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HomeMy WebLinkAboutZOA-17-02PPT for 4/2 CC SS ZOA-17-02 / Site Design Standards City Council Public Hearing April 10, 2017 W li%at icl}� Background - Stormwater • Various local, state and federal laws regarding Stormwater detention — technical in nature • Chapter 26 (zoning and development code) regulates site and building design • Chapter 26 also authorized the CDD to promulgate architectural and site design standards • Does not currently contain any aesthetic design regulations for these facilities lily ail jq-W heat11idgc 04/11/2017 1 PPT for 4/2 CC SS Background — Walls/Grading • Zoning and building code requirements pertaining to retaining wall heights and structure • Minimal code references to site grading more generally • No regulations pertaining to the aesthetic design for retaining walls, nor for grading more generally �„Y 1w W heat R iclw Background • Dec 2016 — CC study session • Jan 2017 — PC study session • March 16 — PC public hearing — approved • March 27 — CC 1St reading — passed • Goals: — Reasonable minimum standards — Context -sensitive designs �� ��'l�x•.it 1 i<hr 04/11/2017 2 PPT for 4/2 CC SS Stormwater Facilities • Required by local, state, federal laws • Often above ground • Technical requirements dictate size and function • Designs can vary — earthen, concrete, integrated Clly M W heat is Stormwater Facilities Regulatory Approach 1. Meet City's drainage standards 2. Codifies planting requirements 3. Visible concrete structures need some treatment 4. Gradual slopes — 4:1 or less 5. Plantings on edge of embankment W heat IJW 04/11/2017 3 PPT for 4/2 CC SS 04/11/2017 PPT for 4/2 CC SS Stormwater Facilities 1. 'T 7 r' ai rr` 04/11/2017 5 PPT for 4/2 CC SS Grading and Walls Public Policy Goals • Minimize visual impacts of walls in public spaces • Encourage use of higher quality materials when highly visible • Encourage use of small walls in lieu of steep and straight slopes • Ensure grades are maintainable • Ensure grades transition logically to adjacent properties and public streets • Maintain flexibility and avoid prescriptive approach ' Wheat w�g, Grading and Walls 1. Pedestrian scaled if adjacent to public space 2. Walls meet applicable building codes 3. Landscaping provided with walls 4. Terraces be sufficient width for plantings 5. Grading appropriate for adjacent ROW/prop 6. Slopes 4:1 or less 7. Rolling transition grades 8. No turf if steeper than 4:1 (IM W Ix:at I icl�n 04/11/2017 R PPT for 4/2 CC SS 04/11/2017 7 Grading and Walls 04/11/2017 7 PPT for 4/2 CC SS Grading and Walls r.......... Recommendation • Proposed to be both codified and in Architectural and Site Design Manual for easy reference • Staff recommends APPROVAL of the proposed ordinance with amendments • As noted, PC recommended approval on March 16 • City Council public hearing on April 10 W Itcat I ziLIlk 04/11/2017 E City or Wheatdge ITEM NO: D� )I DATE: April 10, 2017 REQUEST FOR CITY COUNCIL ACTION i bV,\ V\ p TITLE: COUNCIL BILL NO. 06-2017 — AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES (CASE NO. ZOA-17-02) ® PUBLIC HEARING ❑ ORDINANCES FOR 1 ST READING (03/27/2017) ❑ BIDS/MOTIONS ® ORDINANCES FOR 2ND READING (04/10/2017) ❑ RESOLUTIONS QUASI-JUDICIAL: ❑ YES ® NO I. Community De ,elopment Director City Manager ISSUE: The City's zoning code currently regulates the design of buildings, landscaping, and parking, but fails to address site grading, stormwater facilities, and retaining walls—all of which can be equally visible elements. The goal of this code amendment is to establish reasonable minimum standards that promote context -sensitive designs for these features. PRIOR ACTION: After witnessing a series of new development projects with substandard designs for stormwater facilities and retaining walls, staff posed the question to City Council as to whether it is appropriate to establish minimum design standards for these features. The issue was discussed with City Council at a study session on December 5, 2016 and with Planning Commission on January 5, 2017. At both meetings, staff proposed a regulatory framework and provided photographic examples of average and upgraded designs. At a public hearing on March 16, 2017, Planning Commission voted to recommend approval of the proposed ordinance, and draft meeting minutes from the public hearing are enclosed. On March 27, 2017, City Council approved the ordinance on first reading by a vote of 4-1. Council Action Form — Site Design Amendments April 10, 2017 Page 2 FINANCIAL IMPACT: The proposed ordinance is not expected to have a financial impact on the City. BACKGROUND: The enclosed ordinance represents a reasonable regulatory balance by promoting higher quality designs, but not being overly burdensome. Proposed Regulations — Stormwater Facilities The purpose of a stormwater facility is to accommodate runoff that results from the impervious surfaces of a development. In some cases, these facilities are constructed below ground, but most often, they are above ground and are visible. Because of requirements to detain stormwater on site for a certain period of time, these facilities often include some type of basin or pond. In some instances, these basins are earthen ponds and in other cases they are constructed from concrete and represent a stark contrast to the natural features and well -articulated structures on a site. The purpose of the proposed regulations is to ensure that stormwater facilities are better integrated into site development and further, that they enhance development through thoughtful design. This could include landscaping, rocks, or surface treatments to concrete structures. Historically, best practice has guided the types of plantings that can be included in stormwater areas, but codified standards will provide more clarity for developers and their design teams. Based on input from Planning Commission, the requirement for upgraded concrete structures is only applicable when visible from a public street or public space. Proposed Regulations — Site Grading and Retaining Walls Because site grading and retaining walls are interrelated, it is proposed they be addressed together. The purpose of the new regulations is to require grading and wall designs that respect existing topography and surrounding properties. The design standards for retaining walls respond to several recent developments where tall retaining walls have been installed immediately adjacent to sidewalks and have created uncomfortable pedestrian environments. The proposed ordinance requires that in public spaces, walls and elevation changes be scaled to the pedestrian by using terracing, landscaping, and material changes. For visual and maintenance reasons, steep slopes are explicitly not permitted. In the spirit of promoting more context -sensitive designs, grading plans must consider the impact to current and future development and rights-of-way. In response to Planning Commission's recommendation, the ordinance includes a provision restricting turf grass on slopes steeper than 4:1 which, among other things, is difficult to establish and maintain. Applicability These new design standards would apply to new site development in all zone districts, to expansions of stormwater facilities or retaining walls of 15% or more, and to substantial Council Action Form — Site Design Amendments April 10, 2017 Page 3 modifications of stormwater facilities, walls, or site grading. It is proposed the ordinance be located in Article V of the zoning code, which addresses design standards such as landscape, parking and lighting. If the ordinance is approved, the provisions will also be included in the Architectural and Site Design Manual (ASDM), which supplements the zoning code. This document includes photographs and descriptive captions that will help to communicate the standards. Attachment 2 is an excerpt from the ASDM for reference purposes. RECOMMENDATIONS: Staff recommends approval of the ordinance. RECOMMENDED MOTION: "I move to approve Council Bill No. 06-2017, an ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities, on second reading and that it take effect 15 days after final publication." Or, "I move to postpone indefinitely Council Bill No. 06-2017, an ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities, for the following reason(s) REPORT PREPARED BY: Lauren Mikulak, Senior Planner Kenneth Johnstone, Community Development Director Patrick Goff, City Manager ATTACHMENTS: 1. Council Bill No. 06-2017 2. Draft Meeting Minutes — March 16, 2017 Planning Commission Public Hearing 3. Excerpt from the Architectural and Site Design Manual CITY OF WHEAT RIDGE, COLORADO INTRODUCED BY COUNCIL MEMBER DURAN COUNCIL BILL NO. 06 ORDINANCE NO. Series 2017 TITLE: AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES WHEREAS, the City of Wheat Ridge is a home rule municipality operating under a charter adopted pursuant to Article XX of the Colorado Constitution and vested with the authority by that article and the Colorado Revised Statutes to adopt ordinances for the regulation of land use and protection of the public health, safety and welfare; and WHEREAS, in exercise of that authority, the City Council of the City of Wheat Ridge has previously enacted Chapter 26 of the Wheat Ridge Code of Laws pertaining to zoning, land use, and development; and WHEREAS, Chapter 26 includes regulations to ensure that site grading, retaining walls, and stormwater facilities comply with all technical requirements; and WHEREAS, the City Council recognizes the need for elevating certain site design standards related to site grading, retaining walls, and stormwater facilities; and WHEREAS, the City Council finds that elevating these standards will improve the quality of development projects throughout the City; NOW THEREFORE BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF WHEAT RIDGE, COLORADO: Section 1. