Chapter 13.14
RURAL RESIDENTIAL DENSITY DETERMINATIONS

Sections:

13.14.010    Purpose.

13.14.020    Scope.

13.14.025    Amendment.

13.14.030    Definitions.

13.14.040    Application.

13.14.050    Rural residential density determinations.

13.14.060    Matrix calculation.

13.14.070    Overriding minimum acreage maximum density policies.

13.14.080    Resource and constraint data.

13.14.090    Fees.

13.14.010 Purpose.

The purpose of this chapter is to allow for a consistent determination of the development potential of rural land parcels based upon the availability of services, environmental and site-specific constraints, and resource protection factors mandated by Measure J, the growth management system, its implementing ordinances and policies, the County’s General Plan and the Local Coastal Program Land Use Plan. [Ord. 4416 § 13, 1996; Ord. 4406 § 13, 1996; Ord. 3330 § 1, 1982].

13.14.020 Scope.

This chapter outlines 10 criteria or factors, called matrices, which assess the development potential of rural properties based on resources unique to a particular site, and establishes the basis upon which detailed site information supplied by an applicant can be accepted in lieu of general data otherwise available to County Planning staff for matrix determinations. [Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].

13.14.025 Amendment.

Any revision to this chapter which applies to the Coastal Zone shall be reviewed by the Executive Director of the California Coastal Commission to determine whether it constitutes an amendment to the Local Coastal Program. When an ordinance revision constitutes an amendment to the Local Coastal Program such revision shall be processed pursuant to the hearing and notification provisions of Chapter 13.03 SCCC and shall be subject to approval by the California Coastal Commission. [Ord. 3330 § 1, 1982].

13.14.030 Definitions.

The following definitions shall apply to rural residential matrix determinations in addition to those found in the General Plan and Local Coastal Program Land Use Plan glossary.

(A)    Allowable Average Density. The matrix system shall allow averaging of parcel sizes in order to obtain required lot sizes. (No lot may be created, however, through use of the averaging provision which would be smaller than an absolute minimum parcel size established by the General Plan and Local Coastal Program Land Use Plan within the Coastal Zone except where allowed by a development permit.)

When two or more parcels are averaged for the purpose of creating a smaller parcel, the larger parcel(s) shall be appropriately conditioned so that the larger acreage may not be counted again toward other subsequent land divisions, and such conditions be required to be stated as restrictions in any deed conveying the larger acreage.

(B)    Area of Proposed Development Activities. Development areas include the portion or portions of the property which would be utilized by proposed development for building sites, septic systems, primary and secondary access roads and other development-related structures or facilities, such as water storage tanks.

(C)    Recently Active. A geologic feature (fault trace or landslide) which shows evidence of movement or activity within the last 10,000 years is considered recently active. [Ord. 4416 § 14, 1996; Ord. 4406 § 14, 1996; Ord. 4346 § 39, 1994; Ord. 3434 § 1, 1983; Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].

13.14.040 Application.

(A)    This chapter shall apply to the rural areas of the County outside of the urban services line and the rural services line (USL and RSL), and shall include all tentative map approvals for land divisions and all development permits issued pursuant to Chapter 18.10 SCCC. Included in these categories are all applications to create additional parcels, additional housing units, additional visitor accommodations, or additional organized camp facilities on land designated in the General Plan as suburban residential, rural residential, mountain residential, parks and recreation, resource conservation, or noncommercial agriculture. The development of farmworker housing as defined in SCCC 13.10.631(C) on property in the A (Agriculture) Zone District is an agricultural use and is not subject to the residential density determinations in this chapter. Existing development on a parcel shall be deducted from the intensity of use allowed by this chapter in determining the amount of additional development (if any) to be allowed on the property.

(B)    This chapter shall not prevent the development of a single residential unit on an existing legal parcel of record.

(C)    This chapter shall not require the decision-making body to approve the minimum lot sizes or maximum densities of use determined by the matrices of this chapter if a denial or modification of the project is required by the policies of the General Plan and Local Coastal Program Land Use Plan or by other overriding concerns which are reflected in findings required by State law or County ordinances.

