chapter 4. comparison of alternatives - sellwood bridge · additional investment would ... and the...

Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement 4 -1

Chapter 3 presented an evaluation of the environmental consequences of the No Build Alternative and the Build alternatives for social and natural environmental disciplines. Based on these fi ndings and input from the public and project groups throughout the project’s planning process, the project team developed key differentiators to help the public and decision-makers understand the differences between alternatives. This chapter compares alternatives by identifying key items that distinguish the following:

• No Build Alternative versus Build alternatives. No Build Alternative impacts and impacts common to all Build alternatives.

• Among Build alternatives. Impacts unique to individual Build alternatives.

• Among elements of the Build alternatives. Elements of the Build alternatives include alignment, west-side interchange type, basic bridge cross-section, SE 6th Avenue intersection—neighborhood cut-through traffi c versus traffi c operations, and rehabilitation versus replacement.

4.1 Key Differentiators between the No Build Alternative and the Build Alternatives

The following subsections describe the key differentiators between the No Build Alternative and all of the Build alternatives:

• Structural integrity and motorized vehicle safety• OR 43 traffi c fl ow• Transit and freight use• Bicyclist and pedestrian use• Visual impacts

4.1.1 Structural Integrity and Motorized Vehicle Safety

The existing bridge has inadequate structural integrity. It cannot safely accommodate various vehicle types (including transit vehicles, trucks, and emergency vehicles) and cannot withstand moderate seismic events. In addition, the roadway design for the bridge and the west-side interchange with OR 43 is substandard and unsafe.

The Build alternatives would provide structural and safety improvements by:

• Eliminating the existing 10-ton weight limit. This would allow trucks, buses, and emergency vehicles to cross the bridge. The No Build Alternative would maintain the existing 10-ton weight limit and restrict trucks, buses, and emergency vehicles from using the bridge.

• Improving the existing geometric defi ciencies of the interchange with OR 43. This would upgrade the interchange to meet existing roadway design standards, which would improve safety for automobiles and emergency, transit, and freight vehicles. The No Build Alternative would not improve existing geometric defi ciencies.

• Retrofi tting or upgrading the bridge to existing seismic standards. This would improve the ability of the rehabilitated or replaced bridge to withstand a seismic event. The No Build Alternative would not retrofi t the bridge to existing seismic standards.

• Providing a 75-year design life. The No Build Alternative would provide only a 20-year design life. Additional investment would be required to continue use of the bridge beyond the 20-year period.

Chapter 4 . Compar ison of Al ternat ives

4 -2 Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement

Key D i f fe rent ia to rs bet ween the No Bu i ld Al te rnat ive and the Bu i ld Al te rnat ives Chapte r 4 : Compar i son o f A l te rnat ives

All the bus routes serving the study area would continue to operate, and the two bus lines that were discontinued when weight-limit restrictions were placed on the bridge would be reinstated. The reintroduction of the bus routes would result in a slight mode shift from automobile trips to transit because of increased transit accessibility to Sellwood residents. This would result in a lower percentage of automobile trips across the bridge under the Build alternatives than under the No Build Alternative.

Currently, trucks of more than 10 tons that would normally use the Sellwood Bridge must travel out-of-direction to other bridge crossings, such as the Ross Island Bridge and the I-205 Abernethy Bridge. This truck detour would be removed in all the Build alternatives, resulting in more direct routes for freight to and from their destinations in the Sellwood area.

Table 4.1-3 summarizes transit and freight use questions between the No Build Alternative and the Build alternatives.

4.1.4 Bicyclist and Pedestrian Use Under the No Build Alternative, the facilities would remain the same, which would continue to challenge bicyclist and pedestrian travel across the bridge. All Build alternatives would improve bicyclist and pedestrian conditions compared to the No Build Alternative, and would therefore increase bicyclist and pedestrian use across the bridge.

Table 4.1-4 summarizes bicyclist and pedestrian use between the No Build Alternative and the Build alternatives. The analysis identifi ed impacts of the different bicycle and pedestrian facilities among the Build alternatives.

4.1.5 Visual Impacts The three types of west-side interchanges proposed under the Build alternatives (roundabout, trumpet, and single-point signalized) would signifi cantly change the landscape west of the river. Although mitigation measures could mediate the visual

Table 4.1-1 summarizes the structural integrity and safety elements between the No Build Alternative and the Build alternatives.

4.1.2 OR 43 Traffi c Flow Traffi c traveling to the Sellwood Bridge currently affects mobility on OR 43. A short ramp from OR 43 northbound and no ramp from OR 43 southbound cause vehicles to back up onto OR 43. This situation affects traffi c traveling between Portland and Lake Oswego. The existing signalized intersection south of the bridge on OR 43 also causes traffi c back ups. The Build alternatives would improve OR 43 traffi c fl ow by:

• Providing free-fl ow north/south movement on OR 43 through the bottom level of a new interchange. The No Build Alternative would not allow free-fl ow traffi c movement because it would maintain the existing signalized intersection on the south side of the existing OR 43/Sellwood Bridge interchange.

• Increasing the vehicle storage area to reduce back ups. The new interchange would provide ramps to the Sellwood Bridge from OR 43. During the peak periods, vehicles traveling to the Sellwood Bridge would back up on these ramps rather than on OR 43, reducing backups on OR 43. The No Build Alternative would maintain existing conditions—that is, Sellwood Bridge traffi c would continue to force vehicles to back up onto OR 43, impeding north/south traffi c.

Table 4.1-2 summarizes OR 43 traffi c fl ow between the No Build Alternative and the Build alternatives.

4.1.3 Transit and Freight Use The existing bridge cannot safely accommodate transit and freight vehicles because it has inadequate structural integrity. The Build alternatives would eliminate the 10-ton weight restriction on the Sellwood Bridge. Transit and freight vehicles would be allowed on the bridge.



ElementNo Build

AlternativeBuild

AlternativesAllow trucks, transit vehicles, and emergency vehicles to use the bridge? No YesImprove safety for motorists at the OR 43 interchange? No YesImprove the bridge’s ability to withstand a seismic event? No YesExtend the bridge’s design life? Yes, for 20 years Yes, for 75 years

Table 4.1-1. Structural Integrity and Safety by No Build Alternative and Build Alternatives.

ElementNo Build

AlternativeBuild

AlternativesImproves bicyclist and pedestrian facilities? No YesProjected daily bicyclist and pedestrian usage in 2035 (weekday) 1,970 9,350Projected daily bicyclist and pedestrian usage in 2035 (weekend) 3,020 14,350

Table 4.1-4. Bicyclist and Pedestrian Use by No Build Alternative and Build Alternatives.

impacts from retaining walls and rock face cuts, the Build alternatives would still cause signifi cant negative visual impacts from tree loss, rock face cuts, and retaining walls above the southbound ramps of the interchanges.

To construct the interchange, the hillside above OR 43 would be cut and vegetation would be removed. These activities would have signifi cant adverse impacts to the visual environment. New structures on the west riverbank would include retaining walls and elevated ramps on bridges.

New retaining walls at least 20 feet higher than the proposed southbound ramps would be exposed. The views from Sellwood toward the West Hills across the Willamette River would be the most strongly impacted by hillside cuts and retaining walls. The views of those traveling on OR 43also would be highly impacted with any of the Build alternatives.

Figure 4.1-1 illustrates the existing view of the west side from the bridge. The west-side landscape would be the same under the No Build Alternative.

ElementNo Build

AlternativeBuild

AlternativesProvides north-south free-fl ow mobilityon OR 43 without a signalized intersection? No Yes

Reduces back ups on OR 43, especiallyduring the afternoon/evening peak period? No Yes

Provides additional storage area forvehicles traveling to the Sellwood Bridge? No Yes

Table 4.1-2. OR 43 Traffi c Flow by No Build Alternative and Build Alternatives.

ElementNo Build

AlternativeBuild

AlternativesAllow buses to cross the bridge? No YesReinstate two bus lines across the bridge? No YesAllow trucks of more than 10 tons to cross the bridge? No YesReduce out-of-direction travel for freight and transit vehicles? No Yes

Table 4.1-3. Transit and Freight Use Questions by No Build Alternative and Build Alternatives.

