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HomeMy WebLinkAbout4.b. Ardan Place FP EXECUTIVE SUMMARY Planning Commission Meeting Date: February 23, 2021 Tentative City Council Meeting Date: March 16, 2021 AGENDA ITEM: 21-04-FP Request by Tamarack Land Development for Final Plat Approval of Ardan Place. AGENDA SECTION: Consent PREPARED BY: Kyle Klatt, Senior Planner AGENDA NO. 4.b. ATTACHMENTS: Location Map; Preliminary Plat Area; Final Plat; Cover Sheet, Site Survey, Grading Plan, Storm Water Plan, Tree Inventory, Tree Preservation Plan, Utility Plan, Street Light and Signage Plan, Landscape Plan, Engineer Review Memo APPROVED BY: KL RECOMMENDED ACTION: Motion to recommend that the City Council approve the Final Plat for Ardan Place subject to the following conditions: 1. Execution of a Subdivision Agreement. 2. Extension of the temporary cul-de-sac at western end of street running east and west between Blocks 1 and 2 so it does not encroach into adjacent private lots. 3. The City Engineer must approve a final turn-around design for the southern terminus of Ardroe Avenue at its intersection with the private street serving the townhouses and future school site. 4. The final plat shall include all easements as requested by City. 5. Provision of $62,040 for landscaping surety. 6. Payment of $299,550 for Fee-In-Lieu of Park Dedication. 7. Completion of the private dog park with the phase two improvements. 8. Elimination of dedicated public street right-of-way for all streets providing access to townhouses and inclusion of the private street within a separate outlot or combined with an adjacent existing outlot. 9. Provision of drainage and utility easements over all utilities within private roads or common open space areas. 10. Trail easements shall be provided to city over the multi-use trail. 11. Easements shall be provided over all temporary turn around areas within the subdivision. 12. Finalization of all easements required with the school district, including the turn- around area off of Ardroe Avenue and all easements needed for construction grading and access. 13. Removal of the existing barb wire and snow fencing along the railroad right-of-way. 14. Adherence with conditions of preliminary plat and master development plan approvals. 15. Compliance with all other conditions and standards within the City Engineer’s Memorandum dated January 29, 2021. 2 SUMMARY Applicant: Tamarack Land Development (Developer/Applicant); D.R. Horton, Inc. Minnesota (Builder) Comp. Guide Plan Designation: LDR – Low Density Residential Current Zoning: R1 PUD/R2 PUD – Low and Moderate Density Residential (Ardan Place Planned Unit Development) Gross Area: 25.4 Acres (Phase 1 including ROW); 52.2 Acres Overall Net Area: 23.9 Acres Lots/Units: 42 Single Family Lots/55 Townhouse Lots (97 Total Units) Gross Density: 1.86 units/acre Net (Met Council) Density: 4.06 units/acre The Planning Commission is being asked to consider a request from Tamarack Land Development for approval of a final plat for Ardan Place to allow development of 42 single-family and 55 townhouse lots. The proposed plat represents the first of two eventual phases associated with the Ardan Place Planned Unit Development (PUD) approved by the City last year. The final plat is necessary to facilitate subdivision of the subject property into individual residential lots, outlots, and public streets. Staff finds the application consistent with the Ardan Place Preliminary Plat and Master PUD Development Plan and recommends approval of this application subject to the conditions detailed in the attachments and the motion above. BACKGROUND In November of 2020, the City Council approved a preliminary plat, PUD master development plan with rezoning, and zoning ordinance amendment for Ardan Place, which was comprised of 79 single-family lots and 135 townhouse units on property located approximately one-quarter mile west of Akron Avenue and along the south side of Bonaire Path. The subdivision will be situated between a new elementary school site to the east, the Meadows of Bloomfield neighborhood to the west, and Union Pacific Railroad right- of-way to the south. The applicant is proposing to final plat the overall subdivision in two phases divided roughly in half from east to west starting on the eastern side next to the elementary school site. In addition to the lots platted within the phase one area, the applicant will be dedicating right-of-way for the internal and adjacent street system and platting two larger outlots (Outlots A and B) set aside for development of phase two of Ardan Place. The construction plans for the subdivision have been prepared to follow the location of the two planned development stages, adhering to the mass grading plan and street layout approved with the preliminary plat. The phasing works well because it allows the connection between the single-family and townhouses areas to be completed with the initial final plat and permits the storm water plan can be constructed in two phases from east to west as well. Public utilities are available to serve the eastern half of the property without a connection into existing systems serving the Meadows of Bloomfield neighborhood to the west. The second project phase will include all necessary connections to loop the system into existing adjacent