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-507, to read in its entirety as follows: SEC. 26-507. STORMWATER FACILITIES. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT STORMWATER FACILITIES ARE INTEGRATED INTO SITE DEVELOPMENT AND ARE DESIGNED TO ENHANCE THE DEVELOPMENT THROUGH THE USE OF INNOVATIVE OR LOW IMPACT DESIGN APPROACHES AND THROUGH THE USE OF MATERIALS AND LANDSCAPING THAT COMPLEMENT THE SURROUNDINGS. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS; Attachment 1 2. SUBSTANTIAL MODIFICATION OF EXISTING STORMWATER FACILITIES OR EXPANSION OF SUCH FACILITIES BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. ALL STORMWATER FACILITIES SHALL BE DESIGNED AND MAINTAINED IN ACCORDANCE WITH THE CITY'S CURRENT SITE DRAINAGE REQUIREMENTS. 2. BELOW THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION, PLANT MATERIAL SHALL BE LIMITED TO WETLAND PLANTINGS, GRASSES, OR OTHER GROUNDCOVERS THAT ENHANCE WATER QUALITY AND ARE APPROPRIATE BASED ON PERIODIC FLOODING AND FACILITY MAINTENANCE NEEDS. TREES AND SHRUBS MAY BE PLANTED ABOVE THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION. 3. FOR CONCRETE STRUCTURES OR BASINS THAT ARE VISIBLE FROM A PUBLIC STREET OR PUBLIC SPACE, ROCKS, LANDSCAPING, AND/OR DECORATIVE CONCRETE SURFACE TREATMENTS SHALL BE UTILIZED TO SOFTEN THEIR APPEARANCE. 4. THE SIDE SLOPES OF STORMWATER FACILITIES SHOULD BE GRADUAL, AND GENERALLY LIMITED TO 4:1 OR LESS. 5. THE TOP EDGE OF SLOPES AND EMBANKMENTS SHOULD BE LANDSCAPED WITH GROUPINGS OF TREES AND SHRUBS. THIS SHALL NOT BE CONSTRUED TO MEAN TREES SPACED ON CENTER. PLANTINGS SHOULD BE LOCATED TO ALLOW MAINTENANCE ACCESS AS NEEDED. Section 2. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-508, to read in its entirety as follows: SEC. 26-508. SITE GRADING AND RETAINING WALLS. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT GRADING DESIGNS RESPECT EXISTING TOPOGRAPHY AND ARE SENSITIVE TO EXISTING LANDFORMS AND THE SURROUNDING PROPERTIES. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS. 2. SUBSTANTIAL MODIFICATION OF EXISTING RETAINING WALLS OR SITE GRADING OR EXPANSION SUCH WALLS BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. WALLS AND ELEVATION CHANGES THAT ARE ADJACENT TO PUBLIC SPACES SHALL BE DESIGNED TO PROVIDE A PEDESTRIAN SCALED ENVIRONMENT THROUGH THE USE OF TERRACING, LANDSCAPING, AND/OR MATERIAL VARIATION. 2. ALL RETAINING WALLS SHALL BE BUILT PER THE REQUIREMENTS OF ANY APPLICABLE CODES, INCLUDING BUT NOT LIMITED TO THE TECHNICAL CODES ADOPTED BY THE CITY AND CONTAINTED IN CHAPTER 5 OF THIS CODE. 3. LANDSCAPING SHALL BE PROVIDED IN COMBINATION WITH RETAINING WALLS TO SOFTEN THE APPEARANCE OF WALLS. 4. ALL TERRACED PLANTING AREAS BETWEEN WALLS SHALL BE OF SUFFICIENT WIDTH TO SUPPORT VEGETATION AND ROOT SYSTEMS. 5. SITE GRADING SHALL NOT ADVERSELY IMPACT ADJACENT PROPERTY AND/OR RIGHTS-OF-WAY. GRADING SHALL ANTICIPATE FUTURE DEVELOPMENT AND SHALL INTEGRATE WITH ADJACENT PROPERTY AND/OR RIGHT-OF-WAY. 6. SLOPES STEEPER THAN 3:1 ARE NOT PERMITTED. GRADES OF 4:1 OR LESS ARE ENCOURAGED. 7. TRANSITION GRADES SHOULD BE ROLLING AND NATURAL RATHER THAN ONE CONTINUOUS STRAIGHT LINE. 8. TURF GRASS SHOULD NOT BE USED ON SLOPES STEEPER THAN 4:1. Section 3. Section 26-1110 of the Code, concerning site design requirements in the mixed use zone districts, is hereby amended by the addition of two (2) new subsections, J and K, to read in their entirety as follows: J. THE REQUIREMENTS OF SECTION 26-507 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. K. THE REQUIREMENTS OF SECTION 26-508 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. Section 4. Severability, Conflicting Ordinances Repealed. If any section, subsection or clause of this Ordinance shall be deemed to be unconstitutional or otherwise invalid, the validity of the remaining sections, subsections and clauses shall not be affected thereby. All other ordinances or parts of ordinances in conflict with the provisions of this Ordinance are hereby repealed. Section 5. Effective Date. This ordinance shall take effect fifteen (15) days after final publication, as provided by Section 5.11 of the Charter. INTRODUCED, READ, AND ADOPTED on first reading by a vote of 4 to 1, this 27th day of March, 2017 and ordered published in full in a newspaper of general circulation in the City of Wheat Ridge, and Public Hearing and consideration on final passage set for April 10, 2017 at 7:00 p.m., in the Council Chambers, 7500 West 29th Avenue, Wheat Ridge, Colorado. READ ADOPTED AND ORDERED PUBLISHED on second and final reading by a vote of to , this day of 2017. SIGNED by the Mayor on this day of 12017. Joyce Jay, Mayor ATTEST: Janelle Shaver, City Clerk Approved as to Form Gerald E. Dahl, City Attorney First Publication: March 30, 2017 Second Publication: Wheat Ridge Transcript Effective Date: Published: Wheat Ridge Transcript and www.ci.wheatridge.co.us 1. 2. 3. 4. 5. 6. City Of ' WheatRidge PLANNING COMMISSION Minutes of Meeting March 16, 2017 CALL THE MEETING TO ORDER The meeting was called to order by Chair OHM at 7:01 p.m in the City Council Chambers of the Municipal Budding, 7500 West 291h Avenue, Wheat Ridge, Colorado. ROLL CALL OF MEMBERS Commission Members Present: Commission Members Absent: Staff Members Present: PLEDGE OF ALLEGIANCE Dirk Boden Emery Dorsey Donna Kimsey Janet Leo Scott Ohm Vivian Vos Alan Bucknam Amanda Weaver Lauren Mikulak, Senior Planner Tammy Odean, Recording Secretary APPROVE ORDER OF THE AGENDA It was moved by Commissioner KIMSEY and seconded by Commissioner LEO to approve the order of the agenda. Motion carried 6-0. APPROVAL OF MINUTES — March 2, 2017 It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to approve the minutes of March 2, 2017, as written. Motion passed 6-0. PUBLIC FORUM (This is the time for any person to speak on any subject not appearing on the agenda.) No one wished to speak at this time. Planning Commission Minutes March 16, 2017 Attachment 2 1 7. PUBLIC HEARING A. Case No. ZOA-17-01: An ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of small-scale alcohol production facilities. Ms. Mikulak gave a short presentation regarding the proposed ordinance. She entered into the record the contents of the case file, zoning code and the draft ordinance. She stated public notice requirements have been met, therefore the Planning Comnission has jurisdiction to hear this case. The Commissioners did not have any questions for Ms. Mikulak. It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to recommend approval of the proposed ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of small-scale alcohol production facilities. Motion carried 6-0. B. Case No. ZOA-17-02: An ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities. Ms. Mikulak gave a short presentation regarding the proposed ordinance. She entered into the record the contents of the case file, zoning code, the contents of the digital presentation and the draft ordinance. She stated public notice requirements have been met, therefore the Planning Commission has jurisdiction to hear this case. Conrnnissioner VOS asked if detention ponds will be adjacent to impervious surfaces and if staff will get to view the developer's plans. Ms. Mikulak stated that a pond may or may not be adjacent to the impervious surface depending on the topography and design of the site. Typically, a pond is located on the the downhill side of a site, so it may or may not be visible. She also explained that staff will see the developer's plans. Commissioner VOS also asked if this ordinance will apply retroactively to the substandard designs that already exist. Ms. Mikulak explained that there will be no provision to make current facilities retroactive, but staff will be enforcing landscape maintenance to ensure that what exists is maintained. Planning Commission Minutes -2— March 2— March 16, 2017 Chair OHM asked if there is a maximum wall height for retaining walls. Ms. Mikulak explained it depends on the type of application. If it is a divisional height, it might be 4 to 6 feet, but if it is required because of the topography of the site that functional purpose night trump the maximum height. In some cases, setbacks night be applied. Chair OHM also asked if walls are allowed on all four side of a detention facility. He also asked about the height of the walls around the facility for fear of anyone falling in and not being able to get out because the walls surrounding are too high. For life safety reasons, Chair OHM suggested terracing around the detention pond so there is not four vertical walls. Ms. Mkulak said she is not aware of anything that prolubits walls on all four sides and the City follows Urban Drainage as guidelines. It was moved by Commissioner LEO and seconded by Commissioner DORSEY to recommend approval of the proposed ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities. Chair OHM commented that he would like staff to consider life safety implications when reviewing drainage designs. Motion carried 6-0. 