4 - 4 Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement


Figure 4.1-1. West-side View.

Existing Condition and No Build Alternative

Build Alternative—Alternative A

Build Alternative—Alternative C

Build Alternative—Alternative E


Key D i f fe rent ia to rs among Bu i ld Al te rnat ives Chapte r 4 : Compar i son o f A l te rnat ives

• Businesses. Regional businesses would be affected by increased travel times for their customers and suppliers. Businesses on SE Tacoma Street and within a few blocks of SE Tacoma Street between SE 6th Avenue and SE 17th Avenue would have reduced access during the closure period. Reduced access would translate to lower sales and loss of owner and labor income, all else being equal. Total annual owner income losses for businesses in this area are estimated to range from $782,000 to $2,018,000, about 9 percent to 22 percent of total business income in that area. Total annual labor income losses within the same area are estimated to range from $1.1 million to $2.8 million, about 5 percent to 13 percent of total labor income in that area. Businesses located on SE Tacoma Street would be expected to experience more negative impacts than those on side streets.

• All bridge users. All existing bridge users would have increased travel times and more circuitous routes because of detours. Impacts to pedestrians, for whom several miles of out-of direction travel to other bridges might make walking trips infeasible, would incur the most substantial impacts. Bicyclists would also incur substantial increases in travel times.

• Transportation system users. Out-of-direction travel for Sellwood Bridge users would also affect other users of the transportation system. Rerouting of peak hour Sellwood Bridge trips to other, already congested, facilities would increase travel times and costs for all users of those facilities. Travel model results estimate additional morning and afternoon weekday peak hour vehicle hours of delay caused by the Sellwood Bridge closure during construction. These delays would result in travel time and vehicle operating cost increases for Sellwood Bridge users and other drivers ranging from $63.3 million to $110.8 million for Alternatives A, B (without the temporary detour bridge), and C.

Figure 4.1-1 also provides visual simulations for Alternatives A, C, and E. These simulations illustrate cuts and retaining walls into the west-side hillside. Simulations of the west-side hillside are not available for Alternatives B and D.

4.2 Key Differentiators among Build Alternatives

The following subsections describe the key differentiators among Build alternatives:

• Bridge closure

• Construction cost

• Ability to phase construction

• Bicyclists and pedestrians

• Transit

• Residential displacements

• Business displacements

• Maintenance of access to businessesand residences

• Park and recreational facility impacts

• Section 4(f)

• Regulated fl oodway

4.2.1 Bridge Closure Alternatives A, B (without temporary detour bridge), and C would require bridge closure during most of the construction period, resulting in signifi cant negative impacts. These impacts vary by the length of bridge closure. Although the No Build Alternative would result in bridge closure for 6 to 8 months for maintenance activities, closure periods for the Build Alternatives would be much longer and would be expected to have more severe economic impacts. The largest losses to business income could be expected under Alternative C because of the longer construction period (42 months) compared to Alternatives A and B without temporary detour bridge (24 months each).

Major negative impacts related to bridge closure include the following:



Figure 4.2-3 shows the estimated interchange construction cost for each alternative in year 2012 dollars. The west-side interchange construction costs for the Build alternatives would range between $88 million and $102 million.

Figure 4.2-4 shows the estimated east-side connection construction cost for each alternative in year 2012 dollars. The east-side connection construction costs for the Build alternatives would range between $1.6 million and $5.4 million.

4.2.3 Ability to Phase Construction This Draft Environmental Impact Statement (DEIS) considers each Build alternative as a complete packaged project. However, funding sources for any of the Build alternatives are uncertain at this time. If available funding were less than the full project cost, the project could be phased to construct various portions at different times during a 20-year timeframe. The bridge could be rehabilitated or newly constructed in a fi rst phase and the west-side interchange could be constructed in a second phase.

As shown on Figure 4.2-5, Alternatives A, B, C, and D would rehabilitate or construct a new bridge on the existing alignment. Therefore, if suffi cient funding were not available to construct both the bridge and the interchange elements at the same

Table 4.2-1 summarizes information about whether the bridge would be closed and, if closed, the duration, business loss, and commuter cost.

4.2.2 Construction Cost Construction cost estimates were prepared for the Build alternatives. These estimates, which are based on conceptual design-level data, provide a basis for cost comparisons between alternatives. More detailed cost data will be available following the preliminary design of the preferred alternative.

Figure 4.2-1 shows the total estimated construction cost for each alternative in year 2012 dollars. (Year 2012 is the assumed midpoint of construction.) The construction costs for the Build alternatives would range between $280 million and $361 million.

Figures 4.2-2, 4.2-3, and 4.2-4 summarize the construction costs for three elements of the Build alternatives: bridge, west-side interchange, and east-side connection.

Figure 4.2-2 shows the estimated bridge construction cost for each alternative in year 2012 dollars. The bridge construction costs for the Build alternatives would range between $185 million and $269 million.

AlternativeBridge

Closure?If Closed,

Duration of Closure

Business Loss during

Closurea

Commuter Cost during

Closureb

A Yes24 months (Same duration of closure

for bicyclists and pedestrians on separate bicycle/pedestrian bridge)

$3.8 to $9.8 million $63.3 million

B Yes 24 months $3.8 to $9.8 million $63.3 million

B with Temporary Detour Bridge No Not closed Not applicable Not applicable

C Yes 42 months $6.7 to $17.0 million $110.8 million

D No Not closed Not applicable Not applicableE No Not closed Not applicable Not applicablea Owner and labor incomeb Travel time and operating costs

Table 4.2-1. Bridge Closure, Duration, Business Loss, and Commuter Cost.



Figure 4.2-2. Bridge Construction Cost in 2012 Millions of Dollars by Alternative and Bridge Type.

Figure 4.2-1. Total Construction Cost in 2012 Millions of Dollars by Alternative and Bridge Type.

4 - 8 Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement


Figure 4.2-4. East-side Connection Construction Cost in 2012 Millions of Dollars by Alternative.

Figure 4.2-3. West-side Interchange Construction Cost in 2012 Millions of Dollars by Alternative.



Table 4.2-2 summarizes the potential ability to phase construction of the Build alternatives.

4.2.4 Bicyclists and Pedestrians Bicyclist and pedestrian facilities and connections to other facilities would vary among the Build alternatives, as shown in Table 4.2-3.

time, a rehabilitated or new bridge could use the existing west-side interchange until there was adequate funding to reconstruct the interchange. Construction of Alternative E could not be phased in this way because it would not use the existing alignment. A new bridge and interchange would need to be built at the same time to connect the new bridge with OR 43 north of the existing interchange. Alternative E would require full funding to complete the new bridge and the west-side interchange.

Alternative A could be staged in three phases if necessary—construction of the bicycle and pedestrian bridge, rehabilitation of the vehicular bridge, and reconstruction of the interchange.

Construction of a new bridge under Alternative D would be phased. Half of the bridge would be constructed alongside the existing bridge. Traffi c would be switched to the new half-bridge, and the existing bridge would be demolished. The second half of the bridge would then be constructed and traffi c would be centered on the new structure.

Figure 4.2-5. Build Alternative Alignments.

Alternative Phase Construction?A Yes

B YesC YesD Yes

E No(on a new alignment)

Table 4.2-2. Can Construction Be Phased?



Element A B C D E

Is there a barrier or separation for bicyclists and pedestrians on the shared-use path from motorized traffi c?

Yes(Separate bridge)

Yes(Railing and

curb)

Yes(Separates

bicyclists and pedestrians on separate bridge deck)

Yes(for pedestrians

only; bicycle lane next to motorized

traffi c)

Yes(Curb only)

What is the total width designated for bicyclists and pedestrians?

20 feet 20 feet 20 feet 37 feet 24 feet

How many potential bicyclist and pedestrian confl ict points with vehicles exist in the west-side interchange?

03

(North, south, and west legs)

04

(Allfour legs)

4(All

four legs)

Might visually impaired pedestrians be adversely impacted?

