Variance Staff Report St. Croix County Board of Adjustment Ben Hanke / Calda Donna LLC Hearing Date: January 20 & 21, 2016

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1 Applicant: Agent: Calda Donna LLC / Ben Hanke Bruce Lenzen Site Address: Salishan Drive Government Lots 1 and 2 Parcel ID #: Computer #: Site Location: Zoning District: Site Size: Requests: A-3 Variance Staff Report St. Croix County Board of Adjustment Ben Hanke / Calda Donna LLC Hearing Date: January 20 & 21, 2016 Government Lots 1 and 2, section 13, T28N, R20W, Town of Troy Rural Residential and Riverway Overlay District acres 1) Variance to the structure setback pursuant to Section G. 5.c.1) of the St. Croix County Zoning Ordinance. 2) Variance to the amount of fill extending beyond the limits of the structure pursuant to Section G. 3.b.1) 3) Variance to the 50 foot wetland setback pursuant to section G.2.a.2) 4) Variance to clear the vegetation located in the 200 foot ordinary high water mark setback pursuant to section H.8.e.1) Page 1

2 Exhibits: 1) Staff report 2) Hanke residential lot submission index dated August 3, a) Revised Site & Planting Plan submittals dated September 21, b) Revised Site Design & Vegetation submittals 11 by 17 format dated September 21, c) Revised Site Plan reflecting new wetland boundary submittals dated November 19, ) Certification letters from Marc Putnam and Roger Humphrey 4) Letter from Tom and Laura Schmitt 5) Letter from Ron Carlson 6) Letter from Heidi Kennedy. 7) DNR wetland concurrence letter 8) Easement Analysis 9) Hanke Presentation Booklet 10) Jeff White Value Impairment Report 11) Rich Dubay Letter 12) Staff Wenholz comments 13) Treequality Report Faith Appelquist 14) VonBriesen Memorandum Act 55 15) WDNR Endangered Resources Review 16) WDNR Wetland Concurrence Letter Page 2

3 BACKGROUND The applicant is the owner of a legal nonconforming 1.20 acre lot that was created on or before 1971 in the Lower St. Croix Riverway Overlay District in the Town of Troy. St. Croix County Zoning Ordinance, Sections Lower St. Croix Riverway Overlay District and Floodplain Overlay District, and St. Croix County Sanitary Ordinance, Chapter 12 applies. Note: This application is reviewed under the St. Croix County Zoning, Section Shoreland Overlay Districts, effective April 1, 2014; it includes shoreland, shoreland wetland and wetland overlay districts and is a complete update from the previous shoreland standards. Permitted Use - A single-family residence is permitted with a land use permit, per Section F. 2.a.1) Substandard Lot Determination Section I.4. This request is compliant with Section I.4. Substandard Lots and NR 118 since it was a lot of record before January 1, 1976 and the lot is in separate ownership from abutting lands. Unnamed Pond Determinations - WDNR Letter dated January 13, 2014: (Exhibit 6) The unnamed pond that is north of the proposed building site, has been determined by Heidi Kennedy, former WIDNR Shoreland Program Coordinator, to be a contiguous part of the St. Croix River, a backwater or slough and subject to all regulations of the St. Croix River Overlay Zoning District. Structure Setbacks Section G. 5.c.1) The proposed building site is 200 feet from the Ordinary High Water Mark (OHWM) of the main body of the St. Croix River. However, it is not 200 feet from the OHWM of the unnamed pond portion of the St. Croix River. Slope Preservation Zone Determinations, Section H.3.: The site plan has two-foot contours that staff reviewed and determined there are no slope preservation zones on this property. Staff conducted additional checks through onsite visits and confirmed that there are no slope preservation zones on the site. Page 3

