Loading...
HomeMy WebLinkAboutEngineering Lavender Crossing Staff Report V4 3-31-23 Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 1 of 8 Memorandum To: Alex Jones, Planner Technician From: TJ Frans, Project Manager Steven Pendleton, Civil Plans Examiner II Re: Case Number ANN23-000007, SUP23-000004 Lavender Crossing Subdivision Date: January 30, 2023 The Engineering Department provides the following comments on a request by Riley Planning Services LLC, on behalf of Justin Fishburn, Gennie Fishburn, and Yellowstone Capital LLC, to annex parcel R3247801000 (approx. 8.18 acres) and R3248700000 (approx. 5.84 acres) with a proposed R-3 (High Density Residential) zoning designation, where designate HDR (High Density Residential) in the 2040 Comprehensive Plan, to include approval of a development agreement associated with ANN23-000007. Concurrently, the applicant is requesting approval for a special use permit for Lavender Crossing, a multi-family residential community with 288 multi-family residences spread throughout twelve (12) separate buildings. Each building consists of six (6) 1-bedroom units, six (6) 3-bedroom units and twelve (12) 2-bedroom units. The subject parcels are uniquely shaped infill parcels located at 4121 and 4114 Laster Lane in the unincorporated county of Canyon, which is generally located east Lake Road, and north and west of the Notus Canal. * Due to the nature, complexity and many civil improvements required of multi-family land development projects the Engineering Department recommends that this project be required to complete the land development process in the same manner as a standard subdivision and that said recommendation be made a condition of approval of this application. Development Plans 1. Development Plans – Prior to commencing construction and applying for building permits, plans must be prepared by the developer’s engineer and approved by the City Engineering Department which shall include the following items: a. Street section and alignment (including curb and gutter); b. Sidewalk (sidewalk width based on street classification); c. Sanitary sewer (per City and DEQ requirements); d. Potable water (per City and DEQ requirements); e. Stormwater facilities (per City requirements/storm water manual); Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 2 of 8 f. Street lighting (per City standards); g. Street signage (per City and MUTCD requirements); h. Vertical Datum based on NAVD 88 Datum. General 1. Applicant shall follow the requirements and processes of the subdivision ordinance for the development of this project. For the purposes of this project, all conditions outlined in the subdivision ordinance pertaining to receiving the City Engineers signature on, or the recordation of, a final plat shall be applied to the submission of building permits. 2. Easements for public utilities shall be as listed below. Easements will be required to be larger if deemed necessary by the City Engineer in order to facilitate future maintenance operations of utilities. a. 10 feet wide minimum. b. Domestic water only,15 feet wide minimum c. Sanitary sewer only, 20 feet wide minimum d. Sewer and water combined, 30 feet wide minimum i. Note: future permanent structures will not be permitted to be constructed within any easement granted to the City of Caldwell. Applicant shall ensure that civil design and easements provided to the City accommodate current and future construction needs of permanent structures such as covered parking structures, future buildings, etc. 3. Appropriate easements for emergency access, transmission lines and/or other utilities shall be clearly indicated, with recorded instrument numbers provided for said easements, on the construction drawings. 4. All utilities on and within the boundaries of the subdivision shall be located and/or relocated underground. 5. All street, sewer, water, fire protection, and street light facilities must be dedicated to the City. Some conveyance facilities for stormwater drainage may be eligible for dedication to the City. 6. Construction of facilities to be dedicated and/or within public right-of-way shall be performed by an appropriately licensed public works contractor and shall be inspected by and constructed to City of Caldwell specifications. 7. Prior to commencement of construction in any dedicated right-of-way, or construction of any improvement intended for dedication to the City or connected to a City facility, the City Engineering staff is to be notified. This preferably will take place in a pre-construction conference scheduled by the engineer of record in which all appropriate personnel and utilities are present. Appropriate City personnel are to be notified in advance of all testing (including compaction, pressure and coliform, etc.) and given opportunity to be present during conduct of the testing. The engineer of record or his designated representative is to witness all tests (not covered by City inspectors) and a log of inspection visits and testing results is to be kept by the engineer of record or his representative. Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 3 of 8 8. The developer is to employ a responsible design professional, preferably the engineer of record, to oversee and inspect construction, to perform and/or observe all requisite testing of completed facilities, and to certify that improvements have been constructed according to approved plans and in compliance with applicable City, State, and Federal standards. 9. The engineer of record shall be held responsible to ensure that subdivision improvements are in compliance with said engineer’s design. Following the construction of the subdivision improvements, the developers engineer shall provide the City of Caldwell Engineering Department with electronic (.dwg) format record drawings spatially referenced to the Idaho State Plane Coordinate System-West Zone, North America Datum (NAD) 83. Vertical control shall be referenced to the North America Datum (NAVD) 88 for future reference and to establish that the engineer of record has caused construction to occur in substantial compliance with the design of said engineer of record. 10. Any note, item or drawing element on the plats, construction drawings, engineering drawings and/or design drawings related to the property inconsistent with City Codes, Policies and/or Ordinances shall not be construed as approved unless specifically addressed and granted by City Council. Rights-of-Way 1. Laster Lane is classified as a Collector. The applicant shall dedicate as public right-of-way a minimum seventy (70’) feet right-of-way, extending the Laster Ln. alignment (per City Standard R-810C) from the existing right-of-way to the west to the sites proposed north access point. This may necessitate coordination with the Buxton Development (parcel 3247900000) to the north for access and dedication. 2. Applicant shall dedicate fifty-three (53) foot right of way to the north of the development for a primary point of access to Laster Ln. which will necessitate the requirement by the City of Caldwell Engineering Department to update the TIS for the proposed development to determine any necessary traffic mitigation requirements. If the access road is private, required width may be reduced with written consent by the engineering department. Access to Laster Lane shall be design and constructed as a perpendicular intersection. 3. All private drive isles shall have a minimum width of 26’ and meet Caldwell Fire Department requirements, whichever is greater. Street 1. Full street improvements shall be completed to all classified roads adjacent to the proposed project (including Laster Lane) in accordance with all City of Caldwell standards and specifications. Improvements shall include (but are not limited to) curb, gutter, sidewalk, asphalt, streetlights, joint trench, spare communication conduit along classified roadways, storm drainage facilities, etc. Road improvements shall include the section of Laster Lane from the sites proposed north access point to the existing Laster Lane paved road section to the west. Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 4 of 8 2. Any access proposed on the south of this development over the Notus Canal shall be for emergency access only. 3. Emergency access shall meet all Caldwell Fire Department requirements. 4. All private driveways/drive isles shall fully comply with City of Caldwell standards and be approved by the Caldwell Fire Marshall. 5. No lot/building shall have direct access to/from Laster Lane. 6. Applicant shall coordinate with the United States Postal System to determine a cluster mailbox unit location. Said location shall be interior to the site and shall be located in a manner that will not impact, or cause queueing onto, Laster Lane said location shall be approved by the Engineering Department during construction drawing plan review and prior to plan approval. Traffic Mitigation The following are the required traffic related mitigation measures for the Lavender Crossing Apartments development resulting from the traffic impact study performed by CR Engineering, Inc. dated 12-2-2021 pursuant to City Code Chapter 10, Article 10. A traffic impact study will be required for this development because of the volume of traffic produced. 1. Provide a cross-access easement allowing use of approaches and cross-access of the site by both onsite and adjacent development. A copy of this easement shall be provided to the City prior to issuance of any Certificate of Occupancy. 