Fall 2004
Alignments chosen for detailed study and consideration
The Federal Highway Administration (FHWA) has approved ACHD's recommendations for
which alignments to advance for detailed evaluation in the Environmental Impact
Statement (EIS). Pending the outcome of the study, one of these alignments or a
variation of the concept could become a future new crossing of the Boise River.
Click to download an image file of alignments map
[low res] |
[high res]
Download the
November Project Newsletter
The project team developed these recommendations based on requirements of the National
Environmental Policy Act (NEPA), public input and environmental and engineering
considerations. The first step in the process was to identify a range of alternatives
that would satisfy the projects Purpose and Need, the previously adopted statement
of what this study is to accomplish. Simply stated, the study is supposed to define
the location of a new Boise River crossing to link State Highway 44 (State Street)
with Chinden Boulevard (US 20/26) somewhere between Glenwood Street and Eagle Road.
Federal law requires consideration of alternatives including:
- No-Build;
- Transportation System Management (TSM) and Mass Transit; and
- Build Alternatives.
The No-Build Alternative assumes no new river crossing but assumes other planned
transportation improvements in the area. It provides a basis for comparing the pros
and cons of the Build Alternatives. Federal rules require that the No-Build Alternative
be advanced for detailed evaluation.
Transportation System Management (TSM) and Mass Transit will be evaluated as part
of the detailed environmental study, the EIS. TSM consists of ways to make traffic
flow smoother, such as optimizing signal timing or changes in lane configuration.
Mass transit considers actions such as providing bus, light rail or other transit
opportunities. Preliminary evaluations indicate that the TSM and Mass Transit alternatives
alone will not meet project Purpose and Need.
Build Alternatives were developed in several steps. An initial list of alternatives
was developed by the project team considering input from public meetings, agency
coordination, consultation with the project Technical and Community Advisory Committees
and recommendations from local officials. Each of the alternatives was evaluated
through an environmental screening process described below. Additional alternatives
were suggested during agency review of the draft screening report and these were
evaluated in the same manner as the initial alternatives. This process resulted
in recommendations on which Build Alternatives to advance for detailed study in
the EIS.
The project team used following criteria to evaluate alternatives:
1. Does the alignment meet project Purpose and Need? The following Purpose and Need
Statement was developed in consultation with Idaho Transportation Department and
the Federal Highway Administration:
The purpose of this project is to meet the future demand for traffic across the Boise
River and reduce congestion* on the river crossings by linking the intersection
of State Highway 55 and State Street to US 20/26 (Chinden Boulevard) between Glenwood
Street and Eagle Road.
(* FHWA has requested that reduce congestion be changed to a more quantitative
statement. A reduction in congestion may include reduction in volume to capacity
ratio, decrease in travel times, and/or improvement in level of service. Prior to
the draft EIS, reduce congestion will be replaced with more quantitative terms and
will be based on traffic forecast modeling.)
The project is needed to: 1) accommodate future demand for travel across the Boise
River and 2) relieve congestion due to future lack of capacity of the existing Eagle
Road and Glenwood Street Boise River crossing facilities.
2. How do the alignments impact each of the following resources?
- Cottonwood riparian area (important for wildlife habitat, wetlands and bald eagles);
- Historic sites that are or may be eligible for the National Register of Historic
Places;
- The 100-year floodplain;
- The Boise River floodway;
- Migratory birds, especially herons and cormorants that nest in the area; and
- Neighborhoods, farms, or businesses that the alignment passes through.
These six impact areas were chosen based on input from the public, agencies and
the projects advisory committees, and the magnitude of potential impacts. A
Preliminary Environmental Map and the 2003 Federal Emergency Management
Agency Floodplain Map were prepared using existing records and a windshield survey
of the project area. These maps were used to evaluate the environmental impacts
of the alignments. The project team also considered local transportation and land
use plans and the level of public interest in specific alternatives.
For the screening process, the project area was divided into northern and southern
sections, each with several possible alignments. In general, northern alignments
connect to State Street on the north and cross the Boise River. Southern alignments
begin south of the South Channel of the Boise River and connect to Chinden Boulevard
(US 20/26). The combination of a northern and one or more southern alignments results
in a single build alternative.
These alignments are recommended to be advanced for detailed study of their environmental
impacts.
Click to download JPEG file of alignments map
[low res] |
[high res]
Northern Alignments
- N5: SH-55/State to Center Crossing
- N6: SH-55/State to Center East Crossing
- N3: SH-55/State to West Middle with N3c: Northwest Connection (advance as part of
a split connection to Eagle Road and Chinden Boulevard)
Southern Alignments
- S2: Eagle and Chinden (advance with two connections, one to Eagle Road and one to
Chinden Boulevard)
- S4: Middle Cloverdale
- S7: Five Mile
- S10: Mountain View
The N5/N6 portion of the total alignment will be evaluated as a corridor. This approach
allows the project team to adjust the alignment to avoid or minimize impacts. The
alignments shown on the maps are not permanently set. They will be adjusted as necessary
to minimize impacts, while considering roadway and bridge engineering requirements.
The combination of north and south alignments results in thirteen possible Build
Alternatives, which include the possibility of one or two connections to Chinden
Boulevard or a split connection to Eagle Road and Chinden Boulevard.
