Draft terrestrial resources biological assessment
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- 2.2.1 JTA Phase Design
- 2.2.2. Future Phases
- 2.2.2.1. Split Diamond Alternative Construction Phasing
- 2.2.2.2 Northern Project Alignment (Agate Road to West Dutton Road)
- 2.2.3. Staging Areas and Access
2.2 Construction PhasingThe 2009 Oregon JTA (House Bill 2001), included funding for construction of a portion of Unit II of the Project. Because the completed North Medford Interchange improvements, completed in 2008, were considered Unit II of the Project, the JTA funding was designated for “Unit II,” is available for construction of the Bypass currently under consideration. In order to avoid confusion, the first phase of the Bypass construction – designated as Phase Unit II in the JTA funding bill – will be referred to as the “JTA phase” in this assessment. Regardless of which Build Alternative is selected after completion of the DEIS, the JTA phase will be built using State funding. If the No Build Alternative were selected as the Preferred Alternative, only the JTA phase would be built. If either of the Build Alternatives were selected, the JTA phase would be built first; the rest of the Preferred Alternative design would then be constructed in subsequent phases as funding is secured. A project phasing plan will be included in the Final Environmental Impact Statement (FEIS), as details about the timing, design, and extent of future phases have not been determined yet. 2.2.1 JTA Phase DesignThe JTA phase design is being advanced under conceptual design and is still under development. The goal of the JTA phase is to build a Bypass as far north as funding will allow. Design refinements are ongoing; as more detailed design information is available, more accurate cost estimates will be developed and engineers will be better able to assess the extent of the JTA phase design. The current cost estimates suggest that the JTA phase could extend from OR 62 near Delta Waters Road in Medford as far north as Corey Road near White City. However, as more detailed cost estimates become available and as ongoing agency and jurisdictional coordination proceeds, the design and extent of the JTA phase may change. In order to ensure that all potential impacts are evaluated and disclosed, this assessment assumes that the JTA phase would extend to Corey Road, its maximum possible extent. Figure 2-2 depicts the complete JTA phase with all attendant surface street improvements. The JTA phase would consist of a new limited-access Bypass using the alignments proposed in the Build Alternatives. There are three possible alignments of the JTA phase, based on the proposed alignments of Design Options A, B and C. However, there is only one design for the southern terminus of the JTA phase: a directional interchange with OR 62 in the vicinity of Delta Waters Road. If either of the two Build Alternatives were selected as the Preferred Alternative, in subsequent phases, the southern terminus would be modified to include all of the features of either the SD Alternative or the DI Alternative in this area. The design for the JTA phase’s south terminus does not preclude the selection of either of the two Build Alternatives. North of the proposed south terminus interchange, the Bypass would use the Medco Haul Road following the same alignment as both Build Alternatives, passing Commerce Drive and Coker Butte Road at grade. The proposed new roads that would provide a new approach to the INS facility as described for both Build Alternatives would be built. The JTA phase would cross over Vilas Road on an elevated structure, but would not include an interchange at Vilas Road. There would be no connection between the JTA phase and Vilas Road. The JTA phase would not include any of the changes to local roads in the vicinity of Vilas Road that are associated with the two Build Alternatives, nor would it include widening Vilas Road. There would be no changes to existing driveways in the vicinity of Vilas Road. As with the Build Alternatives, north of Justice Road there are three possible alignments: Design Options A, B, and C. The JTA phase alignment would be the same as the alignment of the Preferred Alternative, once selected. The three designs for the JTA phase would include an intersection with the existing OR 62 where Agate Road and OR 62 now intersect. The intersection design is still being developed, but it is likely to be a signalized intersection that provides for some free-flowing movements, as opposed to an interchange, which would allow complete free flowing transitions between the Bypass and OR 62. The main distinction between the JTA phase and non-JTA phase Design Options is the approach roadway into the intersection with OR 62. The JTA phase options tend to approach perpendicular to OR 62 to facilitate safety at the intersection. Consequently, all three Design Options extend a bit further north before curving east to meet OR 62. The non-JTA Design Options approach OR 62 at a more acute angle, as a result of the proposed interchange. Preliminary stormwater treatment design has only been completed for a portion of the JTA phase of the Project footprint. It extends from approximately Bullock Road in the south to approximately 1,000-feet south of the Vilas Road intersection. Three bioretention facilities have been sited and sized to meet ODOT stormwater treatment criteria within the three drainage basins this design covers. Treatment would include capture and treat systems that would divert runoff from new impervious surfaces and discharge via point source outfalls to local waterways. A more thorough discussion of engineering of these facilities is available for review in the Water Resources Technical Report: Highway 62 Corridor Solutions Project (URS 2010b). 2.2.2. Future PhasesIf the No Build Alternative is advanced from the DEIS as the Preferred Alternative, only the JTA phase of the Project would be built. The JTA phase design would be refined but there would be no additional phasing plan, as the JTA phase would constitute the entirety of the Project. If a Build Alternative is advanced as the Preferred Alternative, a detailed phasing plan will be developed and included in the project FEIS. This phasing plan will include more definitive designs for the JTA phase and will also identify subsequent project phases during which the remainder of the proposed Project would be constructed. 2.2.2.1. Split Diamond Alternative Construction PhasingThis assessment evaluates all Build Alternatives under consideration. The following information is based on conceptual-level design and very preliminary construction phasing. Construction methods have been conservatively estimated in approach and extent to allow for some modification in construction techniques while remaining within the terms of a PBO based on this assessment. As discussed previously, the SD Alternative involves a new interchange for the Bypass at I-5. The limits of construction would be surveyed and flagged and “no work” areas within the limits of construction would be identified and demarked with flagging or fencing. Additionally, a regulated work area would be established consistent with the delineated Ordinary High Water Elevation (OHWE). Activities within the regulated work area are restricted to specific construction tasks and may require approval from the project manager prior to execution of such tasks. Construction of soil erosion and sediment controls would be established in compliance with an approved Erosion and Sediment Control Plan (ESCP). Clearing of vegetation within the limits of construction would occur, as needed, to accommodate the access areas for equipment and personnel. Clearing would utilize equipment such as dozers, excavators, dump trucks, and possibly cranes or other specialized equipment. 2.2.2.2 Northern Project Alignment (Agate Road to West Dutton Road)Should either of the Build Alternatives be forwarded from the DEIS, the northern portion of the Project -- from the Bypass interchange with OR 62 near Agate Road to its northern terminus at West Dutton Road and OR 62) – would be built as the final construction phase, dependent upon a funding source. 2.2.3. Staging Areas and AccessConstruction staging areas and construction access have yet to be identified for proposed activities. It is assumed that much of the staging for construction will be sited on existing roadway sections or adjacent areas within the currently defined project footprint. It is also assumed that any staging areas will comply with the project’s ESCP and weed/invasive species control BMPs. For the purposes of this assessment, all habitats, populations, and specimens within the project footprint will be considered impacted by project activities, whether they are temporary (construction related) (or permanent (project element) impacts. Directory: HWY62 -> Terrestrial BA Terrestrial BA -> Draft Terrestrial Resources Biological Assessment oregon highway 62 corridor solutions project Download 486.24 Kb. Share with your friends:
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