8. OTHER ITEMS A. Election of Officers New officers were elected by secret ballot: Chair: Commissioner OHM Vice Chair: Commissioner BODEN B. Ms. Mikulak let the Commission know that staffs new Planner Technician is Scott Cutler. There will be no meeting on April 6. 9. ADJOURNMENT It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to adjourn the meeting at 7:27 p.m. Motion passed 6-0. Scott Ohm, Chair Tammy Odean, Recording Secretary Planning Commission Minutes -3— March 3— March 16, 2017 3.9 Stormwater Facilities Design Principle: Stormwater facilities should be integrated into site development and be designed to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. Design Standards: 1. All Stormwater facilities shall be designed and maintained in accordance with the City's current Site Drainage Requirements. 2. Below the 5 -year stormwater surface elevation, plant material is limited to wetland plantings, grasses, or other groundcovers that enhance water quality and are appropriate based on periodic flooding and facility maintenance needs. Trees and shrubs may be planted above the 5 -year stormwater surface elevation. 3. For concrete structures or basins that are visible from a public street or public space, rocks, landscaping, and/or decorative concrete surface treatments shall be utilized to soften their appearance. Design Guidelines: 4. The side slopes of Stormwater facilities should be gradual, and generally limited to 4:1 or less. 5. The top edge of slopes and embankments should be landscaped with groupings of trees and shrubs. Plantings should be located to allow maintenance access as needed. Chapter 3 - Site Design Stormwater Facilities. Rocks and wetland plantings make this drainage channel a visual amenity that complements the area. Stormwater Facilities. Trees, wetland plantings, and stone walls (natural or stamped) soften Stormwater facilities that are visible from a public street. Attachment 3 Wheat Ridge Architectural and Site Design Manual 17 Site Grading and Retaining Walls. A pedestrian scaled environment shall be provided when walls and elevation changes are next to public space. Site Grading and Retaining Walls. Large grade changes can be accommodated in an attractive manner through the use of terraces and landscaping. Rolling Slope stroi9ht \ Slope Site Grading and Retaining Walls. Transition grades should be rolling rather than one continuous straight line. 3.10 Site Grading and Retaining Walls Design Principle: Grading designs should respect the existing topography and be sensitive to existing landforms and surrounding properties. Design Standards: 1. Walls and elevation changes that are adjacent to public spaces shall be designed to provide a pedestrian scaled environment through the use of terracing, landscaping, and/or material variation. 2. All retaining walls shall be built per the requirements of the applicable building codes. 3. Landscaping shall be provided in combination with retaining walls to soften their appearance. 4. All terraced planting areas between walls shall be of sufficient width to support vegetation and root systems. 5. Site grading shall not adversely impact adjacent property and/ or right-of-way, and shall anticipate future development and integration of adjacent property and/or right-of-way. 6. Grades of 4:1 or less are encouraged, slopes steeper than 3:1 are not permitted. Design Guidelines: 7. Transition grades should be rolling and natural rather than one continuous straight line. 8. Turf grass should not be used on slopes steeper than 4:1. 18 Wheat Ridge Architectural and Site Design Manual F � City of j Wheat RAA PLANNING COMMUNITY DEVELOPMENT MEETING DATE: March 16, 2017 TITLE: AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES CASE NO. ZOA-17-02 V C/ ® PUBLIC HEARING Case Manager: Lauren Mikulak Date of Preparation: March 8, 2017 ® CODE CHANGE ORDINANCE SUMMARY: The City's zoning code currently regulates the design of buildings, landscaping, and parking, but fails to address site grading, stormwater facilities, and retaining walls—all of which can be equally visible elements. The goal of this code amendment is to establish reasonable minimum standards that promote context -sensitive designs for these features. Notice for this public hearing was provided by the Code of Laws. BACKGROUND: After witnessing a series of new development projects with substandard designs for stormwater facilities and retaining walls, staff posed the question to City Council as to whether it is appropriate to establish minimum design standards for these features. The issue was discussed with City Council at a study session on December 5, 2016 and with Planning Commission on January 5, 2017. At both meetings, staff proposed a regulatory framework and provided photographic examples of average and upgraded designs. The enclosed ordinance represents a reasonable regulatory balance by promoting higher quality designs, but not being overly burdensome. The ordinance includes several new provisions that were recommended by Planning Commission in the January meeting. Proposed Regulations – Stormwater Facilities The purpose of a stormwater facility is to accommodate runoff that results from the impervious surfaces of a development. In some cases, these facilities are constructed below ground, but most often, they are above ground and are visible. Because of requirements to detain stormwater on site for a certain period of time, these facilities often include some type of basin or pond. In some instances, these basins are earthen ponds and in other cases they are constructed from concrete and represent a stark contrast to the natural features and well -articulated structures on a site. The purpose of the proposed regulations is to ensure that stormwater facilities are better integrated into site development, and further that they enhance development through thoughtful design. This could include landscaping, rocks, or surface treatments to concrete structures. Historically, best practice has guided the types of plantings that can be included in stormwater areas, but codified standards will provide more clarity for developers and their design teams. Based on input from Planning Commission, the requirement for upgraded concrete structures is only applicable when visible from a public street or public space. Proposed Regulations — Site Grading and Retaining Walls Because site grading and retaining walls are interrelated, they are proposed to be addressed together. The purpose of the new regulations is to require grading and wall designs that respect existing topography and surrounding properties. The design standards for retaining walls respond to several recent developments where tall retaining walls have been installed immediately adjacent to sidewalks and have created uncomfortable pedestrian environments. The proposed ordinance requires that in public spaces, walls and elevation changes be scaled to the pedestrian using terracing, landscaping, and material changes. For visual and maintenance reasons, steep slopes are explicitly not permitted. In the spirit of promoting more context -sensitive designs, grading plans must consider the impact to current and future development and rights-of-way. In response to Planning Commission's recommendation, the ordinance includes a provision restricting turf grass on slopes steeper than 4:1 which, among other things, is difficult to establish and maintain. Applicability These new design standards would apply to new site development in all zone districts; to expansions of stormwater facilities or retaining walls of 15% or more; and to substantial modifications of stormwater facilities, walls, or site grading. The ordinance is proposed to be located in Article V of the zoning code, which addresses design standards such as landscape, parking and lighting. If the ordinance is approved, the provisions will also be included in the Architectural and Site Design Manual (ASDM), which supplements the zoning code. This document include photographs and descriptive captions which will help to communicate the standards. This excerpt from the ASDM is enclosed for reference. RECOMMENDED MOTION: "I move to recommend approval of the proposed ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities." ZOA-17-02 / Site Design Standards Exhibits: 1. Proposed Ordinance 2. Excerpt from the Architectural and Site Design Manual ZOA-17-02 / Site Design Standards CITY OF WHEAT RIDGE, COLORADO INTRODUCED BY COUNCIL MEMBER COUNCIL BILL NO. ORDINANCE NO. Series 2017 TITLE: AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES WHEREAS, the City of Wheat Ridge ("City") is a home rule municipality operating under a charter adopted pursuant to Article XX of the Colorado Constitution and vested with the authority by that article and the Colorado Revised Statutes to adopt ordinances for the regulation of land use and protection of the public health, safety and welfare; and WHEREAS, in exercise of that authority, the City Council of the City of Wheat Ridge has previously enacted Chapter 26 of the Wheat Ridge Code of Laws (the "Code") pertaining to zoning, land use, and development; and WHEREAS, Chapter 26 includes regulations to ensure that site grading, retaining walls, and stormwater facilities comply with all technical requirements; and WHEREAS, the City Council recognizes the need for elevating certain site design standards related to site grading, retaining walls, and stormwater facilities; and WHEREAS, the City Council finds that elevating these standards will improve the quality of development projects throughout the City; and NOW THEREFORE BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF WHEAT RIDGE, COLORADO: Section 1. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-507, to read in its entirety as follows: SEC. 26-507. STORMWATER FACILITIES. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT STORMWATER FACILITIES ARE INTEGRATED INTO SITE DEVELOPMENT AND ARE DESIGNED TO ENHANCE THE DEVELOPMENT THROUGH THE USE OF INNOVATIVE OR LOW IMPACT DESIGN APPROACHES AND THROUGH THE USE OF MATERIALS AND LANDSCAPING THAT COMPLEMENT THE SURROUNDINGS. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS; 2. SUBSTANTIAL MODIFICATION OF EXISTING STORMWATER FACILITIES OR EXPANSION OF SUCH FACILITIES BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. ALL STORMWATER FACILITIES SHALL BE DESIGNED AND MAINTAINED IN ACCORDANCE WITH THE CITY'S CURRENT SITE DRAINAGE REQUIREMENTS. 2. BELOW THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION, PLANT MATERIAL SHALL BE LIMITED TO WETLAND PLANTINGS, GRASSES, OR OTHER GROUNDCOVERS THAT ENHANCE WATER QUALITY AND ARE APPROPRIATE BASED ON PERIODIC FLOODING AND FACILITY MAINTENANCE NEEDS. TREES AND SHRUBS MAY BE PLANTED ABOVE THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION. 3. FOR CONCRETE STRUCTURES OR BASINS THAT ARE VISIBLE FROM A PUBLIC STREET OR PUBLIC SPACE, ROCKS, LANDSCAPING, AND/OR DECORATIVE CONCRETE SURFACE TREATMENTS SHALL BE UTILIZED TO SOFTEN THEIR APPEARANCE. 4. THE SIDE SLOPES OF STORMWATER FACILITIES SHOULD BE GRADUAL, AND GENERALLY LIMITED TO 4:1 OR LESS. 5. THE TOP EDGE OF SLOPES AND EMBANKMENTS SHOULD BE LANDSCAPED WITH GROUPINGS OF TREES AND SHRUBS. THIS SHALL NOT BE CONSTRUED TO MEAN TREES SPACED ON CENTER. PLANTINGS SHOULD BE LOCATED TO ALLOW MAINTENANCE ACCESS AS NEEDED. Section 2. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-508, to read in its entirety as follows: SEC. 26-508. SITE GRADING AND RETAINING WALLS. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT GRADING DESIGNS RESPECT EXISTING TOPOGRAPHY AND ARE SENSITIVE TO EXISTING LANDFORMS AND THE SURROUNDING PROPERTIES. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS. 2. SUBSTANTIAL MODIFICATION OF EXISTING RETAINING WALLS OR SITE GRADING OR EXPANSION SUCH WALLS BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. WALLS AND ELEVATION CHANGES THAT ARE ADJACENT TO PUBLIC SPACES SHALL BE DESIGNED TO PROVIDE A PEDESTRIAN SCALED ENVIRONMENT THROUGH THE USE OF TERRACING, LANDSCAPING, AND/OR MATERIAL VARIATION. 2. ALL RETAINING WALLS SHALL BE BUILT PER THE REQUIREMENTS OF ANY APPLICABLE CODES, INCLUDING BUT NOT LIMITED TO THE TECHNICAL CODES ADOPTED BY THE CITY AND CONTAINTED IN CHAPTER 5 OF THIS CODE. 3. LANDSCAPING SHALL BE PROVIDED IN COMBINATION WITH RETAINING WALLS TO SOFTEN THE APPEARANCE OF WALLS. 4. ALL TERRACED PLANTING AREAS BETWEEN WALLS SHALL BE OF SUFFICIENT WIDTH TO SUPPORT VEGETATION AND ROOT SYSTEMS. 5. SITE GRADING SHALL NOT ADVERSELY IMPACT ADJACENT PROPERTY AND/OR RIGHTS-OF-WAY. GRADING SHALL ANTICIPATE FUTURE DEVELOPMENT AND SHALL INTEGRATE WITH ADJACENT PROPERTY AND/OR RIGHT-OF-WAY. 6. SLOPES STEEPER THAN 3:1 ARE NOT PERMITTED. GRADES OF 4:1 OR LESS ARE ENCOURAGED. 7. TRANSITION GRADES SHOULD BE ROLLING AND NATURAL RATHER THAN ONE CONTINUOUS STRAIGHT LINE. 8. TURF GRASS SHOULD NOT BE USED ON SLOPES STEEPER THAN 4:1. Section 3. Section 26-1110 of the Code, concerning site design requirements in the mixed use zone districts, is hereby amended by the addition of two (2) new subsections, J and K, to read in their entirety as follows: J. THE REQUIREMENTS OF SECTION 26-507 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. K. THE REQUIREMENTS OF SECTION 26-508 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. Section 4. Severability, Conflicting Ordinances Repealed. If any section, subsection or clause of this Ordinance shall be deemed to be unconstitutional or otherwise invalid, the validity of the remaining sections, subsections and clauses shall not be affected thereby. All other ordinances or parts of ordinances in conflict with the provisions of this Ordinance are hereby repealed. Section 5. Effective Date. This ordinance shall take effect fifteen (15) days after final publication, as provided by Section 5.11 of the Charter. INTRODUCED, READ, AND ADOPTED on first reading by a vote of to , this _th day of , 2017 and ordered published in full in a newspaper of general circulation in the City of Wheat Ridge, and Public Hearing and consideration on final passage set for , 2017 at 7:00 p.m., in the Council Chambers, 7500 West 29th Avenue, Wheat Ridge, Colorado. READ ADOPTED AND ORDERED PUBLISHED on second and final reading by a vote of to , this day of 2017. SIGNED by the Mayor on this day of 2017. Joyce Jay, Mayor ATTEST: Janelle Shaver, City Clerk Approved as to Form Gerald E. Dahl, City Attorney First Publication: Second Publication: Wheat Ridge Transcript Effective Date: Published: Wheat Ridge Transcript and www.ci.wheatridge.co.us 3.9 Stormwater Facilities Design Principle: Stormwater facilities should be integrated into site development and be designed to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. Design Standards: 1. All Stormwater facilities shall be designed and maintained in accordance with the City's current Site Drainage Requirements. 2. Below the 5 -year stormwater surface elevation, plant material is limited to wetland plantings, grasses, or other groundcovers that enhance water quality and are appropriate based on periodic flooding and facility maintenance needs. Trees and shrubs may be planted above the 5 -year stormwater surface elevation. 3. For concrete structures or basins that are visible from a public street or public space, rocks, landscaping, and/or decorative concrete surface treatments shall be utilized to soften their appearance. Design Guidelines: 4. The side slopes of stormwater facilities should be gradual, and generally limited to 4:1 or less. 5. The top edge of slopes and embankments should be landscaped with groupings of trees and shrubs. Plantings should be located to allow maintenance access as needed. Chapter 3 - Site Design Stormwater Facilities. Rocks and wetland plantings make this drainage channel a visual amenity that complements the area. Stormwater Facilities. Trees, wetland plantings, and stone walls (natural or stamped) soften stormwater facilities that are visible from a public street. Wheat Ridge Architectural and Site Design Manual 17 Site Grading and Retaining Walls. A pedestrian scaled environment shall be provided when walls and elevation changes are next to public space. Site Grading and Retaining Walls. Large grade changes can be accommodated in an attractive manner through the use of terraces and landscaping. Rolling \ Slope Stroi9 et\ Slop \_ Site Grading and Retaining Walls. Transition grades should be rolling rather than one continuous straight line. 3.10 Site Grading and Retaining Walls Design Principle: Grading designs should respect the existing topography and be sensitive to existing landforms and surrounding properties. Design Standards: 1. Walls and elevation changes that are adjacent to public spaces shall be designed to provide a pedestrian scaled environment through the use of terracing, landscaping, and/or material variation. 2. All retaining walls shall be built per the requirements of the applicable building codes. 3. Landscaping shall be provided in combination with retaining walls to soften their appearance. 4. All terraced planting areas between walls shall be of sufficient width to support vegetation and root systems. 5. Site grading shall not adversely impact adjacent property and/ or right-of-way, and shall anticipate future development and integration of adjacent property and/or right-of-way. 6. Grades of 4:1 or less are encouraged, slopes steeper than 3:1 are not permitted. Design Guidelines: 7. Transition grades should be rolling and natural rather than one continuous straight line. 8. Turf grass should not be used on slopes steeper than 4:1. 18 Wheat Ridge Architectural and Site Design Manual W 0 N O • • ® • N N 0 --I p � m rD Ln < n n C a- 0 = O CD N N ;:p-0 n n rt Q N Ln o Z v ao Q \C G r -r CD E�_ � _0 � O v V o rD n 0q omm Q.. N n N CD N N 0- Q O - — O O r�-r n � N r CL .� CD (D -� Q o (D n i vO rD �3D` a' r* m rt �rDQ 0 h F' C M CD CD 0 rn+ N (n ` n 0 Ln O r+ Q 3 Q n v rD N rD rD � r+ O m v 3 N (5 (A 0 °- CD E N nu rt M r+ r F w '' m CD - _ A �- O (fl W 0 N O Cn N o !-Al N N • c� m rD Ln < n vN C a- 0 = O CD CD N O CD n n rt Q N Ln o Z v ao Q \C G r -r c E�_ � _0 � O v V o rD n 0q omm Q.. 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Y r�r O 0 v rt_ V 4 N nO C)- m Ln N 7 - 0 N _0 Yip O n ry _0 (D N O O N O A) v � � � 0 � N) C) C) cf) cn 0 � 0 111i 0 ol r) o un o / = n j \ \ / 5 7 ] 2 n 0 7 CD- 2 C: 0- r \ ? � ƒ & 0- -0 CL \ \ 0 §. n = = � n / 0 @rD/ 3 o _0 n � _ 2 \ \ LA ( r+ CL 1 7 0 > � � � � 0 � N) C) C) cf) cn 0 � 0 111i 0 ol 1. N 3. 4. 5. 