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HomeMy WebLinkAboutOne-way Couplets.AnnaPowell.9.0CITY OF MERIDIAN PLANNING AND ZONING DEPARTMENT 660 E. WATERTOWER ROAD MERIDIAN, ID 83642 M E M O R A N D U M TO: MAYOR AND CITY COUNCIL MEMBERS FROM: ANNA BORCHERS POWELL, AICP PLANNING DIRECTOR DATE: JANUARY 20, 2022 RE: ONE-WAY COUPLETS I have reviewed approximately ten articles on the pros and cons of one-way couplets versus two-way streets. (Although the analysis is still useful, most of the articles actually deal with the issue of converting existing one-way couplets that were created in the 60s to two-way streets.) I have attached a diagram (Figure 7: Sample evaluation matrix) that best summarizes the analyses contained in those articles. I will briefly describe the issues below. Motorists Mobility. One way travel forces the driver to, at times, go “out of direction.” For example, instead of going directly north on Meridian Road, the driver may need to go north on Main, west on Pine, and then south on Meridian. Two-way streets provide better direct mobility. Vehicle Miles. For the same reason stated in the “Mobility” section, the vehicle miles traveled on a one-way couplet are 30% to 40% more than on a two- way street system. Turns. Again, please refer to the discussion on “Mobility.” A driver will potentially need to make 60% more turns to reach a destination on a one-way couplet. Travel Time (Through). A one-way street couplet is more effective at moving traffic through an area. Because of fewer turning conflicts, traffic is able to move at a very steady pace that is generally faster than could be achieved on a two- way street system. In the question of the Main/Meridian couplet, a question remains as to how the one-way couplet would function at intersection of Fairview/Cherry Lane. Traffic may back up at Main Street waiting for the light at Fairview; likewise, traffic may back up on Fairview waiting for the light at Meridian Road. Memo to Mayor and City Council Members on One-way Couplets Page 2 2 Travel Time (Local). The local travel time is better with the two-way street system because of the direct mobility afforded by such roads. Because motorists will need to go to Fairview/Cherry Lane or Washington to turnaround, the local travel time to properties between Washington and Cherry Lane will increase the most. Memo to Mayor and City Council Members on One-way Couplets Page 2 3 Capacity. Because of the smoother flow of traffic, a one-way couplet can accommodate between 2% to 5% more traffic than a two-way street system. Parking. There are different opinions as to which street configuration increases on-street parking. Because traffic is flowing in one direction on the couplets, the travel lanes can sometimes be narrowed enough to create angled parking along one or both sides of the roadway. This would obiviously increase the amount of on-street parking. However, the extra room is often used to create turn lanes, extra travel lanes, or bike lanes to increase the capacity of the roadway. Pedestrians. This is the one factor where I feel the diagram is inaccurate. The analysis appears unfairly critical of the one-way couplet system regarding pedestrian conflicts. It is true that the direction of cars is not as consistent on a one-way couplet system as it is on standard two-way streets. This is because of the many possible types of connections on a one-way couplet (e.g., one-way north to one-way west, one-way north to two-way east/west, one-way south to one-way east.) However, most pedestrians are in the habit of looking both ways before crossing the streets. If this habit continues, they will see the approaching cars. There is a second issue associated with pedestrian conflicts, which is the travel speed of the cars. Because cars will likely be traveling at higher speeds, pedestrians need to cross the street more quickly and, if there is an accident, the outcome is potentially more serious. Transit. The transit discussion addresses what happens in providing bus transit service. For example, a bus might go south on Meridian in the morning to take people to a park-and-ride lot, and then north on Main in the evening. Transit users would need to know both bus stop locations on both Meridian and Main. Retail. This factor considers how much of a store frontage is “eclipsed” on a one-way couplet system. Because traffic is only moving in one direction, drivers see 25% less of the store building than they would if there were two-way traffic. Neighborhoods. Most articles acknowledge that neighborhood access to an area is better with the two-way street system. Most would agree that the identity of an area is also improved with a two-way street system. Of all the factors considered above, this is probably the most difficult to quantify and the most debated. Proponents of the one-way couplets argue that the increased travel speed and capacity of the streets more than compensate for the inconvenience of the one-way grid and boost travel to the downtown areas and lead to greater economic growth, prosperity, and identity. Proponents for the two-way streets argue that the increased travel speed and capacity of the streets drives the Memo to Mayor and City Council Members on One-way Couplets Page 2 4 pedestrians out of the downtown areas leading to diminished ability to attract new stores and an “empty” downtown. Memo to Mayor and City Council Members on One-way Couplets Page 2 5 Other factors. Some additional factors for your consideration: Retail Sales. A couple of the articles stated that there was no appreciable increase or decrease of retail sales associated with converting an existing one- way couplet to two-way streets. Costs. One of the articles did point out that there are costs associated with changing the flow direction of streets. Such costs include striping for travel lanes and parking and installing new traffic directional signs. ACHD would be able to provide a better idea of anticipated costs. Type of Development. There is some question as to whether a one-way couplet may attract different types of businesses than would a two-way street system. If slower traffic speeds lead to a more “pedestrian friendly” atmosphere, the downtown may attract more businesses that cater to strolling or “window shopping” customers. Examples of such businesses might be boutiques, sit- down restaurants, ice-cream/soda shops, music and video stores, residences above offices, etc. These types of uses tend to stay open later in the evening and extend the downtown hours. Conversely, the one-way couplet may attract businesses that depend on door-to-door access, such as professional offices, medical offices, retail supply stores, copying and printing services, mailing and delivery services etc.