4 Stormwater Plans H. 4., 5., 7. & 8. & I., J. & K. The total disturbed area identified in the application site plan is 9,700 square feet. No variation from this amount is allowed as the maximum disturbance standard is less than 10,000 square feet. Any increase in disturbed area requires additional review and permits. The submitted stormwater plan has been reviewed by Community Development Department staff. The plan does meet required infiltration standards. Prior to issuance of Land Use Permits, the stormwater plan will require additional review and revision to meet minimum NR151 performance standards and structural maintenance requirements. Upland stormwater run-on from the connecting access driveway needs further review prior to a determination of whether it meets DNR technical standards. Floodplain Determinations - Section The entire lot is in the floodplain. A HEC-RAS floodplain analysis has been completed by Brad Woznak a Professional Engineer and Certified Floodplain Manager with S.E.H. Engineering. HEC-RAS stands for Hydrologic Engineering Center (HEC) River Analysis System (RAS) and was designed by the US Department of Defense and Army Corps of Engineers to aid engineers in floodplain determination. One of the Floodplain requirements that study shows is that the proposed project will not raise or lower the regional floodplain elevation by the standard of 0.00 feet. The analysis completed by Brad Woznak was then reviewed and approved by Michael Rogney, DNR Water Regulations and Zoning Engineer and reviewed by Gary LePak, DNR Water Regulations and Zoning Engineer. This proposed project is in compliance with State Administrative Code NR 116, Wisconsin s Floodplain Management Program and Section of the Floodplain Overlay District. Based on the DNR s determination, construction of a residential structure is allowed if the structure is elevated on fill, which is two feet above the regional flood elevation. A Conditional Letter of Map Removal on Fill CLOMR-F is required before the fill is placed. After the fill is placed a Letter of Map Removal on Fill, LOMR-F is required. As part of the applicant applying to FEMA for a CLOMR-F, the local community needs to sign the community acknowledgement form. By the local community signing the community acknowledgment form, it verifies that the local standards to be removed from the floodplain are met. Page 4

5 Sanitary System St. Croix County Sanitary Chapter 12 and Wisconsin Department of Safety and Professional Services approval letter dated September 21, 2015 This is included in the Residential Lot Submission Index dated August 3 rd, (Exhibit 2) An individual site design by a licensed sanitary system designer was completed for this site. This designed sanitary system has been approved by the Wisconsin Department of Safety and Professional Services (WDSPS). WDSPS has granted a variance to allow the structure to be placed 5 feet from the residence. County staff have reviewed and the system is in compliance with Chapter 12. House plans - See page A-1 and A-2 of the Residential Lot Submission Index dated August 3 rd 2015: (Exhibit 2) The proposed house will be two stories, 28 feet high and will have a 1869 square foot footprint. Wetland Delineation Wisconsin DNR letter: (Exhibit 7) A wetland delineation was completed by Kelly Bopray of Bopray Environmental on July 1, 2013 for the applicant. Mark Harings and Tom Nedland from the WI DNR along with Greg Larson from the Army Corps of Engineers and Community Development Staff conducted an onsite review of the wetland delineation on October 29, A new wetland boundary was set by the DNR that concurred with the applicant s delineation and was used during the site planning process to place the house and fill outside of the wetland boundary. The proposed house, retaining wall and associated fill do not meet the 50-foot wetland setback required in Section G.2.a.2) Shoreland Overlay District. A variance to this standard is one of the variance requests. Geotechnical Investigation: Soil borings were completed to determine if the subsoils could support the proposed house. The soil borings revealed dark, organic soils from 2 feet deep to 6 feet deep. The applicant s Professional Engineer, Marty Gray with Haugo Geotechnical Services, recommended that this dark organic soil be replaced with suitable fill to support the footings of the proposed house. The application site plan includes excavating this organic material and replacing it with suitable fill. Page 5

6 Color illustration of water s edge, wetlands and setbacks. Proposed house and building pad. Page 6

7 AGENCY REVIEW Wisconsin DNR: Wisconsin DNR comments will be presented at the hearing. Town of Troy: Town of Troy comments will be presented at the hearing. Page 7

8 Living Wall: A living wall design example that will be used for a portion of the retaining wall. Living wall Living wall Page 8

9 Planting Plan: The dark green and brown circles represent vegetation that is proposed to be planted. The vegetation to be removed is not shown. Page 9

10 Variance 1) Riverway Section G.5.c.1) requires that structures are setback 200 feet from the ordinary high water mark (OHWM). This variance request is to construct a retaining wall feet from the OHWM and a house that is 44.2 feet from the OHWM of the pond that is located north of the lot. The 44.2 feet is to the eave of the structure. Ordinary high water mark of pond and dimensions to retaining wall and house. Retaining wall Page 10