(D)    If a use permit was issued and exercised prior to December 23, 1980, which allows the construction of two to four dwelling units on one parcel, and the appropriate findings for a land division can be made, the matrix system shall not be used to limit the division of that parcel into fewer lots than the number of dwelling units which were originally approved. The density of the proposed division may be deemed to comply with the General Plan by virtue of the fact that the approved use permit constitutes existing development. [Ord. 5321 § 6, 2019; Ord. 4416 § 15, 1996; Ord. 4406 § 15, 1996; Ord. 4346 § 40, 1994; Ord. 3594 § 1, 1984; Ord. 3434 § 2, 1983; Ord. 3330 § 1, 1982].

13.14.050 Rural residential density determinations.

In order to calculate the allowable average density, a parcel shall be evaluated based upon the following criteria (in order of occurrence):

(A)    Developable Land. Acreage of nondevelopable land (as defined in the General Plan and Local Coastal Program Land Use Plan glossary) must be subtracted from gross acreage to arrive at developable land.

(B)    Matrix Calculations. Developable land is evaluated through the criteria in the matrix system (SCCC 13.14.060) to arrive at a preliminary allowable average parcel size.

(C)    Overriding Minimum Acreage Policies. The parcel is examined to determine if it is subject to any overriding General Plan policies, or Local Coastal Program Land Use Plan policies, requiring a minimum gross acreage parcel size (e.g., watershed land, fire hazard areas, fault zones, etc.). Such minimum parcel size restrictions, if applicable, take precedence over the preliminary allowed average density in the event of a conflict. (See SCCC 13.14.070.)

(D)    Final Allowable Average Density. The matrix calculations in subsection (B) of this section shall become the final maximum allowable average density for the parcel unless modified pursuant to subsection (C) of this section. [Ord. 4346 § 41, 1994; Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].

13.14.060 Matrix calculation.

(A)    Individual matrix calculations are based upon a site-specific analysis of resources and constraints, using the best available data (see SCCC 13.14.080), for each of the following 10 matrices. Any property which is split by a General Plan or matrix designation shall have points awarded proportionate to the amount of developable acreage within each designation.

 

(1)
LOCATION MATRIX*

TYPE OF ACCESS 

PLAN DESIGNATION CATEGORY

All Lots Fronting On or Within 500' (Road as Traveled) of a County Maintained Road and Accessed from That Road

All Lots Served by a Private Road 18-Foot Width

Lots Served by a 12-Foot Road with Turnouts

(Suburban) (1—5 acre areas)

15

13

12

(Rural Residential Rural Homesites) (2-1/2—20 acre areas)

10

8

7

(Mountain Residential) (10—40 acre areas)

5

2

0

*    In the Coastal Zone portion of the North Coast and Bonny Doon Planning Areas, prohibit new land divisions located more than one-half mile by road from a publicly maintained road. (GP/LUP Policy 6.5.10)

 

(2)
GROUNDWATER QUALITY MATRIX

TYPE OF SUPPLY 

AREA

County or Municipal Water District

Private or Mutual Well System

Private or Mutual Surface Diversion

0

Groundwater Supply at or Exceeding Safe Yield

0

0

0

I

Inadequate Quantity Poor Quality

2

1

0

II

Inadequate Quantity Good Quality

5

4

2

III

Adequate Quantity Poor Quality

7

5

3

IV

Adequate Quantity Good Quality

10

8

5

 

(3)
WATER RESOURCES PROTECTION MATRIX

GROUNDWATER BASIN TYPE 

CHARACTERISTICS OF SANITATION SYSTEM

Outside Primary Recharge and Water Supply Watershed Areas

Outside Primary Recharge Area but Within Water Supply Watershed

Within Primary Recharge Area but Outside Water Supply Watershed

Within Both Primary Recharge and Water Supply Watershed Areas

Public Sanitation System

10

9

8

7

Package Treatment Plant or Septic System Maintenance District

9

8

7

6

Septic Systems in Areas without Known Problems

6

5

4

3

Septic Systems within Septic Tank System Problems Areas

3

2

1

0

 

(4)
TIMBER RESOURCES MATRIX 

DISTANCE FROM URBAN SERVICES LINE

PARCEL SIZE*

Less than 20 Acres

20 Acres or Larger

Less than 1/2 mile

8

0

1/2—2 miles

6

0

More than 2 miles

4

0

*    Properties without a “timber resources” designation on the General Plan or TP zoning receive a score of 10.