No Yes No No No

Are bicyclists and pedestrians routed through the interchange?

No Yes No Yes Yes

Are there safety and security concerns due to complete separation from other bridge users?

Yes(Separate bridge)

NoYes

(Separate bridge deck)

No No

Is there a link to the Willamette Greenway Trail and the future streetcar line?

Yes(Both sidesof bridge)

Yes(Both sides of bridge)



Yes(Only from north side of bridge)

Is there a linkto the Springwater Corridor Trail?

Yes(Must use

surface streets)

Yes(Must use

surface streets)

Yes(Ramp

provided from bridge)

Yes(Must use

surface streets)

Yes(Must use

surface streets)

Table 4.2-3. Bicyclist and Pedestrian Elements by Build Alternative.



transit options, such as streetcars. However, the improvement in transit reliability would be minimal because of peak period traffi c congestion and because dedicated transit lanes would not exist on OR 43 or SE Tacoma Street. (Such dedicated lanes would only be on the bridge.)

Table 4.2-4 summarizes information about transit elements among the Build alternatives.

4.2.6 Residential Displacements Residential displacements would vary among the Build alternatives. All residential displacements would occur on the east side of the river affecting the following developments:

• Sellwood Harbor Condominiums (immediately south of the existing bridge)

• River Park Condominiums (immediately north of the existing bridge)

• Grand Place Condominiums (north of SE Tacoma Street between SE Grand Avenue and SE Oaks Park Way)

Each Build alternative would displace between one and six residential units, as shown in Table 4.2-5.

Figure 4.2-6 shows the residential displacements by Build alternative.

4.2.5 Transit Transit over the Sellwood Bridge would be reinstated under all Build alternatives. All Build alternatives would provide for 44 feet of railway right-of-way at the west end of the bridge to accommodate two streetcar rail tracks and space for a paved Willamette Greenway Trail (West Bank). Among Build alternatives, the west-side interchange and basic bridge cross-section would affect transit.

• Bus stops. Bus stops for Alternatives B, D, and E would be located in the west-side interchange area, allowing for effi cient connections between bicyclists, pedestrians, transit, and the planned future streetcar line. For Alternatives A and C, bus stops would be located north of the west-side interchange at SW Taylors Ferry Road.

• Ability to provide transit reliability and to accommodate future transit. Dedicated transit lanes on the bridge (Alternative E) would increase transit reliability compared to basic bridge cross-sections under the other Build alternatives. The dedicated transit lanes would provide for free fl ow of transit vehicles across the bridge (unimpeded by automobile and truck traffi c) and would better accommodate future

Element A B C D E

Are bus stops located within the west-side interchange area? No Yes No Yes Yes

Are there dedicated transit lanes? No No No No Yes

Table 4.2-4. Transit Elements by Build Alternative.

Alternative Number of Displaced Residential Units

A 1 unit in River Park

B 1 unit in River Park

B with Temporary Detour Bridge 1 unit in River Park

C 1 unit in River Park

D 5 (4 units in Sellwood Harbor, 1 unit in River Park)

E 6 (All units in Grand Place)

Table 4.2-5. Residential Displacements by Build Alternative.



Figure 4.2-6. Residences Displaced by Build Alternatives.

Alternative A

Alternative CAlternative B and Temporary Detour Bridge

Alternative D Alternative E



Alternative Number of Displaced Businesses

A 9 (Sellwood Building)

B 9 (Sellwood Building)

B with Temporary Detour Bridge 10 (Sellwood Building and Riverside Corral)

C 10 (Sellwood Building and Staff Jennings)

D 9 (Sellwood Building)

E

48 (Sellwood Building, River Park Center,

and two vacant offi ce spaces in Grand Place)

• Alternative B with temporary detour bridge. Buildings in the portion of Brinsfi eld Boat Basin north of SE Tacoma Street would be demolished and displaced. No buildings in the portion of Brinsfi eld Boat Basin south of SE Tacoma Street would be displaced.

• Alternative C. Some of the accessory buildings part of Brinsfi eld Boat Basin south of SE Tacoma Street would be displaced with the SE Grand Avenue Loop option (which is described in Subsection 4.3.4). Access from OR 43 to River View Cemetery would be removed. (This is discussed in Subsection 4.2.8.)

• Alternative E. The accessory buildings part of Staff Jennings would be displaced.

4.2.8 Maintenance of Access to Businesses and Residences

Access to all non-displaced businesses and residences in the project area would be maintained during and after construction under all Build alternatives. However, the design of the trumpet interchange in Alternative C would require removal of the existing access point to River View Cemetery from OR 43 immediately south of the existing OR 43/Sellwood Bridge interchange. It is expected that this change in access would negatively impact the existing funeral home business within the cemetery; instead of the using the existing access from OR 43, visitors would use a circuitous route to reach the funeral home business from the

existing River View Cemetery access point on SW Taylors Ferry Road. The cemetery owners have indicated they would move the business to a different location if the access from OR 43 were closed.

4.2.7 Business Displacements The number of business displacements would vary among the Build alternatives. Business displacements under the Build alternatives would affect the following businesses:

• Staff Jennings (a commercial boat dealership that is located on the west side immediately north of the existing bridge)

• Sellwood Building (a professional offi ce building with nine businesses that is located below the east approach of the existing bridge)

• River Park Center (a three-story professional offi ce building with approximately 37 separate businesses that is located east of the existing bridge on SE Spokane Street)

• Grand Place (with two vacant offi ce spaces that is located in a mixed-use building north of SE Tacoma Street between SE Grand Avenue and the Springwater Corridor Trail)

• Riverside Corral (an adult entertainment lounge that is located in the northwest quadrant of the SE Tacoma Street/SE 6th Avenue intersection)

Each Build alternative would displace between 9 and 48 businesses, as shown in Table 4.2-6.

Figure 4.2-7 shows the business displacements by Build alternative.

In addition to these business displacements, the following business impacts would occur:

Table 4.2-6. Business Displacements by Build Alternative.



Figure 4.2-7. Businesses Displaced by Build Alternatives.

Alternative A

Alternative B and Temporary Detour Bridge



Alternative C

Alternative D

Figure 4.2-7, cont. Businesses Displaced by Build Alternatives.



Impacts at fi ve other park and recreational facilities would be specifi c to individual Build alternatives, as described in Table 4.2-8.

4.2.10 Section 4(f) Section 4(f) of the U.S. Department of Transportation (USDOT) Act of 1966 applies to this project because eligible recreational resources and historic properties are present and would be impacted by the Build alternatives. The Draft Section 4(f) Evaluation is appended to this document. The summary below is included in this chapter because this federal law could strongly infl uence the identifi cation of a preferred alternative.

Section 4(f) requires that particular attention be given to the proposed use of any land from a signifi cant publicly owned park or recreation area; wildlife and waterfowl refuge; or historic site that is on or considered eligible for the National

Table 4.2-7 summarizes the status of the River View Cemetery access from OR 43 under each Build alternative.

4.2.9 Park and Recreational Facility Impacts

Impacts at the following three park and recreational facilities would be similar for all Build alternatives:

• Springwater Corridor Trail• Willamette Greenway Trail (East Bank)• Willamette Greenway Trail (West Bank)

Alternative E

Figure 4.2-7, cont. Businesses Displaced by Build Alternatives.

Alternative Access from OR 43?

A Yes

B Yes

C No

D Yes

E Yes

Table 4.2-7. Status of River View Cemetery Access from OR 43.



recreation area, wildlife and waterfowl refuge, or historic site resulting from the use.

A feasible alternative is one that could be built based on sound engineering principles. A determination of prudence requires weighing numerous factors, such as: social, economic, environmental justice, and environmental impacts; community disruption; extraordinary construction, maintenance, or operational costs; unique problems; or a combination of these factors.

Section 4(f) resources in the study area (Willamette Greenway Trail [East and West banks] and Springwater Corridor) could not be avoided under any feasible or prudent alternative because these resources are aligned north-south and extend

Register of Historic Places (NRHP or National Register). Project actions requiring the use of such resources must document that no feasible and prudent alternatives to their use exist, and must fully consider measures to minimize harm to those resources.

