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C-2. Code Amendments – Permeable Pavement (Chapters 1, 7, 18 & 20) Review classification of permeable pavement technologies Y C -2 0 CITY OF ClIANIIASSEN w 1 = Chanhassen is a Community for Life-Providing for Today and Planning for Tomorrow g Aza MEMORANDUM TO: Planning Commission FROM: Vanessa Strong, Water Resources Coordinator DATE: October 17, 2017 SUBJ: Pervious Paver Policy Proposed Motion: "The Chanhassen Planning Commission recommends that the City Council adopt the attached ordinance amending Chapters 1, 7, 18, and 20 of the Chanhassen City Code." BACKGROUND The Chanhassen City Council selected a review and potential update of the city's policy on pervious pavements in residential districts as a Key Fiscal Strategy for 2017. Staff contracted with Wenck Associates, Inc. to assist in determining the potential ramifications of modifying the city's existing policy. During the June 26, 2017 City Council Work Session, staff presented the results of the consultant's study and internal research to the City Council. Staff was directed draft an ordinance allowing for the use of permeable pavers located in low-density residential districts outside of the Shoreland Overlay District. During the September 25, 2017 City Council Work Session staff discussed the proposed ordinance and the City Council instructed staff to bring the proposal before the Planning Commission. DISCUSSION Annually, the city receives requests from residents that wish to install additional impervious surface on their property above the maximum impervious coverage allowed by code. The most common request is for patio and sidewalk usage. Traditional patios and sidewalks are impervious surfaces and contribute to flooding, erosion,water pollution, and other environmental issues. PH 952.227.1100• www.ci.chanhassen.mn.us• FX 952.227.1110 7700 MARKET BOULEVARD • PO BOX 147 • CHANHASSEN • MINNESOTA 55317 Planning Commission Pervious Paver Policy October 17, 2017 Page 2 of35 Since these structures count as lot coverage, these residents must either request a variance or abandon the proposed project. There are several purposes for regulating and limiting impervious surfaces. Traditional city planning, zoning, and code requirements set limits of impervious surfaces by land use classification to encourage infiltration and natural groundwater recharge,reduce urban flooding and solar heat gain, limit overall hardscape, and provide green space. Impervious surface is also a term and a tool used in stormwater management for the purpose of operating stormwater utility fee programs. Federal, state, and regional regulations have been enacted to manage stormwater in urbanized communities including but not limited to the requirements of the EPA Clean Water Act,National Pollution Discharge Elimination Systems (NPDES), and specifically Municipal Separate Storm Sewer Systems (MS4)requirements. Careful consideration must be given when developing a city-wide set of ordinances, engineering and maintenance standards for permeable interlocking concrete pavers (PICP)to ensure correct design, installation, lifetime maintenance and function without becoming an administrative or regulatory burden on staff or property owners. Pervious Pavers Defined The MPCA Stormwater Manual defines the more encompassing definition of permeable pavement as follows: Permeable pavements allow stormwater runoff to filter through surface voids into an underlying stone reservoir where it is temporarily stored and/or infiltrated. The most commonly used permeable pavement surfaces are pervious concrete,porous asphalt, and permeable interlocking concrete pavers (PICP). The Interlocking Concrete Pavement Institute(ICPI) describes permeable interlocking concrete pavements (PICP) as: PICP consists of solid concrete units molded with joints and/or openings that create an open area across the pavement surface. The openings allow water from storm events to flow freely through the surface into an open-graded base where it is collected and stored before it infiltrates into the underlying soils. For low-infiltration rate soils, drain pipes are often placed in the subbase to drain excess water, thereby functioning as a detention facility with some infiltration. Uses and Limitations of Permeable Interlocking Concrete Pavements (PICP) Stringent design, installation and maintenance is imperative to ensure proper performance. Staff is concerned that in residential areas,the systems may not be installed properly and not be maintained as needed. It is essential that these systems are designed in line with industry- accepted guidelines and installed by certified installers. Staff does not have the resources to check back to see if the permeable pavers are working as intended, therefore plans have to be submitted, approved, and a maintenance agreement signed. The maintenance agreement will Planning Commission Pervious Paver Policy October 17, 2017 Page 3 of 35 detail enforcement procedures. Additionally staff is concerned that increasing lot coverage may impact how the stormwater utility fee is calculated and assessed. PICP are typically used in areas with light traffic at commercial and residential sites such as low- speed roads,parking lots, driveways, sidewalks,plazas, and patios PICP has become the preferred permeable pavement option over pervious concrete and asphalt applications in recent years due in part to the use in smaller residential or retrofit applications, and lower material and installation costs and maintenance. Research has demonstrated that PICP is an effective method for reducing stormwater runoff and pollutants from urbanized areas. Properly designed,installed, and maintained PICP can have design life surface infiltration rates exceeding 100 in./hour according to industry literature. All the watershed management organizations (WMO) recognize permeable pavement as a viable best management practice(BMP) to reduce volume and pollution. Many offer cost-share opportunities for their installation. However, complicating factors in the blanket use of PICP in the city are the varying rules and standards across the WMOs pertaining to the design, installation, and maintenance of permeable pavement and PICP specifically. Each WMO has its own specific rules, standards, and exemptions. Staff has researched how other communities handle pervious pavers for residential use in hard cover surface considerations and presented those findings at previous Planning Commission meetings. The following tables describe the city's existing hardcover restrictions: 1) Hard Surface/Lot Coverage Percentage as PUD City Code (Chapter 20 -Zoning/Article VIII. Planned Unit Development District. Division 1.- Generally. Sec. 20-505 - Required general standards, (e)) illustrates by table the following: Hard surface coverage shall be limited as follows: Comprehensive Plan Designation Hard Surface Coverage (%) Low or medium density residential 30 High density residential 50 Office 70 Commercial (neighborhood or community) 70 Commercial (regional) 70 Industrial 70 Mixed use 70 According to Code, individual lots within PUD's may exceed these standards if the average Planning Commission Pervious Paver Policy October 17, 2017 Page 4of35 meets these standards. 2) Hard Surface/Lot Coverage Percentage by Land Use Classification Most directly related to the policy implications of addressing PICP, "maximum lot coverage" as a percent of the lot. Maximum Lot Coverage by Land Use Classification Land Use Classification by District Maximum Lot Coverage by Percentage "A-2"Agricultural Estate* 20 "RR" Rural Residential* 20 "RSF" Single-Family Residential* 25 "R-4" Mixed Low Density Residential* 30 "RLM" Residential Low and Medium Density* single-family dwelling, 35 two-family dwelling, 40 townhouse or multi-family dwelling 50 "R-8" Mixed Medium Density Residential* 35 "R-12" High Density Residential* 35 "R-16"High Density Residential* 50 "BN"Neighborhood Business 65 "BH" Highway and Business Services 65 "CBD" Central Business No maximum "CC" Community Commercial 70 "BG" General Business 70 "BF" Fringe Business 40 "OI" Office and Institutional 65 "IOP"Industrial Office Park 70 day care facilities 65 Shoreland Management District single-family residential 25 medium/high density residential 35 industrial zones within Lake Susan Shoreland District 70 *Please be apprised that City Code (Chapter 20-Zoning, Article IV. - Conditional Uses. Division 3. -Standards for Agricultural and Residential Districts. Sec 20-254. - Churches (4). states, "No more than 70 percent of the site is to be covered with impervious surface and the remainder is to be suitability landscaped in conformance with Article XXV." Planning Commission Pervious Paver Policy October 17, 2017 Page 5 of 35 Shoreland Management and Bluff Creek Overlay Districts would need to be addressed in a different manner if PICP are allowed. Due to the environmental sensitivity of these regions, staff is not recomending increasing the permitted lot coverage within these districts. Current City Code Definitions that Influence the Use of PICP A key issue that influences the use of PICP in the City Code is the varying definitions and regulations of impervious surface, hard surface coverage and lot coverage. City Code (Chapter 1- GENERAL PROVISIONS/Sec. 1-2. Rules of construction and definitions) defines impervious surface as: any material that substantially reduces or prevents the infiltration of stormwater. It shall include, but not be limited to, gravel driveways,parking area, buildings, and structures. City Code defines: A Hardcover as: the definition of impervious surface. A Lot coverage as: that portion or percentage of a lot that is covered by impervious surfaces. A Structures as: anything manufactured, built, constructed, erected, or a portion thereof which is normally attached to or positioned on land, whether temporary or permanent in character, including, but not limited to, buildings,fences, sheds, advertising signs, dog kennels, hard surface parking areas, boardwalks,playground equipment or concrete slabs. The terms "hard surface" and "hard surface coverage" are not defined within Sec. 102 Rules of construction and definitions,however the terms are interspersed throughout the Code. Current City Code that Influences the Use of PICP Relevant"hard surface" or"impervious surface"references and standards by zoning classification are cited here and in the Appendix. To ensure code changes are made to accommodate the use of PICP in the city, City Code sections should be thoroughly reviewed. City Code (Chapter 18 - Subdivisions, Article III. - Design Standards. Sec. 18-60. - Lots (j) states, Proposed house sizes shall be shown on the subdivision plan and shall be designed to accommodate residents' future house expansion(e.g.,porches) and accessory structures (e.g., decks and patios) as well as the driveway and sidewalks to building entrances. If house plans are not known,then a 60-foot by 60-foot building pad and a 30-foot wide access driveway shall be used. The maximum permitted impervious surface shall be calculated for each lot and the permitted houses and structures shall be limited to those sizes. Design, installation, and maintenance standards would be at the discretion of appropriate city staff. The MPCA Stormwater Manual suggests using the design, installation, and maintenance guidance for PICP as referenced by the Interlocking Concrete Pavement Institute(ICPI). The ICPI's website is www.icpi.org. It includes information for design professionals and installers Planning Commission Pervious Paver Policy October 17, 2017 Page 6 of 35 regarding industry standards and specifications, installation guidelines and maintenance. Many certified installers are available in the metro area. Staff will reference ICPI for design, installation, and maintenance guidance. Planning Department Review Planning staff has reviewed the findings from the research that has been completed. A brief discussion of the potential impact of allowing pavers, summary of their findings and Planning staff's recommendations are presented below. Intensity of Land Use Of particular concern is the impact that allowing pervious pavements could have the intensity of land use within the city. In the case of industrial and commercial districts,this would allow for larger parking lots and buildings. Staff examined a site within the Southwest Corporate Center that is limited to 70% lot coverage. If lot coverage was defined solely as impervious surface and pavers were not considered impervious surface, the owner could increase the parcel's maximum building size from about 268,000 square feet to approximately 329,000 square feet and reduce the greenspace on site from 30 percent to about 10.5 percent. This would create a substantially different visual impact for surrounding land users and increase the development's traffic impact. In residential areas, this would mean that by substituting traditional impervious surfaces with pervious pavers, a builder could construct a house where only roofed structures counted towards lot coverage. This would allow for the construction of homes with a substantially larger footprint, as lot coverage currently used for driveways and patios could all be allotted to the