Chapter 17.16 DESIGN PRINCIPLES AND DEVELOPMENT STANDARDS

The most recent edition of the Standard Specifications for Road, Bridge and Municipal Construction adopted by the Washington State Department of Transportation shall be hereinafter referred to as the “standards” and the standards, together with the laws of the state and the ordinances of the city, so far as applicable, shall apply except as amended or superseded. The amendments to the above code are hereby adopted by reference. (Ord. 2450 § 1, 2010; Ord. 2316 § 2 (Exh. A), 2006).

17.16.020 Inspection, approval and fees.

The engineering department shall be responsible for the plan check supervision, inspection and acceptance of all subdivision improvements and shall charge the subdivider in the amount of the hourly cost to the city. The hourly cost shall include the wages of the inspector and the city’s cost for fringe benefits calculated on an hourly basis. Developer shall provide an engineer at the site to monitor all improvements and to certify to the city that construction has been completed according to plans and specifications and that it meets all applicable codes and standards of the engineering profession.

A. Plan Requirements for Minimum Improvement. Prior to the construction of any minimum improvements, as approved upon the preliminary plat, the subdivider shall furnish certain construction plans as follows:

1. Plans for improvements shall be prepared by a registered civil engineer and shall be in accordance with city standards. The plans shall be at a horizontal scale of one inch representing 50 feet and the vertical scale at one inch representing five feet or one inch represents two feet as approved by the city engineer. The plans shall show all existing and proposed topography, utilities, grades, subdivision lines, rights-of-way and all other features required by the city engineer. A minimum of the below shall be submitted as determined by the city engineer:

a. Plan-profile map for streets and drainage;

b. Plan-profile map for sanitary sewers;

c. Plan map for water system.

2. The plan maps, plan-profile maps and specifications shall be submitted to and approved and signed thereon by the city engineer prior to proceeding with the proposed improvements. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.030 Required improvements.

The following tangible improvements shall be installed in accordance with specifications and standards approved by the engineering department before a final plat is submitted: graded and paved streets and alleys, curbs and gutters, sidewalks, monuments, sanitary sewers, stormwater facilities, street lights, water mains, and street name and traffic signs, together with all appurtenances thereto. (Ord. 2607 § 1 (Exh. A), 2017; Ord. 2316 § 2 (Exh. A), 2006).

17.16.040 Mitigation of impact of development on schools.

Repealed by Ord. 1978. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.050 Mitigation of impact of development on park and recreation facilities.

A. Use of Fund Authorized. The city may require a subdivider to contribute to an environmental impact mitigation fund administered by the city to pay the reasonable cost of achievable measures for mitigating the adverse environmental impact of said subdivision remaining after he has complied with all local, state, and federal regulations pertaining to this project. The requirement of paying the fund may be imposed as a condition of preliminary plat approval. Where payment is required, payment must be delivered to the city prior to final plat approval. The city shall expend the payment to mitigate the environmental impact for which the funds were exacted. If the funds cannot reasonably be applied within six years to mitigate the impact for which the funds were collected, then the funds shall be refunded to the subdivider.

B. Environmental Impact Mitigation Fund is Necessary for Parks and Recreation. The city finds that, among other impacts, the development of land for single-family or multifamily residential purposes imposes an adverse environmental impact upon the park and recreation facilities serving Enumclaw by adding population. The city finds that the subdivider should help to mitigate this environmental impact by dedicating land or paying into an environmental impact mitigation fund dedicated to purchasing or improving park and recreational facilities.

C. Environmental Impact Mitigation Fees Established.

1. The subdivider shall dedicate to the city, or provide fees in lieu, based on a rate of two acres per 1,000 ultimate residents. This requirement may be imposed as a condition of preliminary plat approval. The following formula shall be used to determine the amount of park land to be dedicated: [2.0 x (no. units) x (persons/unit)] / 1,000 = acres to be dedicated.

