Speed Limit and Safety Nexus Studies for Automated Enforcement Locations in the District of Columbia 4 Block 4th Street SW Study Area and Location District PSA Ward ANC Phase Description 27 6 6D Existing 4 Block 4 th Street Southwest Northbound Washington Monument Smithsonian Holocaust Museum Jefferson Memorial KEY: Existing Camera Proposed Camera Bus Stop Metro Station Hiker/Biker Trail School Other Pedestrian Generator This existing speed camera is located in Ward 6 at the 4 block of 4 th Street in the northbound direction. 4 th Street runs from Eastern Avenue Northwest in the north to the 4 th Street Bridge, where it becomes US to the south. The posted speed limit is 35 MPH. This camera was installed on May 22. W6-4 District Department of Transportation 55 M Street, SE, Suite 4 Washington, DC 23
4 Block 4th Street SW Field Assessment Summary 4 th Street is assumed to run in a North-South direction, and is classified as a principal arterial. 4 th Street has three through lanes and a right turn lane northbound and two through lanes and a through and left turn lane southbound. C Street has one left turn lane, one left or right turn lane, and one right turn lane westbound. This site has the following characteristics: The Holocaust Museum, Smithsonian Museum, Washington Monument and Jefferson Memorial are in this area. Rock Creek Park Trails are also nearby. The road has a concrete median on the north leg and a concrete barrier on the south leg. There are sidewalks with curb and gutter on both sides of all three legs of the intersection, a traffic signal and crosswalks with pedestrian signals on the north and east legs. The pavement is in good condition. Looking Northbound W6-42 District Department of Transportation 55 M Street, SE, Suite 4 Washington, DC 23
4 Block 4th Street SW Looking Southbound Speed Data Analysis Posted Speed Limit (MPH) 35 Mean Speed (MPH) 23 85th Percentile Speed (MPH) 29 MPH Pace Speed (MPH) 2-3 ADT 3,595 The mean speed is lower than the posted speed limit by 2 MPH and the 85 th percentile speed is lower than the posted speed by 6 MPH at this location. Crash Data Analysis From the Accident Summary Report provided for the dates between January, 2 and December 3, 22, there were a total of 48 crashes at this location. A breakdown of collision type can be found in the chart on the next page. The most common types of collision at this location were Rear End (2 crashes) and Side Swipes (2 crashes). The other collision types had three crashes or less each. Furthermore, this site experienced a high frequency (2 crashes) of injury-related crashes. W6-43 District Department of Transportation 55 M Street, SE, Suite 4 Washington, DC 23
4 Block 4th Street SW Severity Weather Surface condition Light Condition Total 48 Fatal 2.% Clear 35 72.9% Dry 38 79.2% Day 25 52.% Injury 2 25.% Rain 8 Wet 7 4.6% Night 2 4.7% Truck 8 Snow 2.% Snow/Ice 2.