The purpose of this chapter is to categorize hillsides into five slope categories and establish limits on land use density. Additional design standards and guidelines are provided in article VII (Design Standards and Guidelines). The development and density limits established in this chapter apply based on the location of property with five established slope zones (section
17.52.020).
(Ord. No. 1000 § 4, 2022)
All property within the city can be categorized into one of
the following slope zones. Regulations apply as indicated.
A. Zone
1 (five percent natural slope or less). This is not a hillside condition.
Grading with conventional fully padded lots and terracing is acceptable.
B. Slope
Zone 2 (five percent to 7.99 percent slope). Development with grading
is permitted in this zone, but existing landforms must retain their
natural character. Padded building sites are permitted; however, techniques
such as contour grading, combined slopes, limited cut and fill, and
split-level architectural prototypes, or padding for the structures
only, may be required to reduce grading.
C. Slope
Zone 3 (eight percent to 14.9 percent slope). This is a hillside condition.
Special hillside architectural and design techniques (see article
VII (Design Standards and Guidelines)) that minimize grading are required
in this zone. Architectural prototypes are expected to conform to
the natural landform by using techniques such as split-level foundations
of greater than 18 inches, stem walls, stacking, and clustering.
D. Slope
Zone 4 (15 percent to 29.9 percent). Development within this zone
is limited to no more than the less visually prominent slopes and
then only where it can be shown that safety, environmental, and aesthetic
impacts can be minimized. The use of larger lots, variable setbacks,
and variable building structural techniques such as stepped or pole
foundations are expected. Structures shall blend with the natural
environment through their shape, materials, and colors. Impact of
traffic and roadways is to be minimized by following natural contours
or using grade separations.
E. Slope
Zone 5 (30 percent and over). This is an excessive slope condition
and development is prohibited, unless all the following are satisfied:
1. The
property is located south of Banyan Street;
2. At
least 75 percent of the lots or parcels that are the subject of the
development application are surrounded by lots or parcels improved
with structures;
3. The
proposed project is determined to appropriately address slope stability
and other geological factors of the site; and
4. Vegetation
fuel management for wildfire protection can be achieved and maintained.
(Ord. No. 1000 § 4, 2022)
This section correlates the steepness of the terrain with limitations
on development intensity. The total allowable residential dwelling
units shall be calculated based on the total (buildable) land area
within each slope category multiplied by the capacity factor for each
to the slope category.
A. Using
the land capacity schedule. Table 17.52.030-1 (Land Capacity Calculation)
converts the amount of gross site acres into the amount of net buildable
acres based on slope measurement.
TABLE 17.52.030-1 LAND CAPACITY CALCULATION
|
---|
Land capacity formula: (Acreage of _% slope) x (Capacity ratio)
= Net buildable area
|
---|
Slope Measurement
|
Acres of Land (Gross)
|
Capacity Ratio (x)
|
Adjusted Net Buildable Area (Acres × Capacity Ratio)
|
---|
Under 10%
|
A
|
1.000
|
Ax
|
10-14.9%
|
B
|
0.750
|
Bx
|
15-19.9%
|
C
|
0.500
|
Cx
|
20-24.9%
|
D
|
0.250
|
Dx
|
25-29.9%
|
E
|
0.025
|
Ex
|
+30%
|
F
|
0.000
|
Fx
|
|
|
Total
|
(Ax + Bx + Cx + Dx + Ex + Fx)
|
B. Calculating
permitted units. The maximum number of dwelling units that may be
permitted in a proposed development shall be determined by multiplying
the total adjusted net buildable area (Ax + Bx + Cx + Dx + Ex + Fx)
above by the permitted number of allowed units per acre according
to the zone.
C. Exceptions.
The following land areas, meeting any or all of the following criteria,
shall not be included in the calculation of total allowable dwelling
units:
1. All
land areas, regardless of slope, which will be subject to inundation
during a 100-year storm after development has occurred.
2. All
land which is in a geologic hazard zone, as defined in the public
health and safety chapter of the general plan of the city, and for
which no feasible mitigation measures are proposed.
3. All
land area which lies within a federally recognized blue line stream
or contains significant riparian or streambed environs.
4. All
the following are satisfied:
a. The property is located south of Banyan Street;
b. At least 75 percent of the lots or parcels that are the subject of
the development application are surrounded by lots or parcels improved
with structures;
c. The proposed project is determined to appropriately address slope
stability and other geological factors of the site; and
d. Vegetation fuel management for wildfire protection can be achieved
and maintained.
(Ord. No. 1000 § 4, 2022)