house, and would also make it easier for large sheds to be constructed on small residential lots. Staff examined a property on W. 65th Street zoned Residential-Single Family and determined that if lot coverage was defined solely as impervious surface, the owner could reduce the property from having 75% greenspace to approximately 40% greenspace. Staff conducted the same exercise for a property zoned Residential Low and Medium Density on Strawberry Lane and discovered that the lot's greenspace could be reduced from 65%to around 31%. In both cases, the owners would be able to add 320 plus square foot sheds in their rear yards. The size of these accessory structures, overall intensity of property use, and visual impression of these residences would be very different from what is currently typical for the city's small lot residential neighborhoods. Since the city uses lot coverage as a major tool for limiting the intensity of development and preserving onsite greenspace, any change that completely exempts a category of materials from counting towards lot coverage will have many unintended consequences. Summary Planning staff agrees that pervious pavers and other similar systems are proven technologies that are well suited for use in low traffic areas. Staff recognizes that the current lot coverage limits on residential properties were drafted partially with the intent of managing the water resources in those zoning districts; however, the lot coverage standards were also created to create a certain Planning Commission Pervious Paver Policy October 17, 2017 Page 7 of 35 neighborhood aesthetic and limit the intensity of land use within the city. Staff desires to balance these two considerations to accommodate technologies that allow homeowners to create stormwater neutral structures, without comprising the character of the city's residential neighborhoods or allowing for more intense development and land use. Recommendation Planning staff recommends that the following changes be made to the City Code if permeable pavers are approved: 1) Detached single family and twin home residential properties should be allowed a total lot coverage of X+5%* where X is the currently established maximum impervious lot coverage, and the 5%is pervious pavement lot coverage. To qualify as pervious, the system must be designed in compliance with standards established by the Interlocking Concrete Pavement Institute(ICPI) and installed by an ICPI certified installer.** 2) The use of permeable paver systems on multifamily residential, industrial, and commercial properties should continue to be addressed through the site plan review process. 3) The term "permeable pavement"be defined in the City Code. 4) The usage of the terms "lot cover", "impervious", and "hardcover" should be standardized throughout the Code. *To provide context that would allow a 15,000 square foot lot(minimum RSF lot size) to construct a 750 square foot(25' x 30')pervious paver patio in addition to the currently permitted 3,750 square feet(25%) of impervious lot coverage. **For other types of pervious surface technologies, a similarly credible organization's guidelines and appropriately certified installer could be substituted. ALTERNATIVES: 1) Do nothing. Maintain current policy and continue to treat permeable pavements as impervious surface. Amended code for consistent use of terms. 2) Amend Chapters 1, 7, 18, and 20 to allow for the use of pervious pavements in select residential districts. 3) Allow the use of pervious pavements in all districts. RECOMMENDATION: Alterative 2 allows homeowners the ability to take advantage of new technology,while minimizing the impact that allowing pervious pavers will have on stromwater and the intensity of property use within the city. To accomplish this staff recommends the following: 1. Staff recommends amending some existing definitions, clarifying that permeable interlocking concrete pavers (PICP) is not considered impervious surface and adding some new definitions. Furthermore,we recommend that code be amended as necessary to modify the use of the terms I Planning Commission Pervious Paver Policy October 17, 2017 Page 8 of 35 "hard surface," "impervious surface,""pervious surface," and"lot coverage"to permit the use of PICP. 2. Staff recommends that the City Code be amended to incorporate the limited use of permeable interlocking concrete pavers (PICP) for single family residential properties up to an additional 5% of pervious lot coverage. PICP would not be allowed for this use in shoreland and Bluff Creek Management zones,higher-density business, commercial, and industrial districts. PUDs will be addressed on an individual basis to meet the unique requirements of each development. 3. Staff recommends that the city require applicants to install PICP in accordance with installation standards recommended by the Interlocking Concrete Pavement Institute(ICPI), and that city staff refer to the PICP inspector's guide for project construction. 4. Staff recommends that applicants receiving a permit to use PICP be required to execute a recordable Maintenance Agreement setting forth maintenance requirements consistent with the ICPI recommendations. The maintenance agreement will also include enforcement procedures Staff proposes the following changes be made to the City Code: Sec. 1-2.—Rules of Construction and definitions Hardcover. See Impervious surface . Impervious surface means a surface that either prevents or retards the entry of water into the soil and causes water to run off the surface in greater quantities and at an increased rate of flow than prior to development. Examples include, but are not limited to, rooftops, storage areas, roads, sidewalks,patios, driveways, or parking lots made of concrete, asphalt, rock, or non-pervious pavement systems. (20) Lot coverage means that portion or percentage of a lot that is covered by impervious surfaces and pervious pavement. (20) Pervious pavement allows storm water runoff to filter though surface voids into an underlying stone reservoir where it is temporarily stored and/or infiltrated. Examples of this technology include, but are not limited to porous pavers and permeable interlocking concrete pavers (PICP). Structure means anything manufactured, built, constructed, erected, or a portion thereof which is normally attached to or positioned on land, whether temporary or permanent in character, including,but not limited to, buildings, fences, sheds, advertising signs, dog kennels, hard surface parking areas, boardwalks, playground equipment, patios, or concrete slabs. (7) 20) Sec. 7-19. - Plans and specifications. The building official may require that plans and specifications, required by the Minnesota State Building Code, include a survey of the lot upon which the proposed building or construction is to be done, prepared and attested by a registered surveyor. An original signature is required on the certificate of survey. The survey shall provide the following information unless otherwise approved by the administrative authority: (1) Scale of drawing and north arrow; (2) Legal description of property; Planning Commission Pervious Paver Policy October 17, 2017 Page 9 of 35 (3) Dimensions and bearing of front, rear and side property lines; (4) Front, rear and side yard setback dimensions of all proposed structures; (5) Location of all existing structures on the property, boulevards, streets and right-of- way, including but not limited to, sanitary and storm manholes, hydrants, catch basins, power poles, phone boxes, fences and any encroachments; (6) Outside dimensions of proposed structure(s) including decks, porches, retaining walls (include elevations at bottom of footing and top of wall), stoops, stairs, cantilevers, fireplaces,bay and bow windows, egress window wells; (7) Location of a benchmark stake established by the surveyor at the front setback line within 20 feet of the proposed structure. Maintenance of the benchmark stake once established by the surveyor shall be the responsibility of the permit applicant; (8) Location of stakes established by the surveyor on side property lines at: a. Front setback line. b. Front building line. c. Rear building line. The maintenance of these stakes once established by the surveyor shall be the responsibility of the permit applicant. (9) Location of first floor elevation of buildings on adjacent lots. Vacant adjacent lots shall be labeled as such; (10) Location of all easements of record, including but not limited to, tree preservation, wetland conservation, cross-access, etc.; (11) Existing and proposed elevations at the following locations: a. Each lot corner. b. Top of curb or centerline of roadway at each lot line extension. c. Center of proposed driveway at curb. d. Grade at corners of proposed structure. e. Lowest floor level, top of block, garage slab. (12) Indication of direction of surface water drainage by arrows and impervious surface calculations for the lot or parcel; (13) Tree removal, tree preservation and grading plan if required by the development contract; (14) Wetland boundaries with ordinary high water level and 100-year flood elevation if applicable; (15) Driveway grade (minimum-0.50 percent, maximum—ten percent); (16) All trees in excess of six inches in diameter (diameter measured at four feet above grade); (17) All custom-graded lots and lots deviating from the approved grading plan shall require an as-built survey submitted to the city prior to issuing a certificate of occupancy; (18) Wetland buffer areas and wetland or lake setback dimensions; (19) Other information as required by the city; Planning Commission Pervious Paver Policy October 17, 2017 Page 10 of 35 (20) Location and type of erosion and sediment control measures to be installed by permit holder. (21) Calculation of the amount and percentage of the lot coverage broken out by impervious surfaces and pervious pavement, if present. Sec. 18-57. - Streets. (a) Streets shall be dedicated on the plat to the public. The location and design of streets shall consider existing and planned streets, reasonable traffic circulation, topographic conditions, runoff of stormwater, public convenience and safety and the proposed land uses of property to be served. (b) Street right-of-way widths shall be consistent with the comprehensive plan and official map, and shall conform to county and state standards for trunk highways. If no such plans or standards are applicable, right-of-way and pavement widths shall not be less than the following: Right-of- Roadway/ Street Way Pavement Classifications Widths Width (feet) (feet) Minor arterial 100 36 Collector 80 36 Local street (rural residential) 60 24 Local street (urban residential) 60 31 Local street (commercial/industrial) 60 36 Cul-de-sac, turnaround radius (urban/residential) 60 45.5 Cul-de-sac,turnaround radius (rural residential) 60 40 Cul-de-sac,turnaround radius (commercial/industrial) 60 48 Private Street serving residential development with a density of less 30 1 20 than 4 units per acre Private Street serving residential development with a density equal to 40 24 or greater than 4 units per acre Private Street serving commercial, office, office industrial or mixed-use 40 26 development (c) Insofar as practical, streets shall intersect at right angles. In no case shall the angle formed by the intersection of two streets be less than 60 degrees. Intersections having more than four corners are prohibited. Planning Commission Pervious Paver Policy October 17, 2017 Page 11 of 35 (d) A tangent of at least 300 feet shall be introduced between reverse curves on arterial and collector streets. (e) When connecting street lines deflect from each other at one point by more than ten degrees they shall be connected by a curve with a radius adequate to ensure a sight distance within the right-of-way of not less than 500 feet for arterials, 300 feet for collectors, and 100 feet for all other streets. (f) Proper design shall consider required turning radius of vehicles for access points or entrances to and from a highway using standards adopted by the state department of transportation. (g) All centerline grades shall be at least five-tenths percent and shall not exceed five percent, for arterials and seven percent for all other streets and alleys. Whenever possible, grades within 30 feet of intersections or railroad crossings shall not exceed three percent. (h) Different connecting street grades shall be connected with vertical curves. Minimum length, in feet, of the vertical curves shall be 20 times the algebraic difference in the percentage of grade of the two adjacent slopes. (i) Local streets shall have a centerline offset of not less than 300 feet. Offset intersections shall be avoided. (j) The alignment shall discourage through traffic. (k) The length of the cul-de-sac shall be measured from the intersection of the cul-de-sac and street's centerlines to the center point of the cul-de-sac turnaround radius (see diagram below). The maximum length of a street terminating in a cul-de-sac shall be 800 feet. The city manager or their designee may approve a cul-de-sac exceeding 800 feet if they determine that one or more of the following necessitate a length in excess of 800 feet: (1) There are opportunities for a secondary access to adjacent