developments. ISSUE ANALYSIS Legal Authority . This application is a Quasi-Judicial action. The final plat application is Quasi-Judicial because the City has a set of standards and requirements for reviewing this type of application that is described in detail below. Generally, if the final plat meets the ordinance requirements it must be approved. Land Use and Zoning . The proposed 42-lot single family and 55-unit townhouse final plat is consistent 3 with the current land use and zoning classifications (as amended last year with the preliminary plat). The subject property is guided LDR – Low Density Residential and is now split between two zoning districts: R-1PUD and R-2PUD, Low and Medium Density Residential Planned Unit Development. Both districts are considered appropriate under the land use guidance, with the R-1 area covering the northern portion of site and R-2 area following a private road south of the single-family lots. As a result of the City’s previous approvals, the property is subject to the standards of the R-1 (single-family areas) and R-2 (townhouses) zoning districts as well as the standards for the entire subdivision documented the approved PUD. Through the PUD process, the developer requested and was granted flexibility from certain requirements of the zoning ordinance; the most notable deviations are listed below. All these items were anticipated in the preliminary plat approval and were part of the initial PUD approval. • Section 11-4-5 F. 1. R-1 Minimum Lot Area: The minimum lot area shall be 8,000 square feet (10,500 square feet for corner lots). • Section 11-4-5 F. 2. R-1 Minimum Lot Width: The minimum lot width shall be 65 feet (75 feet for corner lots). • Section 11-4-5 F. 4. R-1 Minimum Front Yard Setback: The minimum front yard setback shall be 25 feet. • Section 11-4-5 F. 5. R-1 Minimum Side Yard Setback: The minimum side yard setback shall be 7.5 feet. • Section 11-6-3 E.10: The required tree replacement is 728 caliper inches (which is in addition to the base zoning district landscaping requirement of one tree per lot). • Section 11-4-5 F. 9. R-1 Maximum Lot Coverage: The maximum lot coverage shall be 40% for lots below 10,000 square feet and 30% for lots over 10,000 square feet. The proposed final plan and final development plans follow the preliminary plat closely and will meet all applicable zoning standards with the PUD exceptions noted above. Impervious Surface Coverage Since the preliminary plat approval, the developer has spent some time examining the potential impervious surface coverage for each of the lots based on the typical home plans that will be offered within Ardan Place. As a result of this review, the developer believes that several of their homes may be difficult to construct under the lot coverage requirements of 30% or 40% as approved by the City. All home plans will fit within the individual lots in terms of width, depth, setbacks, and other variables; however, once all potential hard surfaces are considered (house pad, driveways, patios, and sidewalks), some lots will exceed the maximum thresholds allowed in the PUD. The developer is asking that the City approve a standard more consistent with the Caramore Crossing, Meadow Ridge, and Dunmore developments which allowed a 35% to 45% impervious coverage maximum based on the size of the lot. Staff has considered the request and is recommending approval of a lot coverage standard allowing a 35% maximum lot coverage for lots larger than 10,000 square feet and 45% for lots smaller than 10,000 square feet. Because this change would not alter the number of approved lots or the overall project density in any manner, it is considered a minor PUD changes that could be approved by the City Council. This recommendation is noted as a condition of plat approval and would be presented to the Council as part of the Commission’s final plat review. During this discussion staff has found some variability in hard surface coverage requirements for many of the recent neighborhoods. A more standardized approach to new development may be warranted. Most of these neighborhoods are single family and most likely should be held to the same standard, regardless of developer. Another topic for further conversation is setting a minimum lot size for the small lot PUD’s. Staff’s position has been that the developer is platting lots that accommodate their homes styles. After the fact, developers come to the City requesting variations from the approved standards because not all their 4 model homes fit on the smaller lots. The discussion needs to be had up front that the sizes meet their needs, as part of the initial review and approvals. Final Plat. Standards for reviewing subdivision requests are detailed in Title 12 of the Rosemount City Code. This section of the Code outlines the two-step Preliminary and Final Plat process for land subdivision. In this case, the preliminary plat was approved in November of 2020 consisting of 215 single- family and townhouse lots and various outlots. The Ardan Place final plat will subdivide the existing unplatted land into 42 single-family lots, 55 townhouse lots, two large outlots that will be further platted into residential lots in the future, dedicated right-of-way for all subdivision pubic roads, and two outlots for storm water ponding and common