Section 4(f) specifi es that the Federal Highway Administration (FHWA) may only approve a transportation project requiring the use of a Section 4(f) resource if:

1. There is no prudent and feasible alternative to using that land; and

2. The program or project includes all possible planning to minimize harm to the park,

Park or Recreational

Facility A B B/TDB C D E

OaksPioneer Park 0.12 acre None

Visual and noise

impacts from temporary

detour bridge structure

None None

Visual and noise impacts

from bridge structure

Sellwood Riverfront Park

0.38 acre (Bike/ped

bridge crosses above park)

None None None None

None(but new bridge is

adjacent to park)

Sellwood Bridge Recreational Trail

Bike/ped facility over river closed

during construction


during construction

None(bike/ped

facility provided

across river)


during construction

None(bike/ped

facility provided

across river)

None(bike/ped

facility provided

across river)

PowersMarine Park 1.57 acres 2.15 acres 2.15 acres 1.46 acres 2.11 acres 0.76 acre

Willamette Moorage Park 2.22 acres 1.75 acres 2.15 acres 2.86 acres 1.75 acres 3.05 acres

Total Facilities Impacteda 8 6 6 6 5 7

a Total includes all park and recreational facilities impacted by the Build alternative.B/TDB = Alternative B with temporary detour bridge

Table 4.2-8. Alternative-Specifi c Adverse Impacts to Park and Recreational Facilities.


Key D i f fe rent ia to rs bet ween Bu i ld Al te rnat ive E lements Chapte r 4 : Compar i son o f A l te rnat ives

4.2.11 Regulated Floodway The 100-year base fl ood elevation is the fl ood level that has a one percent chance of being equaled or exceeded each year. The Build alternatives vary in how they would change the base fl ood elevation, as shown in Table 4.2-10. Within the 100-year base fl ood elevation is the regulated fl oodway. Impacts to the regulated fl oodway depend on the number of piers, the location of the piers in the river, and the size and design of the piers.

All Build alternatives other than Alternative D would contribute to a small increase in the base fl ood elevation and, therefore, would require amendment of the regulated fl oodway or a change in design to achieve no net rise. As currently designed, if Alternatives A, B, C, or E are selected, they would create a net rise in the base fl ood elevation. The boundaries of the regulated fl oodway or the conveyance capacity of the fl oodway would need to be altered to bring the net rise back to zero. Once a preferred alternative has been identifi ed, engineering design work would be undertaken to avoid this impact. If the bridge piers could not be redesigned to avoid this impact, the fl oodway would need to be altered to achieve no net rise.

4.3 Key Differentiators between Build Alternative Elements

The following subsections describe the key differentiators among the following elements of the Build alternatives:

• Alignment

• West-side interchange type

• Basic bridge cross-section

• SE 6th Avenue intersection—neighborhood cut-through traffi c versus traffi c operations

• Rehabilitation versus replacement

outside the study area. Because there is no feasible and prudent avoidance alternative, FHWA may approve only the alternative that causes the least overall harm based on an assessment of the following seven factors:

1) The ability of the alternative to mitigate adverse impacts to each Section 4(f) property (including any measures that result in benefi ts to the property)

2) The relative severity of the remaining harm, after mitigation, to the protected activities, attributes, or features that qualify each Section 4(f) property for protection

3) The relative signifi cance of each Section 4(f) property

4) The views of the offi cial(s) with jurisdiction over each Section 4(f) property

5) The degree to which each alternative meets the purpose and need for the project

6) After reasonable mitigation, the magnitude of any adverse impacts to resources not protected by Section 4(f)

7) Substantial differences in costs among the alternatives

The Final Section 4(f) Evaluation will address each of the above factors for the preferred alternative. The preferred alternative will need to be identifi ed in accordance with these factors.

As noted in Subsection 4.2.9, impacts at the following three park and recreational facilities would be similar for all Build alternatives:• Springwater Corridor Trail• Willamette Greenway Trail (East Bank)• Willamette Greenway Trail (West Bank)

Impacts at fi ve other park and recreational facilities would be specifi c to individual Build alternatives, as described in Table 4.2-9.



Park or Recreational

Facility A B B/TDB C D E

OaksPioneer Park 0.12 acre None

Visual and noise

impacts from temporary

detour bridge structure

None None

Visual and noise impacts

from bridge structure


0.38 acre (Bike/ped

bridge crosses above park)

None None None None

None(but new bridge is

adjacent to park)



during construction


during construction

None(bike/ped

facility provided

across river)


during construction

None(bike/ped

facility provided

across river)

None(bike/ped

facility provided

across river)

PowersMarine Park 1.57 acres 2.15 acres 2.15 acres 1.46 acres 2.11 acres 0.76 acre

Willamette Moorage Park 2.22 acres 1.75 acres 2.15 acres 2.86 acres 1.75 acres 3.05 acres

Total Facilities Impacteda 8 6 6 6 5 7

a Total includes all park and recreational facilities impacted by the Build alternative.B/TDB = Alternative B with temporary detour bridge

Table 4.2-9. Alternative-Specifi c Adverse Impacts to Section 4(f) Properties.

Alternative Bridge Type

100-Year Base Flood Elevation Change

A Rehabilitated bridge with cable-stayed bicycle/pedestrian bridge 0.06 foot

Rehabilitated bridge with stress-ribbon bicycle/pedestrian bridge 0.07 foot

B Rehabilitated bridge 0.03 foot

C Through-arch 0.02 foot

D Deck-arch No change

Delta-frame -0.02 foot

E Box-girder 0.02 foot

Through-arch 0.02 foot

Table 4.2-10. Change in Base Flood Elevation by Build Alternative and Bridge Type.

4 -2 0 Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement


would require full funding to complete the new bridge and the west-side interchange.

• Impact Staff Jennings commercial business more than Alternatives A, B, and D because more right-of-way would be required, structures would be displaced, and the bridge would be adjacent to the main building (see Figure 4.2-7).

4.3.2 West-side Interchange Type Three different grade-separated interchange confi gurations have been proposed for the west end of the Sellwood Bridge at OR 43—roundabout (Alternatives A and B), trumpet (Alternative C), and single-point signalized (Alternatives D and E) interchanges. Figure 4.3-1 shows these interchange confi gurations.

Traffi c It is expected that under all three interchange types, eastbound traffi c during the afternoon/evening peak period would continue to back up across the Sellwood Bridge. Such back ups, when reaching the west-side interchange, would differ based on the interchange type.

• Roundabout. A roundabout interchange could impede westbound traffi c fl ow within the roundabout during the afternoon/evening peak period because eastbound traffi c would back up along SE Tacoma Street and the Sellwood Bridge, which would shut down traffi c circulation within the roundabout. This would cause intersection gridlock that might not occur in the single-point signalized or trumpet interchange types. This gridlock could exacerbate traffi c queue lengths extending from each approach to the roundabout. To mitigate this occurrence, ramp metering would be installed on incoming ramps to the roundabout, somewhat undermining the free traffi c fl ow a roundabout is designed to promote.

• Trumpet. A trumpet interchange would not create traffi c gridlock in the interchange during the peak period. This is a free-fl ow design in a system with inherent bottlenecks.

4.3.1 Alignment The Build alternatives would have two potential alignments—the existing alignment (Alternatives A, B, C, and D) and an alignment to the north of the existing alignment (Alternative E), as shown on Figure 4.2-5 in Subsection 4.2.3.

Because Alternative E would be on a different alignment than the other four Build alternatives, it would have different impacts. Alternative E would:

• Displace 48 businesses (216 employees), although the viability of the displaced businesses is not dependent on a specifi c location; the businesses could likely fi nd replacement offi ce space without major diffi culty. The other Build alternatives would displace either 9 or 10 businesses (between 30 and 62 employees).

• Maintain a river crossing (via the existing Sellwood Bridge) during construction (similar to Alternative D and Alternative B with a temporary detour bridge). Alternatives A, B, and C would not maintain a river crossing during construction.