properties in the future. The cul-de-sac must comply with the temporary cul-de-sac standards specified in subsection (t) of this section, and should address an identified system deficiency outlined in the transportation section of the city's comprehensive plan; (2) Topography which would require substantial grading and/or the loss of significant trees that would alter the physical character of the property and/or surrounding parcels. Planning Commission Pervious Paver Policy October 17, 2017 Page 12 of 35 Larter lrt ct turrarc •adiu_ j I I 7 LI isrL, mom�.pm WM rlrr<rrl:or.of cnarilrr (1) Where a proposed subdivision is adjacent to a limited access highway, arterial or collector street, there shall be no direct vehicular or pedestrian access from individual lots to such highways or streets. To the extent feasible access to arterial streets shall be at intervals of not less than one-fourth mile and through existing and established crossroads. Access along collector streets will be restricted and controlled on the final plat. (m) Half streets shall be prohibited except where it will be practical to require the dedication of the other half when the adjoining property is subdivided, in which case the dedication of a half street may be permitted or required. The probable length of time elapsing before dedication of the remainder shall be a factor considered in making this determination. (n) Public streets to be constructed in subdivisions located inside the metropolitan urban service area line, as identified in the city comprehensive plan shall be constructed to urban standards as prepared by the city engineer's office. Streets to be constructed in subdivisions located outside the metropolitan urban service area shall conform to the rural standard requirements as prepared by the city engineer's office. The construction of private streets is prohibited except as specified in subsection(p) of this section. (o) Private streets may be permitted in commercial, office, office industrial, residential with a density equal to or greater than four units per acre or mixed-use developments if the city finds the following conditions to exist: (1) The prevailing development pattern makes it unfeasible or inappropriate to constrict a public street. In making this determination the city may consider the location of existing property lines and homes, local or geographic conditions and the existence of wetlands. (2) After reviewing the surrounding area, it is concluded that an extension of the public street system is not required to serve other parcels in the area, improve access, or to provide a street system consistent with the comprehensive plan. Planning Commission Pervious Paver Policy October 17, 2017 Page 13 of 35 (3) The use of a private street will permit enhanced protection of the city's natural resources including wetlands and forested areas. (p) Private street standards. If the use of a private street is to be allowed, it shall be subject to the following standards: (1) The common sections of a private street serving two units or more in a development with a density of less than four units per acre must be built to a seven-ton design, paved to a width of 20 feet, utilize a maximum grade of ten percent, and provide a turnaround area acceptable to the fire marshal based upon guidelines provided by applicable fire codes. Private streets serving residential developments with a density equal to or greater than four units per acre shall be built to a seven-ton design, paved a minimum width of 24 feet, utilize a maximum grade of ten percent, and provide a turnaround acceptable to the fire marshal based on applicable fire codes. Private streets serving commercial, office, office industrial or mixed-use development shall be built to a nine-ton design, paved a minimum width of 26 feet, utilize a maximum grade of ten percent, and provide a turnaround area acceptable to the fire marshal based on guidelines provided by applicable fire codes. Private streets serving a residential component only, within a mixed-use development may be built to a seven-ton design, paved a minimum width of 24 feet, utilize a maximum grade of ten percent, and provide a turnaround acceptable to the fire marshal based on applicable fire codes. Plans for the street shall be submitted to the city engineer. Upon completion of the private street, the applicant shall submit a set of"as-built" plans signed by a registered civil engineer. (2) Private streets must be maintained in good condition and plowed within 24 hours of a snowfall greater than two inches. Covenants concerning maintenance shall be filed against all benefiting properties. Parking on the private street or otherwise blocking all or part of the private street shall be prohibited. (3) Private streets that are not usable by emergency vehicles because of obstructions, snow accumulation, or poor maintenance are a public safety hazard. The city may remedy such conditions and assess the cost back to the property pursuant to M.S. § 429.101, subd. 1(C). (4) The private street design shall include adequate drainage facilities to convey storm runoff which may require hydrologic calculations for a ten-year storm event. Private streets serving residential developments with a density equal to or greater than four units per acre, commercial, office, office industrial, or mixed-use districts, shall include concrete curb and gutter. (5) Street addresses or city-approved street name sign, if required, must be posted at the point where the private street intersects the public right-of-way. (6) The private street shall be designed to minimize impacts upon adjoining parcels. The city may require revised alignments, specific building orientation, increased setbacks, and landscaping to minimize impacts. An erosion control plan should be completed and approved prior to construction. (7) The private street serving residential development with a density of less than four units per acre, must be located within a strip of property at least 30 feet wide extending 1 Planning Commission Pervious Paver Policy October 17, 2017 Page 14of35 out to the public right-of-way or covered by a 30-foot wide easement that is permanently recorded over all benefited and impacted parcels. Neither the area within the easement for the private street, nor the impervious surface lot coverage of the private street shall be included within the calculation of the lot area or lot coverage of the lot in which the easement is located. Once the private street terminates, the area of the easement and impervious surface lot coverage of the driveway shall be included in the calculation of lot area and lot coverage for the lot. (8) Private streets serving residential development with a density equal to or greater than four units per acre, commercial, office, office industrial, or mixed-use districts, must be located within a strip of property at least 40 feet wide extending out to the public right- of-way or covered by a 40-foot wide easement that is permanently recorded over all benefited and impacted parcels. Neither the area within the easement for the private street, nor the impervious surface lot coverage of the private street shall be included within the calculation of the lot area or lot coverage of the lot in which the easement is located. Once the private street terminates, the area of the easement and impervious surface lot coverage of the driveway shall be included in the calculation of lot area and lot coverage for the lot. (9) Maintenance and repair of private utilities located within the private street shall be the responsibility of the benefiting property. (q) Private reserve strips controlling public access to streets shall be prohibited. (r) Flag lots may be permitted in residential districts with a density of less than four units per acre, if the criteria in variance section 18-22 are met and upon consideration of the following: (1) The prevailing development pattern makes it unfeasible or inappropriate to construct a public/private street. In making this determination, the city may consider the location of existing property lines and homes, local or geographic conditions and the existence of wetlands. (2) After reviewing the surrounding area, it is concluded that an extension of the public or a private street system is not required to serve other parcels in the area, improve access, or to provide a street system consistent with the comprehensive plan. (3) The use of a flag lot will permit enhanced protection of the city's natural resources, including wetlands and protected areas. (4) Sufficient open space is preserved or other provisions are made to offset the increased percentage of hfffdeever lot coverage that will be contained within the neck portion of the lots. (s) Private streets serving up to four lots may be permitted in residential developments with a density of less than four units per acre if the criteria in variance section 18-22 are met and upon consideration of the following: (1) The prevailing development pattern makes it unfeasible or inappropriate to construct a public street. In making this determination, the city may consider the location of existing property lines and homes, local or geographic conditions and the existence of wetlands. Planning Commission Pervious Paver Policy October 17, 2017 Page 15 of 35 (2) After reviewing the surrounding area, it is concluded that an extension of the public street system is not required to serve other parcels in the area, improve access, or to provide a street system consistent with the comprehensive plan. (3) The use of a private street will permit enhanced protection of the city's natural resources, including wetlands and protected areas. (t) Temporary cul-de-sac must be constructed at all locations where a street stub will be constructed and will be extended in the future. The temporary cul-de-sac must be 90 feet in diameter and lie within platted right-of-way or easement. The developer must submit an escrow for the cost of removing the temporary cul-de-sac and vacating the easement (if applicable). Sec. 20-109.-Applications. Application for a site plan review shall be made to the city planner on forms provided by the city and shall be filed 30 days in advance of the planning commission meeting, at which it is to be considered. Prior to filing an application for site plan review,the applicant shall attend a conference with city staff The primary purpose of the conference shall be to provide the applicant with an opportunity to gather information and obtain guidance on the general merits of the proposal and its conformity to the provisions of the comprehensive plan and the City Code before incurring substantial expense. Incomplete or deficient applications shall not be scheduled for a meeting unless the community development director has determined that official action is warranted. The application shall also include: (1) Evidence of ownership or an interest in the property; (2) The application fee; (3) Complete site plans, signed by a registered architect, civil engineer, landscape architect or other design professional,to include the following. (4) General: a. Name of project. b. Name, address and telephone number of applicant, engineer, and owner of record. c. Legal description(certificate of survey will be required). d. Date proposed, north arrow, engineering scale, number of sheets, name of drawer. e. Vicinity map showing relationship of the proposed development to surrounding streets,rights-of-way, easements and natural features. f. Description of intended use of the site, buildings and structures, including type of occupancy and estimated occupancy load. g. Existing zoning and land use. h. Tabulation box indicating: 1. Size of parcel in acres and square feet. 2. Gross floor area of each building. Planning Commission Pervious Paver Policy October 17, 2017 Page 16 of 35 3. Percent of site covered by building. 4. Percent of lot coverage on site covered broken out by impervious surface and pervious pavement. 5. Percent of site covered by parking area. 6. Projected number of employees. 7. Number of seats if intended use is a restaurant or place of assembly. 8. Number of parking spaces required. 9. Number of parking spaces provided including handicapped. 10. Height of all buildings and structures and number of stories. 