Since 2022, the Iowa Department of Transportation (IDOT) has been conducting a ‘Super Two Corridor Study’ along portions of Highway 34, including a 65-mile stretch that runs through Clarke, Lucas and Monroe counties. The purpose of the study was to, “gain an understanding of the corridor’s ability to meet current and future travel and mobility needs and to identify any potential improvement projects that may help meet those future needs.”
A corridor study seeks to identify transportation issues and environmental concerns before construction funding is identified. The study aligns with strategies of improvement and areas of focus as defined in the IDOT’s State Transportation Plan: Iowa in Motion 2050, and can be used in future studies as a foundation along this part of the Highway 34 corridor, with modified information as needed.
A vision document was recently released by the IDOT, and included recommendations for new or improved intersection turn lane, new or improved turn lanes, new or improved passing lanes, new or improved climbing lanes, and spot improvement areas. These were determined by evaluating the existing Highway 34 corridor, including looking for deficiencies, evaluating intersection turn lanes, passing lane locations and future needs, and talking with community shareholders and gathering public input.
Proposed turn lane improvements
Across the three counties, the corridor study identified approximately 436 points of access to Highway 34, including 115 intersections. The study identified 17 locations for new right turn lanes, 11 for new left turn lanes, and three existing right turn lane upgrades to offset right turn lanes; an offset turn lane is a lane that shifts closer to oncoming traffic, that increases sight distance to improve left-turn safety.
In Clarke County, proposed locations for turning lanes are:
• County Road R16/135th Ave. - the westbound right turn lane is recommended to become an offset right turn lane.
• County Road R25/Lacelle Road/180th Ave. - two new right turn lanes and two new left turn lanes.
• 205th Ave. - new right turn lane
• Southwest Blvd. - convert the westbound turn lane to an offset left turn lane.
• Interstate 35 ramps - new right turn lanes at both the north and south bound ramps, as well as convert left turn lanes to offset left turn lanes.
• Warren Ave. - convert the left turn lanes to offset left turn lanes, and new right turn lanes in both directions.
• 270th Ave. - new right turn lane westbound
• R59/Liberty Hwy - new right and left turn lane.
All of the right and left-turn lanes are at paved intersections. All existing turn lanes west of R59/Liberty Highway to the Lucas County line are adequate.
Proposed passing and climbing lanes
The study found 14 locations for proposed passing lanes, seven going in each direction. Six existing climbing lanes were also recommended to be lengthened. A climbing lane is a lane that is used for short distances to help facilitate trucks or slow moving vehicles going up steep grades.
In Clarke County, the following locations were identified for passing and climbing lane improvements or installation:
• South and west of Murray, two westbound and one eastbound existing climbing lanes are recommended for extension. The westbound climbings lanes are those at Clarke/Union County line and 130th to 140th Ave. The eastbound climbing lane is the one from 110th to 130th Ave.
• West of Osceola near 160th Ave., one eastbound existing climbing lane to be extended, and a new westbound passing lane is recommended between Idaho Ave. and 205th Ave.
• East of Osceola, there are two eastbound and one westbound passing lanes recommended. One eastbound is from approximately Harken Hills to Idaho St., and the other is from about 288th Ave. to just east of 300th Ave. The westbound climbing lane is from midway between 270th and 288th Ave.s to 288th Ave.
Other passing and climbing lanes are adequate. The study looked at mainly rural areas, as Osceola has reduced speeds through towns and does not fit the need for passing lanes.
Typical passing lane concepts are separated passing lanes, adjoining passing lanes, overlapping passing lanes, and side-by-side passing lanes. The IDOT recommends separated passing lanes, with four to five miles between passing lanes. It is explained that uniform spacing allows a sense of expectation for drivers for when future passing opportunities will be.
Proposed spot improvements
There were many areas for spot improvements identified in both rural and urban areas along Highway 34, that would help drivers with clearer sightlines, improved visibility, create more consistent travel speed, navigation of roadways and side roads, as well as help Highway 34 recover from weather events by reducing maintenance needs. Improvements would include widening of road shoulders, snow fence or borrows, highway profile adjustments, guardrails, improved signage, ditch regrading and drainage improvements. Part of the improvements were taken into consideration for horse-drawn buggy traffic, including better signage and shoulders.
Some data included looking at the crash history along the study area of Highway 34. From 2017 to 2021, there were a total of 478 crashes, which included five fatal crashes and 54 serious or minor injury crashes; the rest were property damage. There were other crashes outside of the study area, or outside of the study window. The fatal crashes were not believed to be caused by roadway conditions.