• Require the most right-of-way acquisition (11.6 acres). The other Build alternatives would require acquisition of between 10.5 and 10.8 acres of right-of-way.

• Adversely impact Oaks Pioneer Church by its alignment adjacent to the church. No other Build alternative would have permanent adverse effects on the church.

• Be inconsistent with the City of Portland’s Willamette Greenway Plan (1987) because it would cross a designated view corridor on SE Spokane Street. The other Build alternatives would be consistent with this plan because they would not cross SE Spokane Street.

• Not be able to be phased. A new bridge and interchange would need to be built at the same time to connect the new bridge with OR 43 north of the existing interchange. Alternative E



Alternative A (Roundabout) Alternative C (Trumpet)Alternative B (Roundabout)

Alternative D (Signalized) Alternative E (Signalized)

Figure 4.3-1. West-side Interchange Types.



would include unsignalized crossings on single-lane approaches. Visually impaired pedestrians would experience greater crossing diffi culties and safety risks at roundabouts compared with at intersections having typical traffi c controls. This would be considered an adverse impact to the visually impaired.

• Bus stops. Bus stops for Alternatives B, D, and E would be located in the west-side interchange area, allowing for effi cient connections between bicyclists, pedestrians, transit, and the planned future streetcar line. For Alternatives A and C, bus stops would be located north of the west-side interchange at SW Taylors Ferry Road.

Table 4.3-2 shows the differences between the Build alternatives’ west-side interchange types related to potential bicyclist and pedestrian confl ict points with vehicles and transit access.

Although Alternative D would have four confl ict points, the signalized intersection would allow bicyclists and pedestrians to safely maneuver through the intersection. Under Alternative B, free-fl ow movements in the roundabout would be interrupted by bicyclists and pedestrians in the roundabout area, which could negatively affect bicyclist and pedestrian safety.

• Single-point Signalized. A single-point signalized interchange would not create traffi c gridlock in the intersection during the peak period.

Each Build alternative’s intersections at OR 43 and the Sellwood Bridge would operate acceptably before and after the afternoon/evening peak period. Table 4.3-1 summarizes traffi c operations by interchange type at the Sellwood Bridge/OR 43 interchange.

Bicyclists and Pedestrians The west-side interchange would also affect bicyclist and pedestrian travel. Although Alternatives A and B would have a roundabout for the west-side interchange, bicyclist and pedestrian travel would differ because Alternative A would include a separate bicycle/pedestrian bridge.

• Routing. Alternatives D and E would provide the most direct routing through the west-side interchange for bicyclist and pedestrian movements. Alternative B routing through the roundabout would be less direct than that of Alternatives D and E. Alternatives A and C would remove bicyclists and pedestrians from the west-side interchange.

• Visually impaired pedestrians. The west-side interchange roundabout under Alternative B

Table 4.3-1. Traffi c Operations by Interchange Type at the Sellwood Bridge/OR 43 Interchange.

ElementRoundabout

(A)Roundabout

(B)Trumpet

(C)Signalized(D and E)

Would interchange be congested at morning peak period?

Moderately congested




Would interchange be congested at afternoon peak period?

Highly congested (with ramp metering)

Severely congested

(Bicyclists and pedestrians in roundabout)

Highly congested Highly congested

Could westbound traffi c impede eastbound traffi c during afternoon and evening peak periods?

Yes Yes No No



Alternatives A, B, and D would be consistent with both documents.

• Width of roadway for motorized vehicles. The cross-section of lane width plus shoulder affects the ability of the roadway to handle larger vehicles and provide passing area for emergency vehicles; affects the operations of the roadway when vehicles are disabled; and provides a margin of safety or recovery area when vehicles depart the lane because of driver error or accident. The minimum shoulder width required to keep a disabled car from obstructing the travel lane is 6 feet. The width of travel lanes and shoulder areas varies by alternative.

– Alternatives A, C, D, and E would have standard 12-foot travel lanes. Shoulders for these alternatives would vary from zero (Alternative E) to 6.5 feet, where the shoulder was also a bike lane (Alternative D).

– Alternative A would have 12-foot travel lanes with a 6-foot shoulder.

– Alternative B would have only 11-foot travel lanes, but these would be combined with 5-foot shoulders that would not be shared with bicyclists.

– Alternative C would have 12-foot travel lanes with a 3-foot shoulder.

4.3.3 Basic Bridge Cross-sectionTotal bridge width, curb-to-curb width (roadway), and number of travel through lanes characterize the benefi ts and drawbacks for each of the basic bridge cross-sections (cross-section at the middle of the bridge). The following elements summarize the differentiating benefi ts and impacts of the basic bridge cross-sections on criteria developed through the public input process to evaluate project concepts and alternatives:

• Consistency with regional and community plans. Metro’s South Willamette River Crossing Study (1999) recommended that the Sellwood Bridge be rehabilitated or replaced as a two-lane bridge. This recommendation was incorporated into Metro’s 2004 Regional Transportation Plan. Alternative C would be inconsistent with these documents because the basic bridge cross-section would have three vehicular through lanes. However, three through lanes would provide fl exibility for future transit (such as instituting streetcar service across the bridge) and fl exibility during maintenance and emergency response. Although Alternative E would have four through lanes, two would be dedicated for transit only. Therefore, Alternative E would be consistent with the study because its basic bridge cross-section would have two vehicular through lanes.

Table 4.3-2. Potential Bicyclist and Pedestrian Confl ict Points with Vehicles and Transit Access by West-side Interchange Type.

ElementRoundabout

(A)Roundabout

(B)Trumpet

(C)Signalized(D and E)

Removes bicyclists and pedestrians from the interchange? Yes No Yes No

How many potential bicyclist and pedestrian confl ict points with vehicles? 0

3 (North, south, and west legs)

0 4 (All four legs)

Might visually impaired pedestrians be adversely impacted? No Yes No No

Includes bus stops within the interchange area? No Yes No Yes



• Ability to accommodate emergency and disabled vehicles and maintenance activities. Basic bridge cross-sections with more than two through lanes (Alternatives C and E) would provide better opportunities for emergency vehicles to navigate safely through traffi c, a designated vehicle breakdown area, and increased fl exibility in staging traffi c fl ow during periods of required maintenance than would Alternatives A, B, and D.

• Ability to provide fl exibility for responding to future transportation needs. Wider basic bridge cross-sections (Alternatives C, D, and E) would maintain the bridge’s fl exibility to address future transportation needs because they would provide opportunities for future rechannelization or reconfi guration of the bridge deck.

• Ability to provide transit reliability and to accommodate future transit. Dedicated transit lanes on the bridge (Alternative E) would increase transit reliability compared to the basic bridge cross-sections under the other Build alternatives. The dedicated transit lanes would provide for free fl ow of transit vehicles across the bridge (unimpeded by automobile and truck traffi c). Four-lane basic bridge cross-sections would better accommodate future transit options, such as streetcars, than would two-lane and three-lane alternatives. However, the improvement in transit reliability would be minimal because of peak-period traffi c congestion and because the dedicated transit lanes would not exist on OR 43 or SE Tacoma Street. (Such dedicated lanes would only be on the bridge.)

Table 4.3-3 summarizes information about the basic bridge cross-section elements among the Build alternatives.

– Alternative D would have two 12-foot travel lanes and 6.5-foot bike lanes that could serve as shoulders, but in doing so, would create confl icts with bicyclists.

– Alternative E would have four 12-foot travel lanes and no shoulders. However, the outside lanes would be transit-only lanes, which could act as an escape area when not occupied by a transit vehicle.

Of the Build alternatives, Alternative A wouldoffer the standard lane width with the widest shoulder without creating confl icts with bicyclists because they would be on the separate bicycle/pedestrian bridge.