11 Variance 2) Floodplain Section G. 3.b.1) requires fill to extend 15 feet horizontally from the structure foundation. This variance request is to have a minimum of 10.4 feet of horizontal fill from the structure. The Federal Emergency Management Agency (FEMA) requires the fill around the house to extend 20 feet from the foundation to protect the structure from flood damage. If an applicant cannot meet this standard one of their options is to have a Professional Engineer or some other design professional submit a professional certification that this structure will be reasonably safe from flooding according to the criteria in FEMA technical bulletin titled Ensuring that structures built on fill or near special flood hazard areas are reasonably safe from flooding These certifications have been submitted by Roger Humphrey a Professional Engineer and Marc Putnam a registered Landscape Architect (Exhibit 3) 10.4 feet of horizontal fill does not meet the 15 feet required for stability to 13.2 feet of horizontal fill does not meet the 15 feet required for stability. Horizontal fill extends 15 feet or more beyond the foundation on the south and east side. Page 11

12 Diagram showing construction of retaining wall and the required 10 feet of fill Diagram showing construction of living wall and the required 7.5 to 10 feet of fill Page 12

13 Variance 3) Shoreland Section G.2.a.2) requires structures to setback 50 feet from wetlands. This request is to construct a retaining wall that is feet from the wetland boundary and to construct a house will be feet from the wetland boundary. The feet is to the eave of the structure. A wetland delineation was completed by Kelly Bopray of Bopray Environmental on July 1, 2013 for the applicant. Mark Harings and Tom Nedland from the WI DNR along with Greg Larson from the Army Corps of Engineers and Community Development Staff conducted an onsite review of the wetland delineation on October 29, A new wetland boundary was set by the DNR that concurred with the applicant s delineation and was used during the site planning process to place the house and fill outside of the wetland boundary. Wetland boundary and dimensions to retaining wall and house. Retaining wall Page 13

14 Variance 4) Riverway Section H.8.e.1) requires no disturbance of the vegetation within 200 feet of the OHWM. This request is to remove vegetation within 200 feet of the OHWM. The construction of this house will require several trees to be removed. This tree removal and associated filling will negatively impact the root zones of adjacent trees. Damage to the roots of Oak trees may cause Oak wilt. Approximate 10 foot zone showing associated tree root disturbance in red. Area in orange reflects subsurface area of fill and excavation and trees to be cut. Page 14

15 FINDINGS 1. The property is owned by Ben Hanke. The agent is Bruce Lenzen. 2. The site is located at Part of Government lots 1 and 2, Salishan Drive. Also described as section 13, T28N, R20W, in the Town of Troy. Parcel number The applicants submitted four variances to construct a house on the property referenced above, pursuant to section (6) (c) of the St. Croix County Zoning Ordinance. In order to qualify for a variance, the following three criteria must be met per case law, WI Statutes and Section (6) (c) of the St. Croix County Zoning Ordinance. 1. Unnecessary hardship 2. Unique property limitations 3. No harm to public interests To determine if these standard are met, the Board must consider the purpose of the Riverway and Shoreland Overlay Districts, then consider the short term, long term and cumulative effects of granting the variances. Subchapter III.V Section 17.36, St. Croix Lower St. Croix Riverway Overlay District. B. PURPOSE 1) Reduce the adverse effects of overcrowding and poorly planned shoreline development. o This project will require an encroachment on the ordinary high water mark setback by placing the house within the 200-foot setback; this results in poorly planned shoreline development. 2) Preventing soil erosion and pollution and contamination of surface and groundwater. o This project is on fill to move the proposed structures above the flood elevation; however the stormwater management design provides only partial treatment of runoff within the infiltration cells and drain tile which are placed entirely on fill. Runoff and floodwaters overflowing from the treatment cells will be added to the saturated soils on the lot. These saturated soils will not provide sufficient infiltration and treatment to prevent contamination of surface and groundwater. Residential pollutants include thermal, chlorides, oils, hydrocarbons and household chemicals. o This project is proposing to install a 24 inch culvert that will convey and concentrate upland runoff to the adjacent wetland and discharge to the St. Croix River unnamed pond. o If the pervious pavers are not maintained according to the PaveDrain s maintenance requirements the stormwater treatment systems fails rapidly and causes extensive surface runoff. The PaveDrain Manufacturer s Page 15