areas around individual townhomes. Please note that the final plat indicates that the townhouse street would be dedicated as public right-of-way; however, the City has required that this road remain private and therefore it should be platted as a separate outlot or combined with one of the adjoining outlots surrounding the townhouses. Streets & Access. The overall plans for the subdivision include access to Bonaire Path West from the existing Autumn Path connection at the west side of the preliminary plat area and via a new extension of Ardroe Avenue from the east side. The final plat will therefore include construction of the eastern access and extension of Ardroe Avenue in addition to the interior roads servicing the eastern single-family and townhouse areas. All streets providing access to single-family lots will be public, while all townhouses will front onto a private street system. The final plat area does include a connection between the private and public street sections in the middle portion of the subdivision, and this street segment should also be private and outside of a dedicated right-of-way. Since the preliminary plat approval, the plans have been updated to accurately align with the configuration of Ardroe Avenue presently under construction on the north side of Bonaire Path West. The two public streets that will continue west into the phase two plat area will be constructed with temporary cul-de-sacs at western edge of the final plat area. A condition of approval notes that the cul-de-sacs should be kept out of the any private buildable lot area. Water and Sanitary Sewer. Public utilities serving the subdivision will connect into the sanitary sewer and water lines currently located within the Bonaire Path West right-of-way. These services will follow the dedicated public street or private alignments and will be stubbed for further extensions to the west with the second addition. A small portion of the phase two sewer line will connect into the existing infrastructure in the Meadows of Bloomfield development, while the water lines will be looped into this adjacent system and back out to Bonaire Path from Autumn Path. Drainage and utility easements must be provided on the plat for those lines that run underneath the private townhouse roads. Landscaping and Berming . Prior to preliminary plat approval by the City Council, the applicant updated the tree preservation and replacement plan to save an existing heritage tree (defined by tree type and size) and some other significant trees along the western property boundary. In order to accommodate reduced grading and disturbance in this area, some of the townhouses have been reconfigured to provide more room along the lot line. These changes are reflected in the updated overall project plans for the subdivision, but are outside of the area included in the final plat (this area will be further reviewed when the second project phase moves forward). In addition to saving a small number of existing trees, the applicant was also required to increase the overall amount of caliper inches being replaced within the project. The landscape plan has been updated to address the preliminary plat conditions and now includes 729 caliper inches of replacement trees (an increase of roughly 50 caliper inches from the previous plans). Along with this modest increase in replacement trees, the landscape plan continues to provide the required number of trees for development within an R-1 and R-2 zoning district based on the number of overall buildable lots with the subdivision. Overall the first subdivision phase includes 188 trees (just under half of the trees planned for the entire subdivision) comprised of a mix trees on individual lots and replacement trees within common open space areas. At $300 per tree based on the City fee schedule the required landscaping security totals $62,040 5 (188 trees plus 10%). Storm Water Management. The proposed storm water management system consists of catch basis, storm water pipe, and infiltration and retention basins located along the southern property line and will be constructed in two stages following final plat boundary running through the middle of the property. The western-most storm water retention basin will be sized to meet the storm water requirements for the final plat area; however, once the next phase is constructed it will be reduced in size as more infiltration and retention areas are constructed within phase two. The reduction in area will allow the developer to regrade a part of this area to accommodate the planned dog park. The City Engineer has reviewed the surface water management plans for the site and has noted several minor modifications and updates that will need to be addressed by the developer in the attached review letter. Grading . The grading plans adhere to the overall grading plans approved with the Ardan Place preliminary plat. As noted in the preceding section, an area for the private dog park will be regraded with the next project phase and with the construction of additional storm water ponding areas further to the west. In order to construct the new extension of Ardroe Avenue, which crosses into the adjacent school district site, the applicant will need to secure easements from the school district for the road and related grading adjacent to the