(May 17, 2017) – Traditional "Large Lot Zoning" is "Greener" than "Smart Growth" within Urban Growth Boundaries . . . Copyright 2009 – 2017 . . . Tom Lane . . . Photographing California, Arizona, Nevada, New Mexico, Colorado, Utah, Oregon, and Seattle, Washington.
(Tom Lane, May 22, 2012) Is light rail (mass transit) the best solution for Seattle’s gridlock, when it will only reduce only 3% of all trips? Or, are more freeway lanes the best answer? How about more bike paths? Salt Lake City’s new Legacy Parkway combines more lanes and a bike path, and even includes protected wetland areas for wildlife.
Congestion on I-15 was reduced by 20% after the 15 mile parkway was completed in 2008. The Legacy Parkway is a “green” freeway, and representatives the future of highway construction in the country. It will be expanded northward, as discussed in this article in The Desert News. The Legacy Parkway could be used as a model for desperately needed new freeways in the Seattle area, as proposed by Dr. Bill Eager; click here for my post on Eager’s engineering plans for Seattle..
Salt Lake City and Seattle – Similar North-South Trending Freeway Systems
Both Salt Lake City and Seattle feature north-south trending freeways, with north-sound trending mountains constraining development on both sides of the cities. The Great Salt Lake and Utah Lake just west of Salt Lake City are analogous to Puget Sound just west of Seattle. Below, a view of Bountiful, Utah and the Great Salt Lake, looking west from a road near the Bountiful LDS (Mormon) Temple. If you zoom in, the north-trending Legacy Parkway is the furthest freeway to the west, before the wetlands and the Great Salt Lake:
The existing interstates in both cities (I-15 in Salt Lake City and I-5 in Seattle) have been widened to accommodate population growth. Loop freeways parallel to the interstates provide additional congestion relief in both cities – I-215 in Salt Lake City, and I-405 in Seattle.
Here’s a map of most of the Salt Lake City metro. A map of the Seattle metro appears several paragraphs below. Below, the arrow points to the 15 mile Legacy Parkway, parallel to I-15, and terminating at I-215. Click here for this same map in PDF format.
As population growth continues, additional parallel arterials are required to prevent the costs of widening interstate highways to ridiculous widths. While Salt Lake City and Seattle have numerous parallel arterials, both metros will continue to widen their existing freeways, and add more loop highways.
Currently, Salt Lake City is widening I-15 between Lehi and Spanish Fork, to meet the transportation needs through 2030: http://www.i15core.utah.gov/project_information.php
The Legacy Parkway and Preserve
The Legacy Parkway (SR-67) is a 4 lane freeway with four lanes parallel to I-15 between North Salt Lake and Farmington, north of I-215, and west of I-15, Bountiful, Centerville, and Woods Cross. The parkway features an adjacent bike path, nature preserve, and nature center.
The Legacy Parkway has reduced congestion on parallel route I-15 by 20%. From the UDOT web site –
“Interstate 15 through Davis County hosted upwards of 150,000 vehicles each day before the Legacy Parkway was completed.
Since the Parkway opened to traffic it is estimated that traffic on I-15, between the U.S. 89/Legacy Parkway/I-15 interchange in Farmington and the I-215 exit in North Salt Lake, has been consistently reduced as much as 20 percent.
Additionally, the Parkway provides a unique “escape route” from the Salt Lake City area northward, when accidents, construction, or other events significantly slows, or even closes I-15.”
Unique Features of the Parkway – The First of its Kind in the US
From the UDOT web site –
“A new western-style parkway: Legacy Parkway is the first of its kind in the United States and includes many unique elements:
Legacy Nature Preserve
From the Legacy Preserve web site
“The Legacy Nature Preserve is a 2,225-acre wildlife preserve on the southeastern shore of the Great Salt Lake. Established as environmental mitigation for the Legacy Parkway Project, the Preserve helps prevent encroachment of future development into this portion of the Great Salt Lake Ecosystem by restoring a mosaic of different wetland and upland habitats that are important for a myriad of wildlife species, especially migratory birds.”