6. v ►/� I City of WheatP,ide PLANNING COMMISSION Minutes of Meeting March 16, 2017 CALL THE MEETING TO ORDER The meeting was called to order by Chair OHM at 7:01 p.m in the City Council Chambers of the Municipal Building, 7500 West 291h Avenue, Wheat Ridge, Colorado. ROLL CALL OF MEMBERS Commission Members Present: Commission Members Absent Staff Members Present: PLEDGE OF ALLEGIANCE Dirk Boden Emery Dorsey Donna Kimsey Janet Leo Scott Ohm Vivian Vos Alan Bucknam Amanda Weaver Lauren Mikulak, Senior Planner Tammy Odean, Recording Secretary APPROVE ORDER OF THE AGENDA It was moved by Commissioner KIMSEY and seconded by Commissioner LEO to approve the order of the agenda. Motion carried 6-0. APPROVAL OF MINUTES — March 2, 2017 It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to approve the minutes of March 2, 2017, as written. Motion passed 6-0. PUBLIC FORUM (This is the time for any person to speak on any subject not appearing on the agenda.) No one wished to speak at this time. Planning Commission Minutes March 16, 2017 -1— 7. PUBLIC HEARING A. Case No. ZOA-17-01: An ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of small-scale alcohol production facilities. Ms. Mikulak gave a short presentation regarding the proposed ordinance. She entered into the record the contents of the case file, zoning code and the draft ordinance. She stated public notice requirements have been met, therefore the Planning Commission has jurisdiction to hear this case. The Commissioners did not have any questions for Ms. Mikulak. It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to recommend approval of the proposed ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of small-scale alcohol production facilities. Motion carried 6-0. B. Case No. ZOA-17-02: An ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities. Ms. Mikulak gave a short presentation regarding the proposed ordinance. She entered into the record the contents of the case file, zoning code, the contents of the digital presentation and the draft ordinance. She stated public notice requirements have been met, therefore the Planning Commission has jurisdiction to hear this case. Commissioner VOS asked if detention ponds will be adjacent to impervious surfaces and if staff will get to view the developer's plans. Ms. Mikulak stated that a pond may or may not be adjacent to the impervious surface depending on the topography and design of the site. Typically, a pond is located on the the downhill side of a site, so it may or may not be visible. She also explained that staff will see the developer's plans. Commissioner VOS also asked if this ordinance will apply retroactively to the substandard designs that already exist. Ms. Mikulak explained that there will be no provision to make current facilities retroactive, but staff will be enforcing landscape maintenance to ensure that what exists is maintained. Planning Commission Minutes -2— March 2— March 16, 2017 Chair OHM asked if there is a maximum wall height for retaining walls. Ms. Mikulak explained it depends on the type of application. If it is a divisional height, it might be 4 to 6 feet, but if it is required because of the topography of the site that functional purpose might trump the maximum height. In some cases, setbacks might be applied. Chair OHM also asked if walls are allowed on all four side of a detention facility. He also asked about the height of the walls around the facility for fear of anyone falling in and not being able to get out because the walls surrounding are too high. For life safety reasons, Chair OHM suggested terracing around the detention pond so there is not four vertical walls. Ms. Mikulak said she is not aware of anything that prohibits walls on all four sides and the City follows Urban Drainage as guidelines. It was moved by Commissioner LEO and seconded by Commissioner DORSEY to recommend approval of the proposed ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities. Chair OHM comniented that he would like staff to consider life safety implications when reviewing drainage designs. Motion carried 6-0. S. OTHER ITEMS A. Election of Officers New officers were elected by secret ballot: Chair: Comms ssioner OHM Vice Chair: Commissioner BODEN B. Ms. Mikulak let the Commission know that staffs new Planner Technician is Scott Cutler. There will be no meeting on April 6. 9. ADJOURNMENT It was moved by Commissioner DORSEY and seconded by Commissioner KIMSEY to adjourn the meeting at 7:27 p.m. Motion passed 6-0. Scott Ohm, Chair Planning Commission Minutes March 16, 2017 Tammy Odean, Recording Secretary -3— City of W heat Rijge L ITEM NO: . DATE: March 27, 2017 REQUEST FOR CITY COUNCIL ACTION TITLE: COUNCIL BILL NO. 06-2017 - AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES (CASE NO. ZOA-17-02) ❑ PUBLIC HEARING ® ORDINANCES FOR 1 ST READING (03/27/2017) ❑ BIDS/MOTIONS ❑ ORDINANCES FOR 2ND READING (04/10/2017) ❑ RESOLUTIONS QUASI-JUDICIAL: ❑ YES ® NO P Community De4elopment Director City Manager ISSUE: The City's zoning code currently regulates the design of buildings, landscaping, and parking, but fails to address site grading, stormwater facilities, and retaining walls—all of which can be equally visible elements. The goal of this code amendment is to establish reasonable minimum standards that promote context -sensitive designs for these features. PRIOR ACTION: After witnessing a series of new development projects with substandard designs for stormwater facilities and retaining walls, staff posed the question to City Council as to whether it is appropriate to establish minimum design standards for these features. The issue was discussed with City Council at a study session on December 5, 2016 and with Planning Commission on January 5, 2017. At both meetings, staff proposed a regulatory framework and provided photographic examples of average and upgraded designs. At a public hearing on March 16, 2017, Planning Commission voted to recommend approval of the proposed ordinance; meeting minutes from the public hearing will be included with the ordinance for second reading. Council Action Form — Site Design Amendments March 27, 2017 Page 2 FINANCIAL IMPACT: The proposed ordinance is not expected to have a financial impact on the City. BACKGROUND: The enclosed ordinance represents a reasonable regulatory balance by promoting higher quality designs, but not being overly burdensome. Proposed Regulations — Stormwater Facilities The purpose of a stormwater facility is to accommodate runoff that results from the impervious surfaces of a development. In some cases, these facilities are constructed below ground, but most often, they are above ground and are visible. Because of requirements to detain stormwater on site for a certain period of time, these facilities often include some type of basin or pond. In some instances, these basins are earthen ponds and in other cases they are constructed from concrete and represent a stark contrast to the natural features and well -articulated structures on a site. The purpose of the proposed regulations is to ensure that stormwater facilities are better integrated into site development and further, that they enhance development through thoughtful design. This could include landscaping, rocks, or surface treatments to concrete structures. Historically, best practice has guided the types of plantings that can be included in stormwater areas, but codified standards will provide more clarity for developers and their design teams. Based on input from Planning Commission, the requirement for upgraded concrete structures is only applicable when visible from a public street or public space. Proposed Regulations — Site Grading and Retaining Walls Because site grading and retaining walls are interrelated, it is proposed they be addressed together. The purpose of the new regulations is to require grading and wall designs that respect existing topography and surrounding properties. The design standards for retaining walls respond to several recent developments where tall retaining walls have been installed immediately adjacent to sidewalks and have created uncomfortable pedestrian environments. The proposed ordinance requires that in public spaces, walls and elevation changes be scaled to the pedestrian by using terracing, landscaping, and material changes. For visual and maintenance reasons, steep slopes are explicitly not permitted. In the spirit of promoting more context -sensitive designs, grading plans must consider the impact to current and future development and rights-of-way. In response to Planning Commission's recommendation, the ordinance includes a provision restricting turf grass on slopes steeper than 4:1 which, among other things, is difficult to establish and maintain. Applicability These new design standards would apply to new site development in all zone districts, to expansions of stormwater facilities or retaining walls of 15% or more, and to substantial Council Action Form — Site Design Amendments March 27, 2017 Page 3 modifications of stormwater facilities, walls, or site grading. It is proposed the ordinance be located in Article V of the zoning code, which addresses design standards such as landscape, parking and lighting. If the ordinance is approved, the provisions will also be included in the Architectural and Site Design Manual (ASDM), which supplements the zoning code. This document includes photographs and descriptive captions that will help to communicate the standards. Attachment 2 is an excerpt from the ASDM for reference purposes. RECOMMENDATIONS: Staff recommends approval of the ordinance. RECOMMENDED MOTION: "I move to approve Council Bill No. 06-2017, an ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities, on first