persons were injured and one killed in traffic accidents last year at the District's top 10 "high hazard" intersections, according to statistics obtained from the D.C. department of highways and traffic.
The annual tabulation of "high hazard" accident locations, derived from police reports, is used to improve road and traffic conditions, according to Jack Hartley, director of the department of highways and traffic.
Traffic light modifications, lane expansions, road reroutings, medium installations and rumble strips (noise makers) are among the planned improvements for the 10 worst accidents spots, all located in the Northeast and Southeast sections of town.
"We try to systematize the traffic flow in these intersections and reduce the need for the motorist to make decisions," said Hartley. "Many accidents occur because the motorist has too many signs to read; too much confusion arises."
Hartley said that most of the city's accidents occurred in the Northeast and Southeast areas because there are no major throughways - such as Rock Creek Parkway or the Southwest Freeway - to keep traffic moving. "Traffic has to be on city streets in these areas. That causes the volume to be so high and increases exposure to accidents," Hartley said.
The formula used to determine the hazard locations is based on daily traffic volume through the intersections, the number of accidents, the number of injuries and fatalities, and the cost of the accidents. The estimated accident cost for the top 10 hazards locations was $1.5 million in 1976. This figure includes property damage, medical bills, days of work lost, or any other expense involved in a traffic accident.
"We get a pretty good picture of the trouble spots with this formula," said Hartley, "but sometimes one or two factors can throw it off. For example, several injuries at one accident location or even one fatally can bring a location to the top of the list."
In the last three years, at least five of the District's "high hazard" locations have reappeared at the top of the list. Hartley said this was because of the long procedure involved in making road improvements.
"From the inventory we take every year, a diagram is drawn up indicating exactly what the problem is. Out engineers then draw up a plan for improvement. After that costs are estimated and we take bids from contractors."
Under the 1973 Highway Safety Act, the District is eligible for federal funds for safety improvement construction. Last year the city spend $1.6 million on road modification.
According to the department of highways, the 10 high hazard intersections are:
Stanton Road and Suitland Parkway SE. This intersection was the scene of 40 accidents, 36 injuries and one fatality last year. The intersection sits at the bottom of a hill, making the speed and distance of cars difficult to judge. Most of the accidents have involved left turns because these is no left turn signal at the intersection. Hartley said the department considered banning turns off the Parkway, but did not because there would be no access to Stanton Road for several miles.
Safety improvement plans call for installation of a left turn lane and left turn signals. This project would take an estimated two years. The department also plans to install larger, overhead traffic lights.
Florida and New York Avenue NE. This crossing was the scene of 50 accidents, resulting in 34 injuries in 1976. The major cause of accidents here is the heavy flow of inbound traffic. Most of the accidents have been rear-end collisions. A majority of the accidents have occured in peak time and generally when the ground is wet.
Hartley said that despite major safety efforts over the past two years, the intersection has repeatedly shown up on the top 10 list.
So far the department has installed larger traffic signals and adjusted the synchronizations to allow for delayed green lights. Skid resistant pavements has been laid and left turns have been banned.Despite these efforts, there was one more accident at the intersection in 1976 than there was in 1975.
Bladensburg Road and New York Avenue NE.
In Hartley's opinion, this is the worst intersection on the list. "The road is very heavily traveled with multiple turns and a number of decisions the motorist has to make," said Hartley.
Most of the accidents occur in in the inbound lane. This, according to Hartley, is because it is the first traffic light on New York Avenue coming off Rte. 50 into the city.
It was the scene of 30 accidents (18 fewer than 1975) and 36 injuries last year. Sodium vapor (high intensity) street lights have been installed to improve lighting. Most turns have been banned and larger traffic lights have been installed. Overhead traffic lights will be installed. Hartley said they have done all they can here.
Minnesota and Pennsylvania Avenue and L'Enfant Square SE. This spot was the scene of 62 accidents and 31 injuries last year. There is no one cause of collisions here, according to Hartley. The intersection has 12 "traffic legs" or roadways converging at the intersection.
Inbound, high-speed traffic coming off the Anacostia Freeway ends up here, causing a great number of the collisions. Outbound, Hartley said, the motorist has too many decisions to make. A traffic island was installed last year to redirect traffic in a circle, thus eliminating some of the congestion.
Plans for the intersection include large overhead traffic lights and rechannelization of the roads and street paving.
Branch and Pennsylvania Avenue SE. Last year there were 31 accidents involving 32 injuries at this intersection. Most of the accidents were caused by wet pavement, poor visibility (it is on the top of a hill) and unbalanced lanes. It moved from No. 65 on the department's list last year to No. 5 this year. According to Hartley's this is a direct result of the increased number of accidents that have caused injuries.
The traffic department has laid skid resistant pavement and enlarged traffic signals. They have also moved the transition point of lane changing (during rush hours) back 100 yards to help prevent head-on collisions. Left turns from Pennsylvania onto Branch have been banned.
East Capitol Street Bridge. The number of accidents at the location has jumped from 18 to 32 in the past year. According to Hartley, most have been head-on collisions because there is no median. Also, the rough bridge surface has been the cause of several accidents.
Preliminary drawings have been devised by department engineers for major bridge reconstruction. The project would cost several million dollars and would include redecking the roadway and installing a median.
Anacostia Freeway and Howard Road, and Anacostia Freeway and 11th Streets. The half mile of roadway between the 11th Street ramp and the Howard Street exit on the Anacostia Freeway was the scene of 65 accidents and 45 injuries in 1976.
The major source of the problem is increased traffic flow on the freeway because of the South Capitol Street bridge construction. The traffic volume increases on the 11th Street ramp and within seconds the Howard Street exit is on top of the motorist, said Hartley. Most of the accidents have been rear-end collisions.
Safety improvements include the building of an additional lane between the ramp and the Howard Street exit. The half mile expansion will be completed in 18 to 24 months. Also, rumble strips (noise makers) will be installed to discourage motorists from changing lanes.
Montana, New York and West Virginia Avenues NE. This intersection was down from 80 accidents in 1975 to 53 last year, involving 24 injuries. It has traditionally been hihg on the department's "hazard" list. The intersection ha s10 points of conflict where accidents occur. The only changes the department has implemented involve installing several new and larger traffic lights.
N Street, New York Avenue and North Capitol Street. Accidents at this location have occurred in the inbound lane heading downtown. The intersection has been a "total surprise," Hartley said, because it has never been on the list before. There were 34 accidents and 26 injuries here last year. The department has not taken any safety precautions at the intersection yet.