2. Community Planning Association of Southwest Idaho has computed the average trip length in Canyon County to be 7.3 mi. Traffic impact mitigation should presumably occur at both trip ends so ½ of the trip length should be attributed to each end. It is estimated that trips will encounter a major intersection every half mile along any given path. The capacity of an average fully improved intersection (assumed to be the intersection of a collector and an arterial road) is estimated to be 5,080 vehicles/hour. The estimated traffic resulting from the proposed density in this subdivision based on the most current Traffic Impact Analysis sets the pm peak hour traffic flow at 127 vehicles for the entire subdivision. Note: Mitigation requirements are subject to change based on revisions or updates that may be performed to the TIS by the traffic engineer during project plan review. Following the City of Caldwell’s mitigation equation ((127 veh/hr*7.3 mile/trip*0.5 trip ends*2inter/mi) / (5080veh/hr)) the total contribution of this development to traffic mitigation shall be 18.25% of a fully improved intersection. This percentage represents the total capacity utilized from each intersection (once fully improved and possibly signalized) encountered by trips generated over the development’s half of the generated trip length. a) The owner/developer/applicant shall design and construct roughly 18.25% of the signalization improvements needed for an average intersection, as defined, at one or more nearby (within 3.5 miles of the site) deficient locations to be determined by Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 5 of 8 Engineering staff. The Engineering staff shall have reasonable discretion to determine the sites of construction and what design and construction equals roughly 18.25% of the signalization improvements needed for an average intersection. Engineering staff can provide information about applications with whose mitigation efforts the owner/developer/applicant can combine to achieve even units of 100%. i) The owner/developer/applicant may be allowed, at his option, to contribute monies in lieu of construction to the City of Caldwell Roadway Trust Fund, but the basis for the obligation is for construction. Monetary contributions must be made at a level commensurate with costs to construct the same by the City and as estimated by the City. This alternate provision for payment of money is not a requirement, is for the benefit and convenience of the owner/developer/applicant only and does not constitute an Impact Fee. iii) The average cost of intersection is estimated at $425,000 for procurement of design services, construction, and associated costs by the City, of which 18.25% of that cost is what needs to be covered by this subdivision. Water 1. All on site water mains will need to be looped into existing mains and have a minimum of two points of connection for fire flow and water quality purposes. Internal main sizing and construction plan approval, will be dependent upon the availability of fire flow. 2. Applicant shall construct a 12” water mainline in Laster Lane along the project frontage and within roadway improvements, extending the existing water line from the west Laster main line to the site’s primary access. 3. Each buildable lot shall be supplied with potable water. If buildings are constructed to include individual units that could feasibly or will be sold separately, each unit shall be serviced separately 4. The location of water service, including sizing of mains, providing of easements, frontage construction, and offsite construction are to be decided during review of improvement plans. This development will be required to comply with the Water Master Study. Sanitary Sewer 1. It shall be the responsibility of the applicant’s engineer to verify that connection to existing sewer mainlines will not exceed the functional capacity of said mainlines. Provision for connectivity by future developments shall be met in accordance with current City standards. 2. The Developer will be required to extend the sewer mainline in Laster Lane to the proposed site access point for service into the site. Exact location details of said extension will be determined during the review of the improvement plans. All sewer mainlines shall meet city requirements for design and construction standards. 3. Each buildable lot shall be provided with individual sewer service. If buildings are constructed to include individual units that could feasibly or will be sold separately, each unit shall be serviced separately. Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 6 of 8 4. Any easements for sewer lines not in the right-of-way should be at a width sufficient to construct same and not less than 20 feet in width. Easements for adjacent sewer and water lines not in the right-of-way shall be at a width sufficient to construct the same and shall be no less than 30 feet in width. 5. A 20’ wide all-weather surfaces may be required to be constructed over mainlines that fall outside the public right-of-way. All weather surfaces shall be constructed sufficiently to support heavy equipment necessary to construct and maintain sewer under all seasonal weather conditions. Irrigation 1. Existing easements and/or right-of-ways for any irrigation facility shall be determined and clearly indicated on the construction plans. Construction across or re-routing of these facilities is subject to approval by the Pioneer Irrigation District and at their discretion or their assigns. 