reading, order it published, public hearing set for Monday, April 10, 2017 at 7:00 p.m. in City Council Chambers, and that it take effect 15 days after final publication." Or, "I move to postpone indefinitely the ordinance amending Chapter 26 of the Wheat Ridge Code of Laws concerning the regulation of site design standards for site grading, retaining walls and stormwater facilities, for the following reason(s) " REPORT PREPARED BY: Lauren Mikulak, Senior Planner Kenneth Johnstone, Community Development Director Patrick Goff, City Manager ATTACHMENTS: 1. Council Bill No. 06-2017 2. Excerpt from the Architectural and Site Design Manual CITY OF WHEAT RIDGE, COLORADO INTRODUCED BY COUNCIL MEMBER COUNCIL BILL NO. ORDINANCE NO. Series 2017 TITLE: AN ORDINANCE AMENDING CHAPTER 26 OF THE WHEAT RIDGE CODE OF LAWS CONCERNING THE REGULATION OF SITE DESIGN STANDARDS FOR SITE GRADING, RETAINING WALLS AND STORMWATER FACILITIES WHEREAS, the City of Wheat Ridge is a home rule municipality operating under a charter adopted pursuant to Article XX of the Colorado Constitution and vested with the authority by that article and the Colorado Revised Statutes to adopt ordinances for the regulation of land use and protection of the public health, safety and welfare; and WHEREAS, in exercise of that authority, the City Council of the City of Wheat Ridge has previously enacted Chapter 26 of the Wheat Ridge Code of Laws pertaining to zoning, land use, and development; and WHEREAS, Chapter 26 includes regulations to ensure that site grading, retaining walls, and stormwater facilities comply with all technical requirements; and WHEREAS, the City Council recognizes the need for elevating certain site design standards related to site grading, retaining walls, and stormwater facilities; and WHEREAS, the City Council finds that elevating these standards will improve the quality of development projects throughout the City. NOW THEREFORE BE IT ORDAINED BY THE CITY COUNCIL OF THE CITY OF WHEAT RIDGE, COLORADO: Section 1. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-507, to read in its entirety as follows: SEC. 26-507. STORMWATER FACILITIES. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT STORMWATER FACILITIES ARE INTEGRATED INTO SITE DEVELOPMENT AND ARE DESIGNED TO ENHANCE THE DEVELOPMENT THROUGH THE USE OF INNOVATIVE OR LOW IMPACT DESIGN APPROACHES AND THROUGH THE USE OF MATERIALS AND LANDSCAPING THAT COMPLEMENT THE SURROUNDINGS. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS; Attachment 1 2. SUBSTANTIAL MODIFICATION OF EXISTING STORMWATER FACILITIES OR EXPANSION OF SUCH FACILITIES BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. ALL STORMWATER FACILITIES SHALL BE DESIGNED AND MAINTAINED IN ACCORDANCE WITH THE CITY'S CURRENT SITE DRAINAGE REQUIREMENTS. 2. BELOW THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION, PLANT MATERIAL SHALL BE LIMITED TO WETLAND PLANTINGS, GRASSES, OR OTHER GROUNDCOVERS THAT ENHANCE WATER QUALITY AND ARE APPROPRIATE BASED ON PERIODIC FLOODING AND FACILITY MAINTENANCE NEEDS. TREES AND SHRUBS MAY BE PLANTED ABOVE THE FIVE (5) YEAR STORMWATER SURFACE ELEVATION. 3. FOR CONCRETE STRUCTURES OR BASINS THAT ARE VISIBLE FROM A PUBLIC STREET OR PUBLIC SPACE, ROCKS, LANDSCAPING, AND/OR DECORATIVE CONCRETE SURFACE TREATMENTS SHALL BE UTILIZED TO SOFTEN THEIR APPEARANCE. 4. THE SIDE SLOPES OF STORMWATER FACILITIES SHOULD BE GRADUAL, AND GENERALLY LIMITED TO 4:1 OR LESS. 5. THE TOP EDGE OF SLOPES AND EMBANKMENTS SHOULD BE LANDSCAPED WITH GROUPINGS OF TREES AND SHRUBS. THIS SHALL NOT BE CONSTRUED TO MEAN TREES SPACED ON CENTER. PLANTINGS SHOULD BE LOCATED TO ALLOW MAINTENANCE ACCESS AS NEEDED. Section 2. Article V. - Design Standards of Chapter 26 of the Code is amended by the addition of a new subsection 26-508, to read in its entirety as follows: SEC. 26-508. SITE GRADING AND RETAINING WALLS. A. PURPOSE. THE PURPOSE OF THESE REGULATIONS IS TO ENSURE THAT GRADING DESIGNS RESPECT EXISTING TOPOGRAPHY AND ARE SENSITIVE TO EXISTING LANDFORMS AND THE SURROUNDING PROPERTIES. B. APPLICABILITY. THE STANDARDS AND REQUIREMENTS OF THIS SECTION SHALL APPLY TO: 1. SITE DEVELOPMENT IN ALL ZONE DISTRICTS. 2. SUBSTANTIAL MODIFICATION OF EXISTING RETAINING WALLS OR SITE GRADING OR EXPANSION SUCH WALLS BY MORE THAN FIFTEEN (15) PERCENT. C. DESIGN. 1. WALLS AND ELEVATION CHANGES THAT ARE ADJACENT TO PUBLIC SPACES SHALL BE DESIGNED TO PROVIDE A PEDESTRIAN SCALED ENVIRONMENT THROUGH THE USE OF TERRACING, LANDSCAPING, AND/OR MATERIAL VARIATION. 2. ALL RETAINING WALLS SHALL BE BUILT PER THE REQUIREMENTS OF ANY APPLICABLE CODES, INCLUDING BUT NOT LIMITED TO THE TECHNICAL Attachment 1 CODES ADOPTED BY THE CITY AND CONTAINTED IN CHAPTER 5 OF THIS CODE. 3. LANDSCAPING SHALL BE PROVIDED IN COMBINATION WITH RETAINING WALLS TO SOFTEN THE APPEARANCE OF WALLS. 4. ALL TERRACED PLANTING AREAS BETWEEN WALLS SHALL BE OF SUFFICIENT WIDTH TO SUPPORT VEGETATION AND ROOT SYSTEMS. 5. SITE GRADING SHALL NOT ADVERSELY IMPACT ADJACENT PROPERTY AND/OR RIGHTS-OF-WAY. GRADING SHALL ANTICIPATE FUTURE DEVELOPMENT AND SHALL INTEGRATE WITH ADJACENT PROPERTY AND/OR RIGHT-OF-WAY. 6. SLOPES STEEPER THAN 3:1 ARE NOT PERMITTED. GRADES OF 4:1 OR LESS ARE ENCOURAGED. 7. TRANSITION GRADES SHOULD BE ROLLING AND NATURAL RATHER THAN ONE CONTINUOUS STRAIGHT LINE. 8. TURF GRASS SHOULD NOT BE USED ON SLOPES STEEPER THAN 4:1. Section 3. Section 26-1110 of the Code, concerning site design requirements in the mixed use zone districts, is hereby amended by the addition of two (2) new subsections, J and K, to read in their entirety as follows: J. THE REQUIREMENTS OF SECTION 26-507 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. K. THE REQUIREMENTS OF SECTION 26-508 SHALL APPLY IN ALL MIXED USE ZONE DISTRICTS. Section 4. Severability, Conflicting Ordinances Repealed. If any section, subsection or clause of this Ordinance shall be deemed to be unconstitutional or otherwise invalid, the validity of the remaining sections, subsections and clauses shall not be affected thereby. All other ordinances or parts of ordinances in conflict with the provisions of this Ordinance are hereby repealed. Section 5. Effective Date. This ordinance shall take effect fifteen (15) days after final publication, as provided by Section 5.11 of the Charter. INTRODUCED, READ, AND ADOPTED on first reading by a vote of to this _th day of , 2017 and ordered published in full in a newspaper of general circulation in the City of Wheat Ridge, and Public Hearing and consideration on final passage set for , 2017 at 7:00 p.m., in the Council Chambers, 7500 West 29th Avenue, Wheat Ridge, Colorado. READ ADOPTED AND ORDERED PUBLISHED on second and final reading by a vote of to , this day of , 2017. SIGNED by the Mayor on this day of , 2017. Joyce Jay, Mayor Attachment 1 ATTEST: Janelle Shaver, City Clerk Approved as to Form Gerald E. Dahl, City Attorney First Publication: Second Publication: Wheat Ridge Transcript Effective Date: Published: Wheat Ridge Transcript and www.ci.wheatridge.co.us Attachment 1 3.9 Stormwater Facilities Design Principle: Stormwater facilities should be integrated into site development and be designed to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. Design Standards: 1. All Stormwater facilities shall be designed and maintained in accordance with the City's current Site Drainage Requirements. 2. Below the 5 -year stormwater surface elevation, plant material is limited to wetland plantings, grasses, or other groundcovers that enhance water quality and are appropriate based on periodic flooding and facility maintenance needs. Trees and shrubs may be planted above the 5 -year stormwater surface elevation. 3. For concrete structures or basins that are visible from a public street or public space, rocks, landscaping, and/or decorative concrete surface treatments shall be utilized to soften their appearance. Design Guidelines: 4. The side slopes of stormwater facilities should be gradual, and generally limited to 4:1 or less. 5. The top edge of slopes and embankments should be landscaped with groupings of trees and shrubs. Plantings should be located to allow maintenance access as needed. Chapter 3 - Site Design Stormwater Facilities. Rocks and wetland plantings make this drainage channel a visual amenity that complements the area. Stormwater Facilities. Trees, wetland plantings, and stone walls (natural or stamped) soften stormwater facilities that are visible from a public street. Attachment 2 Wheat Ridge Architectural and Site Design Manual 17 Site Grading and Retaining Walls. A pedestrian scaled environment shall be provided when walls and elevation changes are next to public space. Site Grading and Retaining Walls. Large grade changes can be accommodated in an attractive manner through the use of terraces and landscaping. Rollin! \ StoPe stroi9 et\ Sol Op 1_ Site Grading and Retaining Walls. Transition grades should be rolling rather than one continuous straight line. 3.10 Site Grading and Retaining Walls Design Principle: Grading designs should respect the existing topography and be sensitive to existing landforms and surrounding properties. Design Standards: 1. Walls and elevation changes that are adjacent to public spaces shall be designed to provide a pedestrian scaled environment through the use of terracing, landscaping, and/or material variation. 2. All retaining walls shall be built per the requirements of the applicable building codes. 