16 recommended maintenance includes twice yearly vacuuming of the pavers to remove sediment that blocks the drainage function and regular herbicide applications. Herbicide applications are not allowed in the Riverway Overlay District except for invasive species control. 3) Providing sufficient space on lots for sanitary facilities. o This project requires a five foot variance from the absorption field to the residence to allow sufficient space for the sanitary facilities. 4) Minimizing flood damage. 5) Maintaining property values. 6) Preserving and maintaining the exceptional scenic, cultural and natural characteristics of the water and related land. o This project removes approximately 9,900 square feet of tree and plant cover which would have a negative impact on the scenic and natural characteristics of the St. Croix River. Subchapter III Section 17.30, Shoreland Overlay District B. PURPOSE Controlling filling and grading to prevent soil erosion problems. o The filling and grading for this project will require dredging of material in order to remove organic soil layers in order to provide a suitable foundation. This dredging will be detrimental to the aquatic wildlife habitat and the disturbance of an area that is river bed for many months of the year. Preserving wetlands for groundwater recharge and to minimize runoff and soil erosion. o This project will encroach on the wetland setback and this will result have negative impacts on those wetlands. The 50 foot wetland setback is a critical area for shoreline and upland plants that provide food and cover for a variety of birds, amphibians, insects, and mammals above the water. This 50 foot buffer is part of a larger 300 foot buffer that extends inland from the ordinary high water mark. This 300 foot buffer is critical in maintaining water quality and is one of the reasons for additional regulatory requirements on shoreland projects in Wisconsin. Protecting spawning grounds, fish, aquatic life and wildlife habitat by preserving wetlands and controlling shoreline alterations, dredging and lagooning. o This project will require a variance to the wetland setback. These setbacks are in place to protect these environmentally sensitive areas. In addition, the construction of this house and the amount of fill required will result in significant shoreline alterations and will be detrimental to spawning grounds in the spring. Preserve and restore shoreland vegetation and natural scenic beauty by restricting the removal of shoreland cover, preventing encroachment of structures, controlling shoreland excavating. o This project will require the removal of shoreland cover, require shoreline excavating, and will require an encroachment of the structure on the ordinary high water mark. Page 16

17 Preventing flood damages by restoring floodplains and wetlands to increase floodwater storage. o This project will require filling in the flood fringe and will not increase the area for floodwater storage. Unnecessary hardship: In order for the property to qualify for an unnecessary hardship under the area variance criteria, the following criteria must be met; The owner must be prevented from using this property for any permitted use. Conformity with the restrictions must be unnecessarily burdensome. The property can be used for an open space or recreational use. The Federal Lower St. Croix River Act and the National Wild and Scenic Rivers Act; Wisconsin Statutes Wisconsin Lower St. Croix River Act and Wisconsin Administrative Code NR 118 established the Lower St. Croix River standards which St. Croix County administers and enforces under Section The hardship criteria is not met. Hardship due to unique property limitations: This property is not unique, there are other properties along the St. Croix River with similar physical limitations. No harm to public interests: The proposed project will result in the following: Negative impacts due to encroachment on the wetland buffer. o Negative impacts on the aquatic and terrestrial habitat. o Loss of aquatic spawning areas and terrestrial nesting areas. Increased development and runoff in the 300-foot buffer from the shoreline. The removal of shoreline vegetation and the resulting negative impact on shoreline aesthetics. The encroachment of structures on the ordinary high water mark. Poorly designed shoreline development requiring 4 variances to ordinance standards. Visual impact to neighboring properties viewsheds. The above impacts on the land, wildlife, water resources and the neighbors are a harm to the public interest. STAFF RECOMMENDATIONS All three of the variance criteria, identified above, must be met to grant each variance. Staff did not find that any of the required variance criteria have been met, and therefore recommend denial of all four variance requests. Page 17