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HomeMy WebLinkAboutProject Narrative_NV request_3_18_16 (2)Project Narrative I-405, NE 30th Street Ramp Improvements March 17, 2016 Purpose WSDOT is requesting a variance from the requirements of City of Renton Municipal code to allow nighttime construction work.   Project Description To relieve congestion on local streets, WSDOT proposes to improve one I-405 interchange ramp within the City of Renton. The work at the I-405/Northeast (NE) 30th Street interchange includes widening and restriping the existing ramp to accommodate a second metered lane, constructing a retaining wall, and relocating the existing ramp meter. The City of Renton and WSDOT have been working collaboratively to resolve recurring congestion and queuing resulting from the operation of the ramp meters at the I-405 interchanges on NE 30th Street. This project will provide additional vehicle storage at the ramp meters and provide for more efficient ramp metering. The City is planning a complimentary project on NE 30th Street to add storage for overflow vehicles from the on-ramp by eliminating parking on NE 30th Street during peak periods. The combination of projects will enhance ramp operations and reduce congestion on local streets. The project is scheduled to be advertised to prospective bidders early May and construction is planned between July and September. However, to accommodate the unanticipated project delays, we are requesting that the Noise Variance permit be valid for the full two years allowed by Renton Municipal Code. Project Narrative I-405, NE 30th Street Ramp Improvements Project name, size and location of site Project Name: I-405, NE 30th Street Ramp Improvements. Project Size: The project area includes improving a) approximately 1,900 linear feet of the NE 30th Street to northbound I-405 on-ramp Project Location: The project is located on the NE 30th Street to northbound I-405 on-ramp, between I-405 Milepost (MP) 6.5 and MP 6.9, King County, City of Renton, Township 24 North, Range 5 East, W. M. Land use permits required for proposed project. Land use permits are not required for this project. A Nighttime Noise Variance is needed. Zoning designation of the site and adjacent properties. I-405 roadway and associated off/on ramps are within State roadway right of way and do not have a City zoning designation. Beyond the State roadway right of way the land use is designated R8-Residential 8 du/ac. Current use of the site and any existing improvements The current land use is a state transportation corridor including intersections with off and on-ramps. Existing improvements are associated with the roadway. They include on and off-ramps, electrical cabinetry and wiring, ditches, culverts, catch basins, storm water treatment facilities, pavement markings, traffic signals, signs and ramp meters. Special site features (i.e. wetlands, water bodies, steep slopes) May Creek flows beneath I-405, approximately 1,000 feet north of the NE 30th St. interchange. Impacts to May Creek are not anticipated. The project does not contain steep slopes and it is not located within a landslide hazard area. Soil type and drainage conditions The major soil type identified along the project is glacial till and advance glacial outwash deposits. However due to intense urbanization and previous I-405 construction, there is little natural soil within the project area. Surface water runoff from the existing roadway drains through a combination of open ditches and enclosed pipes. Minor roadway widening will occur on the NE 30th on-ramp.  An enclosed drainage will be provided and connected into WSDOT’s existing enclosed drainage system at the on-ramp, within WSDOT right of way. NPDES exempt This project is exempt from a Construction Stormwater General Permit (NPDES) because substantially less than one acre of land disturbance will occur and the site topography prevents any storm water from entering a waterway. Best Management Practices will further ensure compliance with State water quality standards. New impervious surface A total of 850 square feet of new impervious surface will be added to provide the additional vehicle storage. Small quantities of erosion control grasses and roadway shoulder gravels will be removed for the widening. Proposed use of the property and scope of the proposed development No change of land use will occur. The property will remain a transportation corridor. For plats indicate the proposed number, net density and range of sizes (net lot area) of the new lots Not applicable. This property is and will remain a transportation corridor. Access Site access will not change. Proposed off-site improvements (i.e. installation of sidewalks, fire hydrants, sewer main, etc.) None. Total estimated construction cost and estimated fair market value of the-proposed project. Construction cost and the fair market value is approximately $750,000. Estimated quantities and type of materials involved if any fill or excavation is proposed. Approximately 280 cubic yards of backfill soil will be needed to construct a retaining wall at NE. 30th. Number, type and size of any trees to be removed. None. Explanation of any land to be dedicated to the City None. Any proposed job shacks, sales trailers, and/or model homes None. Any proposed modifications being requested (include written justification) None. For projects located within 100 feet of a stream or wetland, please include distance in feet from wetland or stream to nearest