2. Payment in lieu of land provision where, with respect to a particular subdivision, the dedication of land does not meet the criteria listed below, the city shall require the subdivider to deposit a cash payment or letter of credit. These funds shall be deposited into an environmental impact mitigation fund dedicated to provide land or improvements for park and recreation facilities. Payment shall be required prior to final plat approval. All fees collected shall be used for the acquisition and/or improvement of neighborhood parks which will serve the subdivision.

3. Payment in lieu of land criteria may be required by the administrator under the following conditions:

a. Area to be dedicated is under five acres in size; or

b. Inaccessible or unusable due to topography or drainage; or

c. Is not centrally located to existing or anticipated subdivisions; or

d. The proposed subdivision would be adequately served by existing park land.

4. Determination of payment shall be determined by the fair market value of the land to be subdivided by a certified appraiser. The subdivider shall provide proof of the fair market value by providing a signed letter of a certified appraiser. If the city determines that said value is inaccurate the city shall provide certified appraisals from three separate appraisers and shall use the figure that falls between the high and low estimate. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.060 Large tracts or parcels.

When land is subdivided into larger parcels than ordinary lots or blocks, such parcels shall be arranged so as to allow for the opening of future streets and logical further subdivisions. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.070 Conformity to comprehensive plan.

A. The proposed subdivision shall conform to the policies reflected by the comprehensive plan and shall provide for such requirements as are contained in the implementation of the plan in part by the zoning and subdivision ordinances.

B. The subdivider shall make available for public acquisition such lands in the area to be subdivided as may, under the policies reflected by the comprehensive plan or as implied in part by the zoning and subdivision ordinances, be desirable or are designated for parks, playgrounds, public buildings, etc.

C. Natural features such as trees, ridgelines, hilltops, and views shall be preserved and kept in a natural state to the maximum extent possible.

D. A stormwater facility easement, parallel to and measured in terms of the centerline of all minor and major watercourses, shall be required. In the determination of the dimension of such easements and the classification of watercourses the planning commission and staff shall be guided by the comprehensive drainage plan. Any disturbance of the natural state or construction in the designated easement will not be allowed unless approval is received from the planning commission, concurrent with the approval of the subdivision. In all cases, the bank of the watercourse shall be preserved in as natural a state as is practical.

E. In all subdivisions encompassing an area of five acres or more, the approval of the United States Department of Agriculture Soil Conservation Service must be obtained to assure that soil erosion will be held to a minimum. This includes the removal of trees, grading, excavation and land fill. (Ord. 2607 § 1 (Exh. A), 2017; Ord. 2316 § 2 (Exh. A), 2006).

17.16.080 Permits.

Prior to proceeding with subdivision improvements, the subdivider shall make application for such permits from the city as are necessary. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.090 Monuments.

Concrete monuments shall be set at all corners of the subdivision, at all points where the street lines intersect the exterior boundaries of the subdivision, at angle points and points of curve in each street, and at all street intersections. All surveys shall be of second degree accuracy. The use of state plan coordinates is encouraged. All other lot corners shall be marked with a permanent suitable metal marker not less than three-eighths-inch in diameter and 24 inches long and driven flush with the finished grade. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.100 General design criteria.

Streets, blocks, and lots shall conform to the most advantageous development of contiguous area and neighborhoods and shall provide for the following:

A. Continuity and connectivity of appropriate streets;

B. Streets intersect at right angles or as nearly so as possible;

C. Streets continuing to boundaries of the tract;

D. All alleys, except a Type 9 limited local access alley, shall be provided with a parallel service street. (Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.110 Streets.

A. Widths and Classifications. See EMC 12.18.057.

B. Comprehensive Plan. Where the comprehensive plan, including the circulation element thereof, and/or the six-year transportation improvement program indicates the necessity of new or additional right-of-way, either in regard to right-of-way width or length, whether such need of additional right-of-way appears within a new subdivision or replat, or along the boundaries of a new subdivision or replat, such required right-of-way or portion thereof belonging to the subdivider shall be dedicated to the city by the filing of such plat or replat.