% Taxi 8 3 Number of Crashes by Collision Type 25 2 Number of Crashes 5 5 Right Angle Left Turn Right Turn Rear End Side Swipe Head On Parked Fixed Object Pedestrian Backing Unspecified Collision Type There was an elevated number of speed related crashes at this location, including side swipe and rear end crashes. The Highway Safety Manual lists assuming the lead driver will go through a green or yellow light, but the lead driver stops and changing lanes to avoid a slowing or stopped vehicle as two errors leading to side swipe and rear end crashes. Both of these errors can be decreased with a decrease in travel speed. The camera was installed on 5-7-22. The graph on the next page shows the number of crashes in three years prior to the speed camera s installation (42 crashes) and a year after the speed camera s installation (4 crashes). There was a decrease in the number of crashes after the installation of the camera. AASHTO Highway Safety Manual, st Edition, 2; Volume, page 2-3 W6-44 District Department of Transportation 55 M Street, SE, Suite 4 Washington, DC 23
4 Block 4th Street SW # Crashes by Year 2 9 8 7 6 4 2 8 6 4 2 6 Speed Camera Installed on 5/7/22 4 5/7/29-5/7/2 5/7/2-5/7/2 5/7/2-5/7/22 5/8/22-5/8/23 Safety Nexus This site presents the following safety considerations which may support the nexus between traffic safety and the speed camera:. Speed Data The speed data analysis shows travel speeds being lower than the posted speed limit. 2. Crash Data There was an elevated number of speed-related crashes at this location, including rear end and sideswipe collisions, as well as a high frequency (2 crashes) of injury-related crashes. There was a decrease in the number of crashes after the installation of the camera. 3. Field Assessment The following site characteristics suggest a need for a safer travel environment: a. The Smithsonian Museums, Holocaust Museum, Washington Monument, and Jefferson Memorial are in the area which generate pedestrian and bicycle activity. b. Rock Creek Park Trails are in the area which generate pedestrian and bicycle activity. c. There are multiple bus stops and one metro station which generate pedestrian activity. Although the speed data analysis showed the mean and 85th percentile speeds to be lower than the posted speed limit, but due to the elevated number of speed-related and injury-related crashes, the pedestrianinvolved crashes, the specific site characteristics, and pedestrian generators, there is a nexus between traffic safety and the speed camera at this location. W6-45 District Department of Transportation 55 M Street, SE, Suite 4 Washington, DC 23
4 block of 4th St SW NB Speed SAMMAT ENGINEERING SERVICES, LLC 55 RISING RIDGE ROAD MOUNT AIRY, MD 277 www.sammateng.com NB Start 6 2 26 3 36 4 46 5 56 6 66 7 76 Time 5 2 25 3 35 4 45 5 55 6 65 7 75 999 Total /9/3 * * * * * * * * * * * * * * * : * * * * * * * * * * * * * * * 2: 5 7 2 35 3: 5 3 29 76 4: 3 4 33 36 4 9 5: 8 8 58 24 3 2 6: 29 2 9 5 74 9 365 7: 32 9 44 235 9 8 58 8: 3 9 55 244 77 4 2 53 9: 34 5 49 23 65 9 54 : 27 6 39 276 86 7 54 : 3 94 286 633 2 PM 29 6 96 322 96 6 665 3: 32 7 65 344 3 7 4: 72 8 347 438 6 4 987 5: 85 32 438 45 97 4 6: 8 27 586 52 8 323 7: 84 76 526 37 42 4 23 8: 42 87 46 5 55 9: 7 5 432 344 49 3 95 2: 35 24 263 229 59 5 65 2: 4 9 298 246 54 3 66 22: 28 8 75 23 57 6 55 23: 23 42 5 37 4 367 Total 325 478 467 5247 352 27 7 354 W6-46