area of work Project work will not occur within 100 feet of a steam or wetland. For projects located within 200-feet of Black River, Cedar River, Springbrook Creek, May Creek and Lake Washington please include the following additional information: Distance from closest area of work to the ordinary high water mark. Description of the nature of the existing shoreline The approximate location of and number of residential units, existing and potential, that will have an obstructed view in the event the proposed project exceeds a height of 35-feet above the average grade level Project work will not occur within 200’ of the listed waterbodies. Variance Request Justification: The burden of proof as to the appropriateness of the application lies with the applicant. In order to approve a variance request, the Reviewing Official must find all the following conditions exist: The applicant suffers practical difficulties and unnecessary hardship and the variance is necessary because of special circumstances applicable to subject property, including size, shape, topography, and location or surroundings of the subject property, and the strict application of the Zoning Code is found to deprive subject property owner of rights and privileges enjoyed by other property owners in the vicinity and under identical zone classification; WSDOT’s traffic analysis has determined that performing ramp closures during the day would result in traffic congestion due to high traffic volumes, loss of roadway capacity, and diminished access to local events. WSDOT recommends that lane closures and certain construction activities occur at night and continuous operation of construction activities such as pavement grinding can be ensured to avoid endangering personnel. To avoid disruptions to workers, pedestrians and motorists, and to maintain emergency and essential services, many construction activities must occur between the hours of 7:00 pm and 7:00 am, Monday through Sunday. Activities such as pavement repair, grinding, removal and replacement of pavement and pavement markings cannot be accomplished while traffic is present. Full or partial freeway, street and ramp closures are necessary for these activities. In addition, nighttime work is necessary to complete the project prior to the 2016-17 school year at Kennydale Elementary School, located just east of the N 30th Street project site. A primary benefit of the completed NE 30th ramp improvements is improving access to the school by reducing traffic congestion on NE 30th Street. Construction Considerations and Closures: Portions of the construction operations will occur during nighttime hours. The closures required for these operations are only feasible at night. This project will require roadway closures for construction personnel and equipment and personnel operating on the roadway. Estimate of required night work Based upon previous project schedules, WSDOT estimates that it will require 23 nights to complete the work. This estimate, shown below, includes the minimum amount of time necessary to safely complete the work: Striping mainline (gore area)(remove and install)         2 night Striping ramp (remove and install)                              2 night Setting and removing temporary concrete barrier             2 nights Paving and drainage                                                    4 nights Saw-cutting ITS loops on ramp         2 nights Drilling Soldier Pile Walls 6 nights                          Total estimated nights                                                        18 nights Contingency nights for weather and other factors               5 nights Total Estimated night work                                                   23 nights         The granting of the variance will not be materially detrimental to the public welfare or injurious to the property or improvements in the vicinity and zone in which subject property is situated; Granting of the variance will enhance public safety and reduce risks to property because nighttime traffic volumes are lighter, thus reducing the safety risks. Performing this work during nighttime hours and, if required, during weekend closures when the least amount of traffic is present will minimize risks to the traveling public and construction workers. In addition to the safety benefits of nighttime work, WSDOT, its contractors and subcontractors will follow all of the conditions, restrictions and mitigation measures pursuant to the City of Renton Municipal Code. The approval shall not constitute a grant of special privilege inconsistent with the limitation upon uses of other properties in the vicinity and zone in which the subject property is situated; and WSDOT agrees that the approval is the minimum variance that will accomplish the desired purpose. Approval of this request does not grant a special privilege inconsistent with roadway construction projects elsewhere. Nighttime roadway construction is a common and accepted practice to reduce congestion and inconvenience to motorists, expedite road building tasks, and enhancing work zone safety by conducting construction when partial or complete roadway and ramp closures are possible due to reduced traffic volumes. Utilities Plan, Generalized (sewer, water storm water, transportation improvements) Public utilities are not located within WSDOT right of way, however minor amounts of electrical conduit will be installed for the ITS system and illumination. See attached 60% plans p. 27-35 and p. 25-26 for details.