Chapter 17.10
STANDARDS AND DESIGN CRITERIA

Sections:

17.10.010    Applicability.

17.10.020    General layout.

17.10.030    Specific standards – Streets.

17.10.040    Specific standards – Lots.

17.10.050    Minimum improvements.

17.10.060    Minimum improvements – When applicable.

17.10.070    Deviations and variances from these standards.

17.10.010 Applicability.

The standards and design criteria of this chapter shall be met for all subdivisions unless variances from these standards are approved in accordance with MTMC 17.10.070. (Ord. 2658 § 2, 2015).

17.10.020 General layout.

The subdivider shall ensure that the plat conforms to the following standards:

A. Lots shall provide suitable areas for buildings in areas of the lot that avoid geologic hazard areas, or follow the procedures for alteration or development described in Chapter 16.15 MTMC (Critical Areas).

B. The site shall have suitable access and circulation, as follows:

1. Where possible, streets shall run parallel to topography requiring minimum cuts or fills.

2. Finished grade of streets shall not exceed 15 percent.

3. Streets shall continue to boundaries of tract unless it can be demonstrated that no future connections to the abutting property are planned or otherwise feasible.

4. Streets shall intersect at right angles with no variations of more than 25 degrees.

5. Streets should be located so that jogs are avoided at intersections.

6. Where possible all lots shall be served by streets within the subdivision rather than having numerous access points on an existing City street.

7. Cul-de-sacs having a maximum length of 300 feet must have a minimum radius of 35 feet, and a minimum right-of-way width of 50 feet. Cul-de-sacs of a length greater than 300 feet shall have a minimum radius of 45 feet, and a minimum right-of-way width of 60 feet.

C. Vehicle turnaround easements provided on private property shall generally be designed as illustrated in Figure 1. Variations for this design may be allowed if the City Engineer determines that the proposed turnaround easement design satisfies the intent of the design shown in Figure 1:

Figure 1

Note: Two lot subdivisions utilizing flag lots shall be exempt from this requirement, unless specifically required as a condition of approval of the subdivision. (Ord. 2729 § 10, 2018; Ord. 2701 § 2, 2016; Ord. 2658 § 2, 2015).

17.10.030 Specific standards – Streets.

The following specific standards shall apply in the design of streets:

A. Intersections. At street intersections, property line corners shall be rounded by an arc, the minimum radius of which shall be 10 feet. For intersections of arterial streets, the minimum radii shall be 20 feet.

B. Streets and rights-of-way shall conform to the cross-section designs of the Transportation Master Plan and to the most current version of City of Mountlake Terrace Engineering Details and Specifications at the time of application submittal.

C. Access easements serving no more than two nonresidential lots or three single-family lots shall have a minimum width as specified in MTMC 19.95.030(K).

D. Flag or panhandle lots may be permitted where the total division consists of two lots with a minimum panhandle width of 12 feet. (Ord. 2792 § 9, 2021; Ord. 2729 § 11, 2018; Ord. 2701 § 3, 2016; Ord. 2658 § 2, 2015).

17.10.040 Specific standards – Lots.

A. Minimum lot size and dimensions shall conform to the zoning district in which the subdivision is proposed.

B. Density shall relate to the zoning district in which the subdivision is located, subject to density modification allowable under a planned unit development.

C. Each lot shall have frontage on a public street, private street, or an access easement, which frontage shall be no less than 12 feet for panhandle lots, or the minimum lot width at the street frontage specified in the zoning district in which it is located. (Ord. 2729 § 12, 2018; Ord. 2701 § 4, 2016; Ord. 2658 § 2, 2015).

17.10.050 Minimum improvements.

A. Streets and associated right-of-way improvements shall be constructed and graded to full width of the cross-section specified for the street type and surfaced with asphalt, concrete or LID paver system, as approved by the City Engineer, to the width prescribed by MTMC 17.10.030(B).

B. Curbs and gutter sections as prescribed by MTMC 17.10.030(B).

C. Stormwater systems designed to meet LID standards of Stormwater Manual.

D. A water distribution system, providing connections for each lot, including the locations of fire hydrants.

E. All basic utilities including water, sewer, natural gas, and electricity, and also easements for accessory utilities including telephone and cable television transmission lines. All utilities shall be placed underground. Where subdivisions necessitate frontage improvements, such improvements shall include conduit as specified by the City Engineer to facilitate future undergrounding of existing overhead utilities.

F. Complete half-street improvements along the full frontage of the property to be divided, including installation of all improvements as prescribed in MTMC 17.10.030(B). In this context, half-street improvements mean all prescribed improvements to the centerline of the right-of-way and as additionally needed to facilitate two-way traffic.

G. Sanitary Sewer Facility Extensions. Every subdivision shall be provided sanitary sewer facilities and the subdivider shall extend main lines where necessary to achieve this improvement.

H. Monuments shall be placed at all street intersections, boundary angle points, points of curves in streets, and at such intermediate points as required by the City Engineer. The monuments shall be of stone or concrete filled pipe or tile, weighing at least 50 pounds, capped with standard markers. Street monuments shall be finished street grades and in paved streets shall be enclosed in a standard monument case. All lot and block corners shall be set with an iron pipe at least 18 inches in length after all grading work is finished. (Ord. 2729 § 13, 2018; Ord. 2701 § 5, 2016; Ord. 2658 § 2, 2015).

17.10.060 Minimum improvements – When applicable.

The minimum improvements included in MTMC 17.10.050 shall apply to all subdivision types except for boundary line adjustments. The developer shall be required to improve all existing rights-of-way adjacent to or within the property being subdivided to meet the standards included in MTMC 17.10.050, unless those standards are already met. All proposed access routes, whether intended to be public right-of-way or private easement, shall be improved by the developer in a manner consistent with the standards included in MTMC 17.10.050. (Ord. 2701 § 6, 2016; Ord. 2658 § 2, 2015).

17.10.070 Deviations and variances from these standards.

Deviations from the dimensional standards of this chapter may be considered under either the provisions of planned unit development in Chapter 19.115 MTMC, or the variance procedures of Chapter 19.110 MTMC. Variances from all other standards of this chapter may be considered only under the variance provisions of Chapter 19.110 MTMC. (Ord. 2658 § 2, 2015).