The Legacy Parkway – Great Idea for Seattle’s SR-18 and the Snoqualmie Valley (I-605)
Currently, Seattle gridlock is intolerable on three clogged north-south parallel freeways – I-5, I-405, and SR-167. Originally, SR-18 was supposed to be widened to divert traffic from Tacoma (via Auburn) to I-90 near Snoqualmie. And, I-605 was supposed to be constructed from Snoqualmie north to Mill Creek. Right now, in some areas, SR-18 is only one or two lanes in each direction, with an intermittent divider, and resulting dangerous conditions for truckers going from Tacoma to Spokane.
Dr. Eager proposes making SR-18 a four lane divided highway, with additional climbing lanes in each direction towards the Tiger Mountain Summit. Currently, dangerous conditions exist at the summit, with an intermittent divider:
Dr. Eager proposes the new I-605 through the Snoqualmie Valley, from Snoqualmie to Mill Creek (parallel to the existing and congested SR-203. I-605 would serve as a parallel alternative to I-405, diverting travelers and truckers bound for Everett and Canada from entering Bellevue on I-405, and vice versa for those heading to eastern Washington and beyond.
I-605 would also reduce congestion during commute hours on SR-203 through Duvall, Fall City, and Snoqualmie. In fact, those who advocate “smart growth” should really favor I-605, given that the main road through the prestigious smart growth “Snoqualmie Ridge” development is used as a shortcut for commuters avoiding I-405. In addition, downtown Duvall has a smart growth towne center that is inaccessible during the afternoon commute –
Both SR-18 and SR-203 run through wetlands in the Green and Snoqualmie Valleys (similar to the Legacy parkway). Adjacent “country roads” function as popular bike routes, however, they often have no shoulders, and are clogged with traffic that should be running on the overdue freeways. Many of these roads now support small businesses for those stuck in gridlock, who don’t have access to a freeway for their commute:
Therefore, freeways similar to the “Legacy Parkway,” with adjacent bike paths and nature preserves in river wetlands, could be constructed as I-605 and SR-203. Imagine the popularity of a bike path extending from the Weyerhauser Headquarters in Federal Way, all the way through Auburn, then meeting existing trails in the Tiger Mountain State forest, then to trails in the Mountains to Sound Greenway along I-90, and finally through the Snoqualmie Valley.
Seattle can learn from the Legacy Parkway to complete Dr. Eager’s “End Gridlock Now” map. On the map below, SR-18, green, and I-605, dashed blue, are parallel freeways to I-5 and I-405, located to the far right on this map, nearly to the eastern edge of the metro (beyond most of the urban growth boundary). Click here for my post discussing Dr. Eager’s “End Gridlock Now.”
Similar Photos – Legacy Parkway and the Snoqualmie Valley
Note how these two photos are similar. The first is looking north on the Legacy Parkway, with the bike lane, horse farms, and distant mountains. The second is looking north, standing on the Duvall, Washington Urban Growth Boundary, looking down towards the existing two lane SR-203.
Imagine transforming the Snoqualmie Valley into a four lane freeway similar to the Legacy Parkway. This would take trucks off of I-405, with a bike path extending north to Mill Creek and south to the Tiger Mountain Summit and ultimately to the Weyerhauser Campus in Federal Way!
Imagine the popularity of this trail, and the possibility of bike races in a temperate climate. Imagine the congestion reduction on both I-5 and I-405, as travelers bound for Canada, Spokane, Boise, Tacoma, and even 800 miles to Salt Lake City, no longer have to use these narrow, congested Interstates.
Map of Dr. Eager’s “End Gridlok Now” for Metro Seattle
CLICK MAP to ENLARGE within your web browser – Dr. Bill Eager – “End Gridlock Now” –