 

(5)
BIOTIC RESOURCE MATRIX 

 

TYPE OF BIOTIC RESOURCE

POINTS

I

Development Activities Outside Designated Sensitive Habitats

10

II

Development Activities Proposed within Sensitive Habitat

5

III

Development Activities Proposed within an Area of Critical Wildlife, Vegetation or Rare Plant Habitats

0

*IV

Sensitive Habitats

0

*    In the Coastal Zone, development must comply with the standards of the sensitive habitat protection ordinance.

 

(6)
EROSION MATRIX

AVERAGE SLOPES 

BEDROCK GEOLOGY

0—15%

16—30%

31—50%

Granitics, Metamorphics, Terrace Deposits

10

9

7

Santa Cruz Mudstone, Mindego, Purisima, Locatelli, Monterey, Alluvium

10

8

5

Lompico, Vequeros, Lambert, Butano, Zayante, San Lorenzo

8

5

2

Santa Margarita, Aromas

6

3

0

 

(7)
SEISMIC ACTIVITY MATRIX

AREAS OF LIQUEFACTION 

FAULT ZONE

Very High Potential

Moderately High Potential

Moderate Potential

Low Potential

No Potential

San Andreas

San Gregorio

0

0

0

0

0

Zayante

0

1

2

3

3

Corralitos

1

2

3

4

5

Sargent, Butano

3

4

5

6

7

None

4

6

8

9

10

 

(8)
LANDSLIDE MATRIX

AVERAGE SLOPES 

BEDROCK GEOLOGICAL CONDITIONS

0—15%

16—30%

31—50%

Alluvium

10

9

(N/A)

Granitics, Metamorphics, Terrace Deposits

10

10

7

Santa Margarita, Lompico, Santa Cruz Mudstone, Mindego, Locatelli, Monterey

10

9

7

Vaqueros, Butano, Purisima, Zayante, Lambert Shale

9

8

5

San Lorenzo

8

5

2

Aromas

6

3

0

Evidence of recently active landslides on the property in the area of proposed development activities*

2

0

0

*    Properties having a landslide that could adversely affect the stability of the proposed development, or that indicates general geologic conditions of instability on the property, must be evaluated in the bedrock category.

 

(9)
FIRE HAZARD MATRIX

Location and Road Standards 

 

Entire Property Outside Critical Fire Hazard Area on 18-Foot Road

Entire Property Outside Critical Fire Hazard Area on 12-Foot Road with Turnouts

Parts of Property in Critical Fire Hazard Area with Building Site Located Outside with 18-Foot Road

Parts of Property in Critical Fire Hazard Area with Building Site Located Outside with 12-Foot Road with Turnouts

Building Sites within Mitigatable Critical Hazard Areas

Less Than 10 Minutes Response Time on Non-Dead End Road

15

12

10

8

6

Less Than 10 Minutes Response Time on Dead End Road with Secondary Access

13

10

8

6

4

10—20 Minutes Response Time on Non-Dead End Road

10

8

6

4

2

10—20 Minutes Response Time on Dead End Road with Secondary Access

8

6

4

2

0

(10)
CUMULATIVE CONSTRAINT POINTS

(a)    Cumulative constraint points shall be deducted from the total matrix score based upon the following criteria:

(i)    If the proposed division receives a zero on two matrices, five points shall be subtracted from the matrix.

(ii)    For each additional zero the proposed division receives, five additional points shall be subtracted from the matrix.