The Federal Highway Administration approved ACHDs alignments recommendation in
September. The public process will continue early next year when the Study Team
brings forward an initial proposal for a preferred alignment at a series of public
meetings. The project is scheduled to be completed and an alignment chosen by early
2006.
Care to comment? Please use any of the options below.
By Mail to:
Sally Goodell
Ada County Highway District
3775 Adams St.
Garden City, ID 83714
By e-mail to:
threecities@achdidaho.org
You can also call ACHD at 387-6119.
Download the
November Project Newsletter
June Design Workshop Focused on "Fit and Feel" of Possible Bridge
Elected officials, technical staff and members of the general public gathered in
late June to discuss what a span could look like, what recreational amenities could
be targeted and what aesthetic aspects should be incorporated in any potential bridge
project. A
summary of those discussions is available. The design direction will guide
the project team as the detailed study moves ahead in coming months on the soon-to-be
chosen alignments for detailed analysis.
Look for Route Alignments for Further Study this Summer
The second public meeting for the Three Cities River Crossing drew more than 130
participants, who expressed their preferences on a number of potential road/bridge
alignments. The purpose of the April 21 meeting was to winnow the group of possible
(and some, less-than probable) routes to find the best ones for detailed analysis.
See meeting summary with maps of potential alignments. Study team members
will take the meeting materials and public input to upcoming meetings of the Three
Cities Citizens Advisory Committee and the Technical Committee for additional review
before making a recommendation about which routes should move forward for further
study.
The study team asked for help from the public in wading through the various alignments
proposed during the first Three Cities public meeting in February, finding the ones
that best fit the project's Purpose and Need as specified by law, blended well with
the environmental, cultural and neighborhood considerations, and met the projected
transportation needs.
NOTE: The high resolution files are quite large and recommended for broadband users
only, dial up users should select the low resolution version.
- Click to download JPEG file of alignments map
[low res] |
[high res]
- Click to download floodway map
[low res] |
[high res]
- Click to download environmental base map
[low res] |
[high res]
Under federal law, ACHD must evaluate a range of alignments for the proposed river
crossing. As a first step, we conducted a preliminary evaluation to consider the
following questions:
- Do the alignments meet the project's purpose and need and logical termini (rational
end points for a transportation improvement, and rational end point for review of
environmental impacts)?
- Which alignments avoid or minimize environmental impacts?
The approved purpose of this project is to meet the future demand for travel across
the Boise River and reduce congestion on the area river crossings by linking the
intersection of Highway 55 and State Street to Chinden Boulevard (U.S. 20/26) between
Glenwood Street and Eagle Road. The project need is two-fold: 1) Accommodate future
demand for travel across the river, and 2) Relieve congestion due to future lack
of capacity of the existing river crossings.
Proposed Logical Termini
- North: Intersection of Highway 55 and State Street
- South: Chinden Boulevard
Click Image for Larger View
Environmental law requires that we avoid or minimize impacts on:
- Threatened and endangered species (Bald Eagle)
- Wetlands
- Floodplain/floodway
- Historical and archaeological sites
- Parks
We also considered:
- Impact to migratory birds, like heron and cormorant rookeries
- Direct neighborhood, farm, or business impacts -- displacement, splitting neighborhoods,
removing homes and businesses
- Impacts to existing and proposed conservation easements
The maps were created through the use of:
- Biologists, who visited the area and noted the rookeries with heron and cormorant
activity.
- Aerial photos and field inspections were used to find Cottonwood riparian areas,
which include wetlands and help protect floodways, floodplains, water quality and
wildlife habitat, including Bald Eagles.
- A records review at the Idaho State Historic Preservation Office identified historic
sites.
- The 2003 Federal Emergency Management Agency flood maps indicated the floodways
and floodplain zones.
Each segment in the northern section on the map has been labeled with a number.
The numbers on the map correspond to numbers on the Matrix. The matrix has been
color coded so you can see the relative impacts of the alignment. Code:
Blue(low or no impact), yellow
(possible impacts) and red(high impacts).
Northern Alignment Maps and Evaluation Matrix:
Southern Alignment Maps and Evaluation Matrix:
The public comments, along with the conclusions of the advisory committees and study
team, will formulate a recommendation to the Federal Highway Administration (FHWA)
on which alignments should receive more detailed analysis. When FHWA makes a decision,
ACHD will send a newsletter to study participants. A preferred alignment is expected
to be chosen by the fall, at which time a third public meeting will be held to get
more public feedback.
April Meeting Summary
February Meeting Material:
The study got off to a good start on February 9th and 12th, when some 500 people
came to public meetings to express their wants, dislikes and observations about
a possible river crossing to connect State Street with Chinden Boulevard (U.S. 20/26).
The proposed roadway would be roughly at the midpoint between Glenwood Street and
Eagle Road, the area's existing north-south routes across the Boise River.
Feedback from the written comment sheets and small group sessions will be compiled
in advance of the next public meeting, and the results will be reported at the second
public meeting.
If you missed the February meetings or want to refresh your memory about the issues,
please see the links below.
Slide Show Presentation from February:
Slide 1
Slide 2
Slide 3
Slide 4
Slide 5
Slide 6
Slide 7
Slide 8
Slide 9
Slide 10
Care to comment? Please use any of the options below.
By Mail to:
Sally Goodell
Ada County Highway District
318 East 37th Street
Garden City, ID 83714
By e-mail to:
threecities@achd.ada.id.us