4 block of 4th St SW NB Speed SAMMAT ENGINEERING SERVICES, LLC 55 RISING RIDGE ROAD MOUNT AIRY, MD 277 www.sammateng.com NB Start 6 2 26 3 36 4 46 5 56 6 66 7 76 Time 5 2 25 3 35 4 45 5 55 6 65 7 75 999 Total /2/3 8 9 94 95 24 6 236 : 3 6 53 2 38 2: 5 3 3 24 4 67 3: * * * * * * * * * * * * * * * 4: * * * * * * * * * * * * * * * 5: * * * * * * * * * * * * * * * 6: * * * * * * * * * * * * * * * 7: * * * * * * * * * * * * * * * 8: * * * * * * * * * * * * * * * 9: * * * * * * * * * * * * * * * : * * * * * * * * * * * * * * * : * * * * * * * * * * * * * * * 2 PM * * * * * * * * * * * * * * * 3: * * * * * * * * * * * * * * * 4: * * * * * * * * * * * * * * * 5: * * * * * * * * * * * * * * * 6: * * * * * * * * * * * * * * * 7: * * * * * * * * * * * * * * * 8: * * * * * * * * * * * * * * * 9: * * * * * * * * * * * * * * * 2: * * * * * * * * * * * * * * * 2: * * * * * * * * * * * * * * * 22: * * * * * * * * * * * * * * * 23: * * * * * * * * * * * * * * * Total 6 22 85 72 38 8 44 Grand Total 34 5 482 549 39 35 7 3595 5th Percentile : 5th Percentile : 85th Percentile : 95th Percentile : 2 MPH 24 MPH 29 MPH 32 MPH Stats Mean Speed(Average) : 23 MPH MPH Pace Speed : 2-3 MPH Number in Pace : 844 Percent in Pace : 6.8% Number of Vehicles > 35 MPH : 268 Percent of Vehicles > 35 MPH : 2.% W6-47
4 block of 4th St SW NB Volume SAMMAT ENGINEERING SERVICES, LLC 55 RISING RIDGE ROAD MOUNT AIRY, MD 277 www.sammateng.com Start Tue 9-Nov-3 Wed 2-Nov-3 Thu 2-Nov-3 Daily Average Time A.M. P.M. A.M. P.M. A.M. P.M. A.M. P.M. 2: * 63 79 * * * 79 63 2:5 * 86 64 * * * 64 86 2:3 * 54 5 * * * 5 54 2:45 * 62 43 * * * 43 62 : * 63 3 * * * 3 63 :5 * 83 35 * * * 35 83 :3 * 73 33 * * * 33 73 :45 * 8 39 * * * 39 8 2: * 228 37 * * * 37 228 2:5 * 248 3 * * * 3 248 2:3 8 243 * * * * 8 243 2:45 7 268 * * * * 7 268 3: 3 26 * * * * 3 26 3:5 6 286 * * * * 6 286 3:3 9 273 * * * * 9 273 3:45 28 295 * * * * 28 295 4: 7 39 * * * * 7 39 4:5 9 338 * * * * 9 338 4:3 26 337 * * * * 26 337 4:45 29 329 * * * * 29 329 5: 3 34 * * * * 3 34 5:5 5 36 * * * * 5 36 5:3 6 342 * * * * 6 342 5:45 69 23 * * * * 69 23 6: 82 77 * * * * 82 77 6:5 82 34 * * * * 82 34 6:3 88 5 * * * * 88 5 6:45 3 34 * * * * 3 34 7: 27 3 * * * * 27 3 7:5 4 266 * * * * 4 266 7:3 33 99 * * * * 33 99 7:45 44 85 * * * * 44 85 8: 29 42 * * * * 29 42 8:5 39 57 * * * * 39 57 8:3 3 54 * * * * 3 54 8:45 33 62 * * * * 33 62 9: 9 7 * * * * 9 7 9:5 9 65 * * * * 9 65 9:3 38 86 * * * * 38 86 9:45 28 38 * * * * 28 38 : 36 3 * * * * 36 3 :5 28 6 * * * * 28 6 :3 39 32 * * * * 39 32 :45 38 37 * * * * 38 37 : 44 7 * * * * 44 7 :5 4 4 * * * * 4 4 :3 76 8 * * * * 76 8 :45 72 66 * * * * 72 66 Total 355 9649 44 3946 9649 Combined Total 354 44 3595 Peak : 4: 2: : 4: Vol. 633 323 236 633 323 P.H.F..899.979.747.899.979 ADT ADT 3,595 AADT 3,595 W6-48