11. Breakdown of the building area allocated for specific uses, e.g., manufacturing, office, retail, showroom, warehouse, etc. (5) Site and building plan: a. Property line dimensions, location of all existing and proposed structures with distance from boundaries, distance between structures, building dimensions and floor elevations. b. Grading and drainage plans showing existing natural features (topography, wetlands, vegetation, etc.), as well as proposed grade elevations and sedimentation and stormwater retention ponds. Plans shall include runoff and storage calculations for ten-year and 100-year events. If stormwater is proposed to be routed to existing stormwater ponds, documentation shall be provided to demonstrate that the downstream pond is sufficient to accommodate the additional stormwater. c. All existing and proposed points of egress/ingress showing widths at property lines, turning radii abutting rights-of-way with indicated centerline, width, paving width, existing and proposed median cuts, and intersections of streets and driveways. d. Vehicular circulation system showing location and dimension for all driveways, parking spaces, parking lot aisles, service roads, loading areas, fire lanes, emergency access (if necessary), public and private streets, alleys, sidewalks, bike paths, direction of traffic flow and traffic-control devices. e. Landscaping plan in accordance with the provisions of article XXV. f. Location, access and screening detail of trash enclosures. g. Location and screening detail of rooftop equipment. Screening shall be provided from the perspective of a point six feet high at all adjacent property lines or from a distance of 250 feet, whichever is greater. h. Location and detail of signage including method of lighting, height, width, sign display area, etc. i. Lighting location, style,mounting and photometrics. Planning Commission Pervious Paver Policy October 17, 2017 Page 17 of 35 j. Building elevations from all directions indicating materials and colors. Interior floor plans may be required. k. Utility plan identifying size and direction of existing water and sewer lines, fire hydrants, distance of hydrant to proposed building. 1. List of proposed hazardous materials,use and storage. m. Proposed fire protection system. n. Such other information as may be required by the city. o. Photocomposite images, artistic renderings, or site elevations which depict the visual impact of the proposed development's design, landscaping, street layout, signage, pedestrian ways, lighting, buildings, or other details that affect land use within the city shall be submitted. Such images and renderings shall be from key vantage points and provide an undistorted perspective of the proposed development from abutting properties, less intensive land uses, and/or from entryway locations. Photorealistic imaging or renderings are the appropriate level of resolution. (6) Within the HC districts, the application shall also include: a. Building elevations from all directions, indicating materials, colors and landscaping at installation. b. Building and site views from Highway 5, the appropriate access boulevard (north or south of Highway 5), and any other appropriate arterial or collector roadways. c. Site views showing the relationships of the proposed building or development to adjacent development, including buffered areas. d. Drawings of all significant or atypical site features, such as unusual landscaping, manmade water features other than retention ponds, outdoor sculpture, or other large-scale artwork and other uncommon constructs. e. Sample building materials. f. Sample paving materials, upon the city's request. (7) Within the BCO district, the application shall also include: a. Identified boundaries of the primary zone and secondary zone on a drawing depicting existing conditions and on a site plan depicting the proposed development pattern. b. Calculations and/or drawings that identify the allowable density(number of units or building coverage) under this Code, including lands lying in the primary and secondary zone. Calculation of allowable density shall specifically exclude lands classified as bluffs, floodplains and designated wetlands. Calculation of allowable impervious cover surface may include bluffs and floodplains but shall specifically exclude designated wetlands. Sec. 20-254. - Churches. (a) The following applies to churches located inside the Metropolitan Urban Services Area (MUSA): Planning Commission Pervious Paver Policy October 17, 2017 Page 18 of 35 (1) The site shall be located on a collector or arterial roadway as identified in the comprehensive plan or located so that access can be provided without conducting traffic through residential concentration. (2) The structure must be set back 50 feet from all property lines. (3) Parking areas shall be set back 25 feet from streets and nonresidential property. (4) ! -- -- - - - . . . - Lot coverage shall not exceed 70 percent of the site and the remainder is to be suitably landscaped in conformance with article XXV. (b) In addition to the criteria in subsection (a), the following applies to churches located outside the Metropolitan Urban Services Area: The following must be provided for review: a. Location of two drainfield sites. b. Two soil borings on each drainfield site for a total of four soil borings. c. No percolation tests for drainfield sites where the land slope is between zero and 12 percent. d. One percolation test per drainfield site where the land slope is between 13 and 25 percent. e. Areas where the land slope exceeds 25 percent shall not be considered as a potential soil treatment site. f. The sewage treatment system must be in conformance with chapter 19, article IV. g. School and day care uses accessory to the church use are not permitted unless approved by the city council. Sec. 20-485. - Stormwater management. Impervious surface Lot coverage of lots shall not exceed 25 percent of the lot area, except as follows: (1) Thirty-five percent for medium/high density residential zones; and (2) Seventy percent in industrial zones within the Lake Susan Shoreland District. Sec. 20-490. -Nonconforming lots. (a) A nonconforming single lot of record located within the Shoreland Management District may be allowed as a building site without variances from lot size requirements,provided that: (1) All structure and septic system setback distance requirements can be met; (2) A Type 1 sewage treatment system consistent with Minnesota Rules, Chapter 7080, can be installed or the lot is connected to a public sewer; and Planning Commission Pervious Paver Policy October 17, 2017 Page 19 of 35 (3) The impervious surface lot coverage does not exceed 25 percent. of the lot. (b) In a group of two or more contiguous lots of record under a common ownership an individual lot must be considered as a separate parcel of land for the purpose of sale or development, if it meets the following requirements: (1) The lot must be at least 75 percent of the dimensional standard for lot width and lot size for the shoreland classification; (2) The lot must be connected to a public sewer, if available, or must be suitable for the installation of a Type 1 sewage treatment system consistent with Minnesota Rules, Chapter 7080, and local government controls; (3) Impervious surface Lot coverage must not exceed 25 percent of each lot; and (4) Development of the lot must be consistent with the city's comprehensive plan. (c) A lot subject to subsection (b) not meeting the requirements of subsection (b) must be combined with the one or more contiguous lots so they equal one or more conforming lots as much as possible. (d)Notwithstanding subsection (b), contiguous nonconforming lots of record in the Shoreland Management District under a common ownership may be sold or purchased individually if each lot contained a habitable residential dwelling at the time the lots came under common ownership and the lots are suitable for, or served by, a sewage treatment system consistent with the requirements of M.S. § 115.55 and Minnesota Rules, Chapter 7080, or connected to a public sewer. (e) In evaluating all variances, zoning and building permit applications, or conditional use requests, the zoning authority shall require the property owner to address, when appropriate, stormwater runoff management, reducing impervious surfaces, increasing setback, restoration of wetlands,vegetative buffers, sewage treatment and water supply capabilities, and other conservation-designed actions. (f) A portion of a conforming lot may be separated from an existing parcel as long as the remainder of the existing parcel meets the lot size and sewage treatment requirements of the zoning district for a new lot and the newly created parcel is combined with an adjacent parcel. (Ord. No. 543, § 2, 6-25-12) Sec. 20-505. - Required general standards. (a) The city shall consider the proposed PUD from the point of view of all standards and purposes of the comprehensive land use plan to coordinate between the proposed development and the surrounding use. The city shall consider the location of buildings, I Planning Commission Pervious Paver Policy October 17,2017 Page 20 of 35 compatibility, parking areas and other features with response to the topography of the area and existing natural features, the efficiency, adequacy and safety of the proposed layout of streets; the adequacy and location of green areas; the adequacy, location and screening of noncompatible land uses and parking areas. (b) The applicant shall demonstrate that the PUD plan offers the city higher quality architectural and site design, landscaping, protection of wetlands, creeks and mature trees and buffering for adjoining properties that represent improvements over normal ordinance standards. (c) Density. An increase/transfer for density may be allowed at the sole discretion of the city utilizing the following factors: (1) Density within a PUD shall be calculated on net acreage located within the property lines of the site in accordance with the land use plan. (2) The area where the density is transferred must be within the project area and owned by the proponent. (3) Density transfer in single-family detached area will be evaluated using the items listed in sections 20-506 or 20-508. Density transfer eligible for multiple-family areas are not permitted to be applied to single-family areas. (4) In no case shall the overall density of the development exceed the net density ranges identified in the comprehensive plan except as specified in policies supporting the city's affordable housing goals. (d) The city may utilize incentives to encourage the construction of projects which are consistent with the city's housing goals. Incentives may include modification of density and other standards for developments providing low and moderate cost housing. Incentives may be approved by the city contingent upon the developer and the city entering into an agreement ensuring that the housing will be available to low and moderate income persons for a specific period of time. (e) Hard surface Lot coverage shall be limited as follows: Comprehensive Hard Surface Lot Plan Designation Coverage (%) Low or medium density residential 30 High density residential 50 Office 70 Commercial (neighborhood or community) 70 Commercial (regional) 70 Industrial 70 Mixed use 70* Individual lots within PUD may exceed these standards as long as the average meets these standards. 1 Planning Commission Pervious Paver Policy October 17, 2017 Page 21 of 35 (f) Building and parking setbacks from public streets shall be determined by the city based on characteristics of the specific PUD. Parking lots and driving lanes shall be set back at least 20 feet from all exterior lot lines of a PUD. Where industrial uses abut developed platted or planned single-family lots outside the PUD, greater exterior building and parking setbacks, between 50 and 100 feet, shall be required in order to provide effective screening. The city council shall make a determination regarding the adequacy of screening proposed by the applicant. Screening may include the use of natural topography or earth berming, existing and proposed plantings and other features such as roadways and wetlands which provide separation of uses. PUD's must be developed in compliance with buffer yard requirements established by the comprehensive plan and chapter 20, article XXV, of the Chanhassen City Code. (g) More than one building may be placed on one platted or recorded lot in a PUD. (h) At the time PUD approval is sought from the city, all property to be included within a PUD shall be under unified ownership or control or subject to such legal restrictions or covenants as may be necessary to ensure compliance with the approved master development plan and final site and building plan. After approval, parcels may be sold to other parties without restriction, however, all parcels will remain subject to the PUD development contract that will be recorded in each chain-of-title. (i) Signs shall be restricted to those which are permitted in the sign plan approved by the city and shall be regulated by permanent covenants or design standards established in the PUD development contract. (j) The requirements contained in articles XXIII and XXV of this chapter may be applied by the city as it deems appropriate. (k) The uniqueness of each PUD required that specifications and standards for streets,utilities, public facilities and subdivisions may be subject to modification from the city ordinances ordinarily governing them. The city council may therefore approve streets, utilities, public facilities and land subdivisions which are not in compliance with usual specifications or ordinance requirements if it finds that strict adherence to such standards or requirements is not required to meet the intent of this [article] or to protect the health, safety or welfare of the residents of the PUD,the surrounding area or the city as a whole. (1) No building or other permit shall be issued for any work on property included within a proposed or approved PUD, nor shall any work occur unless such work is in compliance with the proposed or approved PUD. (m) Buffer yards. (1) The city comprehensive plan establishes a