road. Draft easements have been submitted with the final plat and will need to be finalized prior to release of the plat for recording. Parks and Open Space. Parks and Recreation staff reviewed the plans for final plat of Ardan Place and found them to be consistent with the preliminary approval. The City is not planning on any public parks within the subdivision area, and staff is recommending that the City collect cash in-lieu of land for the 97 units. This amount totals $299,550 (42 single family units at $3400 per unit and 55 townhouse units at $2,850). The proposed dog park is a private open space amenity for the neighborhood and will not be controlled or maintained by the City in any manner. The dog park will be constructed with the second phase of the project. Sidewalks, Trails, and Pathways . Consistent with the City’s policies for sidewalks in new subdivisions, the construction plans depict sidewalks along one side of all public streets, including the addition of a sidewalk along Ardroe Avenue connecting the townhouse area to Bonaire Path West. The plans also include a larger, multi-purpose bituminous trail along the southern edge of the townhouse area that will connect back to the sidewalk system at the eastern edge of the subdivision and along the private street connecting the townhouse and single-family areas. This middle trail connection will also provide direct access to the planned dog park for properties further to the north. Staff is still working to determine whether the bituminous trill will be able to connect into the Meadows of Bloomfield development, and this issue will need to be addressed before the second addition is considered by the City. Engineering Comments. The Project Engineer has reviewed the proposed Ardan Place final plat and has provided comments in the Engineer’s Memo dated January 29, 2021. Notable comments include: the developer will need to pay for the required area charges as specified in the City’s fee schedule, some existing street, drainage, and utility easements will need to be vacated before the plat can be recorded, expanded easements will be needed over certain lots, and the construction plans will need to be updated to address modifications requested by the City Engineer. Development fees as detailed in the Engineer’s 6 Memo are due with the final plat and subdivision agreement. CONCLUSION & RECOMMENDATION Staff recommends approval of the Final Plat for Ardan Place creating 42 single-family lots and 55 townhouse lots. This recommendation is based on the information submitted by the applicant, findings made in this report, and the conditions detailed in the attached memorandums. AILSBURY AVENUEAUTUMN PATHUNION PACIFIC RAILROADBONAIRE PATH W (COUNTY ROAD 38)L=130.68 R=2865.00 Δ=2°36'48"N85°22'32"W 319.43L=879.86R=11459.00Δ=4°23'58"N0°05'15"W 2039.49 N67°07'26"E 1437 .67 N0°00'02"W 1407.20DOGPARK 122465789101156789101413112324252627282931230DOGPARK12246578910115678910141311232425262728293123019-050 09/29/2020 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 1 1 SITE PLAN EXHIBIT DRAINAGE AND UTILITY EASEMENTS: LEGEND N12/10/2020 WENCKASSOCIATESARDAN PLACE S0°05'15"E 2036.74N0°00'02"W 1407.66N67°08'10"E 1437.54L=879.86 R=11459.00 Δ=4°23'58"CH=879.65 CHB=S87°34'31"EN85°22'32"W 319.43L=130.68 R=2865.00Δ=2°36'48"AUTUMN PATHOUTLOT ABONAIRE PATH W (COUNTY ROAD 38)INSET AINSET BΔΔΔΔΔOUTLOT BΔWENCKASSOCIATESLEGEND ARDAN PLACE N0°00'02"W 438.46OUTLOT BINSET BBLOCK 3BLOCK 2BLOCK 1BLOCK 4 STREET NAME1234 567891234567891012345678123456789101112131415ΔΔSTREET NAMESTREET NAME STREET NAMEΔSTREET NAMEΔΔWENCKASSOCIATESLEGEND ARDAN PLACEINSET A STREET NAMESTREET NAME1231234561234561234561234566543211234561234561234123456OUTLOT CINSET AOUTLOT DΔ567891011121314WENCKASSOCIATESLEGEND ARDAN PLACE 1 COVER SHEET N GOVERNING SPECIFICATIONS: PROJECT DIRECTORY LEGEND 19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 8 2 OF 10 FUTUREDOGPARK1224101156789101413112324312F U T U R E F U T U R EF U T U R EF U T U R E3 GRADING PLAN LEGEND N19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 8 BONAIRE PATH W (COUNTY ROAD 38)FUTUREDOGPARK1241156789101413112324312F U T U R E F U T U R EF U T U R E4 LEGEND NSTORM WATER POLLUTION PREVENTION PLAN PROJECT DIRECTORY 19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 8 5 REPLACEMENT CALCS TREE INVENTORY &19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 8 UNION PACIFIC RAILROADBONAIRE PATH W (COUNTY ROAD 38)FUTUREDOGPARK12411567891014131123312F U T U R E F U T U R EF U T U R E19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 86 TREE PRESERVATION PLAN N AUTUMN PATHUNION PACIFIC RAILROADBONAIRE PATH W (COUNTY ROAD 38)FUTUREDOGPARK122465789101156789101413112324252627282931230F U T U R E F U T U R EF U T U R EF U T U R EF U T U R E19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 223 COMPOSITE UTILITY PLAN LEGEND N” ”””“” “” “” ” BONAIRE PATH W (COUNTY ROAD 38)FUTUREDOGPARK1241156789101413112324312F U T U R E F U T U R EF U T U R E19-050 01/26/2021 ARDAN PLACE TAMARACK LAND DEVELOPMENT, LLC ROSEMOUNT, MN N CAMPION ENGINEERING SERVICES, INC. Civil Engineering Land Planning 224 SIGNAGE & STREET LIGHT PLAN LEGEND N F U T U R EF U T U R E F U T U R E F U T U R E F U T U R EAUTUMN PATHUNIO N P A C I F I C R A I L R O A D BONAIRE PATH W (COUN T Y R O A D 3 8 ) 1 2 2 4 6 5 7 8 