The implementation of the Hillside Grading Guidelines is essential to affect continued quality community development. The City of Canyon Lake desires to encourage planning, engineering, and development that results in minimal site grading in addressing the varying terrain and highly visible hillside areas. This can be accomplished by following the natural contours as much as possible. From large scale subdivision design to individual lot grading plans, graded slopes should be rounded and contoured to blend with the existing terrain. Significant natural vegetation should be retained and incorporated into projects whenever possible.
The guidelines shall apply unless specifically modified by the approving authority and findings are made that the modification is consistent with the findings listed in Subsection (k) hereof.
(a) Grading must minimize the disturbance to the natural landform, not destroy visual quality and community character, nor create conditions that may result in landslides, flooding, or erosion.
(b) No grading shall take place in known or suspected hazardous areas as determined by the City without a geological survey and/or other data and tests as requested by the City.
(c) Projects located in hillside areas shall incorporate clustering, varying setbacks, multiple orientations, and other site planning techniques to preserve open spaces, protect natural features, and offer views to residents.
(d) Transitioning Slopes. Minimal radius rounding at edges of cut and fill slopes is not acceptable. Proper transitioning from manufactured slopes to natural slopes shall be achieved gradually and naturally using radii or irregular curvilinear shapes that will blend into the adjoining topography tangentially and not create abrupt changes.
(e) Good grading design must be exercised for safety as well as aesthetics and should incorporate the following measures:
(1) Utilization of landform or contour measures to produce cut-and-fill slopes compatible with existing land character. Continuous unbroken slope surfaces that are visible from offsite are discouraged. Linear or straight slopes shall not exceed 100-feet in distance before next rounded contoured edge. Edges and exposed tops and toes of slopes shall be rounded with a minimum five-foot radius where there are linear slopes up to 50 feet in length and ten-foot radius where linear slopes are greater than 50 feet. The parallel planes of adjacent linear slopes shall be offset by minimum distance of ten-foot measured perpendicular to the planes.
(2) Grading slopes contoured by varying slope increments and undulating banks vertically and horizontally.
(3) Varied cut-and-fill banks and drainage terrace spacing to alleviate monotony and to allow informal landscaping.
(4) Berms at top of slopes and other locations used to screen, vary profile, and ensure drainage away from slopes.
(5) Varied pad levels to avoid appearance of monotonous slope banks and flat level lots.
(f) Minimal Grading. This is typically used for large lot single-family homes, custom homes with variable foundations that conform to the existing slopes and other uses such as golf courses that utilize the least amount of grading in order to get the facility and structures built, but is also acceptable for commercial uses. This technique embraces the following concepts:
(1) Grading should be limited to individual flat graded pad areas for residential building sites. Grading should be limited to only the required building areas and adjacent outdoor amenities in steep hillside areas.
(2) Foundation systems that require little or no grading are encouraged, forcing the architecture to conform to the land rather than the land to conform to the dwelling.
(3) Roadways, driveways, and individual building pads should be designed to conform with contours and to attempt to daylight in the center of the road or building pad to ensure a minimum cut and fill situation.
(g) All manufactured cut and fill slopes exceeding ten-feet in height which will be either exposed to permanent public view or are adjacent to environmentally sensitive areas, should be designed with features characteristic of natural slopes where physically feasible so that their ultimate appearance will resemble a natural slope. This will include slopes along streets and highways, slopes adjacent to parks, schools, or open spaces and other public facilities and other prominent and visible slopes.
(h) Clustering of development is encouraged within the allowable density identified in the General Plan. This is particularly important in environmentally sensitive areas in order to reduce the potential for fire hazard, erosion and excess runoff, and to preserve existing natural features and open space.
(I) In the planning, design, and development of public utilities and infrastructure, every reasonable effort shall be made to minimize grading impacts and harmonize with natural contours and character of the landform design applied.
(j) The City Council or its designee may modify or waive any of the hillside/grading guidelines when an improved design will result or where it can be demonstrated that imposing hillside grading guidelines would either render a parcel of land unbuildable, create a loss of all its reasonable economic use, or place an undue restriction on the improvement of the property, the City Council may allow development consistent with the General Plan, only when all of the following findings can be made:
(1) The site is physically suitable for the design and siting of the proposed development. The proposed development will result in minimum disturbance of sensitive areas;
(2) The grading proposed in connection with the development will not result in soil erosion, silting of lower slopes, flooding, severe scarring or any other geological instability or fire hazard which would affect health, safety and general welfare as determined by the City Engineer and all other requirements of applicable law and regulation are met;
(3) The proposed development retains the natural character and visual quality of the site and the aesthetic qualities of the area; and
(4) The proposed development is in conformance with the qualitative development standards and guidelines as established in this Chapter and is in conformance with the goals, objectives, and policies of the General Plan.
(Ord. 112, passed 3-4-2009)