DC Department of Transportation - Traffic Accident Reporting and Analysis System Accident Summary Report (R-8) Corridor: 4TH ST,NW,SW From D ST,SW TO C ST,SW Time Period Covered: From //2 To 2/3/22 Prepared By: Rahul Jain Prepared Date: 9/5/23 Total Number of Accident: Total Number of Fatalities: Total Number of Injuries: Total Number of Disabling Injuries: Total Number of NonDisabling Injuries: Total Number of Pedestrians Involved: Total Number of Bicycles Involved: Total Number of Motorcycles Involved: 48 9 5 2 Collision Type #ACC % Collision Type #ACC % Right Angle: 3 6.3% Fixed Object: 3 6.3% Left Turn: 2.% Ran Off Road: Right Turn: 2.% Ped. Involved: 2.% Rear End: 2 4.7% Backing: 2 4.2% Side Swiped: 2 25.% Non Collision: Head On: 2.% Under/Over Ride: Parked: 2.% Unspecified: 3 6.3% Time of Day #ACC % 7:3 ~ 9:3: 2.% 9:3 ~ :3: 4 8.3% :3 ~ 3:3: 5.4% 3:3 ~ 6:: 6 2.5% 6: ~8:3: 2.8% 8:3 ~ 7:3: 22 45.8% Unspecified: Day o fweek #ACC % Sunday: 8 Monday: 5.4% Tuesday: 7 4.6% Wednesday: 4 8.3% Thursday: 22.9% Friday: 5.4% Saturday: 8 Weather Condition #ACC % Clear: 35 72.9% Rain: 8 Snow: 2.% Sleet/Hail: Fog/Mist: 2.% Crosswind/Blowing Sand: Unspecified: 3 6.3% Surface Condition #ACC % Dry: 38 79.2% Wet: 7 4.6% Snow/Ice: 2.% Slush: Water/Sand: Repairing: Unspecified: 2 4.2% Type of Vehicle #VEH % Passenger Car: 59 65.6% Bus: 4 4.4% Truck: 8 8.9% Taxi: 8 8.9% Minivan: Police/Emergency Vehicle:.% Motorcycle/Moped: 2 2.2% Bicycle: Fixed Object: Unspecified: 8 8.9% Accident Severity Type #ACC % Fatal Collision: 2.% Injury Collision: 2 25.% PDO Collision: 35 72.9% Light Condition #ACC % Daylight: 25 52.% Dawn/Dusk: 2 4.2% Dark(Lighted): 2 4.7% Dark(Not Lighted): Dark(Unknown Lighting): Unspecified: 2.% Contributing Factor #VEH % Driver: Speed: 5 5.6% Driver: Alcohol/Drug:.% Driver: Electronic Device: Driver: Others: 22 24.4% Vehicle: Roadway:.% Unspecified: 6 67.8% Pedestrian Actions #ACC % In Crosswalk with Signal: In Crosswalk against Signal: In Crosswalk no Signal: In Unmarked Crosswalk: Not in Crosswalk: From Between Parked Cars: Unspecified: 28 Records are not approved as of 9/5/23 :27:58 AM W6-49
DC Department of Transportation - Traffic Accident Reporting and Analysis System Corridor: Time Period Covered: Accident Summary Report (R-8) 4TH ST,NW,SW From D ST,SW TO C ST,SW Total Number of Accident: Total Number of Fatalities: Total Number of Injuries: Total Number of Disabling Injuries: Total Number of NonDisabling Injuries: Total Number of Pedestrians Involved: Total Number of Bicycles Involved: Total Number of Motorcycles Involved: From 5/7/29 To 5/7/2 6 2 Prepared By: Rahul Jain Prepared Date: /8/2 3 Collision Type #ACC % Collision Type #ACC % Right Angle: Fixed Object: Left Turn: Ran Off Road: Right Turn: Ped. Involved: Rear End: 2 33.3% Backing: Side Swiped: 2 33.3% Non Collision: Head On: Under/Over Ride: Parked: Unspecified: Time of Day #ACC % 7:3 ~ 9:3: 9:3 ~ :3: :3 ~ 3:3: 3:3 ~ 6:: 6: ~8:3: 8:3 ~ 7:3: 4 66.7% Unspecified: Day o fweek #ACC % Sunday: Monday: Tuesday: 2 33.3% Wednesday: Thursday: Friday: Saturday: Weather Condition #ACC % Clear: 5 83.3% Rain: Snow: Sleet/Hail: Fog/Mist: Crosswind/Blowing Sand: Unspecified: Surface Condition #ACC % Dry: 6 Wet: Snow/Ice: Slush: Water/Sand: Repairing: Unspecified: Type of Vehicle #VEH % Passenger Car: 6 6 Bus: Truck: 2 2 Taxi: Minivan: Police/Emergency Vehicle: Motorcycle/Moped: Bicycle: Fixed Object: Unspecified: Accident Severity Type #ACC % Fatal Collision: Injury Collision: PDO Collision: 5 83.3% Light Condition #ACC % Daylight: Dawn/Dusk: Dark(Lighted): 5 83.3% Dark(Not Lighted): Dark(Unknown Lighting): Unspecified: Contributing Factor #VEH % Driver: Speed: Driver: Alcohol/Drug: Driver: Electronic Device: Driver: Others: 3 3 Vehicle: Roadway: Unspecified: 7 7 Pedestrian Actions #ACC % In Crosswalk with Signal: In Crosswalk against Signal: In Crosswalk no Signal: In Unmarked Crosswalk: Not in Crosswalk: From Between Parked Cars: Unspecified: Records are not approved as of /8/23 :4:7 AM W6-5
