What is this project's purpose and need?
The purpose and need statement explains why MnDOT is undertaking a project and its objectives. The “need” identifies the transportation problems or deficiencies. The “purpose” is a broad statement of the primary intended transportation results of a proposed transportation improvement.
Phase 1 of Rethinking I-94 included efforts by MnDOT and its partners to identify issues to the regional freeway infrastructure, supporting local and regional transportation network, and investments supportive of reconnecting neighborhoods and revitalizing communities located along I-94 between downtown Minneapolis and Saint Paul. Building on the outreach efforts previously initiated with more detailed data, a clearer purpose emerged regarding transportation needs. Projects within the Rethinking I-94 program will accomplish the following:
- Improve asset conditions of I-94 bridges, pavement and supporting infrastructure (e.g., walls, drainage, etc.).
- Enhance safety for people and goods on, along, and across the I-94 corridor.
- Improve mobility for people and goods on, along, and across the I-94 corridor.
Transportation needs are split into two subcategories, primary needs and secondary needs. Primary needs are the main transportation problems (why MnDOT is proposing a program of projects). Secondary needs are other opportunities for improvement that should be addressed as part of the program of projects but are not the driving force behind the projects.
The subsurface on I-94 in the program area has not been replaced since the highway was built in the 1960s and is at the end of its useful life. To address these conditions, MnDOT resurfaces I-94 every seven years. MnDOT usually resurfaces freeways like I-94 every 13-17 years.
MnDOT has a robust system for monitoring, evaluating, rating, and reporting on bridges. Many of the bridges located on or over I-94 have problems. The primary source of data for bridge condition is the National Bridge Inventory (NBI) which is based on bridge inspections performed by trained individuals.
Measures that are used to indicate the condition of a bridge in the NBI include: deck, superstructure and substructure conditions. The scale ratings for each of these components are from 0 to 9, with 9 indicating excellent and 0 indicating failed condition. Bridges with a rating of 6-7 are classified as preventative maintenance (PM) or a major preservation (MP); and bridges with a rating of 5 or lower fall under the rehabilitation (rehab) or replacement categories. Thirty-eight of the 45 bridges within the program area currently have at least one of their key structural elements with a condition rating of 6 or below.
Retaining wall Condition
The condition of retaining walls is important to MnDOT. The function of a retaining wall is to hold soil in place. Should a retaining wall fail, the roadway could be impacted physically and operationally (traffic lanes on I-94 could become blocked). In addition, impacts could occur to adjacent properties. Retaining wall condition is divided into three basic components: main structure, foundation, and channel/channel protection. There are three walls in fair condition which suggests activities beyond ordinary maintenance are needed, and one wall in poor condition which suggests that the wall should be evaluated for rehabilitation or replacement.
I-94 has historically had a high number of crashes, with many being severe in nature. To better understand how good or bad a section of highway or intersection is in terms of safety, it is compared to other similar locations. A location that has a crash rate exceeding the critical crash rate is considered to have a safety problem. Calculated crash rates for program area segments range from 1.27 to 2.30 crashes per million vehicle miles traveled. These rates exceed the critical crash rates that range from 1.01 to 1.04 crashes per million vehicle miles traveled. The crash data was also reviewed in terms of severity. Within the program area 79 percent (1,721) of the crashes are property damage only crashes. Fatal crashes (3) account for less than 1 percent of the crashes and injury crashes account for slightly over 20 percent (446) of the crashes. Interchanges within the program area generally do not experience crash rates above the critical crash rate. The only interchange that has a crash rate above the critical crash rate is the I-94 interchange with I-35W/Hwy 55. Crashes at this location may have been influenced by construction on I-35.
Mobility, the ability of a person or people to travel from one place to another, on I-94 within the program area is considered deficient. Problems include: poor level of service (LOS), multiple hours of congestion, reduced travel speeds, increases in vehicle delay and poor travel time reliability.
- Poor level of service: LOS is represented on a scale of LOS A (free-flow) to LOS F (congested). Many areas experience LOS F during the morning and afternoon peak periods. In general, westbound I-94 has poor LOS during both the morning and afternoon periods. Eastbound I-94 has poor LOS during the afternoon period. LOS E-F conditions can extend for 2-4 hours at various locations.
- Multiple hours of congestion: Congestion affects all traffic. Cars, freight, and transit vehicles in travel lanes are impacted directly, and the speed of transit vehicles in bus shoulder lanes (where available) is limited by the speed of adjacent traffic. There generally is more congestion during the morning period for westbound traffic and in the afternoon period for eastbound traffic.
- Reduced travel speeds: In general, the slowest vehicle speeds in the program area are recorded during the afternoon peak period in both eastbound and westbound directions. Three locations create bottlenecks which impact vehicle speed in both directions: the Lowry Hill Tunnel (west of western program limits); Hwy 280; and Snelling Avenue. This trend was also recognized for buses along I-94.