• Bicyclist and pedestrian connectivity, mobility, and safety. Alternatives A, B, C, and D would provide a barrier or separation for the shared bicycle/pedestrian path from motorized traffi c, but Alternative E would only provide a curb for separation from motorized traffi c. Alternative D is the only cross-section that would include designated bicycle lanes, which would separate recreational bicyclists (who would likely use the shared-use path) and commuting bicyclists (who would likely use the bicycle lanes). Alternative D also would have the most width designated for bicyclists and pedestrians (37 feet) compared to the other Build alternatives (Alternative E would have 24 feet; Alternatives A, B, and C would have 20 feet).

• Residential displacements. The basic bridge cross-section of Alternative E would be 75 feet wide. On its proposed alignment north of the existing bridge, it would displace more residences than Alternatives A, B, C, or D. Alternative D would have the widest basic bridge cross-section on the existing bridge alignment (64 feet wide). Consequently, it would displace more residences than Alternatives A (39 feet wide), B (57 feet wide), or C (45 feet wide).



Element A B C D E

Consistent with South Willamette River Crossing Study?

Yes Yes No Yes Yes

Number of vehicular travel through lanes

2 2 3 2 2 (and 2 transit-only lanes)

Number of residential units displaced

1 1 1 5 6

Total basic bridge cross-section width

39 feet 57 feet 45 feet 64 feet 75 feet

Curb-to-curb width 36 feet 32 feet 42 feet 37 feet 48 feet

Ability to accommodate emergency and disabled vehicles and maintenance activities?

High (2 lanes plus 6-foot

unobstructed shoulder)

Low (2 11-foot lanes, plus

5-foot shoulder)

Moderate (3 lanes, 3-foot

shoulders) Would depend on the ability of vehicles in the second lane to

move out of the way of opposing

emergency traffi c.

Moderate(2 lanes, plus 6.5-foot bike

lane)Space for

emergency passage and

disabled vehicles would come

at the expense of the bicycle lane. Creates

safety risks for bicyclists.

High (4 lanes, no shoulders)

Space exists to pull over

for emergency vehicles and

disabled vehicles. However,

doing so would confl ict with

transit vehicles.

Ability to providefl exibility for responding to future transportation needs?

Low(39 feet wide)

Medium(57 feet wide)

Medium(45 feet wide, three lanes)

Medium(64 feet wide)

High(75 feet wide,

four lanes)

Ability to increase transit reliability and accommodate future transit?

Low(No dedicated transit lanes)




Medium (Dedicated

transit lanes, but no transit

lanes on OR 43 or SE Tacoma

Street)

Table 4.3-3. Basic Bridge Cross-section Elements by Alternative.



• Install a signal. The intersection of SE Tacoma Street/SE 6th Avenue would include a signal. This option was evaluated under Alternatives D and E.

Figure 4.3-2 shows the three options at the SE Tacoma Street/SE 6th Avenue intersection.

Maintain Existing ConditionsMaintaining existing conditions would either not affect or minimally increase cut-through traffi c. It would continue to make north-south operations on SE 6th Avenue very diffi cult during peak hours. Essentially, only right turns could be made with ease. Any of the Build alternatives could maintain existing operations of intersections that cross SE Tacoma Street.

Create a SE Grand Avenue LoopThe extension of SE Grand Avenue would improve accessibility between the Sellwood Bridge and the areas north of SE Tacoma Street and west of SE 13th Avenue, but could moderately increase cut-through traffi c. North-south traffi c could also use the SE Grand Avenue undercrossing of the bridge to freely move between north of SE Tacoma Street and south of it without engaging SE Tacoma Street itself or a signal. This option could be incorporated in any of the Build alternatives except Alternative E.

Install a SignalInstalling a signal at the SE Tacoma Street/SE 6th Avenue intersection could substantially increase neighborhood cut-through traffi c without providing improved access to existing land uses. The signal would provide a “sheltered” left-turn onto SE 6th Avenue, providing motorists the option of using the signal to avoid congestion on SE Tacoma Street. Those using the signal to turn onto SE 6th Avenue would increase cut-through traffi c. The effect of the signal on operations on SE Tacoma Street, however would be to back up traffi c into the OR 43 interchange. Operations at the signal would be LOS F, meaning that it would take more than one phase of the signal for traffi c to make it through the intersection. This option was evaluated with

4.3.4 SE 6th Avenue Intersection—Neighborhood Cut-through Traffi c versus Traffi c Operations

Neighborhood cut-through traffi c and ease of operations of intersections that cross SE Tacoma Street are related. Improving the opportunity for vehicles to cross SE Tacoma Street at SE 6th Avenue would be a tradeoff because it would relieve the frustration of local traffi c trying to cross SE Tacoma Street, but at the same time would attract cut-through traffi c trying to avoid congestion on SE Tacoma Street.

Under all Build alternatives, SE Tacoma Street would be heavily congested during the afternoon/evening peak period. Only minimal gaps in the steady stream of westbound vehicles would allow eastbound motorists to make left turns onto side streets, such as SE 6th Avenue. Crossing SE Tacoma Street on SE 6th Avenue would be extremely diffi cult at unsignalized intersections during the peak period.

At the SE Tacoma Street/SE 6th Avenue intersection, three options have been evaluated. Although the options have been evaluated with specifi c alternatives, most are applicable to any of the Build alternatives. The exception is that the SE Grand Avenue Loop option would not work with Alternative E. The three options are:

• Maintain existing conditions. An eastbound left turn would be permitted at SE 6th Avenue. This option was evaluated under Alternatives A and B.

• Create a SE Grand Avenue Loop. Eastbound left-turn movements from SE Tacoma Street to SE 6th Avenue would be rerouted to a right-turn loop. A raised median would restrict left-turn movements to SE 6th Avenue. Vehicles would turn right at SE 6th Avenue, turn right at SE Tenino Street, pass under the bridge via SE Grand Avenue (lowered and extended to SE Tenino Street), and intersect with SE Spokane Street. This option was evaluated under Alternative C.



Alternatives D and E, but could be incorporated in any of the Build alternatives. Because of the negative performance of this option, Alternatives D and E were evaluated without this option in the Sellwood Bridge Project Transportation Technical Report (CH2M HILL et al., 2008) to determine operations levels for the west-side interchange.

Table 4.3-4 summarizes the potential for neighborhood cut-through traffi c increases by Build alternative.

Figure 4.3-2. East-side Connection.

Alternatives A and B Alternative C

Alternative D Alternative E


Sect ion 4( f ) P re l imina r y Leas t Ha rm Analys i s Chapte r 4 : Compar i son o f A l te rnat ives

and $356 million. Cost estimates for Alternatives C, D, and E range between $280 million and $361 million. Alternatives A and B would limit the bridge type to use of the existing continuous truss span. Alternatives D and E would have more fl exibility for the bridge type.

Table 4.3-5 summarizes the number of vehicular bridge design types and the cost ranges for the rehabilitation and the replacement alternatives.

4.4 Section 4(f) Preliminary Least Harm Analysis

According to 23 CFR 774.3(c), because there is no feasible and prudent avoidance alternative, FHWA may approve only the alternative that causes the least overall harm based on an assessment of the seven factors listed in 23 CFR 774.3(c)(1):

i) The ability of the alternative to mitigate adverse impacts to each Section 4(f) property (including any measures that result in benefi ts to the property)

ii) The relative severity of the remaining harm, after mitigation, to the protected activities,

4.3.5 Rehabilitation versus Replacement

Alternatives A and B would rehabilitate the existing bridge. Alternatives C, D, and E would replace the existing bridge. Although Alternatives A and B are called bridge rehabilitation options, most of the elements of the existing bridge would be replaced. The only elements of the bridge that would be retained are the steel truss and piers. New elements would include the deck, deck support, two additional trusses, and new approach spans. The existing piers would be widened to provide structural support for accommodating heaver vehicles and to support the wider deck required for auxiliary lanes that would provide better operations at the interchange.

As illustrated on Figure 4.2-1 (located in Subsection 4.2.2), the construction cost to rehabilitate the existing bridge would be higher than the construction cost to replace the bridge under Alternatives C, D, and E (box-girder bridge). In 2012 dollars, the construction cost estimates for Alternatives A and B range between $331 million

Element

No Signal at SE 6th Avenue and SE Tacoma Street

(A and B)SE Grand

Avenue Loop (C)

Signal at SE 6th Avenue and SE Tacoma Street

(D and E)Potential increasesin neighborhoodcut-through traffi c

None to minimal Minimal to moderate Moderate to substantial

Does the option affect operations at west-side interchange?