C. Clearing and Grading. All streets, roads and alleys shall be graded to their full width so that pavement and sidewalks can be constructed on the same plane. Before grading is started, the entire right-of-way area shall be cleared and grubbed of all stumps, roots, brush, organic and unsuitable soil, other objectionable materials and all trees not intended for preservation.

D. Roadway Surfacing. After preparation of the subgrade, the road bed shall be surfaced with material required by city standards.

E. Relation to Adjoining Street System. The street system shall extend existing streets at the same or greater width, but in no case less than the required minimum width.

F. Arterials and Intersections. Streets intersecting with existing or proposed public highways and minor arterials as shown on the comprehensive plan shall be kept to a minimum, subject to review and approval by the public works department.

G. Maximum Grades.

1. Minor arterials, seven percent;

2. All other streets, alleys, etc., the maximum grades shall not exceed 10 percent, unless otherwise approved by the public works director;

3. Grades of pedestrian ways or crosswalks shall not be more than five percent, unless otherwise approved by the public works director;

4. All vertically aligned profile grade changes shall be connected with a vertical curve which shall have a minimum sight distance as indicated for the respective type of street in EMC 12.18.057.

H. Minimum Curve Radii. See EMC 12.18.057.

I. Minimum Tangent Distances Between Curves.

1. Minor arterials, 200 feet;

2. All other street types, 100 feet;

3. Alleys and limited access, 50 feet.

J. Intersections. At street intersections, right-of-way lines or property line corners shall be rounded by an arc, the minimum radii of which shall be 20 feet. In business districts, a 15-foot chamfer distance and resultant chord may be substituted for such arc which shall be approved by the public works director.

K. Street Intersection Offset. Street jobs with centerline offsets of less than 200 feet shall not be allowed.

L. Cul-de-Sacs. Cul-de-sacs should be avoided, but may be permitted if it can be demonstrated that development of a through street is not practical given the constraints of natural features or existing plats and development; and provided, they do not exceed 500 feet in length, which length the administrator can waive if the street is expected to eventually be extended so as to no longer be a dead end. Cul-de-sacs shall not have a right-of-way radius less than that indicated in EMC 12.18.057.

1. The city may approve a T- or Y-shaped paved area in lieu of a cul-de-sac.

2. The length of a cul-de-sac shall be measured along the centerline of the street from the public right-of-way of the street intersection to the center of the cul-de-sac.

M. Horizontal Curves. Where a deflection angle of more than 10 degrees in the alignment of a street occurs, a minimum curve radius shall be designed, subject to review and approval by the public works department. See EMC 12.18.057.

N. Signs. All traffic control, street name and regulatory signs shall be supplied and installed by the developer to city specifications.

O. Access to Water. In all subdivisions bordering publicly owned or controlled bodies of water there shall be provided one or more dedicated rights-of-way to the low water mark, such rights-of-way having a minimum width of 60 feet and capable of being improved in accordance with this title.

P. Two Places of Access. Each subdivision shall have at least two places of access, except for those subdivisions in which the only dedicated street is a cul-de-sac.

Q. Full Width Streets. All internal streets shall be platted at full width, and no boundary streets at less than full width shall be allowed unless required to provide right-of-way for streets and arterials designated by the transportation element of the comprehensive plan.

R. Increased Right-of-Way Requirements in Commercial Districts. The city may require that street widths in commercial areas be increased to provide for traffic movement, additional parking or to reduce or eliminate traffic congestion.

S. Private Streets and Reserve Strips. There shall be no private streets in any subdivision, except as permitted in EMC 17.08.120, and every lot and block shall be served from an accessible street. There shall be no privately held or owned reserve strips paralleling or terminating street ends or otherwise controlling access to streets. (Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.120 Planting strips.