(b)    Preliminary average allowable density is determined by referring the total numerical score (based upon the 10 matrices above) to the following tables:

(i)    Suburban Residential Table. (To be used for any portion of the property outside the urban services line and rural services line designated as suburban residential, one to five acres/unit.)

Total Number of Points Obtained

Minimum Average Parcel Size Allowed for Development

60 and under

5 acres

61—65

4-1/2 acres

66—70

4 acres

71—75

3-1/2 acres

76—80

3 acres

81—85

2-1/2 acres

86—90

2 acres

91—100

1 acres

The minimum parcel size in Suburban designations without public water service shall be two and one-half acres.

(ii)    Rural Residential Table. (To be used for any portion of the property designated as rural residential or noncommercial agricultural in the following case: where the Agricultural Policy Advisory Commission has made a written finding that the land is not viable for commercial agricultural and where less than 50 percent of the land area within one-quarter mile of the subject property is designated agricultural resource, mountain residential, or resource conservation and all proposed building sites are within one-half mile of a through County-maintained road (see G.P. Policy 5.14.12).

Total Number of Points Obtained

Minimum Average Parcel Size Allowed for Development

0—20

20 acres

21—40

15 acres

41—60

10 acres

61—80

5 acres

81—100

2-1/2 acres

(iii)    Mountain Residential/Noncommercial Agricultural/Resource Conservation Table. (To be used for any portion of the property designated as mountain residential, noncommercial agricultural, or resource conservation.)

Total Number of Points Obtained

Minimum Average Parcel Size Allowed for Development

0—20

40 acres

21—30

35 acres

31—40

30 acres

41—55

25 acres

56—70

20 acres

71—80

15 acres

81—100

10 acres

[Ord. 4836 § 116, 2006;* Ord. 4416 §§ 16—19, 1996; Ord. 4406 §§ 16—19, 1996; Ord. 4346 §§ 42—46, 1996; Ord. 3594 § 2, 1984; Ord. 3434 § 3, 1983; Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].

    Code reviser’s note: Ord. 4836 had two sections numbered “116.”

13.14.070 Overriding minimum acreage maximum density policies.

In order to calculate allowable average parcel size and density under overriding policies, the total acreage must be compared against the following applicable sections of the General Plan and Local Coastal Program Land Use Plan and County Code. (See General Plan and Local Coastal Program Land Use Plan Figure 2.2 for special land division and density requirements.)

GENERAL PLAN AND LOCAL COASTAL PROGRAM LAND USE DESIGNATION, RESOURCE OR CONSTRAINT

GENERAL PLAN AND LOCAL COASTAL PROGRAM SECTION OR POLICY REFERENCE

Land Use Designation

Agriculture

 

• Commercial

5.13.14 and 5.13.19

• Noncommercial

5.13.18 and 5.14.12

Suburban Residential

2.6.1 and 2.6.2

Rural Residential

2.5.1 and 2.5.2

Mountain Residential

2.4.1

Resource Conservation

5.11.6 and 2.4.1

Parks, Recreation and Open Space

7.1.3

Resource

Agricultural Lands

5.13.14 and 5.13.19

Special Forests

5.1.5

Grasslands

5.1.5

Mineral Lands

5.16.5

Timber Lands

5.12.4

Watersheds

 

• Water Supply Watersheds

5.5.6

• Least Disturbed Watersheds

5.5.7

• Reservoir Protection Areas

5.5.14

Groundwater Recharge Lands

5.8.2

Constraint

Coastal Hazard Areas

6.2.15, 6.2.17 and 6.2.18

Critical Fire Hazard Areas and Access Standards

6.5.4 and 6.5.5

Flood Hazard Areas (100-year floodplain)

6.4.5 and 6.4.6

Seismic Review Zones (fault zones)

6.1.12

[Ord. 4346 § 47, 1994; Ord. 3434 § 4, 1983; Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].