2. The Developer shall maintain any existing upstream drainage rights and downstream irrigation rights across the property. During the design phase of this project, the developer or his engineer is to contact the appropriate irrigation district to help ascertain these rights. Appropriate facilities shall be provided by the developer to convey irrigation and drainage water across the property to take care of these offsite needs. There is to be no discharge of gravity/pressure irrigation return water into the projects storm water system. 2. The development is to include a non-potable water pressure irrigation system. The design of this pressure irrigation system is to be reviewed and approved by the Caldwell Municipal Irrigation District prior to construction plan approval. It shall be required that the system will be operated and maintained by the Caldwell Municipal Irrigation District. 3. Each lot, or building area, shall be provided with a pressure irrigation service in compliance with Caldwell Municipal Irrigation District standards. 4. All pressure irrigation mainlines shall be located in the public right-of-way or within a public utility easement, with a minimum width of 10 feet, centered over said mainlines as per current City standards. 5. Applicant shall place the pump station in an area that is easily accessible with a recorded perpetual easement sufficient for convenient access and maintenance of said pump station. The lot shall be owned and maintained by the home owners association. 6. The applicant shall ensure that an adequate continuous irrigation supply flow is available to meet the pressure irrigation system requirements of CMID. 7. The applicant shall transfer a proportionate share of any existing water right(s), except those held in trust by an irrigation district, to the City of Caldwell for both irrigation and domestic water Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 7 of 8 supply for the subject development. If this should occur, The City shall assist in registering the transfer. 8. The proposed development may utilize an existing pressure irrigation pump station with approvals from Caldwell Municipal Irrigation District. Any upgrades to the pump station necessary to supply the proposed development with pressurized irrigation water is the responsibility of the Applicant. Should Applicant connect to this pump station they shall supply the City of Caldwell with a water model of the whole pressurized irrigation system showing that the system design meets all Caldwell Municipal Irrigation District standards. 9. All plans and construction drawings submitted to the City of Caldwell for review and approval for any out-of-season irrigation work to be performed within or across facilities located within (or owned by) irrigation districts other than CMID shall be submitted to the Caldwell Engineering Department no later than August 15th. Submittal of plans after this date may result in Applicant not receiving plan approval in time to complete out-of-season work. 10. In conjunction with Laster Lane improvements, Applicant shall coordinate with Pioneer Irrigation District on the relocation of the Highline Canal as needed for the construction of Laster Lane. Developer is responsible for all relocation requirements necessary for and in conjunction with the road improvements required for this development. Storm Drain 1. As noted previously, provision is to be made for the disposal of stormwater drainage in accordance with the City Stormwater Management Manual and any updates adopted subsequent to this application. It is to be noted that retention designs will be denied in most instances. A copy of this policy is available upon request. The engineer of record is to provide calculations, which indicate that the assumptions in his stormwater drainage plan comply with the requirements of the stormwater manual. In this case, if a storm water system is existing, the burden of proof is on the developer to verify the capacity is sufficient for the proposed development. 2. The applicant shall identify and retain all historical drainage discharge points from the property for the purpose of draining on-site storm water detention facilities. 3. Storm water detention basins are required to remain on-site and are to be operated and maintained by the Applicant/business owners association/etc. 4. There is to be no discharge of storm water overflow into any irrigation water return/discharge facility/ditch/pipe/etc. Building Permits 1. Prior to submission of building permits, public utilities and infrastructure must be completed or an appropriate construction security provided. A 20% temporary restriction in the issuance of building permits will be enforced until all utility construction has been completed, inspected, tested, approved by the City and certified by the Applicants engineer; including completion all punch list items. Lavender Crossing Subdivision ANN23-000007, SUP23-000004 Page 8 of 8 2. Applicant shall submit an electronic (dwg.) copy of the project site plan suitable for mapping and addressing purposes no later than 30 days prior to submission of the first building permit.