9 10 11 5 6 7 8 9 10 14 13 11 23 24 25 26 27 28 29 3 12 30 c 2OFARDAN PLACE 1ST ADDITION ROSEMOUNT, MINNESOTA TAMARACK LAND DEVELOPMENT, LLC1-26-2021 JLT\TLM Name Reg. No.Date Revisions Date Designed Drawn Mendota Heights, MN 55120 2422 Enterprise Drive (651) 681-1914 Fax: 681-9488www.pioneereng.com LANDSCAPE ARCHITECTSLAND SURVEYORSLAND PLANNERSCIVIL ENGINEERS 1-26-2021 I hereby certify that this plan was prepared by me or under my direct supervision and that I am a duly Licensed Landscape Architect under the laws of the State of Minnesota 44763 Jennifer L. Thompson L1LANDSCAPE PLAN 01-PLAN-120203-SHEET-LAND JLT\TLM c 2OFARDAN PLACE ROSEMOUNT, MINNESOTA TAMARACK LAND DEVELOPMENT, LLC1-26-2021 JLT JLT Name Reg. No.Date Revisions Date Designed Drawn Mendota Heights, MN 55120 2422 Enterprise Drive (651) 681-1914 Fax: 681-9488www.pioneereng.com LANDSCAPE ARCHITECTSLAND SURVEYORSLAND PLANNERSCIVIL ENGINEERS 1-26-2021 I hereby certify that this plan was prepared by me or under my direct supervision and that I am a duly Licensed Landscape Architect under the laws of the State of Minnesota 44763 Jennifer L. Thompson L2LANDSCAPE PLAN K:\016934-000\Admin\Docs\Arden Place Phase One Constrution Plan Memo - DRAFT.docx Memorandum To: Anthony Nemcek, Planner CC: Kim Lindquist, Community Development Director Stacy Bodsberg, Planning & Personnel Secretary Brian Erickson, Director of Public Works/City Engineer From: Tim Hanson, WSB Engineering Consultant Stephanie Smith, Assistant City Engineer Date: January 29, 2021 Re: Ardan Place, Phase One Construction Plan – Engineering Review SUBMITTAL: The final plat and construction plans for Ardan Place have been submitted, they were prepared by Campion Engineering Services, Inc of Maple Plain, MN. The developer of the site is Tamarack Land Development, LLC. Engineering review comments were generated from the following plat documents included in the submittal consisting of: ▪ Final Plat ▪ ALTA/NPSPS Land Title Survey dated 2/17/2020 ▪ Grading, Drainage, & Erosion Control Plans dated 1/26/2021 ▪ Sanitary Sewer and Watermain Plans dated 1/26/2021 ▪ Street and Storm Sewer Plans dated 1/26/2021 ▪ Storm Water Pollution Prevention Plan dated 1/26/2021 ▪ Tree Preservation Plan dated 1/26/2021 ▪ Storm Water Management Plan dated 9/29/2020 GENERAL COMMENTS – FINAL PLAT: 1. The development Fees are indicated below based on the 2021 Schedule of Rates and Fees. These fees are due with the final plat and subdivision agreement. ▪ Sanitary Sewer Trunk Charge: $1075/acre ▪ Watermain Trunk Charge: $6500/acre ▪ Storm Sewer Trunk Charge: $6865/acre 2. The existing Street, Drainage and Utility Easements within Ardan Place must be vacated with the platting of the final plat. 3. Doc. 2442129 (Item #11) 4. Doc2433691 (Item #10) 5. The ponding area and access portion of Outlot D shall be dedicated to the City. 6. The bike trail shall have a permanent trail easement place over its alignment. 7. The easement width between block 7 and block 8 and between block 13 and 14 is not adequate for maintenance of the storm sewer pipe that extends between the blocks. 8. The D & U easement along the west lot line of Lot 1, Block 1 must be identified a s “10”. 9. The additional easement width at the corner of Lot 7, Block 1 is not shown on the construction plans. 10. Label “INSET B". 11. Provide temporary street easements for the temporary turnarounds. Anthony Nemcek 10/16/2020 Page 2 K:\016934-000\Admin\Docs\Arden Place Phase One Constrution Plan Memo - DRAFT.docx 12. The barb wire fence and plastic snow fence along the Union Pacific Railroad must be removed. SANITARY SEWER AND WATERMAIN 13. Sheet 3, Note 3, Sanitary Sewer & Watermain - Hydrants have an 8.5 foot bury. 14. Sheet 3, Add a note indicating service saddles for water services shall be installed on all corporation stops. 15. Sheet 5, The sanitary sewer run between MH1 and MH2 needs to be in bold line weight. 16. Sheet 5, The data for the existing MH is cut off. 17. Sheet 5, This sheet does not have the centerline stationing indicated. 18. Sheet 5, The” SEE DETAIL A” for the sewer run between MH1 and MH2 overwrites a platting leader line. The platting information can be removed from these sheets. 19. Sheet 5, The 12” X 8” Tee at station 0+18 will have to be a 12” X 12” Tee with two 8” Reducers. 20. All watermain sheets – the valve placements will be reviewed by Rosemount Utilities. 21. Number and locates of valves shall meet City of Rosemount Engineering Guidelines. 22. The bar scale on the construction sheets is not accurate. It should be 1” = 100’ 23. The notes for sanitary sewer service extension indicates the elevation is at 10 feet past the property line. Rosemount’s detail indicates the elevation is at 9 foot past the property line. Please correct/clarify. 24. Sheet 6,7,8 & 9, There are several riser lengths or location issues on these sheets. Sewer services need 2’ separation from the storm sewer, minimum. 25. Sheet 6, There are a couple of locations along the watermain alignment where it appears a 11 ¼ or 22 ½ degree bend should be noted. Please review. 26. Sheet 6, Add hydrant at the intersection of Street 3 and Street 4. 27. Sheet 6, Move the hydrant on Ardore Avenue to the intersection with Street 3. 28. Sheet 7, 9, do the sanitary sewer stubs (3) need a manhole shown in the future for staking and reference? 