3. Landscaping shall be provided in combination with retaining walls to soften their appearance. 4. All terraced planting areas between walls shall be of sufficient width to support vegetation and root systems. 5. Site grading shall not adversely impact adjacent property and/ or right-of-way, and shall anticipate future development and integration of adjacent property and/or right-of-way. 6. Grades of 4:1 or less are encouraged, slopes steeper than 3:1 are not permitted. Design Guidelines: 7. Transition grades should be rolling and natural rather than one continuous straight line. 8. Turf grass should not be used on slopes steeper than 4:1. 18 Wheat Ridge Architectural and Site Design Manual Kenneth Johnstone From: Kenneth Johnstone Sent: Tuesday, March 28, 2017 7:50 AM To: Kenneth Johnstone Subject: City Council - Gen, Kristi and George absent City Council - Gen, Kristi and George absent - Arbor Day - Dorothy Archer, 3640 Marshall, R-1 code and heights allowable - Colin, Perlmutter's office, making housing affordable conference ER Moratorium, - ordinance 1616 - Hoppe introduction - Carol Salzmann, raised consumer protection issues, proposed 12 month moratorium, status of house and senate bills, state moratorium to send department of health, 72000 patients a year, - Hoppe motion, Zach amendment to 12 months, Larry 2nd on amendment - 5-0 - Main motion - 5-0 Small scale alcohol production, Larry motion, Monica 2nd, 5-0 Design Standards, Monica motion, Hoppe 2nd, 4-1, Urban "no" Sent from my Wad City of W heaLF dge COMMUNITY DEVELOENT Sec. 26-507. — Stormwater Facilities A. Principle. Stormwater facilities should be integrated into development and be design d in a manner to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. B. Applicability. 1. Site development p 2. Modification or expansion of existing stormwater facilities by more than 15% C. Design. - f J s C-� 1. Design and maintain all stormwater facilities in accordance with they of _ite Drainage Requirements. 2. The top edge of slopes and embankments should be landscaped with groupings of naturalized trees and shrubs. Plantings should be seek to allow maintenance access where needed. ( - "f e-*- 3. Trees and shrubss giay be planted above the 5 -year stonnwater surface elevation. Below the 5 -year„ surface elevation; plant material is limited to turf or other groundcovers. The bottoms of detention ponds may be planted with a mixture of grasses or other plants that are suited to periodic flooding and that se e oance water quality. 4. Structures fo eiks shall be aesthetically leasing and natural in form where visible from a public street or public space. Roc s and/or landscaping should be utilized to soften the appearance of concrete structures. 5. Side slopes of til t should be gradual (4:1 or less). Sec. 26-508. — Site Grading and Retaining Walls A. Principle. Respect the existing topography with grading designs that are sensitive to existing landforms and the surrounding neighborhood. B. Applicability. 1. Site development 2. Modification of existing walls or grading plans by more than 15% C. Design. 1. Walls and elevation changes adjacent to public spaces shall be designed to maintain a pedestrian friendly streetscape. 2. All retaining walls over 48" in height must be designed by a licensed n 1 (lt 0-C engineer. 3. Individual walls taller than 48" (5 feet?) are not permitted in public areas ••• or within X feet of public right-of-way. 4. In developing sites, slopes less than 4:1 are encouraged; slopes than 3:1 are not permitted. =-e 5. Transition grades should be rolling rather than one continuous straight line. 6. Site grading designs shall not adversely impact adjacent property and/or public right-of-way. 7. Provide landscaping in combination with retaining walls to soften theiska�l�/, appearance.' ' 8. Planting areas on terraces between walls shall be of sufficient width to support vegetation and root systems. 9. , site grading shall anticipate future development and integration of adjacent property and/or public right-of-way, 2 I City Of KWh6atROge MUNITY DEVELOPMENT City of Wheat Ridge Municipal Building 7500 W. 29'h Ave. Wheat Ridge, CO 80033-8001 P: 303.235.2846 F: 303.235.2857 Stormwater, Site Grading and Retaining Walls Ordinance Planning, Public Works and Forestry September 26, 2016 • Stormwater Facility Provisions o Ensure that all important areas are touched on o Is the trigger to require these provisions appropriate? o City of Wheat Ridge Site Drainiage Requirements: Is this the correct term? Does City Council need to adopt these for us to codify this reference? • Site Grading and Retaining Walls o Ensure that all important areas are touched on o Is the trigger to require these provisions appropriate? o Should we also include a percentage for grade in addition to the ratio? • Next Steps City of Ot l W heat �ge COMMUNITY DEVELOPMENT Sec. 26-507. — Detention Areas A. Principle. Detention areas should be integrated into development and be designed in a manner to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. ? B. Applicability. - 1. Site development — A�"UUDy 2. Modification or expansion of existing detention facilities by more than 15% ? C. Design. 1. The top edge of slopes and embankments should be landscaped with groupings of naturalized trees and shrubs. Plantings should be set back to allow maintenance access where needed. 2. Structures for detention ponds shall be aesthetically pleasing and natural in form where visible from a public street or public space. Rocks and/or landscaping should be utilized to soften the appearance of concrete structures. 3. Side slopes of detention facilities should be gradual (4:1 or less). Sec. 26-508. — Site Grading and Retaining Wa11s A. Principle. Respect the existing topography with grading designs that are sensitive to existing landforms and the surrounding neighborhood. B. Applicability. 1. Site development 2. Modification of existing walls or grading plans by more than 15% ! C. Design. 1. Walls and elevation changes adjacent to public spaces shall be designed to maintain a pedestrian friendly streetscape. 2. In developing sites, slopes less than 4:1 are encouraged; slopes greater than 3:1 are not permitted. 3. Transition grades should be rolling rather than one continuous straight line. 4. Site grading designs shall not adversely impact adjacent property. 5. Provide landscaping in combination with retaining walls to soften their appearance. 6. Planting areas on terraces between walls shall be of sufficient width to support vegetation and root systems. 7. Where appropriate, site grading shall anticipate future development and integration of adjacent property. Proposed additions to ASDM A part of Chapter 3, Site Design, these provisions would apply to projects with new buildings or major additions in all overlay districts and for all building types (Commercial/Retail/Mixed-Use, Heavy Commercial/Industrial, and Multifamily) 3.09 Detention Areas Design Principle: Detention areas should be integrated into development and be designed in a manner to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. Design Standards: 4. The top edge of slopes and embankments shall be landscaped with groupings of naturalized trees and shrubs. Plantings should be set back to allow maintenance access where needed. 5. Structures for detention ponds shall be aesthetically pleasing and natural in form where visible from a public street or public space. Rocks and/or landscaping should be utilized to soften the appearance of concrete structures. 6. Side slopes of detention facilities should be gradual (4:1 or less). 3.10 Site Grading and Retaining Walls Design Principle: Respect the existing topography with grading designs that are sensitive to existing landforms and the surrounding neighborhood. Design Standards: 8. Walls and elevation changes adjacent to public areas shall be designed to maintain a pedestrian friendly streetscape. 9. In developing sites, slopes less than 4:1 are encouraged; slopes greater than 3:1 are not permitted. 10. Transition grades should be rolling rather than one continuous straight line. 11. Site grading designs shall not adversely impact adjacent property. 12. Provide landscaping in combination with retaining walls to soften their appearance. 13. Planting areas on terraces between walls shall be of sufficient width to support vegetation and root systems. Design Guidelines: 14. Where appropriate, site grading shall anticipate future development and integration of adjacent property. 15. A combination of low walls and gradual slope changes or low staggered walls instead of one high (taller than six feet) is encouraged where possible. 16. Retaining walls should be constructed of materials that are compatible with the main building architecture. 