17.15.030 Approval criteria – Preliminary plat

17.15.030 Approval criteria – Preliminary plat.

A. General Approval Criteria. The city may approve, approve with conditions or deny a preliminary plat based on the following approval criteria:

1. The proposed preliminary plat complies with all of the applicable code sections and other applicable ordinances and regulations. At a minimum, the provisions of this chapter and the provisions of the underlying zoning district shall apply. Where a variance is necessary to receive preliminary plat approval, the application shall also comply with the relevant sections of Chapter 18.160 TMC, Variances;

2. The proposed plat name is not already recorded for another subdivision, and satisfies the provisions of ORS Chapter 92;

3. The proposed streets, roads, sidewalks, bicycle lanes, pathways, utilities, and surface water management facilities are laid out so as to conform or transition to the plats of subdivisions and maps of major partitions already approved for adjoining property as to width, general direction, and in all other respects; and are consistent with the city’s transportation system plan. All proposed public improvements and dedications are identified on the preliminary plat; and

4. All proposed private common areas and improvements (e.g., homeowner association property) are identified on the preliminary plat.

1. Minimum and Maximum Density Requirements. When lots are created through a planned unit development or subdivision, the development shall achieve a minimum of 40 percent and a maximum of 100 percent of the dwelling unit density permitted by the applicable zoning district. The minimum density provision shall not apply to parcels that are smaller than one acre. For purposes of this section, the minimum number of dwelling units required shall be determined by multiplying the maximum density by 0.4. The result shall be rounded up for any product with a factor of 0.5 or greater and rounded down for any product with a fraction of less than 0.5.

a. The number of dwelling units permitted on a parcel of land is calculated after determining how much of the area is unconstrained. Constraints include undevelopable lands, area devoted to street rights-of-way and other infrastructure, and area devoted to nonresidential uses. Dedicated parkland (when accepted by the city) is not considered constrained land for the purposes of calculating density. TMC Title 18 permits limited density transfers in the case of steep slopes (TMC 18.80.040) and wetlands and riparian setbacks (TMC 18.85.040), subject to conditions described in those sections. The following steps describe how to calculate density. (For density calculation in the R2 zone, refer to TMC 18.40.060. Do not use the method below for the RM-HD zone.)

i. Step 1. Determine the amount of land, in acres, intended for development.

ii. Step 2. Subtract areas either devoted to or to be developed as commercial and other nonresidential developed uses.

iii. Step 3. . Subtract undevelopable lands (as defined in Chapter 18.15 TMC).

iv. Step 4. Multiply the result of Step 3 by 0.76 to account for a 24-percent standard deduction for infrastructure.

v. Step 5. Multiply the result of Step 4 by the gross base density, which is determined by dividing 43,560 (one acre) by the minimum lot size of the zone in question (e.g., in the RS-5 zone, gross base density is 5.445; in the RS-7 and RS-MH zones it is 7.26).

vi. Step 6. Round the result of Step 5 to nearest whole number.

b. The preceding steps may expressed by the following formula:

D = (A – N – U)RB, where

D = density permitted (in number of dwelling units)

A = total site area (in acres)

N = area devoted to nonresidential uses (not including parks, open space, infrastructure or undevelopable lands)

U = undevelopable lands

R = 0.76 standard deduction for right-of-way and other infrastructure

B = base density (43,560 divided by the minimum lot size of the zone).

The resulting density (D) is the number of units that may be distributed on the developable portions of the site.

C. Block and Lot Standards. All proposed blocks (i.e., one or more lots bound by public streets), lots, and parcels conform to the specific requirements below:

1. All lots shall comply with the lot area, setback, and dimensional requirements of the applicable zone district, and the standards of TMC 17.10.050(J), Street Alignment and Connections.

a. Single-family residential lot sizes may be averaged to allow lots less than the minimum lot size in the RS-5 and RS-7 residential districts, as long as the average area for all lots is not less than allowed by the district. In order to prevent exceeding the maximum allowable densities, no lot shall be created that can be divisible in the future unless a redivision plan is filed for the subject lot, pursuant to subsection (F) of this section. No lot created under this provision shall be less than 85 percent of the minimum lot size allowed in the zone. For example, in the RS-5 zone the following three lots could be created from a 24,000-square-foot tract: 6,800 square feet; 8,000 square feet; and 9,200 square feet.

b. In the high-density S&MF residential (RM-HD) zoning district, individual lots may not be created that are too small to provide a residential building footprint, adequate access, any required undeveloped or landscaped areas, and covered off-street parking for at least two dwelling units.

2. Setbacks shall be as required by the applicable zoning district, unless a PUD is approved with different setbacks.

3. Each lot shall conform to the standards of TMC 17.10.060, Vehicular access and circulation.

4. Landscape or other screening may be required to maintain privacy for abutting uses and buffering for pathways, through lots abutting an arterial or collector street, grade changes and retaining walls, development on flag lots, and similar situations, consistent with the provisions of TMC Titles 17 and 18 and Chapter 18.105 TMC.

5. In conformance with the Uniform Fire Code, a 20-foot-wide fire apparatus access drive shall be provided to serve all portions of a building that are located more than 150 feet from a public right-of-way or approved access drive. See also TMC 17.10.060, Vehicular access and circulation.

6. Where a common drive is to be provided to serve more than one lot, a reciprocal easement, which will ensure access and maintenance rights, shall be recorded with the approved subdivision or partition plat.

D. Conditions of Approval. City staff, planning commission, or city council may attach such conditions as are necessary to carry out provisions of this code and other applicable ordinances and regulations. When not voluntarily accepted by the applicant, conditions shall be roughly proportional to the impact of development, and the written findings and decision shall include findings of proportionality.

E. The city may require that reserve strips be granted to the city for the purpose of controlling access to adjoining undeveloped properties.

F. Future Redivision Plan. When subdividing or partitioning tracts into large lots (i.e., greater than two times or 200 percent the minimum lot size allowed by the underlying land use district), the city shall require that the lots be of such size, shape, and orientation as to facilitate future redivision in accordance with the requirements of the zoning district and this code. A redivision plan shall be submitted that identifies:

1. Potential future lot division(s) in conformance with the housing and density standards of the underlying zoning district;

2. Potential street right-of-way alignments to serve future development of the property and connect to adjacent properties, including existing or planned rights-of-way;

3. A disclaimer that the plan is a conceptual plan intended to show potential future development. It shall not be binding on the city or property owners, except as may be required through conditions of land division approval. Development activities that prevent implementation of the redivision plan shall not be permitted unless they achieve the housing densities and street connections required by the applicable zoning district and this chapter. The city may require dedication and improvement of rights-of-way within the future plan area to provide needed secondary access and circulation.

G. Compliance. All submittals shall demonstrate compliance with Chapter 17.10 TMC, Development and Design Standards, and Chapter 18.85 TMC. [Ord. 818 § 2 (Exh. A (§ 8-2.330)); Ord. 793; Ord. 777; Ord. 692 § 13.]