29. Sheet 7, Locate the hydrant on the lot line of Lots 4 & 5. 30. Sheet 8, The hydrant between the future lot lines in the temporary cul-de-sac could be moved one lot to the west. 31. Sheet 8, In addition to the note show the watermain lowered to 958.30 as it passes under the storm sewer at station 12+22. 32. Sheet 9, The sanitary invert for the west leg out of MH9 does not have a 0.1 drop indicated. 33. Sheet 9, Add a hydrant at the intersection of Street 4 and Street 3. 34. Sheet 10, The line weight for the watermain is not bold. 35. Sheet 11, The storm sewer at station 0+88 is not at the low point of the street profile. 36. Sheet 11, Ardore Avenue street alignment needs to be offset to avoid a electric pole on the north with its future extension. Was this completed. 37. Sheet 11, Provide a typical section for Ardore Avenue. 38. Sheet 11, A pedestrian access ramp is required on the east side of Ardore Avenue across from the pedestrian ramp on Street 3. 39. Several sheets and storm sewer runs, Storm sewer depth at structures in the street section need to be in excess of 3.5 feet in depth to minimize frost heaving of the street. 40. Several sheets and storm sewer leads, Show sanitary sewer and water service depth where the storm sewer crosses. 41. Sheet 12, Place structure STMH 2 in the curb line. 42. Sheet 12, The storm sewer at station 1+81 is not at the low point of the street profile. 43. Sheet 12, The storm sewer run between structures CBMH 6 and CBMH 9 is Detail E on sheet 17. Anthony Nemcek 10/16/2020 Page 3 K:\016934-000\Admin\Docs\Arden Place Phase One Constrution Plan Memo - DRAFT.docx 44. Sheet 12, The storm sewer run between structures CBMH 12 & CB 5 is Detail H on sheet 17, please label. 45. Sheet 12, Move STMH 3 to be 10 feet from the sanitary sewer line. 46. Sheet 12, The Centerline – Centerline data in the plan view and profile view are not the same. 47. Sheet 12, The horizontal curve of Street 3 is below a 30 MPH radius, approximately 22 MPH. 48. Sheet 12, Extend the length of the vertical curve at station 9+00 to 120 feet or more. 49. Sheet 13, The profile on Detail A is duplicated on sheet 12 for the portion east of CBMH 23. 50. Sheet 13, Placed structure STMH 9 in the curb line. 51. Sheet 14, Label the storm sewer run between CBMH 13A and CBMH 16A. DETAIL E, SHEET 17. 52. Sheet 14, Placed structure STMH 4 in the curb line. 53. Sheet 15, Label spot curb elevations of the parking bay. 54. Sheet 15, The storm sewer at station 2+00 is not at the low point of the street profile. 55. Sheet 15, Placed structure STMH 1 in the curb line. 56. Sheet 15, Bulkhead the storm sewer stub to the north on Street 4. 57. Sheet 15, Label the storm sewer run between CBMH 6 and CBMH 9. DETAIL G, SHEET 17. 58. Sheet 15, Label the storm sewer run between CBMH 10 and CB 4. DETAIL F, SHEET 17. 59. Sheet 16, Label the storm sewer run between CBMH 2 and CB 1. DETAIL A, SHEET 17. 60. Sheet 16, Provide a profile for the storm sewer run between the ponds. FES 2 – FES 3. 61. Sheet 16, Show the length of rip rap required to extend it to the bottom of the pond graphically. 62. Sheet 16. Label spot curb elevations of the parking bays. 63. Sheet 16, The storm sewer at station 18+16 is not at the low point of the street profile. 64. Sheet 16, Placed structure STMH 5 in the curb line. 65. Sheet 16, , Label the storm sewer run between CBMH 17 and CB 10. DETAIL G, SHEET 17. 66. Sheet 17, It would be nice to cross reference each profile with the plan sheet it is located. 67. Sheet 17, As previously noted, Show sanitary sewer and watermain locations at crossings. 68. Sheet 18, The contours have a bold line weight and a standard line weight, make them all standard. 69. Sheet 20, The weir wall in the pond outlet control structure has a single horizontal line that makes it appear there should be an aperture. Remove the line. 70. Sheet 22, The typical section details are washed out and blurry. 71. Provide a typical section for the private streets. STREETS AND SIDEWALKS Ardan Place consists of four local residential streets and two private streets. Access extends from Bonaire Path on a local street (Adore Avenue) that will also provide access to the school property to the east. A local street and a private street extend from Adore Avenue along the plat’s east boundary. These two streets extend west into the plat completing a loop within the plat.. Two local streets extend from the public street, terminating with temporary cul-de-sacs in the central portion of the posed plat. 72. Ardore Avenue extending from Bonaire Path is shared by the adjacent property to the east, property owned by the Independent School District 196 (ISD 196). The School Anthony Nemcek 10/16/2020 Page 4 K:\016934-000\Admin\Docs\Arden Place Phase One Constrution Plan Memo - DRAFT.docx District must grant an easement for the easterly portion of this street connection and acknowledge that this access will provide appropriate access for their site. 73. Coordinate southern end of Ardore Avenue with ISD 196 to provide a T-intersection allowing for bus turning movements into ISD 196 property. 74. Provide a 50 foot long street (pavement section) at the easterly terminus of Ardore Avenue for snow plow turnaround. 75. Stub streets shall be terminated with type 3 barricades (two at each terminus) with “Future thru Street” sign attached. 