- Increases in vehicle delay: Total vehicle delay is the difference between the congested travel time for vehicles and the travel time at posted speeds. Person delay is similar to vehicle delay, but it incorporates vehicle occupancy to describe delay experienced by all travelers. I-94 experiences high levels of vehicle and person delay. This delay is expected to increase in the future.
- Poor travel time reliability: Travel time reliability is “the consistency or dependability in travel times, as measured from day-to-day and/or across different times of day.” Planning Time Index (PTI) provides a simple measure of reliability. A PTI value of 2 means that for a trip that takes 30 minutes in uncongested conditions, a traveler should allow 60 minutes during periods of congestion. PTI for eastbound I-94 ranges from 1.09–1.19 in the morning peak and 2.98–3.26 in the afternoon. PTI for westbound I-94 in the program area ranges from 1.81–2.16 in the morning peak and 1.26–3.91 in the afternoon.
Walkability and Bikeability
The construction of I-94 severed a regularly spaced grid of local streets through neighborhoods and replaced it with fewer streets that cross the freeway with more traffic. Despite the reduction in local streets, the existing and planned pedestrian and bicycle network within the I-94 corridor is fairly extensive. There are opportunities to cross the corridor on roads and standalone pedestrian facilities under the jurisdiction of cities, counties and MnDOT. Local agencies have begun installing dedicated bicycle facilities across I-94 in recent years as part of a regional bikeway system. Additionally, pedestrians and bicyclists use facilities that parallel I-94 to reach key origins and destinations on both sides of the corridor. Beyond the existing facilities, there are several bicycle and pedestrian improvements planned along and across the I-94 corridor. However, existing walking and biking facilities are not consistently designed and are considered substandard throughout much of the corridor. Improving opportunities for pedestrians and bicyclists to cross I-94 was a common theme identified by residents during the Rethinking I-94 Phase 1 study engagement process. To better understand how design inconsistencies and conditions relating to comfort and safety impact users, a multimodal level of service (MMLOS) system was used to evaluate and rate pedestrian and bicycle facilities. A MMLOS D or worse indicates improvements should be considered.
Safety on Intersecting Streets
This section addresses the streets that have access to I-94. On the intersecting streets the crashes include motor vehicles, pedestrians, bicyclists and alternate mode (scooter, etc.) travelers.
Fourteen of the segments on intersecting streets have crash rates higher than critical crash rates. Many of the segments have crash rates well above the critical crash rate. For example, Cedar Avenue has a crash rate of 22.07 which is over three and a half times the critical crash rate. Cross street segments with crash rates multiple times the critical crash rate include I-35W/TH 55, Cedar Avenue, 25th Avenue, Riverside Avenue, Huron Boulevard, Hamline Avenue, and Lexington Avenue.
Recognizing that non-motorized users (pedestrians, bicyclists, etc.) are present on intersecting roadways, the segments with crash rates above the critical rates were further reviewed to understand if the crashes included non-motorized users. Cross streets that have segments with crash rates that are higher than the critical crash rates and have pedestrian and/or bicycle crashes accounting for over 10 percent of the crashes include Cedar Ave., Huron Blvd., Snelling Ave., Hamline Ave., and Dale St.
Drainage Infrastructure Condition
Generally, stormwater infrastructure is expected to have a service life of 100 years. Approximately 10 percent of the structures and 5 percent of the pipes have no remaining life today, and approximately 46 percent of the structures and 51 percent of the pipes will be nearing the end of their life in 2040.
Since the I-94 corridor is depressed below adjacent land uses, there is a higher potential for stormwater capacity constraints and flooding. Within the program area there are five tunnels that the I-94 drainage system connects into. All five of the tunnels are undersized (defined as a 10-year water level that exceeds the top of the pipe). They cannot convey the runoff from the storm while maintaining gravity flow conditions. Almost all the trunk storm sewer pipes along I-94 in the project area are under capacity. Because the tunnels are generally deep, this does not necessarily lead to flooding conditions. However, one area shows standing water on the pavement when modeled.
Noise Wall Condition
Most of the noise walls are in good or excellent condition. Two walls are in fair condition. It is anticipated that the noise wall condition will worsen. It is anticipated that in the future, four walls will be in fair condition.
There are four additional considerations that influence the program development process and alternatives evaluation.
- Consistency with State and Regional Plans: This includes the MnDOT 20-Year State Highway Investment Plan, Metropolitan Council 2040 Transportation Policy Plan, and MnDOT Metro District Bicycle Plan.
- Geometric Deficiencies – Vertical Clearance Consistency: This refers to the inconsistent height underneath bridges and its effect on the movement of freight through the corridor.
- Recent Projects in the Area (2015-2019): This includes projects in and near the program area completed by MnDOT and other agencies.
- Future Projects in the Area: This includes projects in and near the program area with dedicated funding within the next five years.