requirement for buffer yards. Buffer yards are to be established in areas indicated on the plan where higher intensity uses interface with low density uses and shall comply with chapter 20, article XXV, of the Chanhassen City Code. (2) The buffer yard is not an additional setback requirement. The full obligation to provide the buffer yard shall be placed on the parcel containing the higher intensity use. Planning Commission Pervious Paver Policy October 17, 2017 Page 22 of 35 (3) The buffer yard is intended to provide physical separation and screening for the higher intensity use. As such, they will be required to be provided with a combination of berming, landscaping and/or tree preservation to maximize the buffering potential. To the extent deemed feasible by the city, new plantings shall be designed to require the minimum of maintenance, however, such maintenance as may be required to maintain consistency with the approved plan, shall be the obligation of the property owner. Sec. 20-575. - Lot requirements and setbacks. The following minimum requirements shall be observed in an "A-2" District subject to additional requirements, exceptions, and modifications set forth in this chapter: (1) The minimum lot area is two and one-half acres, subject to section 20-906. A one-unit per ten-acre gross density shall be maintained for proposed lots outside the approved Metropolitan Urban Services Area in effect at the time of a proposed development. This requirement shall not apply to lots of record in existence on January 15, 1987 or lots created thereafter if they were subject to a pending subdivision application on that date and the lots were created as a result of that application. The one-unit per ten-acre density applies to contiguous property under single ownership. Acreage under single ownership, which is not contiguous, cannot be combined for increased density/building eligibility on one of the parcels. Once a building eligibility has been used for a property, a development contract must be recorded with the county establishing the number of building eligibilities remaining or documenting that no building eligibility remains. (2) The minimum lot frontage is 200 feet, except that the minimum lot frontage of lots fronting on a cul-de-sac shall be at least 200 feet at the building setback line. (3) The minimum lot depth is 200 feet, except that lots fronting on a cul-de-sac shall be at least 200 feet at the building setback line. (4) The maximum lot coverage is 20 25 percent, of which no more than 20 percent can be impervious surfaces. (5) The minimum setbacks are as follows: a. For front yards, 50 feet. b. For rear yards, 50 feet. c. For side yards, ten feet. (6) The maximum height is as follows: a. For the principal structure, three stories/35 feet. b. For accessory structures, three stories/35 feet. (7) The minimum driveway separation is as follows: a. If the driveway is on a collector street, 400 feet. b. If the driveway is on an arterial street, 1,250 feet. Planning Commission Pervious Paver Policy October 17,2017 Page 23 of 35 (Ord. No. 80, Art. V, § 3(5-3-5), 12-15-86; Ord. No. 170, § 1, 7-23-92; Ord. No. 194, § 1, 10-11- 93; Ord. No. 332, § 1, 12-10-01; Ord. No. 377, § 75, 5-24-04) Sec. 20-595.- Lot requirements and setbacks. The following minimum requirements shall be observed in an "RR" District subject to additional requirements set forth in this chapter: (1) The minimum lot area is two and one-half acres, subject to section 20-906. A one-unit per ten-acre gross density shall be maintained for proposed lots outside the approved Metropolitan Urban Services Area in effect at the time of a proposed development. This requirement shall not apply to lots of record in existence on January 15, 1987 or lots created thereafter if they were subject to a pending subdivision application on that date and the lots were created as a result of that application. The one-unit per ten-acre density applies to contiguous property under single ownership. Acreage under single ownership, which is not contiguous, cannot be combined for increased density/building eligibility on one of the parcels. Once a building eligibility has been used for a property, a development contract must be recorded with the county establishing the number of building eligibilities remaining or documenting that no building eligibility remains. (2) The minimum lot frontage is 200 feet, except that the minimum lot frontage of lots fronting on a cul-de-sac shall be at least 200 feet at the building setback line. (3) The minimum lot depth is 200 feet, except that lots fronting on a cul-de-sac shall be at least 200 feet at the building setback line. (4) The maximum lot coverage is 20 25 percent, of which no more than 20 percent can be impervious surfaces. (5) The minimum setbacks are as follows: a. For front yards, 50 feet. b. For rear yards, 50 feet. c. For side yards, ten feet. (6) The maximum height is as follows: a. For the principal structure, three stories/35 feet. b. For accessory structures, three stories/35 feet. (7) The minimum driveway separation is as follows: a. If the driveway is on a collector street, 400 feet. b. If the driveway is on an arterial street, 1,250 feet. (Ord. No. 80, Art. V, § 4(5-4-5), 12-15-86; Ord. No. 127, § 2, 3-26-90; Ord. No. 170, § 2, 6-8- 92; Ord. No. 194, § 2, 10-11-93; Ord. No. 332, § 2, 12-10-01; Ord. No. 377, § 79, 5-24-04) Sec. 20-615. - Lot requirements and setbacks. The following minimum requirements shall be observed in an "RSF" District subject to additional requirements, exceptions and modifications set forth in this chapter and chapter 18: Planning Commission Pervious Paver Policy October 17, 2017 Page 24 of 35 (1) The minimum lot area is 15,000 square feet. For neck or flag lots, the lot area requirements shall be met after the area contained within the "neck" has been excluded from consideration. (2) The minimum lot frontage is 90 feet, except that lots fronting on a cul-de-sac "bubble" shall be 90 feet in width at the building setback line. The location of this lot is conceptually illustrated below. Lotwhere h measured'st the setback.lie. Atii, iiriv iitp ism. 1 sir--- miw , - swo:if 1 1 P 4 *r Frontage Measured at Setback Line (3) The minimum lot depth is 125 feet. (4) Lot width on neck or flag lots and lots accessed by private streets shall be 100 feet as measured at the front building setback line. The location of these lots is conceptually illustrated below. Planning Commission Pervious Paver Policy October 17, 2017 Page 25 of 35 NECK/FLAG LOTS FRONT LOT LINE STREET + ! f 4 j t t 100'LOT WIDTH a lin 414 + I LOT i l ff WIDTH ' t LMU, mist amil Neck/Flag Lots (5) The maximum lot coverage for all structures and paved surfaces is 25 30 percent, of which no more than 25 percent can be impervious surfaces. For flag/neck lots neither the area within the neck, nor the impervious surface lot coverage of the driveway within the neck shall be included within the calculation of the lot area or lot coverage of the lot. (6) The setbacks are as follows: a. For front yards, 30 feet. b. For rear yards, 30 feet. c. For side yards, ten feet. (7) The setbacks for lots served by private streets and/or neck lots are as follows: a. For front yard, 30 feet. The front yard shall be the lot line nearest the public right- of-way that provides access to the parcel. The rear yard lot line is to be located opposite from the front lot line with the remaining exposures treated as side lot lines. On neck lots the front yard setback shall be measured at the point nearest the front lot line where the lot achieves a 100-foot minimum width. b. For rear yards, 30 feet. c. For side yards, ten feet. (8) The maximum height is as follows: a. For the principal structure, three stories/35 feet. b. For accessory structures, 20 feet. (Ord. No. 80, Art. V, § 5(5-5-5), 12-15-86; Ord. No. 90, § 1, 3-14-88; Ord. No. 127, § 3, 3-26- 90; Ord. No. 145, § 2, 4-8-91; Ord. No. 240, § 18, 7-24-95; Ord. No. 324, § 23, 7-9-01; Ord. No. 377, § 81, 5-24-04; Ord. No. 409, § 4, 1-9-06; Ord. No. 619, § 7, 2-27-17) Planning Commission Pervious Paver Policy October 17,2017 Page 26 of 35 Editor's note— Section 2 of Ord. No. 145 purported to amend § 20-615(6)b. pertaining to accessory structures; such provision were contained in § 20-615(7)b., subsequent to amendment of the section by Ord. No. 127. Hence, the provisions of Ord. No. 145, § 2, were included as amending § 20-615(7)b. Sec. 20-635. -Lot requirements and setbacks. The following minimum requirements shall be observed in an "R-4" district subject to additional requirements, exceptions and modifications set forth in this chapter: (1) The minimum lot area is as follows: a. For a detached single-family dwelling unit, 15,000 square feet per unit. b. For a two-family dwelling, 10,000 square feet per dwelling unit. (2) The minimum lot frontage is as follows: a. For a single-family dwelling, 80 feet. b. For a two-family dwelling, 50 feet per dwelling unit. c. If the lot fronts on a cul-de-sac the width of the lot at the building setback lines shall be: 1. In the case of a single-family dwelling, 80 feet. 2. In the case of a two-family dwelling, 50 feet. (3) The minimum lot depth is 125 feet. (4) The maximum lot coverage for all structures and paved surfaces is 30 35 percent, of which no more than 30 percent can be impervious surfaces. (5) The setbacks are as follows: a. For front yards, 30 feet. b. For rear yards, 30 feet. c. For side yards,ten feet. (6) The maximum height is as follows: a. For the principal structure,three stories/35 feet. b. For accessory structures, one story/15 feet. (Ord. No. 80, Art. V, § 6(5-6-5), 12-15-86; Ord. No. 90, § 2, 3-14-88; Ord. No. 377, § 83, 5-24- 04) Sec. 20-641. - Intent. The intent of the "RLM" district is to provide for single-family attached or detached residential development on land guided residential—low or medium density in the city's comprehensive plan with a maximum net density of eight units per acre. The "RLM" district is intended to be used where large areas of upland will be preserved or created as permanent open space to balance the higher hard surface lot coverage permitted on individual lots. 1Planning Commission Pervious Paver Policy October 17, 2017 Page 27 of 35 Sec. 20-645. -Lot requirements and setbacks. The following minimum requirements shall be observed in an "RLM" district subject to additional requirements, exceptions and modifications set forth in this chapter: (1) The minimum lot area is as follows: a. If a single-family dwelling is located on the lot, 9,000 square feet per dwelling unit. b. If a two-family dwelling is located on the lot, 7,260 square feet per dwelling unit. c. If a townhouse or multiple-family project is located on the lot, an average of 5,445 square feet per dwelling unit. (2) The minimum lot frontage: a. Single-family and two-family dwellings are 50 feet except that in the case of a lot that fronts on a cul-de-sac or on the outside of a curve on a curvilinear street, the width of the lot at the building setback line shall be 50 feet. b. Townhouses and multifamily dwellings are 30 feet except that in the case of a lot that fronts on a cul-de-sac or on the outside of a curve on a curvilinear street, the width of the lot at the building setback line shall be 30 feet. (3) The minimum lot depth: a. If a single-family dwelling, the minimum depth is 110 feet. b. If a two-family dwelling minimum depth is 100 feet. c. If a townhouse or multiple-family dwelling minimum depth is 100 feet. (4) The maximum lot coverage is: a. If a single-family dwelling, 35 40 percent, of which no more than 35 percent can be impervious surfaces. b. If a two-family dwelling, 40 45 percent of which no more than 40 percent can be impervious surfaces. . c. If a townhouse or multiple-family dwelling 50 percent. (5) The setbacks are as follows: a. If a single-family dwelling: 1. For front yards, 25 feet. 2. For rear yards, 25 feet. 3. For side yards, five feet on garage side and ten feet on house side. Minimum separation between structures on adjacent parcels shall be 15 feet. b. If a two-family dwelling: 1. For front yards, 25 feet. 2. For rear yards, 30 feet. Planning Commission Pervious Paver Policy October 17, 2017 Page 28 of 35 3. For side yards, ten feet where no common wall is located. c. If a townhouse or multiple-family dwelling: 1. For front yards, 25 feet. 2. For rear yards, 25 feet. 3. For side yards, ten feet where no common wall is located. (6) The maximum height is as follows: a. For the principal structure, three stories/35 feet. b. For accessory structures, one story/15 feet. (Ord. No. 377, § 85, 5-24-04; Ord. No. 423, § 4, 6-12-06) Sec. 20-905. - Single-family dwellings. All single-family detached homes shall: (1) Be constructed upon a continuous perimeter foundation that meets the requirements of the state building code. (2) Conform to the following standards for living areas: a. If a one-story rambler design,have an area of 960 square feet. b. If a split level design,have an area of 1,050 square feet. c. If a split foyer and two-story design, have an area of 600 square feet on the first floor. d. A two-car garage must be provided with the single-family structure. (3) Have an earth covered, composition, shingled or tiled roof or other materials approved by the Minnesota State Building Code as adopted and amended by the city. (4) Receive a building permit. The application for a building permit in addition to other information required shall indicate the height, size, design and the appearance of all elevations of the proposed building and a description of the construction materials proposed to be used. (5) Meet the requirements of the Minnesota State Building Code, as adopted and amended by the city or the applicable manufactured housing code. (6) Where access doors are proposed from a dwelling to the outdoors, which does not connect directly to a sidewalk or stoop, a minimum ten feet by ten feet hard surface area of patio shall be assumed. Such hard surface This patio area must be shown to comply with required property line, lake and wetland setbacks; may not encroach into conservation or drainage and utility easements; and shall not bring the site's l surface lot coverage above that permitted by ordinance. Sec. 20-921 —Pervious Pavement Properly designed, installed, and maintained pervious pavements have the capacity to allow for stormwater detention and/or infiltration. When not properly designed, installed, Planning Commission Pervious Paver Policy October 17, 2017 Page 29 of 35 and maintained pervious pavements fail to facilitate the detention and/or infiltration of stormwater. Additionally, pervious pavements contribute to the creation of heat islands and do not provide the same surface water managements benefits as native vegetative cover. For these reasons, it is necessary to regulate the lot coverage, design, installation, and maintenance of these systems. 