76. The temporary turnarounds are located on a portion of the platted lots and or boulevard of the platted lot, please move the temporary turn around off of the final platted area. 77. Grading east of Ardore Avenue will extend beyond the proposed easement area. LANDSCAPE PLAN 1. Sheet L1, Tree planting south of lot 3, block 4 is over the storm sewer line, 4 trees. 2. Sheet L1, Tree planting between block 7 and block 8 is too close to the storm sewer run. 3. Sheet L1, Tree planting between block 13 and block 14 is too close to the storm sewer run. INFILTRATION BASINS 78. Access to ponds and rear yard catchbasins should meet Engineering Guidelines and be shown on the plans. 79. Upon completion of the infiltration basin, the applicants Engineer shall complete infiltration testing and certify the functionality of the basin as needed. The city’s storm water consultant is reviewing the submittal, their comments on the plans and the Ardan Place Stormwater Management Report will be submitted shortly. G:\2021\Planning Cases\21-04-FP Tamarack Land - Ardan Place LLC Final Plat\Ardan Place - Minea Property Rosemount Stormwater Management Review - 02012021.docx 701 XENIA AVENUE S | SUITE 300 | MINNEAPOLIS, MN | 55416 | 763.541.4800 | WSBENG.COM Memorandum To: Brian Erickson, City of Rosemount From: Bill Alms, PE Laura Kivisto, EIT Date: February 1, 2021 Re: Ardan Place, Minea Property Plan Review WSB Project No. 016934-000 We have completed a secondary review of the documents provided by Campion Engineering Services on January 26, 2021 for the Ardan Place, Minea Property in Rosemount, MN. Documents reviewed include: • 19-050 Ardan Place 11x17.pdf, prepared by Campion Engineering Services, 1/26/2021 • 19-050 Ardan Place GRADING 11x17.pdf, prepared by Campion Engineering Services, 1/26/2021 • 20-0113 Geo Bundle – Final.pdf, prepared by Haugo Geotechnical Services, 3/18/2020 • 20-0113 Minea Infiltration Letter-Final.pdf, prepared by Haugo Geotechnical Services, 3/4/2019 • 210119_Ardan Place Stormwater Management Report.pdf, prepared by Civil Methods, Inc., 1/19/2021 • ARDAN PLACE STORM SEWER DESIGN.pdf, prepared by Campion Engineering Services, 1/13/2021 Applicant should provide responses to each comment. We offer the following comments below (greyed out comments have been addressed, comments in red are new to this review, and comments in standard text still apply). Grading, Drainage, and Erosion Control Comments: 1. General a. Show the lowest opening elevation of the proposed homes. b. Please provide a detail to clarify the house elevations. It was assumed that G stands for garage floor and LL stands for lower level or basement elevation. c. Label the driveway slopes. d. Show or define access routes for maintenance purposes to all inlets, outlets and manholes. The drainage and utility easements allow for access to the stormwater infrastructure over most of the site, but please provide clarity regarding the drainage and utility easement and access to the stormwater infrastructure on the south end of the site. e. Plans shall be signed by a licensed Professional Engineer. f. The proposed dog park is located within the infiltration basin on the grading plan, but outside the infiltration basin on the proposed drainage area map. Clarify the location. Stephanie Smith 02/01/2021 Page 2 G:\2021\Planning Cases\21-04-FP Tamarack Land - Ardan Place LLC Final Plat\Ardan Place - Minea Property Rosemount Stormwater Management Review - 02012021.docx i. Multi-use green space is considered acceptable, but fence locations and other components must be reviewed to reduce maintenance issues with the expected high water levels in the basin. 2. Ponds and Wetlands a. Please reference the Surface Water Management Plan pond number (1620) on the plan sheets. b. The 100-year HWL and 100-year snowmelt elevations differ by 0.1 between HydroCAD and the plans for the NURP basin and infiltration basin. Modify values to match. c. The NW I indicates a wetland to the east of the site that appears to be near the proposed roadway in the northeast corner of the site. Please show the wetland on the map and indicate that an adequate buffer distance is provided. d. NURP basins will be required to be lined. Please add a comment or detail to the plans indicating this. e. Request Ponds 1 and 2 be consolidated in the SW corner of the site and push the infiltration basin east. This will allow more efficient treatment and consolidation of maintenance of the NURP basins. i. How will the stormwater management for the future phase of the development tie into the Phase 1 system? 3. Emergency Overflow Routes: a. Label all rear yard and street low point EOFs. 4. Retaining Walls: a. No comments. 5. Erosion Control: a. An NPDES Permit is required. Please provide. b. Please provide a complete and accurate SWPPP including a narrative that complies with and includes all components of the NPDES permit. c. Provide an operations and maintenance plan for the stormwater system which identifies who is responsible for long-term maintenance. d. Where 10 or more acres drain to a common location, permittees must provide a temporary sediment basin that provides live storage for a calculated volume of runoff from a 2-year 24-hour storm from each acre drained to the basin. Temporary basins may be converted to permanent basins after construction is complete. Please indicate on plans. e. Ensure all proposed and existing catch basins that receive drainage are marked with inlet protection. In particular, consider CB-7. and the existing catch basins immediately outside of the work area. f. Include information about how the site will be stabilized. 