Clark - NE 182nd Avenue/NE Risto Road
Project Number: 0623-01
From milepost 7.1 to milepost 7.98
RATA Funds: $1,200,000
Legislative District: 17
Status: PE and Design
Date Approved: 2023
1) Importance
The stop-controlled intersection of NE 182nd Avenue/NE Risto Road is located approximately 3 miles east of SR 503 and is an obsoleted old rural road. The roadways are both two lanes and their roadway classifications are Rural Minor Arterial. The truck classification for NE Risto Road, NE 182nd Avenue, and NE 199th Street is T-3. Roadway widths in the project area vary from 24 to 36 feet and shoulders are substandard, ranging between zero to two feet wide. Features are typical of older rural roads.
2) Deficiencies
This project begins at the northern end of the Salmon Creek Bridge (MP 7.10) and ends at NE 167th Avenue (MP 7.98). The intersection of NE Risto Road and NE 182nd Avenue is an old obsolete rural road intersection that was constructed when the Average Daily Traffic (ADT) was much lower than it is today, and design standards were less advanced. This increase in ADT has caused an increase in crashes and delay experienced by drivers. Other deficiencies include:
• A 180 feet (+/-) section of guardrail that does not meet current standards.
• The horizontal curve at NE Risto Road and NE 199th Street has limited sight distance due to overgrown vegetation and a narrow shoulder.
This horizontal curve also has a steep super-elevation where many drivers exceed the recommended speed.
• Pavement condition throughout the project shows signs of bleeding and raveling.
• In the last 3 years, the intersection of NE 182nd Avenue/Risto Road has experienced 14 crashes.
3) Improvements
The proposed improvements for the deficiencies described below will decrease crashes and improve sight distance to bring this section of roadway up to current design standards.
• The NE 182nd Avenue/Risto Road roundabout will replace a side street stop controlled intersection with a roundabout. This improvement will
enhance safety and reduce congestion, thereby improving system reliability and providing for safer freight movement. In the last 3 years,
the intersection of NE 182nd Avenue/Risto Road has experienced 14 crashes. Roundabouts are proven to reduce the instances of fatal
crashes by up to 90% while reducing delay and improving traffic flow.
• This project will improve the horizontal curve at NE Risto Road/NE 199th Street and will reduce the high number of crashes. As a
countermeasure, there will be vegetation trimming and textured pavement placed around the curve. The textured pavement will allow for a
higher friction coefficient than traditional asphalt and the vegetation trimming will improve sight distance on the inside of the horizontal
curve.
• Other safety enhancements around the NE Risto Road/NE 199th Street curve include an electronic speed feedback sign, raised pavement
markers, utility pole re-location, as well as shoulder and pavement widening to give drivers a better understanding of the roadway geometry
to negotiate the curve more safely.
• The substandard guardrail located on the west side of NE Risto Road in between the two horizontal curves will be brought to current
standards as well.
The stop-controlled intersection of NE 182nd Avenue/NE Risto Road is located approximately 3 miles east of SR 503 and is an obsoleted old rural road. The roadways are both two lanes and their roadway classifications are Rural Minor Arterial. The truck classification for NE Risto Road, NE 182nd Avenue, and NE 199th Street is T-3. Roadway widths in the project area vary from 24 to 36 feet and shoulders are substandard, ranging between zero to two feet wide. Features are typical of older rural roads.
2) Deficiencies
This project begins at the northern end of the Salmon Creek Bridge (MP 7.10) and ends at NE 167th Avenue (MP 7.98). The intersection of NE Risto Road and NE 182nd Avenue is an old obsolete rural road intersection that was constructed when the Average Daily Traffic (ADT) was much lower than it is today, and design standards were less advanced. This increase in ADT has caused an increase in crashes and delay experienced by drivers. Other deficiencies include:
• A 180 feet (+/-) section of guardrail that does not meet current standards.
• The horizontal curve at NE Risto Road and NE 199th Street has limited sight distance due to overgrown vegetation and a narrow shoulder.
This horizontal curve also has a steep super-elevation where many drivers exceed the recommended speed.
• Pavement condition throughout the project shows signs of bleeding and raveling.
• In the last 3 years, the intersection of NE 182nd Avenue/Risto Road has experienced 14 crashes.
3) Improvements
The proposed improvements for the deficiencies described below will decrease crashes and improve sight distance to bring this section of roadway up to current design standards.
• The NE 182nd Avenue/Risto Road roundabout will replace a side street stop controlled intersection with a roundabout. This improvement will
enhance safety and reduce congestion, thereby improving system reliability and providing for safer freight movement. In the last 3 years,
the intersection of NE 182nd Avenue/Risto Road has experienced 14 crashes. Roundabouts are proven to reduce the instances of fatal
crashes by up to 90% while reducing delay and improving traffic flow.
• This project will improve the horizontal curve at NE Risto Road/NE 199th Street and will reduce the high number of crashes. As a
countermeasure, there will be vegetation trimming and textured pavement placed around the curve. The textured pavement will allow for a
higher friction coefficient than traditional asphalt and the vegetation trimming will improve sight distance on the inside of the horizontal
curve.
• Other safety enhancements around the NE Risto Road/NE 199th Street curve include an electronic speed feedback sign, raised pavement
markers, utility pole re-location, as well as shoulder and pavement widening to give drivers a better understanding of the roadway geometry
to negotiate the curve more safely.
• The substandard guardrail located on the west side of NE Risto Road in between the two horizontal curves will be brought to current
standards as well.