Chapter 15.07 — STANDARDS FOR HILLSIDE SUBDIVISIONS

The goals and policies of the San Rafael general plan and adopted specific plans and neighborhood plans, seek to protect public health and safety by minimizing hazards, including seismic and landslide risks, soil erosion, and fire danger associated with development on steep and/or unstable slopes. Additionally, plan policies encourage preservation of natural hillside features and the development of hillside site design standards. The standards for the design of subdivisions on slopes over twenty-five percent (25%) are intended to implement these objectives by requiring that lots in hillside subdivisions realistically relate to the natural topography of the land by limiting grading and retaining much of the natural terrain. The standards also implement plan policies by relating density to site constraints and to city design policies. Additionally, in the case of substandard streets, these provisions seek to assure adequate emergency access by providing additional on-site parking.

(Ord. 1787 § 1 (part), 2002).

(a)

General. The standards listed below shall be utilized to evaluate the lot configuration of all applications proposed in hillside areas where slopes are over twenty-five percent (25%). In addition to the Zoning Ordinance requirements in effective in the area, any lot created after 1989 (Ordinance No. 1561) shall meet the density criteria and contain at least the minimum lot width and area, as related to the applicable San Rafael general plan land use plan designation and its natural topographical slope as set forth in the following tables. Lower densities and larger lot sizes may be required where potentially hazardous conditions or special natural features occur or, where development would be highly visible to the neighborhood or community. In no instance can the density exceed that allowed by the zoning district.

Subsections (a)—(d) shall not apply to SB 9 Housing Developments (regulated by Section 14.15.282) or urban lot splits (regulated by Chapter 15.155—Urban Lot Splits).

Table 15.07.020A

HILLSIDE RESOURCE RESIDENTIAL LAND USE DESIGNATION

• (0.1-0.5 units per gross acre)

Table 15.07.020B

HILLSIDE RESIDENTIAL LAND USE DESIGNATION

• (0.5-2.0 units per gross acre)

Table 15.07.020C

LOW DENSITY LAND USE DESIGNATION

(2-6.5 units per gross acre)

(b)

Calculation of Average Slope. For the purpose of this chapter, average slope shall be calculated before grading using the following formula:

S = .00229IL

A

where .00229 is the conversion factor for square feet; "S" is the average percent of slope; "I" is the contour interval in feet; "L" is the summation of length of the contour lines in scale feet; and "A" is the area of the parcel in acres.

For parcels over five (5) acres in size, the subdivider has the option of calculating the amount and location of land falling into each slope category. At the time of application filing, the subdivider shall submit a base topographical map of the subject site that has been prepared and signed by a registered civil engineer or licensed land surveyor. The topographic map shall have a scale of not less than one inch (1″) equal to two hundred feet (200') and a contour interval of not more than five feet (5') provided that the contour interval may be ten feet (10') when the slope is more than twenty percent (20%). A uniform contour interval shall be used on all maps. This base topographical map shall include all adjoining properties within one hundred fifty feet (150') of the site boundaries. Slope bands in the range of zero to ten percent (0-10%), twenty to thirty percent (20-30%), thirty to forty percent (30-40%) and forty percent (40%) or greater shall include, or be accompanied by, a tabulation of the land area in each slope category specified in acres. The exact method for computing the percent slope and area by percent slope category should be sufficiently described and presented so that a review can readily be made.

(c)

Development and lot clustering. For clustered developments or where it can be demonstrated that adequate access exists, a lot with lesser width and area than required by the percent of slope specified in this chapter may be allowed where it furthers the goals of the hillside resource residential design guidelines manual and reduces project impacts, provided that the overall project density is consistent with the slope tables. No lot shall be less than the minimum required by the Zoning Ordinance.

(d)

Environmental and Design Review Permit requirement. Any lot in a major or minor subdivision created for the purpose of development, where the percent of slope is over twenty-five percent (25%) shall require a major environmental and design review permit, processed consistent with the provisions of Title 14 (Zoning) of the municipal code. This permit application shall be reviewed by the planning commission to assure that such lots and the subdivision design comply with the following general plan criteria as implemented through the hillside resource residential design guidelines manual:

(1)

Subdivision grading minimized;

(2)

Avoids highly visible hillsides and ridgeline development;

(3)

Preserves hillsides as visual backdrop;

(4)

Steep slopes avoided;

(5)

Clustering of development to be utilized to minimize visual impacts;

(6)

Tree preservation maximized;

(7)

Minimizes removal of natural vegetation;

(8)

More hazardous/unstable portions of site avoided;

(9)

Mitigates geotechnical site constraints or conditions when needed;

(10)

Buildings achieve hillside design quality; and

(11)

Preserves or protects unique or special natural features of the site, such as rock outcroppings, mature vegetation, landforms, creeks, drainage courses, hilltops or ridgelines.

(e)

The following reports and maps shall be prepared prior to tentative map approval in order to insure that the subdivision design is consistent with the San Rafael general plan:

(1)

A geotechnical investigation prepared consistent with the geotechnical review matrix shall be conducted.

(2)

A drainage report prepared in accordance with the requirements outlined in the hillside resource residential design guidelines manual.

(3)

A biological survey, which classifies portions of the site by their degree of risk of plant communities from wildland fires and establishes guidelines for development in riparian and watershed areas.

(4)

An arborist/forester's report consistent with the requirements outlined in the hillside resource residential design guidelines manual shall be prepared which establishes guidelines for the preservation of significant trees.

(5)

A grading and erosion control plan consistent with the requirements outlined in the hillside resource residential design guidelines manual shall be prepared.

(6)

A building envelope shall be established for each lot consistent with the hillside resource residential design guidelines manual.

(Ord 1787 § 1 (part), 2002; Ord. No. 2013, § 4, 8-1-2022; Ord. No. 2039, § 4(Exh. C), 7-15-2024)

15.07.030 - Street, driveway and parking standards.

(a)

Narrower street widths (acceptable to the city engineer and other city departments) can be approved when it will reduce grading impacts and the number of lots, topography, and the level of future traffic development justifies the reduction. Twenty-five feet (25') is the minimum width requirement for a public street.

(b)

Each lot shall have a private driveway, the grade of which shall not exceed eighteen percent (18%), with adequate provision for ingress and egress. With a supportive recommendation from city departments, an

exception may be granted to allow grooved driveways with a grade of eighteen to twenty-five percent (1825%), when it will result in a project which has fewer impacts on grading, trees and views.

(c)

Each lot created on substandard city streets and all private streets shall provide a minimum of two (2) offstreet, independently accessible guest parking places for each dwelling unit intended to be developed on the lot. These parking spaces shall not be located on the driveway apron. These spaces shall be conveniently placed relative to the dwelling unit they serve. This requirement may be waived or reduced when the size or shape of the lot or the need for excessive grading make the requirement infeasible. Subsection (c) shall not apply to SB 9 Housing Developments (regulated by Section 14.15.282) or urban lot splits (regulated by Chapter 15.155—Urban Lot Splits).

(d)

No private street leading to a private driveway on a lot shall exceed a grade of eighteen percent (18%). (Ord. 1787 § 1 (part), 2002; Ord. No. 2013, § 4, 8-1-2022; Ord. No. 2039, § 4(Exh. C), 7-15-2024) Chapter 15.08 - DEDICATIONS AND RESERVATIONS