No No Yes

Table 4.3-4. Potential for Neighborhood Cut-through Traffi c Increases by Build Alternative.

ElementRehabilitation

Alternatives (A, B)Replacement

Alternatives (C, D, E)

Number of vehicular bridge design types

1(Existing truss)

At least 2(Bridge types could include through-arch,

delta-frame, deck arch, or box-girder)Construction cost range (2012 millions) $331–$356 $280–$361

Table 4.3-5. Vehicular Bridge Design Types and Cost Ranges (2012 Dollars) of Rehabilitation and Replacement Alternatives.



The Final Section 4(f) Evaluation will address each of the above factors for the preferred alternative, which will be selected in accordance with these factors.

Table 4.4-1 provides a preliminary least harm analysis for each Section 4(f) resource (at which a use would occur from one or more Build alternative). Table 4.4-2 provides a quantitative assessment for each Build alternative of the total number of Section 4(f) resources that would be used and the acres of land that would be incorporated.

attributes, or features that qualify each Section 4(f) property for protection

iii) The relative signifi cance of eachSection 4(f) property

iv) The views of the offi cial(s) with jurisdiction over each Section 4(f) property

v) The degree to which each alternative meets the purpose and need for the project

vi) After reasonable mitigation, the magnitude of any adverse impacts to resources not protected by Section 4(f)

vii) Substantial differences in costs among the alternatives

Section 4(f) Resource Alternative

Section 4(f) Use?

Relative Net Harm to Section 4(f) Resource after Measures to Minimize Harm

Springwater Corridor Trail

A Yes Equal to all Build alternativesB Yes Equal to all Build alternatives

B/TDB Yes Equal to all Build alternativesC Yes Equal to all Build alternativesD Yes Equal to all Build alternativesE Yes Equal to all Build alternatives

Willamette Greenway Trail (East Bank)




A Yes Greater than the other Build alternativesB No None

B/TDB No NoneC No NoneD No NoneE No Not a Section 4(f) use; overall impacts greater than

Alternatives B, B (with temporary detour bridge), C, and D, but less than A

Table 4.4-1. Preliminary Least Harm Analysis by Section 4(f) Resource.

4 -3 0 Se l lwood B r idge Pro ject D ra f t Env i ronmenta l Impact S ta tement



Section 4(f) Use?


Oaks Pioneer Park

A Yes Greater than the other Build alternativesB No Not a Section 4(f) use; overall impacts equal to

Alternatives C and D, but less than Alternatives A, B(with temporary detour bridge), and E

B/TDB Yes Less than Alternative A, but greater than Alternatives B, C, D, and E

C No Not a Section 4(f) use; overall impacts equal to Alternatives B and D, but less than Alternatives A, B(with temporary detour bridge), and E

D No Not a Section 4(f) use; overall impacts equal to Alternatives B and C, but less than Alternatives A, B(with temporary detour bridge), and E

E No Not a Section 4(f) use; overall impacts greater than Alternatives B, C, and D, but less than Alternatives A and B (with temporary detour bridge)


A Yes Equal to Alternatives B and C, but greater than B(with temporary detour bridge), D, and E

B Yes Equal to Alternatives A and C, but greater than B(with temporary detour bridge), D, and E

B/TDB No Not a Section 4(f) use; overall impacts equal to Alternative D, less than A and B, but greater than E

C Yes Equal to Alternatives A and B, but greater than B(with temporary detour bridge), D, and E

D No Not a Section 4(f) use; overall impacts equal to Alternative B (with temporary detour bridge), less than A and B, but greater than E

E No Not a Section 4(f) use; overall impacts less than all Build alternatives

Powers Marine Park

A Yes Equal to Alternatives B, B (with temporary detour bridge), and D; less than C, but greater than E

B Yes Equal to Alternatives A, B (with temporary detour bridge), and D; less than C, but greater than E

B/TDB Yes Equal to Alternatives A, B, and D; less than C, but greater than E

C Yes Greater than the other Build alternativesD Yes Equal to Alternatives A, B, and B (with temporary detour

bridge); less than C, but greater than EE Yes Less than the other Build alternatives

Willamette Greenway Trail (West Bank)



Table 4.4-1, cont. Preliminary Least Harm Analysis by Section 4(f) Resource.




Section 4(f) Use?


Willamette Moorage Park

A Yes Greater than Alternatives B, B (with temporary detour bridge),and D, but less than C and D

B Yes Equal to Alternatives B (with temporary detour bridge) and D, but less than A, C, and E

B/TDB Yes Equal to Alternatives B and D, but less than A, C, and EC Yes Equal to Alternative E, but greater than A, B, B

(with temporary detour bridge), and DD Yes Equal to Alternatives B and B (with temporary detour

bridge), but less than A, C, and EE Yes Equal to Alternative C, but greater than A, B, B (with

temporary detour bridge), and DRiver View Cemetery

A Yes Equal to Alternatives B, B (with temporary detour bridge), D, and E, but less than C

B Yes Equal to Alternatives A, B (with temporary detour bridge), D, and E, but less than C

B/TDB Yes Equal to Alternatives A, B, D, and E, but less than CC Yes Greater than the other Build alternativesD Yes Equal to Alternatives A, B, B (with temporary detour

bridge), and E, but less than CE Yes Equal to Alternatives A, B, B (with temporary detour

bridge), and D, but less than CSellwood Bridge (Historical Site)



B/TDB = Alternative B wtih temporary detour bridge

Table 4.4-1, cont. Preliminary Least Harm Analysis by Section 4(f) Resource.

AlternativeNumber of Section 4(f)

Resources Used Total Section 4(f) Land

Incorporated (acres)A 10 7.87B 8 7.48

B/TDB 8 7.48C 9 6.39D 7 7.46E 7 7.24

B/TDB = Alternative B wtih temporary detour bridge

Table 4.4-2. Summary of Impacts by Alternative.



The narrative analysis provided thus far in Sections 4.1 and 4.2, along with the comparative analysis provided in Tables 4.4-1 and 4.4-2, provide the substantive information needed to preliminarily address the 23 CFR 774.3(c)(3) “least harm analysis factors” provided in the modifi ed Section 4(f) statute published earlier this year. This discussion is provided in Table 4.4-3.

Table 4.4-3. Preliminary Least Harm Analysis by 23 CFR 774 Factors.a

Factor 1: “ The ability to mitigate adverse impacts to each Section 4(f) property (including any measures that result in benefi ts to the property)”; and

Factor 2: “ The relative severity of the remaining harm, after mitigation, to the protected activities, attributes, or features that qualify each Section 4(f) property for protection”

Discussion: There is no differentiation between Build alternatives in regard to Factors 1 and 2 for the following Section 4(f) resources:

• Springwater Corridor Trail. All Build alternatives would entail similar temporary closures of the trail that would be mitigated through the provision of similar detour accommodations during construction

• Willamette Greenway Trail (East Bank). All Build alternatives would entail similar temporary closures of the trail that would be mitigated through the provision of similar detour accommodations during construction

• Willamette Greenway Trail (West Bank). All Build alternatives would entail incorporating a similar amount of the existing trail and mitigating this impact through the same provision of an improved trail segment through the project study area

• Sellwood Bridge (Historical). All Build alternatives would result in a Section 4(f) use at the existing site that could not be feasibly mitigated for to avoid such a Section 4(f) use of this historic structure

At Sellwood Riverfront Park, Alternatives B, B (with temporary detour bridge), C, and D would have no Section 4(f) use or other impacts. Therefore, these four alternatives would have an equal least harm impact to the park in respect to Factors 1 and 2.

At Oaks Pioneer Park, Alternatives B, C, and D would have no Section 4(f) use or other impacts. Therefore, these three alternatives would have an equal least harm impact to the park in respect to Factors 1 and 2. (Alternatives B [with temporary detour bridge] and E would not have a Section 4[f] use, but would result in proximity impacts due to the associated structures of each.)