DC Department of Transportation - Traffic Accident Reporting and Analysis System Corridor: Time Period Covered: Accident Summary Report (R-8) 4TH ST,NW,SW From D ST,SW TO C ST,SW Total Number of Accident: Total Number of Fatalities: Total Number of Injuries: Total Number of Disabling Injuries: Total Number of NonDisabling Injuries: Total Number of Pedestrians Involved: Total Number of Bicycles Involved: Total Number of Motorcycles Involved: From 5/7/2 To 5/7/2 7 7 Prepared By: Rahul Jain Prepared Date: /8/2 3 Collision Type #ACC % Collision Type #ACC % Right Angle: 5.9% Fixed Object: Left Turn: Ran Off Road: Right Turn: 5.9% Ped. Involved: Rear End: 64.7% Backing: Side Swiped: 2.8% Non Collision: Head On: Under/Over Ride: Parked: 5.9% Unspecified: 5.9% Time of Day #ACC % 7:3 ~ 9:3: 9:3 ~ :3: 3 7.6% :3 ~ 3:3: 5.9% 3:3 ~ 6:: 6 3 6: ~8:3: 5.9% 8:3 ~ 7:3: 6 3 Unspecified: Day o fweek #ACC % Sunday: 2.8% Monday: 5.9% Tuesday: 4 23.5% Wednesday: 2.8% Thursday: 3 7.6% Friday: 2.8% Saturday: 3 7.6% Weather Condition #ACC % Clear: 4 82.4% Rain: 2.8% Snow: Sleet/Hail: Fog/Mist: Crosswind/Blowing Sand: Unspecified: 5.9% Surface Condition #ACC % Dry: 5 88.2% Wet: 2.8% Snow/Ice: Slush: Water/Sand: Repairing: Unspecified: Type of Vehicle #VEH % Passenger Car: 2 6 Bus: 2 5.7% Truck: 5 4.3% Taxi: 3 8.6% Minivan: Police/Emergency Vehicle: 2.9% Motorcycle/Moped: Bicycle: Fixed Object: Unspecified: 3 8.6% Accident Severity Type #ACC % Fatal Collision: Injury Collision: 6 3 PDO Collision: 64.7% Light Condition #ACC % Daylight: 3 76.5% Dawn/Dusk: Dark(Lighted): 4 23.5% Dark(Not Lighted): Dark(Unknown Lighting): Unspecified: Contributing Factor #VEH % Driver: Speed: 3 8.6% Driver: Alcohol/Drug: Driver: Electronic Device: Driver: Others: 4.4% Vehicle: Roadway: Unspecified: 28 8 Pedestrian Actions #ACC % In Crosswalk with Signal: In Crosswalk against Signal: In Crosswalk no Signal: In Unmarked Crosswalk: Not in Crosswalk: From Between Parked Cars: Unspecified: 7 Records are not approved as of /8/23 :: AM W6-5
DC Department of Transportation - Traffic Accident Reporting and Analysis System Corridor: Time Period Covered: Accident Summary Report (R-8) 4TH ST,NW,SW From D ST,SW TO C ST,SW Total Number of Accident: Total Number of Fatalities: Total Number of Injuries: Total Number of Disabling Injuries: Total Number of NonDisabling Injuries: Total Number of Pedestrians Involved: Total Number of Bicycles Involved: Total Number of Motorcycles Involved: From 5/7/2 To 5/7/22 9 3 Prepared By: Rahul Jain Prepared Date: /8/2 3 Collision Type #ACC % Collision Type #ACC % Right Angle: Fixed Object: 3 5.8% Left Turn: Ran Off Road: Right Turn: Ped. Involved: Rear End: 7 36.8% Backing: Side Swiped: 4 2.