1) Lot Coverage: Pervious pavements are considered to constitute lot coverage; however, they do not constitute impervious surfaces. 2) Location Restrictions: a. Pervious Pavements may not be installed in areas where trash or garbage receptacles will be stored. 3) Installation: a. To meet the city's definition of pervious pavement the system must be designed in compliance with standards established by the Interlocking Concrete Pavement Institute (ICPI) and installed by an ICPI certified installer. b. The City Engineer may permit pervious pavement technologies other than permeable interlocking concrete pavers, so long as the City Engineer determines they are functionally equivalent or better, and the system is designed in compliance with accepted guidelines and is installed by an appropriately certified installer. 4) Maintenance: a. The owner of a pervious paver system must enter into a maintenance agreement with the city to ensure the system performs as designed in perpetuity. This agreement must conform to the manufactures guidelines, and stipulate the frequency and type of maintenance to be performed. Sec. 20-1072. - Landscaping. (a) Where natural or existing topographic patterns contribute to the beauty or utility of a development, they shall be preserved to the greatest extent possible. Modification to topography will be permitted where and to the extent that it contributes to good design. All topographic modifications shall adhere to the practices delineated in the city's surface water management plan. (b) The grades of all walks,parking spaces, terraces, and other paved areas shall conform with the requirements of the Americans with Disabilities Act. In addition, they shall provide an inviting and stable appearance for walking. Stairs and ramps may be substituted for slanted pavement when necessary. (c) All landscape shall preserve and enhance natural features (such as wetlands, drainage ways, mature stands of trees, and the like), enhance architectural features, strengthen vistas and important axes, and provide shade. (d) Landscaping shall emphasize massing of plant materials over isolated or scattered placement of individual specimens. Reforestation as prescribed by the city's tree preservation and reforestation ordinance is encouraged. Planning Commission Pervious Paver Policy October 17, 2017 Page 30 of 35 wr ,..4 art ogrAV 4111* At_ 410 +a. DO THIS NOT THIS Massing of Plant Materials (e) Unity of design shall be achieved by repetition of certain plant varieties and other materials, and by correlation with natural existing materials and adjacent developments where appropriate. RBE1RION OF MATERIALS— 1 1111 p =I 111111 Unity of Design (f) Plant material shall be selected for interest in its structure, texture and color, and for its ultimate growth size. Plants that are indigenous to the area and others that will be hardy, harmonious to the design of good appearance, and of relatively easy maintenance shall be used. (g) In locations where plants will be susceptible to injury by pedestrian or motor traffic, they shall be protected by appropriate curbs, tree guards, or similar devices. TRH GUARD TRffirtOTECROW Tree Diagram Planning Commission Pervious Paver Policy October 17, 2017 Page 31 of 35 (h) Where building sites limit planting, the placement of trees in parkways, gardens, or paved areas is encouraged. Trees should be clustered whenever possible, and consideration shall be given to the special needs of plants surrounded by impervious surfaces. In these instances, preference is given to surrounding plantings with pervious pavers to allow for the infiltration of stormwater into the root zone. 0-751 cR2I LC? QJ I I DO THS NOT THS TREE PLACEMENT Tree Placement (i) In areas where general planting will not prosper, other solutions—such as fences, walls, rock gardens, raised planters, or paving of wood, brick stone, gravel, or cobbles—shall be used. Carefully selected plants shall be included. LOAM*ZONE BALING SCREEN/FENCE OR WAL „i--_ BULDtJG PARKING II -�• OAROEN ORNAMENTAL TREE II CONCRETE WALK ', 11K,‘:•-T,‘ `•:^_ GRASS Q STREET TREE STREET ALTERNATIVE LANDSCAPE TREATMENT Rock Gardens (j) Landscaping and tree removal shall be consistent with article XXV in the City Code. Sec. 20-1122. - Access and driveways. The purpose of this section is to provide minimum design criteria, setback and slope standards for vehicular use. The intent is to reduce interference with drainage and utility easements by providing setback standards; reduce erosion by requiring a hard surface for all driveways; to limit the number of driveway access points to public streets and to direct drainage toward the street via establishment of minimum driveway slope standards. Parking and loading spaces shall have proper access from a public right-of-way. The number and width of access drives shall be located to minimize traffic congestion and abnormal traffic hazard. All driveways shall meet the following criteria: (1) Driveways shall be setback at least ten feet from the side property lines, except on lots that access off of a cul-de-sac "bubble", neck or flag lot where the lot frontage may Planning Commission Pervious Paver Policy October 17, 2017 Page 32 of 35 prohibit meeting the side yard setback requirement. Beginning 20 feet from the front property line, driveways may be setback a minimum of five feet from the side property line or the distance of the existing drainage and utility easement on the particular lot or parcel. Encroachment into a side yard drainage and utility easement must be reviewed and approved by the city and may require an encroachment agreement. (2) Driveway grades shall be a minimum of one-half of one percent and a maximum grade of ten percent at any point in the driveway. If extenuating circumstances exist, the city engineer may approve driveway grades in excess of ten percent. Examples of extenuating circumstances include: bluffs, existing steep grades, shoreland setbacks, wetland conditions, and tree preservation. (3) Within the right-of-way driveways should access city streets at 90 degrees. (4) In areas located within the Metropolitan Urban Services Area (MUSA) as identified on the comprehensive plan, driveways shall be surfaced with bituminous, concrete or other hard surface material, as approved by the city engineer. In areas outside the MUSA, driveways shall be surfaced from the intersection of the road through the right- of-way portion of the driveway with bituminous, concrete or other hard surface material, as approved by the city engineer. (5) On corner lots, the minimum corner clearance from the roadway right-of-way line shall be at least 30 feet to the edge of the driveway. (6) For A-2, PUD-R for single-family detached houses, RR, RSF, R-4 and RLM for single-family detached residential uses, the width of the driveway access shall not exceed 24 feet at the right-of-way line. No portion of the right-of-way may be paved except that portion used for the driveway. Inside the property line of the site, the maximum driveway width shall not exceed 50 feet. For flag/neck lots the impervious spec lot coverage of the driveway access within the neck portion of flag/neck lots shall not exceed 33 percent of the neck's area. For all lots the minimum driveway width shall not be less than ten feet. (7) For all other uses, the width of the driveway access shall not exceed 36 feet in width measured at the roadway right-of-way line. No portion of the right-of-way may be paved except that portion used for the driveway. (8) Driveway setbacks may be reduced subject to approval by the city engineer and the following criteria: a. The driveway will not interfere with any existing drainage swale or easement in which a utility is contained; b. Shall require an easement encroachment agreement from the engineering department; c. The driveway must be designed to maintain stormwater drainage runoff on the property to ensure that it will not cause runoff onto adjacent properties; d. Snow storage may not be placed on adjacent properties; and e. Lot frontage on lots that access off of a cul-de-sac "bubble", neck or flag lot do not permit adequate driveway access width or side yard setback. Planning Commission Pervious Paver Policy October 17, 2017 Page 33 of 35 (9) Accessory driveways shall be maintained as natural grass or be constructed of bituminous, concrete, or paver surface. (10) One driveway access is allowed from a single residential lot to the street. (11) A turnaround is required on a driveway entering onto a state highway, county road or collector roadway as designated in the comprehensive plan, and onto city streets where this is deemed necessary by the city engineer, based on traffic counts, sight distances, street grades, or other relevant factors. If the engineer requires a turnaround, this requirement will be stated on the building permit. (12) Separate driveways serving utility facilities are permitted. (13) All driveways must be constructed in accordance with current construction requirements/details. A driveway permit is required when any alteration is made to a driveway in the public right-of-way. A zoning permit may be required for any other driveway work not in the public right-of-way along with other requirements to determine if the improvement will meet zoning ordinance requirements of the particular lot or parcel. Sec. 20-1181. -Vehicular areas. (a) When parking lot perimeters where vehicular areas, including driveways and drive aisles, are not entirely screened visually by an intervening building or structure or land mass from any abutting right-of-way, there shall be provided landscaping designed to buffer direct views of cars and vehicular use areas hard surface arcs. The landscaping must break up expanses of hard surface vehicular use areas, help to visually define boulevards and soften direct views of parking areas and provide for reforestation with overstory tree from the approved tree species list identified for parking or other species as approved by city staff. All new planting areas must have an irrigation system installed. Publicly owned and operated parking lots used for long duration parking may be exempt from this requirement when there is a demonstrated concern regarding security safety. 