2 City of 1�cormMUNITY DEVELOI'MENI� Article 11, Mixed Use Districts: Section 26-1110. Open Space Requirements o Restricts that land with a slope steeper than 3:1 shall not be considered usable open space o Allows drainage ways, ponds, and other areas required for stormwater quality or detention to qualify as usable open space if such areas are designed for passive or active use and are landscaped with grass, shrubs, and/or trees. o Exempts Mixed Use Districts from Section 26-502 (Landscaping requirements) Article 4, Subdivision: Section 26-411. Subdivision design o Stormwater, drainage and floodplains ■ Requires that drainage, wetland, and floodplain areas shall be preserved in their natural state. No encroachments shall be made on existing channels to preserve the natural and beneficial functions, but where they are encroached upon, acceptable mitigation shall be provided. ■ Requires that any subdivision must allow continued historic flow of waters, and provide drainage easements and stormwater facilities for proposed and actual on- and off-site runoff. o Slope ■ Restricts steep land (10% slope or greater), unstable land and areas, and areas having inadequate drainage from being subdivided unless acceptable provisions are made by a registered engineer. These areas may be included as part of a lot or lots where there are appropriate building areas elsewhere. Section 26-412. Street design o Grade and topography. ■ Requires that streets be designed to bear a reasonable relationship to the topography of the land to the maximum extent feasible ■ Restricts that the maximum grade by street classification shall not be exceeded; maximum grade is determined by the public works department. Article 5, Landscaping: Section 26-502. Landscaping requirements o The definition of landscaping includes, in addition to living plant materials, natural features such as rock, stone, bark and structural features including, but not limited to, fountains, reflecting pools, art work, screen walls, fences and benches. Article 6, Supplementary Regulations Section 26-603. Fences, walls and obstructions to view o Divisional fences and divisional walls are permitted in any zone district ■ Divisional fences and walls allowed up to 6 feet tall, and subject to sight distance triangle requirements. Proposed additions to ASDM A part of Chapter 3, Site Design, these provisions would apply to projects with new buildings or major additions in all overlay districts and for all building types (Commercial/Retail/Mixed-Use, Heavy Commercial/Industrial, and Multifamily) 3.09 Detention Areas Design Principle: Detention areas should be integrated into development and be designed in a manner to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative or low impact development approaches. Design Standards: 1. The top edge of slopes and embankments should be landscaped with groupings of naturalized trees and shrubs. Plantings should be set back to allow maintenance access where needed. 2. Structures for detention ponds shall be aesthetically pleasing and natural in form where visible from a public street or adjacent residential development. Rocks and/or landscaping should be utilized to soften the appearance of concrete structures. 3. Side slopes of detention facilities should be gradual (4:1 or less). 3.10 Site Grading and Retaining Walls Design Principle: Respect the existing topography with grading designs that are sensitive to existing landforms and the surrounding neighborhood. Design Standards: 1. Walls and elevation changes adjacent to public areas shall be designed to maintain a pedestrian friendly streetscape. 2. In developing sites, slopes less than 4:1 are encouraged; slopes greater than 3:1 are not permitted. 3. Transition grades should be rolling rather than one continuous straight line. 4. Site grading designs shall not adversely impact adjacent property. 5. Provide landscaping in combination with retaining walls to soften their appearance. 6. Planting areas on terraces between walls shall be of sufficient width to support vegetation and root systems. Design Guidelines: 7. Where appropriate, site grading shall anticipate future development and integration of adjacent property. FA 8. A combination of low walls and gradual slope changes or low staggered walls instead of one high (taller than six feet) is encouraged where possible. 9. Retaining walls should be constructed of materials that are compatible with the main building architecture. 3 ` -(,Or. W heat id e COMMUNITY DEVELOPMENT Walls with landscaping and columns -�. .�ti •may �' '�''� ?-7 Permeable pavers in a parking area 4 Dl 3n0WC-1 Retaining wall with landscaping to soften to soften ,'.• � � '9 t ^�Q.''e 1:Yy[[ u ■O Yf .v tG lif i�.L .aau -•eeaM/ u+ vs 71�e M 6 City of Wheat Ridge COMMUNITY DEVELOPMENT 3.9 Fence and Wall Design Design Principle: Fences, walls and other screening help define private open space and also enhance the adjacent streetscape. Their design shall utilize highu ' terials and complement the surrounding landscape. Fences, walls, and v 3 adjacent to public areas should be designed to maintain a pedestrian friendly streetscape. Design Standards: �� SV `� 1. Acceptable materials for galls are modular concrete units, rockeries, or cast - in -place concrete faced with brick or stone or with a decorative finish. 2. Long expanses of fences or walls should be broken up into smaller segments with periodic columns, insets or change in materials. 3. Provide landscaping in combination with walls and fences to soften their appearance. 4. Planting areas on terraces between walls should be of sufficient width to support vegetation and root systems. "'kCLDesign Guidelines: 4,.e1WA MAI 5. A combination of low walls and gradual slope changes or low staggered walls instead of one high wall (taller than six feet) is encouraged where possible. 6. To the greatest degree possible, development shall respect the existing topography of the site and avoid usage of retaining walls. 7. Fencing and walls should be constructed of materials that are compatible with the adjacent building architecture. 3.10 Detention Areas �v� Design Principle: Detention areas should be integrated into development and be designed in a manner to enhance the development through the use of materials and landscaping that complement the surroundings, or through innovative designs. Design Standards: 1. The top edge of slopes and embankments should be landscaped with groupings of naturalized trees and shrubs. Plantings should be set back to allow maintenance access where needed. 2. Structures for detention ponds shall be aesthetically pleasing and natural in form where visible from a public street or adjacent residential development. Rocks and/or landscaping should be utilized to soften the appearance of concretee structures. 3. Side slopes of detention facilities should be gradual (less than 4:1) to allow for more usable open space. 4. Landscape detention areas so they can serve as usable open space. Design Guidelines: 5. Concrete pans at the low point of detention swales are discouraged. 6. Retaining walls in detention ponds are discouraged. 3.11 Site Grading and Drainage Design Principle: Preserve the natural setting with grading designs that are sensitive to existing landforms and the surrounding neighborhood. Design Standards: 1. In developing sites, limit slopes to 4:1 or less to the greatest extent possible. 2. Transition grades between old and new elevations should be rolling rather than one continuous straight line. 3. Site grading designs should avoid drainage impacts (such as erosion and road damage) both on-site and downstream. 4. Avoid grade changes within the drip -line of existing trees that are to be maintained. Design Guidelines: 5. The design of site improvements shall respect the existing topography of the site and minimize cut -and -fill to preserve the natural terrain to the greatest extent possible. 2 NSA ASA,J 6.4 LOW IMPACT DEVELOPMENT Low Impact Development (LID) is a comprehensive approach that combines land/development planning with engineering design to manage stormAvater. The goal is to replicate the pre -development hydrologic regime for a given site. This is accomplished by planning for management of stormwater fiom the very beginning rather than retrofitting stormwater facilities onto a development plan. Key components of Low Impact Development practices are: 1. Integration of a development into the site with consideration toward preservation of the site's natural features, including drainageways, open space. wetlands and areas where infiltration potential is high. 2. Site drainage design that addresses management of stonnwater at the source. with controls distributed throughout the site in small elements. While this practice doesn't necessarily eliminate the need for a centralized facility such as a stormwater detention pond. it can reduce the volume (and space) required for such a facility. 3. Reduction of impervious surfaces through the use of grass sivales. porous pavement. green roofs. downspout planters, vegetated buffer areas. rain gardens and other measures. 6-2 4. A focus on volume reduction as opposed to peak flow reduction as the primary hydrologic objective. This is in keeping with the LID philosophy of striving to achieve a post -development hydrologic regime that is closer to the duration and frequencies of the natural, pre -development regime. Runoff management practices that are suited to Low Impact Development (LID) include: • Filter/buffer strips and other multifunctional landscape areas • Rain gardens • Grassed swales and bioretention swales • Pervious pavements The City of Louisville encourages the design and implementation of Low Impact Development design techniques for all new development and redevelopment. LID techniques that employ infiltration are well-suited to the Type B soils that predominate within the City. Volume 3 of the USDCM, Chapter 1, presents design guidelines and criteria for LID techniques to assist site planners and engineers with application of LID to new development or redevelopment within the City of Louisville. 6-3