6. Grading: a. Minimum slopes of 2% are allowed. There are several site locations that do not meet minimum grade requirements, in particular, the dog park. b. Show the limits of grading. In some cases, the proposed grades extend beyond the property boundary. Stormwater Management Plan: 1. General Storm Sewer Design Stephanie Smith 02/01/2021 Page 3 G:\2021\Planning Cases\21-04-FP Tamarack Land - Ardan Place LLC Final Plat\Ardan Place - Minea Property Rosemount Stormwater Management Review - 02012021.docx a. All storm sewer shall be designed to accommodate the 10-year rainfall event. Please submit rational calculations. i. Ensure pipe slopes and lengths match between the rational calculations and the plans. Several pipes were found that do not match (i.e. CBMH 20 – STMH 8, CB 11 – CBMH 19, STMH 4 – CBMH 14, CBMH 16A – CBMH 16, CBMH 7 – STMH 1, CBMH 5 – CBMH 4). ii. CBMH 16A – CBMH 16 is under capacity according to the rational calculations. b. The minimum storm sewer diameter shall be 15”. Currently, the storm sewer pipe from CB 1 to Ex. CB on the corner of Bonaire Path and Autumn Path is proposed to be a 12” RCP. c. Junction manholes should be designed to limit the hydraulic head increase by matching flow lines (0.1-foot drop across the structure for incoming and outgoing pipes of the same diameter and matching crowns for pipes with different diameters where feasible). d. Indicate quantity and size of riprap at the FES outlets. e. Insert the City of Rosemount Standard Detail SD 11, Trash Guard for Storm Sewer Aprons, into the plans. f. Indicate the casting type for the yard drains. g. 3-foot sump catch basins or manholes are required within the street just prior to discharging to a waterbody (CBMH-1). h. Provide call out or note to storm sewer sheets to reference sheet piling detail on flared end sections 24-inches or larger. i. Modify the low point roadway catch basin placement so the catch basins are located at the low points shown on the roadway profiles. j. Pond flared end sections shall be installed with half the pipe diameter below the NWL elevation unless directed otherwise by the City Engineer. As currently designed, the FES invert into the NURP basin is too low and should be raised to meet requirements. 2. Water Quantity a. Per past comments provided to the developer, provisions must be provided such as a regional outlet control structure to connect the overflows from the site to the east as shown in the City SWMP. i. An outlet control structure and a stub must be installed from the proposed regional basin 1620 to the property line, consistent with the CSWMP routing map and the snip below. Stephanie Smith 02/01/2021 Page 4 G:\2021\Planning Cases\21-04-FP Tamarack Land - Ardan Place LLC Final Plat\Ardan Place - Minea Property Rosemount Stormwater Management Review - 02012021.docx 3. Volume Control a. The NPDES permit indicates that infiltration is prohibited if the field measured infiltration rate is above 8.3 inches per hour. Field tested infiltration rate is about 30 inches per hour, but it is noted that soils will be amended to slow the infiltration rate to below 8.3 inches per hour. Please document this in the stormwater management report. 4. Freeboard a. Please provide 1.5 feet of freeboard between the EOF of the low lying rear yard drainage areas and the low opening of the homes (north side of site). 5. Water Quality a. No comments. 6. Easements a. No comments. 7. Modeling a. Recommend using a minimum time of concentration value of 7 minutes. b. Revise the area of Existing Subcatchment 3 to match between the HydroCAD model and area summary table. c. The proposed HydroCAD model labels shall match the proposed drainage area map. d. Modify the slope of the primary outlet pipe from the SW NURP Pond (Pond 2) in HydroCAD to match the detail shown on Plan Sheet 25. e. Because the HWL exceeds the RIM elevation of the OCS, include the horizontal opening in the HydroCAD calculations for the NURP basin. f. The 3.8 acres of adjacent site runoff to the NURP basin is not included in the HydroCAD model (states in stormwater management report that the offsite runoff enters the NURP pond). Please modify the HydroCAD calculations to include the offsite drainage. g. Modify the drainage area to the proposed NURP basin to include the future development areas that will be connected into the system via storm sewer at the north end of the site. 8. Flooding Concerns a. The berm is not shown to extend all the way around the perimeter of the NURP basin meaning that the 10-day snowmelt high water level will exceed the pond depth and flow to the east or potentially over the railroad tracks. Extend the contours on the plan sheet on the east and south sides of the site to determine any potential flooding impacts. Ensure that 100-year high water levels are not increasing within the railroad right of way along the south boarder of the site. i. In conjunction, model the capacity of the outlet pipe to convey the 10-day snowmelt event downstream.