At Sellwood Bridge Recreation Trail, Alternative E would cause the least overall harm because it would allow bicyclists and pedestrians to continue to use the existing trail across the river while the new bridge was being constructed. Therefore, it would not subject users of the trail to using detours or traversing through a construction zone. Alternatives B (with temporary detour bridge) and D, although they both would provide river-crossing accommodations for bicyclists and pedestrians, would subject users to using detours and traversing through construction zones (with potential associated temporary trail closures, etc.).



At Powers Marine Park, Alternative E would have the least overall harm in respect to Factors 1 and 2 because it would convert signifi cantly less natural area land to transportation use (see Table 4.1-1), thereby allowing the most remaining natural area land to be used for mitigation and enhancement activities.

At Willamette Moorage Park, Alternatives B, B (with temporary detour bridge), and D would equally cause the least harm in respect to Factors 1 and 2 because they each would convert a similar amount of natural area land that would be signifi cantly less than with the other Build alternatives (see Table 4.1-2). This would thereby allow the most remaining natural area land to be used for mitigation and enhancement activities.

At River View Cemetery, all Build alternatives (aside from Alternative C) would equally cause the least harm in respect to Factors 1 and 2 because they would have very similar impacts to the property, both in terms of property functions impacted and total area of property incorporated into the project.

Conclusion: The preceding discussion suggests that Alternatives D and E would be roughly equal in regard to a consideration of “least harm” as it relates to Factors 1 and 2:

• Both alternatives would be equal in the total amount of uses of Section 4(f) resources(see Table 4.4-2).

• Both alternatives would allow for mitigation potential at similar levels to other alternatives (where a use of a Section 4(f) resource would be taking place)

• Alternative E would convert 1.30 more acres of natural area to transportation use at Willamette Moorage Park than Alternative D would; Alternative D would convert 1.35 more acres of natural area to transportation use at Powers Marine Park than Alternative E would

• At the six Section 4(f) resources where a least harm differentiation comparison can be made, Alternative D is tied for having the least overall harm at four of those resources, while Alternative E is tied for having the least overall harm at one of them, but is by itself as the alternative causing the least overall harm at two of them

• Overall, Alternative E would use 0.22 acre less of land from Section 4(f) resources thanAlternative D would

Factor 3: “The relative signifi cance of each Section 4(f) property”; andFactor 4: “The views of the offi cial(s) with jurisdiction over each Section 4(f) property”

Discussion:Of the fi ve publicb Section 4(f) resources where a least harm differentiation comparison can be made, the following categorization can be made in regard to the “signifi cance” of those resources based on the views of agency offi cials with jurisdiction over the respective Section 4(f) resources. This categorization is based on discussions with jurisdictional agency offi cials while conducting coordination activities over the course of the Sellwood Bridge project, not on explicit responses agency offi cials made related to Factors 3 and 4:

• Sellwood Riverfront Park. This park receives a very high number of visitors and is the site of various community and non-profi t events

Table 4.4-3, cont. Preliminary Least Harm Analysis by 23 CFR 774 Factors.a



• Sellwood Bridge Recreation Trail. The bridge trail is an integral link in the City of Portland’s well-used bicycle recreational trail system

• Oaks Pioneer Park, Willamette Moorage Park, and Powers Marine Park. Based on various discussions with different jurisdictional offi cials, there is not enough information to label any of these three parks as more “signifi cant” than the other parks

Conclusion: The preceding discussion suggests that Alternative D would have the “least harm” as it relates to Factors 3 and 4. Alternative D would have no Section 4(f) use at the following aforementioned signifi cant Section 4(f) resource sites—Sellwood Riverfront Park, Sellwood Bridge Recreation Trail, and Oaks Pioneer Park. Alternative D would have no impact of any kind at Sellwood Riverfront Park or Oaks Pioneer Park and would provide bicycle/pedestrian bridge-crossing accommodations during construction. Only Alternative B (with temporary detour bridge) would be somewhat similar in this regard, but the temporary detour bridge structure would have substantial non-Section 4(f) use proximity impacts at Oaks Pioneer Park.

Factor 5: “The degree to which each alternative meets the purpose and need for the project”

Discussion:The purpose of the Sellwood Bridge Project is to: “rehabilitate or replace the Sellwood Bridge within its existing east-west corridor to provide a structurally safe bridge and connections that accommodate multi-modal mobility needs.” The four major issues that defi ne the needs of the project are:

• Inadequate structural integrity to safely accommodate various vehicle types (including transit vehicles, trucks, and emergency vehicles) and to withstand moderate seismic events

• Substandard and unsafe roadway design

• Substandard pedestrian and bicycle facilities across the river

• Existing and future travel demands between origins and destinations served by the Sellwood Bridge exceed available capacity

All of the Build alternatives would provide a structurally safe bridge to replace the existing bridge and would meet the above four major needs. The “degree” to which the respective Build alternatives would do this is a consideration that must include a comprehensive determination of all subject areas assessed in this DEIS, which is being prepared in tandem with the Draft Section 4(f) Evaluation. Therefore, the response to Factor 5 relies upon the aforementioned consideration/determination process, which has not yet taken place, given that a preferred alternative is not being proffered by the DEIS. (A preferred alternative will be specifi ed in the project’s Final Environmental Impact Statement.)

Conclusion: Decision-makers will need to incorporate their determination on which Build alternative best meets the purpose and need for the DEIS as a whole (after considering all DEIS discipline reports) and apply it to Factor 5 in concert with the analysis of Build alternatives provided in the Draft Section 4(f) Evaluation.




avoiding each Section 4(f) resource, will specifi cally discuss measures proposed to minimize harm to each Section 4(f) resource, and, as noted, will discuss the rationale used to decide that the preferred alternative is the alternative that would result in the least overall harm according to the seven factors listed in 23 CFR 774.3(c)(1).

Factor 6: “ After reasonable mitigation, the magnitude of any adverse impacts to resources not protectedby Section 4(f)”

Discussion:A response to address the “magnitude of any adverse impacts to resources not protected by Section 4(f)” requires a totality of impacts consideration that takes into account the entire spectrum of natural and human resources addressed in the DEIS. This consideration is the task of decision-makers examining the various technical reports contained in the DEIS. As noted in the discussion under Factor 5, this consideration/determination process has not yet taken place, given that the preferred alternative is not being proffered in the DEIS.

Conclusion: Decision-makers will need to incorporate the overall DEIS determination regarding the respective post-mitigation impacts of all Build alternatives and apply it to a consideration of this least harm factor. In this way, impacts to non-Section 4(f) resources will play a substantial part (alongside impacts to resources protected by Section 4[f] that have been discussed in the Draft Section 4(f) Evaluation) in identifying the Build alternative that has the “least overall harm” in light of the Section 4(f) statute.

Factor 7: “ Substantial differences in costs among the alternatives”

Discussion:Respective Build alternative construction cost estimates (including right-of-way acquisition costs) are as follows:c

• Alternative A: $331–$337 million • Alternative B: $326 –$356 million • Alternative C: $280 million • Alternative D: $293 –$311 million • Alternative E: $281–$361 million

Conclusion: Alternative C clearly would be the least costly Build alternative. Whether the difference in cost between Alternative C and another Build alternative could be considered “substantial” in terms of percentages depends on the bridge type chosen within the alternative.

Notes:a The seven factors listed in this table correspond with 23 CFR 774.3(c)(1)(i) through (vii).b River View Cemetery is not publicly owned and, therefore, is not included in the discussion of Factors 3 and 4.c Cost ranges are provided where construction costs would differ according to the bridge type selected.


The Final Section 4(f) Evaluation, which will be prepared in conjunction with the Final Sellwood Bridge Project Environmental Impact Statement, will include a more detailed evaluation of the Section 4(f) resources associated with the preferred alternative. The detailed evaluation will explain more specifi cally the problems associated with

chapter 4. comparison of alternatives - sellwood bridge · additional investment would ... and the...

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