0 • 110 1 1 1 4 • S: Illustration (b) Interior landscaping for vehicular use areas: (1) Any open vehicular use areas containing more than 6,000 square feet of area, or 20 or more vehicular parking spaces, shall provide interior landscaping in accordance with this division in addition to "perimeter" landscaping. Interior landscaping may be Planning Commission Pervious Paver Policy October 17,2017 Page 34 of 35 peninsular or island types. Landscaped area shall include all parking lot and drive islands and perimeter green spaces. Required setback areas shall be excluded. (2) For each 100 square feet, or fraction thereof, of vehicular use area, eight square feet of landscaped area shall be provided. (3) The minimum landscape area permitted shall be 200 square feet, with a six-foot minimum dimension to all trees from edge of pavement where vehicles overhang and a four-foot minimum dimension to all trees where vehicles do not overhang. (4) In order to encourage the required landscape area to be properly dispersed, a minimum of one peninsular, island, or boulevard type landscaped area shall be located within each 6,000 square feet of vehicular use area. (5) A minimum of one tree shall be required for each 250 square feet or fraction thereof, of required landscape area. Trees shall have a clear trunk of at least five feet above the ground, and the remaining area shall be landscaped with shrubs, or ground cover (not to include rocks or gravel except as a mulch around shrubs and ground cover), not to exceed two feet in height. (6) The inside width, behind the curb in landscape islands or peninsulas, shall be a minimum of ten feet. (7) All landscaped areas shall be protected by concrete curbing. (8) All landscaping area shall have the proper soil preparation to ensure the viability of the vegetation to survive. The landscaping plan shall provide specifications for proper soil preparation. Sec. 20-1408. - . Lot coverage Creation of impervious surfaces Lot coverage, impervious surfaces and pervious pavement, within the bluff setback may contribute to bluff instability due to increased runoff and/or erosion. Impervious surfaces are Lot coverage is prohibited within the bluff setback unless specifically authorized within this article. Sec. 20-1556. - Impervious surface, lot coverage, and slopes. To the greatest extent possible, all development shall minimize the amount of impervious surface by clustering development,using common access drives and utility corridors and minimizing building footprint size. Roads, walkways,bike trails, and parking areas must be designed parallel to natural contours with consideration to maintaining consolidated areas of natural topography and vegetation. Management of surface runoff caused by impervious cover shall be designed using practices delineated in the city's surface water management plan. Within the secondary zone of the BCO district, areas with average slopes exceeding 25 percent shall be preserved in their natural state and maintained as permanent open space. Areas with average slopes less than 25 percent but greater than ten percent shall not exceed 25 percent lot coverage.an impervious surface coverage of 25 percent. Impervious coverage Lot coverage for areas where average slopes are less than ten percent shall be governed by the underlying zoning district. I Planning Commission Pervious Paver Policy October 17, 2017 Page 35 of 35 Attachments: 1) Research Table 2) Pavers Ordinance G:\PLAN\City Code\2017\Various\Pavers\Staff Memo Planning Commission Pervious Pavers 10_11_2017 Impervious Surface Rules and Policies of Select Cities. City Terms Definitions Residential Approach Non-residential Approach Shoreland Pavers/Pervious Tech Notes Chanhassen Hardcover/Impervious see impervious surface/anything that substantially Limit on%lot coverage and paved Limit on%lot coverage and paved 25%except 35%for medium/high res Policy is to classify as impervious Surface/Lot Coverage reduces or prevents infiltration of surfaces. Detached single family surfaces. and 70%in Lake Susan Industrial Zones. surface. stormwater/portion of lot covered by impervious generally 20-35%. surface Chaska Floor Area Ratio/Lot Coverage Total floor area divided by total lot area/lot area Some zones have FAR(.25 for primary,.4 Limits on FAR and Building Coverage. 30%limit on impervious. Pavers do not count. Emailed.Summary of response:Pavers covered by principal and accessory buildings w/accessory),most seem limited by don't count.Only count buildings and setbacks and restrictions on size and accessory structures.No exceptions. number of accessory structures. Cottage Grove Floor Area Ratio/impervious Floor area divided by lot area/undefined Limit on number and size of accessory by Maximum Building Coverage. Maximum Building Coverage Unclear. Do not define impervious,best guess is district,limit on impervious%in rear they ignore non-buildings.Emailed.No yard,and%limit on impervious surface response. or structures...10 to 50%. Elk River Floor Area Ratio/Lot Coverage Floor area divided by lot area/%of lot area that Limit on lot coverage.Detached single Limit on%lot coverage. 25%impervious surface.No credit Counts as impervious in shoreland. Emailed.Summary of response:Only can be covered by principle and accessory family generally 25%,40%for multi- allowed.All count. buildings count outside of shoreland.In structures. family.Rural accessory caped by number shoreland everything counts.Handle and size,others seem limited by exceptions through variance process. setbacks.Only structures count Inver Grove Heights Impervious Surface area covered or physically altered and has hard Limited number of accessory structures Limit on impervious surface or 25%(high if they provided implemented Considered impervious *I like this*Emailed.Summary of surface which increases flow rate(everything but with maximum size,sliding impervious% building coverage. storm water management plan and CUP) Response:All count,but get bonus 10% decks). with lots less than 9,000 being allowed for engineered systems. 40%and larger lots being allowed 10%, can get extra 10%via CUP. Lino Lakes Impervious Surface Compacted surface or surface covered by Limit%lot cover for accessory building Lot coverage% 30%1-2 family res,35%for 3-4 family Not impervious(if engineered). Emailed.Summary of Response:Must materials that increase run off(list everything) and garage,maximum size,and number. res,60%for Com/Ind.Minimum open provide engineered diagrams,and up to Detached single family limited to 40% space for developments. 100%credit for impervious if engineer impervious. agrees. Prior Lake Floor Area Ratio/impervious floor area divided by lot area/covering that does rear lot maximum of 30%cover and size Floor area ratio for some districts. 30% Considered impervious. Emailed.Summary of response:Pervious not allow water to percolate in natural soil. limit,ground floor area ratio cap for not credited.Sidewalks under 3'wide and some districts(.30-.35). open decks don't count.Rest does. Rosemount Impervious Surface/Lot Coverage surface that allows little to no water Limit on size of accessory structures, Maximum lot coverage District standards. Ordinance Silent,but city has been Emailed.Summary of response:All but penetration/%of lot covered with structures, maximum lot coverage(30-40%detached allowing credit if engineered(case decks are lot coverage. Pavers are paved and other impervious surfaces. single family), by case). evaluated case by case.Ordinance is silent,but if applicants provided detailed engineering the City has been allowing pavers. Savage Floor area ratio/Impervious floor area divided by lot area/area that cannot limit on size and number of accessory Maximum Building Coverage. 30% Considered impervious.No credit Emailed.Summary of response:Pavers Surface absorb rainfall and cause increased run off structures,35%impervious surface(can given. are impervious,patios,pools,driveways, be increased through CUP),no structure sport courts,sheds,all roof count, over 5%of rear yard. residential caped at 35%but can exceed with CUP through engineering. Shakopee Floor area ratio/impervious floor area divided by lot area/%of lot area 30 to 50%impervious surface Maximum impervious surface 25% Considered impervious. Emailed.Summary of response: surface percentage covered by surfaces impervious to penetration by coverage Everything including decks and pools are water. considered impervious.PUD/variance allowed to exceed. City Terms Definitions Residential Approach Non-residential Approach Shoreland Pavers/Pervious Tech Notes Stillwater Floor area ratio floor area divided by lot area Some stipulated maximum lot coverage, Maximum lot coverage. 25% Pavers count,sometimes if houses Emailed.Summary of Response:Patios, limits on maximum accessory structure get variance to exceed they require decks,driveways,houses,sheds,and size and number. they use pavers. garages are lot coverage.Abby called: Everything is considered impervious, older districts are 25%structure and 25% non,seventies to eighties subdivisions limited to 30%,newer are unlimited so long as setbacks meet.They try to look at the total subdivision's stormwater. Minnetonka Floor area ratio/impervious floor area divided by lot area/material providing a floor area ratio limit,limit on structure Floor area ratio and impervious 30%impervious within 150'of OHWL, Credit for void space and up to 30% Emailed.Summary of Responses:Drew: surface/lot coverage hard surface that prevents normal infiltration of size,setbacks surface limit 75%impervious outside 150'of OHWL if engineered. City doesn't have max requirements stormwater/portion of lot covered by impervious, outside of shoreland.Setbacks are only building,driveway,or parking. limit.Within shoreland there are limits and options for reducing coverage; Aaron:short is credit for void spacing, sometimes credit on design(up to 30%)if engineered.Count everything in Shoreland,rest currently exempt. Eden Prairie Base area ratio/floor area ratio 1st floor area divided by lot area/floor area accessory building floor area ratio limited Floor or base area ratios,some have 30% Unclear,but given that they focus Emailed.No response. divided by lot area impervious caps on building floor area it is unlikely they count them as impervious. Victoria Floor area ratio/impervious floor area divided by lot area/prevents or reduces maximum lot coverage(25%for single maximum lot area and/or floor area Definition states pavers don't Emailed.Summary of response: surface/lot coverage infiltration(pavers don't count)/area of lot family detached),maximum size of ratio count. Homeowners can replace existing HC with occupied by buildings accessory structures, pavers to reduce percentage,all but retaining walls treated as HC.For Pervious Drives must use contractor and submit engineered diagram. Shorewood Impervious Surface an artificial or natural surface through which limit number and size of accessory Maximum impervious surface 25% Only give credit for pavers if Emailed.Summary of Response:Brad water,air or roots cannot pass. buildings,33%impervious for single coverage property is way over and willing to Nielsen(bnielsen@ci.shorewood.mn.us) family detached. significantly reduce. would like a copy of report.Everything counts as lot cover/impervious. Interested in pavers but concerned with maintenance and enforcement. Waconia Floor area ratio/hardcover floor area divided by lot area/any structure or 35%hardcover for detached residential, Maximum hardcover surface 25% Considered impervious. Emailed.Summary of Response:Pervious surface material that reduces or prevents the infiltration maximum floor area are considered impervious. However if of storm water including structures,driveways they can infiltrate some credit can be with any type of pavement or gravel. given through the variance process.Very case by case.Pretty much everything but decks and fences are counted as impervious.PUDS can have higher caps. St.Louis Park Floor area ratio/impervious floor area divided by lot area/surface compacted building size limits and no more than 25% Maximum floor area ratio No zone? Not impervious(if engineered). Emailed.Summary of Response:Zoning surface or covered,includes most conventionally surfaced of rear yard,ground floor ratio for doesn't'have limited(FAR only), structures. principle.35 for detached single family, Engineering doesn't count pervious pavers as impervious,as long as stormwater is managed engineering allows lot coverage,Sites must meet watershed requirements. City Terms Definitions Residential Approach Non-residential Approach Shoreland Pavers/Pervious Tech Notes Edina Floor area ratio floor area divided by lot area building size limits,building and structure Maximum floor area ratio and lot No zone? free 150 pavers and decking for Emailed.From Phone Call:Parking lots coverage limits both percent and cap sq. coverage patio then count.Piecemeal.Most and driveways are excluded,as are sport ft.for detached single family(25-30%) stuff doesn't count. courts,sidewalks,pools and a 4'apron, Grading/drainage management and most other things.Engineering:no through engineering(don't do it code stops 100%Ic,want to use through zoning cause it would engineering for lots over 50%,says linden create too many non-conforming). hills has 65%cap.require full lot survey (like our grading plan),no net increase... 