13.14.080 Resource and constraint data.

Data used to determine parcel-specific resources and constraints shall be the most accurate available. Staff determinations shall be based upon the existing database (see table below) and an on-site inspection. An applicant may, however, submit or may be required to submit more detailed information which can serve as the basis for an updated staff evaluation (submitted as part of the environmental review for the project) as indicated in the table below:

Environmental Data

Officially Adopted Data Source

Acceptable New Information Source

Slopes

USGS Slope Maps

A detailed slope map prepared by a civil engineer or land surveyor

Riparian Corridors

USGS maps in conjunction with watershed staff field review and General Plan policies

A detailed map of slopes and the extent of riparian vegetation prepared by a qualified professional

100-Year Floodplain

Most recent Federal flood insurance maps; Local Coastal Program Land Use Plan resource and constraint maps

An investigation prepared by a qualified registered engineer or registered geologist which establishes accurate boundaries of the 100-year flood

Agricultural Lands

Agricultural Resources Map, as adopted and amended by the Board of Supervisors, Local Coastal Program Land Use Plan resources and constraints maps

Agricultural Policy Advisory Commission determination that land is or is not viable with approval of the Board of Supervisors

Road Standards

Field check of roads per General Plan requirements

Applicant may improve roads to standards

Water Quality/Quantity Areas

Measure J groundwater quality/quantity maps; Local Coastal Program Land Use Plan resource and constraint maps

A report conducted by a hydrogeologist which demonstrates that the region in which the parcel is located is or is not experiencing water quality or availability problems, and that the proposed water use will or will not contribute to an adverse cumulative water quality or quantity impact

Overdrafted Aquifers

Maps approved by the affected water district and adopted and amended by the Board of Supervisors

 

Primary Groundwater Recharge Areas

Measure J primary groundwater recharge areas maps; Local Coastal Program Land Use Plan resource and constraint maps

A report conducted by a soils engineer and registered geologist or hydrogeologist which establishes that, based upon local soils, bedrock, and regional hydrogeologic conditions, a particular area is or is not part of a primary groundwater recharge area

Water Supply Watershed

General Plan resources and constraint maps; Local Coastal Program Land Use Plan resource and constraint maps

Information which indicates that a property does or does not lie within a designated water supply watershed

Septic System Problem Areas

Measure J septic system problem areas map

Certification from County Environmental Health that the property does or does not lie in an area of experienced septic problems

Timber Resources

General Plan resource and constraint maps; Local Coastal Program Land Use Plan resource and constraint maps

Actual field data which concludes that the property does or does not contain marketable timberlands

Wildlife Resources and Sensitive Habitats

Measure J resources and constraint maps, Local Coastal Program Land Use Plan resource and constraint maps

A biotic report prepared by a biologist which indicates the absence or presence of wildlife habitats or unique or rare plant communities or individuals on the property

Geologic Rock Type

USGS compilation map of rock types

A geologic report prepared by a registered geologist which accurately maps fault traces, landslides and bedrock geology, or review and update of map by Planning staff geologist

Fault Zones

Local Coastal Program Land Use Plan and General Plan resources and constraint maps and State and USGS maps

 

Liquefaction Areas

Seismic safety element liquefaction map; Local Coastal Program Land Use Plan resource and constraint maps

A report by a registered engineering geologist which indicates that the building site will or will not be subjected to liquefaction

Landslides

Seismic safety element map combined with Planning staff geologist field inspections

A geologic report prepared by a registered geologist which accurately maps fault traces, landslides and bedrock geology

Fire Response Time

Fire response time map prepared by County officials

A letter from the Chief of the Fire District responsible to serve as a field-measured response time

Critical Fire Hazard Areas

Field inspection combined with aerial photo survey; General Plan resource and constraint maps are general guidance

In mitigable areas (see General Plan) with Fire Official’s approved mitigation measures; in other areas, based upon on-site vegetation (assuming no illegal or unauthorized vegetation clearance has taken place)

[Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3023, 1980].

13.14.090 Fees.

Fees for staff time required to implement this chapter shall be set forth in a separate fee resolution by the Board of Supervisors. [Ord. 3330 § 1, 1982; Ord. 3072, 1981; Ord. 3026, 1980].