Osceola has the highest existing travel volume, with 8,600 to 9,700 vehicles per day. The forecasted volume in 2048 will exceed 10,000, with ranges from 9,300 to 10,700.
Public involvement meetings
As part of the study, public input was gathered to gain ideas and comments regarding the development of the Highway 34 corridor study.
In August 2022, IDOT met with members of City of Osceola, Clarke County and City of Murray for small group meetings. The purpose of the meetings was to inform those in attendance about the study, and gather feedback on the current function of Highway 34 and future needs. At separate meetings in August of 2022, IDOT also met with Monroe and Lucas counties, and in early 2023 met with Clarke County’s Amish community and Lucas County Development Corporation. An in-person meeting was held in Nov. of 2022 in Chariton, as well as online.
At the Aug. 2022 meeting, areas or locations of concern noted by city and county officials included: Furnas Dr. and South Ridge Rd. where they cross with Highway 34 not having adequate space for vehicles turning south; blind spots for eastbound traffic when at South Ridge Rd. and Highway 34; fatalities and crashes at Southwest Blvd. and 34; difficulty for trucks turning at 34/69 intersection; near Murray, right turn and passing traffic at R15.
Attendees noted they would like any Highway 34 improvements to consider future growth and be proactive, including taking into account the E. Eddy Saylor Industrial Park, new housing developments, the growing Amish community, industrial growth, and the NEW Cooperative, Inc. rail loop increasing truck traffic.
Future public input meetings will be announced via IDOT’s website, study email distribution, advertisements and social media.
A copy of the US 34 Super Two Corridor Study - Vision Document March 2024 is available online at https://www.news.iowadot.gov/pim/. It continues further, detailed information about proposed changes, as well as diagrams and maps.
What is a Super-Two?
Editor’s Note: as previously appeared in the Creston News Advertiser.
In 2022, a letter from IDOT officials explained a Super-2 Highway,
“A Super-2 highway can include advanced design elements including wider paved shoulders, geometric improvements, left- and right-turn lanes, acceleration lanes, and climbing/passing lanes. This maximizes the benefits of two-lane roadways through improved safety, capacity, and mobility, while reinforcing the growing importance of lowering construction and maintenance costs. In other words, a Super-2 improvement can provide many of the benefits of a four-lane corridor without the excessive cost and impact on ag land acquisition.”
With support from county officials along its path, the state department of transportation will further research changes along sections of Highway 34 to improve traffic flow.
Iowa Director of Transportation Development Division in a letter to those counties stated the department responded from 2-year-old requests from many counties, including Union, to find ways to improve traffic flow on Highway 34 from Glenwood to Ottumwa.
“Back in 2020 you wrote to us to share your support for looking at Super-2 investments on US 34 between Glenwood and Ottumwa. Since that time, the Iowa Transportation Commission (Commission) and Iowa Department of Transportation (DOT) have undertaken several actions regarding the U.S. 34 corridor and we wanted to provide you an update,” according the letter.
“First, we commend your interest in Super-2 corridor improvements. A Super-2 highway can include advanced design elements including wider paved shoulders, geometric improvements, left- and right-turn lanes, acceleration lanes, and climbing/passing lanes. This maximizes the benefits of two-lane roadways through improved safety, capacity, and mobility, while reinforcing the growing importance of lowering construction and maintenance costs. In other words, a Super-2 improvement can provide many of the benefits of a four-lane corridor without the excessive cost and impact on ag land acquisition.”
The concept has two different dynamics.
“There are two separate processes for implementing Super-2 improvements. The first is by looking at planned pavement rehabilitation projects and assessing whether Super -2 design elements can be incorporated into the project. Through this process, the Commission has already awarded a project this fiscal year to resurface U.S. 34 from Albia to the Wapello County line that will convert two separate climbing lanes into longer passing lanes. The Commission will be considering adding an additional Super-2 project in fiscal year 2023 to resurface U.S. 34 between Lucas and Chariton that will include extending the eastbound climbing lane to turn it into a passing lane.”
Fiscal year 2023 is through June 30, 2023.
“The other process for identifying Super-2 projects is through corridor planning studies. Iowa DOT has initiated a planning study for the U.S. 34 corridor from Creston to Albia. We plan to begin another planning study that goes from Albia to Ottumwa later this year. The remaining corridor from Glenwood to Creston is on the list of candidate corridor planning studies for fiscal year 2023.”
The letter was signed by Linda Juckette, Chair, Iowa Transportation Commission; Richard Arnold, Vice-Chair, Iowa Transportation Commission and Scott Marler, Director, Iowa Department of Transportation.