% Non Collision: Head On: Under/Over Ride: Parked: Unspecified: Time of Day #ACC % 7:3 ~ 9:3: 9:3 ~ :3: :3 ~ 3:3: 3 5.8% 3:3 ~ 6:: 6: ~8:3: 5 26.3% 8:3 ~ 7:3: 9 47.4% Unspecified: Day o fweek #ACC % Sunday: 3 5.8% Monday: 3 5.8% Tuesday: 2.5% Wednesday: Thursday: 5 26.3% Friday: 2.5% Saturday: 4 2.% Weather Condition #ACC % Clear: 2 63.2% Rain: 5 26.3% Snow: Sleet/Hail: Fog/Mist: Crosswind/Blowing Sand: Unspecified: Surface Condition #ACC % Dry: 3 68.4% Wet: 4 2.% Snow/Ice: Slush: Water/Sand: Repairing: Unspecified: Type of Vehicle #VEH % Passenger Car: 24 72.7% Bus: 2 6.% Truck: 2 6.% Taxi: 2 6.% Minivan: Police/Emergency Vehicle: Motorcycle/Moped: 3.% Bicycle: Fixed Object: Unspecified: 2 6.% Accident Severity Type #ACC % Fatal Collision: Injury Collision: 5 26.3% PDO Collision: 3 68.4% Light Condition #ACC % Daylight: 9 47.4% Dawn/Dusk: Dark(Lighted): 9 47.4% Dark(Not Lighted): Dark(Unknown Lighting): Unspecified: Contributing Factor #VEH % Driver: Speed: 3.% Driver: Alcohol/Drug: 3.% Driver: Electronic Device: Driver: Others: 3.3% Vehicle: Roadway: 3.% Unspecified: 2 6.6% Pedestrian Actions #ACC % In Crosswalk with Signal: In Crosswalk against Signal: In Crosswalk no Signal: In Unmarked Crosswalk: Not in Crosswalk: From Between Parked Cars: Unspecified: 2 Records are not approved as of /8/23 9:58:38 AM W6-52
DC Department of Transportation - Traffic Accident Reporting and Analysis System Corridor: Time Period Covered: Accident Summary Report (R-8) 4TH ST,NW,SW From D ST,SW TO C ST,SW Total Number of Accident: Total Number of Fatalities: Total Number of Injuries: Total Number of Disabling Injuries: Total Number of NonDisabling Injuries: Total Number of Pedestrians Involved: Total Number of Bicycles Involved: Total Number of Motorcycles Involved: From 5/8/22 To 5/8/23 4 5 Prepared By: Rahul Jain Prepared Date: /8/2 3 Collision Type #ACC % Collision Type #ACC % Right Angle: Fixed Object: Left Turn: Ran Off Road: Right Turn: Ped. Involved: Rear End: 3 2.4% Backing: Side Swiped: 6 42.9% Non Collision: Head On: Under/Over Ride: Parked: Unspecified: Time of Day #ACC % 7:3 ~ 9:3: 9:3 ~ :3: :3 ~ 3:3: 3:3 ~ 6:: 6: ~8:3: 3 2.4% 8:3 ~ 7:3: 8 5 Unspecified: Day o fweek #ACC % Sunday: 2 4.3% Monday: 4 28.6% Tuesday: Wednesday: Thursday: 4 28.6% Friday: Saturday: Weather Condition #ACC % Clear: 2 85.7% Rain: Snow: Sleet/Hail: Fog/Mist: Crosswind/Blowing Sand: Unspecified: Surface Condition #ACC % Dry: 2 85.7% Wet: Snow/Ice: Slush: Water/Sand: Repairing: Unspecified: Type of Vehicle #VEH % Passenger Car: 8 69.2% Bus: 3.8% Truck: 3.8% Taxi: 3.5% Minivan: Police/Emergency Vehicle: Motorcycle/Moped: 3.8% Bicycle: Fixed Object: Unspecified: 2 7.7% Accident Severity Type #ACC % Fatal Collision: Injury Collision: 4 28.6% PDO Collision: 7.4% Light Condition #ACC % Daylight: 5 35.7% Dawn/Dusk: Dark(Lighted): 7 5 Dark(Not Lighted): Dark(Unknown Lighting): Unspecified: Contributing Factor #VEH % Driver: Speed: 3.8% Driver: Alcohol/Drug: Driver: Electronic Device: Driver: Others: 8 3.8% Vehicle: Roadway: Unspecified: 7 65.4% Pedestrian Actions #ACC % In Crosswalk with Signal: In Crosswalk against Signal: In Crosswalk no Signal: In Unmarked Crosswalk: Not in Crosswalk: From Between Parked Cars: Unspecified: 9 Records are not approved as of /8/23 9:56:5 AM W6-53