10 yr atlas 14 for problem areas(non- issue not required),lots of discretion, concerns about maintenance especially when dealing with roof runoff.Note: Email Charlie(cgerk@EdinaMN.gov) report once drafted! Carver limit on number and size of accessory Limit maximum impervious and No zone? NA Emailed.Summary of Response:No structures,cannot have accessory maximum structure coverage regulation of lot coverage. footprint greater than 75%principal CITY OF CHANHASSEN CARVER AND HENNEPIN COUNTIES, MINNESOTA ORDINANCE NO. [insert number] AN ORDINANCE AMENDING CHAPTER 1, GENERAL PROVISIONS, CHAPTER 7, BUILDING AND BUILDING REGULATIONS, CHAPTER 18, SUBDIVISIONS,AND CHAPTER 20, ZONING OF THE CHANHASSEN CITY CODE THE CITY COUNCIL OF THE CITY OF CHANHASSEN,MINNESOTA ORDAINS: Section 1. Section 1-2 of the Chanhassen City Code is amended to read as follows: Hardcover. See Impervious surface . Impervious surface means a surface that either prevents or retards the entry of water into the soil and causes water to run off the surface in greater quantities and at an increased rate of flow than prior to development. Examples include,but are not limited to,rooftops, storage areas, roads, sidewalks,patios, driveways, or parking lots made of concrete, asphalt,rock, or non-pervious pavement systems. (20) Lot coverage means that portion or percentage of a lot that is covered by impervious surfaces and pervious pavement. (20) Pervious pavement allows storm water runoff to filter though surface voids into an underlying stone reservoir where it is temporarily stored and/or infiltrated. Examples of this technology include,but are not limited to porous pavers and permeable interlocking concrete pavers (PICP). Structure means anything manufactured, built, constructed, erected, or a portion thereof which is normally attached to or positioned on land, whether temporary or permanent in character, including, but not limited to, buildings, fences, sheds, advertising signs, dog kennels, hard surface parking areas, boardwalks, playground equipment, patios, or concrete slabs. (7) 20) Section 2. Section 7-19(12) of the Chanhassen City Code is amended to read as follows: (12) Indication of direction of surface water drainage by arrows; Section 3. The Chanhassen City Code is amended by adding Section 7-19(21) to read as follows: (21) Calculation of the amount and percentage of the lot coverage broken out by impervious surfaces and pervious pavement, if present. Section 4. Section 18-57(p)(7) of the Chanhassen City Code is amended to read as follows: 1 (7) The private street serving residential development with a density of less than four units per acre, must be located within a strip of property at least 30 feet wide extending out to the public right-of-way or covered by a 30-foot wide easement that is permanently recorded over all benefited and impacted parcels. Neither the area within the easement for the private street,nor the lot coverage of the private street shall be included within the calculation of the lot area or lot coverage of the lot in which the easement is located. Once the private street terminates, the area of the easement and lot coverage of the driveway shall be included in the calculation of lot area and lot coverage for the lot. Section 5. Section 18-57(p)(8) of the Chanhassen City Code is amended to read as follows: (8) Private streets serving residential development with a density equal to or greater than four units per acre, commercial, office, office industrial, or mixed-use districts, must be located within a strip of property at least 40 feet wide extending out to the public right- of-way or covered by a 40-foot wide easement that is permanently recorded over all benefited and impacted parcels.Neither the area within the easement for the private street, nor lot coverage of the private street shall be included within the calculation of the lot area or lot coverage of the lot in which the easement is located. Once the private street terminates, the area of the easement and lot coverage of the driveway shall be included in the calculation of lot area and lot coverage for the lot. Section 6. Section 18-57(r)(4) of the Chanhassen City Code is amended to read as follows: (4) Sufficient open space is preserved or other provisions are made to offset the increased percentage of lot coverage that will be contained within the neck portion of the lots. Section 7. Section 20-109(4)(h)(4) of the Chanhassen City Code is amended to read as follows: 4. Percent of lot coverage on site broken out by impervious surface and pervious pavement. Section 8. Section 20-109(7)(b) of the Chanhassen City Code is amended to read as follows: b. Calculations and/or drawings that identify the allowable density(number of units or building coverage)under this Code, including lands lying in the primary and secondary zone. Calculation of allowable density shall specifically exclude lands classified as bluffs, floodplains and designated wetlands. Calculation of allowable impervious surface may include bluffs and floodplains but shall specifically exclude designated wetlands. Section 9. Section 20-254(4) of the Chanhassen City Code is amended to read as follows: (4) Lot coverage shall not exceed 70 percent of the site and the remainder is to be suitably landscaped in conformance with article XXV. Section 10. Section 20-485of the Chanhassen City Code is amended to read as follows: Sec. 20-485. - Stormwater management. 2 Lot coverage of lots shall not exceed 25 percent of the lot area, except as follows: (1) Thirty-five percent for medium/high density residential zones; and (2) Seventy percent in industrial zones within the Lake Susan Shoreland District. Section 11. Section 20-490(a)(3) of the Chanhassen City Code is amended to read as follows: (3) The lot coverage does not exceed 25 percent. Section 12. Section 20-490(b)(3) of the Chanhassen City Code is amended to read as follows: (3) Lot coverage must not exceed 25 percent of each lot; and Section 13. Section 20-505(e) of the Chanhassen City Code is amended to read as follows: (e) Lot coverage shall be limited as follows: Comprehensive Lot Plan Designation Coverage (%) Low or medium density residential 30 High density residential 50 Office 70 Commercial (neighborhood or community) 70 Commercial (regional) 70 Industrial 70 Mixed use 70* Individual lots within PUD may exceed these standards as long as the average meets these standards. Section 14. Section 20-575(4) of the Chanhassen City Code is amended to read as follows: (4) The maximum lot coverage is 25 percent, of which no more than 20 percent can be impervious surfaces. Section 15. Section 20-595(4) of the Chanhassen City Code is amended to read as follows: (4) The maximum lot coverage is 25 percent, of which no more than 20 percent can be impervious surfaces. 3 Section 16. Section 20-615(5) of the Chanhassen City Code is amended to read as follows: (5) The maximum lot coverage for all structures and paved surfaces is 30 percent,of which no more than 25 percent can be impervious surfaces. For flag/neck lots neither the area within the neck, nor the lot coverage of the driveway within the neck shall be included within the calculation of the lot area or lot coverage of the lot. Section 17. Section 20-635(4) of the Chanhassen City Code is amended to read as follows: (4) The maximum lot coverage for all structures and paved surfaces is 35 percent, of which no more than 30 percent can be impervious surfaces. I Section 18. Section 20-641 of the Chanhassen City Code is amended to read as follows: Sec. 20-641. - Intent. The intent of the "RLM" district is to provide for single-family attached or detached residential development on land guided residential—low or medium density in the city's comprehensive plan with a maximum net density of eight units per acre. The "RLM" district is intended to be used where large areas of upland will be preserved or created as permanent open space to balance the higher lot coverage permitted on individual lots. Section 19. Section 20-645(4) of the Chanhassen City Code is amended to read as follows: (4) The maximum lot coverage is: a. If a single-family dwelling, 40 percent, of which no more than 35 percent can be impervious surfaces. b. If a two-family dwelling,45 percent of which no more than 40 percent can be impervious surfaces. c. If a townhouse or multiple-family dwelling 50 percent. Section 20. Section 20-905(6) of the Chanhassen City Code is amended to read as follows: (6)Where access doors are proposed from a dwelling to the outdoors,which does not connect directly to a sidewalk or stoop, a minimum ten feet by ten feet area of patio shall be assumed. This patio area must be shown to comply with required property line, lake and wetland setbacks;may not encroach into conservation or drainage and utility easements; and shall not bring the site's lot coverage above that permitted by ordinance. Section 21. Section 20-1072(h) of the Chanhassen City Code is amended to read as follows: (h) Where building sites limit planting, the placement of trees in parkways, gardens, or paved areas is encouraged. Trees should be clustered whenever possible, and consideration shall be given to the special needs of plants surrounded by impervious surfaces. In these 4 I instances,preference is given to surrounding plantings with pervious pavers to allow for the infiltration of stormwater into the root zone. Section 22. The Chanhassen City Code is amended by adding Section 20-921 to read as follows: Sec. 20-921 —Pervious Pavement Properly designed, installed, and maintained pervious pavements have the capacity to allow for stormwater detention and/or infiltration. When not properly designed, installed, and maintained pervious pavements fail to facilitate the detention and/or infiltration of stormwater. Additionally,pervious pavements contribute to the creation of heat islands and do not provide the same surface water managements benefits as native vegetative cover. For these reasons, it is necessary to regulate the lot coverage, design, installation, and maintenance of these systems. 1) Lot Coverage: Pervious pavements are considered to constitute lot coverage; however, they do not constitute impervious surfaces. 2) Location Restrictions: a. Pervious Pavements may not be installed in areas where trash or garbage receptacles will be stored. 3) Installation: a. To meet the City's definition of pervious pavement the system must be designed in compliance with standards established by the Interlocking Concrete Pavement Institute(ICPI) and installed by an ICPI certified installer. b. The City Engineer may permit pervious pavement technologies other than permeable interlocking concrete pavers, so long as the City Engineer determines they are functionally equivalent or better, and the system is designed in compliance with accepted guidelines and is installed by an appropriately certified installer. 4) Maintenance: a. The owner of a pervious paver system must enter into a maintenance agreement with the City to ensure the system performs as designed in perpetuity. This agreement must conform to the manufactures guidelines, and stipulate the frequency and type of maintenance to be performed. Section 23. Section 20-1112(6) of the Chanhassen City Code is amended to read as follows: (6) For A-2,PUD-R for single-family detached houses,RR,RSF,R-4 and RLM for single- family detached residential uses, the width of the driveway access shall not exceed 24 feet at the right-of-way line. No portion of the right-of-way may be paved except that portion used for the driveway. Inside the property line of the site,the maximum driveway width shall not exceed 50 feet. For flag/neck lots the lot coverage of the driveway access within the neck portion of flag/neck lots shall not exceed 33 percent of the neck's area. For all lots the minimum driveway width shall not be less than ten feet. 5 Section 24. Section 20-1181(a) of the Chanhassen City Code is amended to read as follows: (a) When parking lot perimeters where vehicular areas, including driveways and drive aisles, are not entirely screened visually by an intervening building or structure or land mass from any abutting right-of-way, there shall be provided landscaping designed to buffer direct views of cars and vehicular use areas. The landscaping must break up expanses of vehicular use areas,help to visually define boulevards and soften direct views of parking areas and provide for reforestation with overstory tree from the approved tree species list identified for parking or other species as approved by city staff. All new planting areas must have an irrigation system installed. Publicly owned and operated parking lots used for long duration parking may be exempt from this requirement when there is a demonstrated concern regarding security safety. Section 25. Section 20-1408 of the Chanhassen City Code is amended to read as follows: Sec. 20-1408. - Lot coverage Lot coverage, impervious surfaces and pervious pavement, within the bluff setback may contribute to bluff instability due to increased runoff and/or erosion. Lot coverage is prohibited within the bluff setback unless specifically authorized within this article. Section 26. Section 20-1556 of the Chanhassen City Code is amended to read as follows: Sec. 20-1556. - Impervious surface, lot coverage, and slopes. To the greatest extent possible,all development shall minimize the amount of impervious surface by clustering development, using common access drives and utility corridors and minimizing building footprint size. Roads, walkways, bike trails, and parking areas must be designed parallel to natural contours with consideration to maintaining consolidated areas of natural topography and vegetation.Management of surface runoff caused by impervious cover shall be designed using practices delineated in the city's surface water management plan. Within the secondary zone of the BCO district, areas with average slopes exceeding 25 percent shall be preserved in their natural state and maintained as permanent open space.Areas with average slopes less than 25 percent but greater than ten percent shall not exceed 25 percent lot coverage. Lot coverage for areas where average slopes are less than ten percent shall be governed by the underlying zoning district. Section 27. This ordinance shall be effective immediately upon its passage and publication. 6 PASSED AND ADOPTED this [xx] day of[Month], 2017 by the City Council of the City of Chanhassen, Minnesota Todd Gerhardt, City Manager Denny Laufenburger, Mayor (Summary Ordinance [insert number] published in the Chanhassen Villager on [insert date]) 7