Planting strips in residential subdivisions shall be located between the curb and sidewalk. Planting strips in commercial and industrial subdivisions shall be located contiguous to the property line. Utilities installed in the planting strip shall be at a depth and in position to allow the planting of trees. (Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.130 Curbs and gutters.

The subdivider shall provide permanent concrete curbs and concrete gutters according to city standards. (Ord. 2607 § 1 (Exh. A), 2017; Ord. 2316 § 2 (Exh. A), 2006).

17.16.140 Sidewalks, pedestrian walkways, urban trails.

A. Sidewalk Location. Sidewalks shall be installed by the subdivider on both sides of streets, except on Type 9 or 10 streets, according to city standards. Sidewalks shall be located within the right-of-way contiguous to the property line to prevent interference or encroachment by fencing, walls, hedges or other plantings or structures in residential subdivisions and along the curb in commercial and industrial subdivisions. Where a subdivision abuts existing roads, sidewalks or walkways will be required to be installed in or adjacent to the abutting right-of-way. See subsection D of this section.

B. Continuity, Connectivity and Safety. Additional sidewalks, pedestrian ways, or urban trails shall be installed to provide continuity between noncontinuous systems of sidewalks, pedestrian ways or urban trails already installed or provided for in the same subdivision or adjacent subdivisions. In any situation where the public interest or a potential safety hazard exists, the hearing examiner may recommend sidewalks be installed.

C. Alternatives. Off-street walkway systems and urban trails may be considered by the hearing examiner in lieu of sidewalks required by this section. Easements may be required for pedestrian ways along watercourses or other suitable areas necessary for the implementation of major trail systems.

D. Minimum Widths and Locations. The minimum sidewalk and trail widths and locations shall be as set forth in EMC 12.18.057. (Ord. 2607 § 1 (Exh. A), 2017; Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.150 Installation of utilities.

After grading is completed and approved and before any base is applied all of the underground utilities and all service connections shall be installed, completed and approved throughout the length of the road and across the flat section according to city standards. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.160 Street lighting.

Each subdivision shall provide circuitry and street lighting located in accordance with city standards. Street light spacing shall take existing trees into consideration. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.170 Underground utilities.

All utilities designed to serve the subdivision shall be placed underground. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.180 Sanitary sewers.

All lots, blocks and parcels in a subdivision shall be served by a city sanitary sewer. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.190 Stormwater management.

Stormwater facilities shall be provided for stormwater management in accordance with Chapter 14.10 EMC. (Ord. 2607 § 1 (Exh. A), 2017; Ord. 2316 § 2 (Exh. A), 2006).

17.16.200 Water system.

The water distribution system, including fire hydrants, shall be designed and installed in accordance with city standards and the requirements of the fire department. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.210 Easements for utilities.

Easements may be required for the maintenance and operation of utilities. Easements may be required along the lines of lots or through blocks where necessary for the extension of existing or planned utilities. Easements along lot lines shall be at least 10 feet wide. Such easements will have written approval of utilities companies or other interested agencies prior to acceptance of the final plat. (Ord. 2316 § 2 (Exh. A), 2006).

17.16.220 Blocks.

A. Width. Blocks shall be wide enough to allow two tiers of lots, except where fronting on arterials or prevented by topographical conditions or size of the property.

B. Length. The minimum length of a block adjacent to and parallel to a minor arterial should be 600 feet. All residential blocks shall not be less than 300 feet nor more than 1,320 feet in length. In blocks over 660 feet in length, the hearing examiner may recommend an urban trail of not less than 10 feet in width dedicated to the public to extend entirely across the block and at locations deemed necessary by the public works department. The urban trail shall be paved for the entire width and length with a permanent surface and shall be adequately lighted. Fences shall be provided along both sides of the urban trail and shall be located on private property. (Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.230 Lots.

A. Required. Lots are required in residential subdivisions only when a block is intended to be sold into more than one ownership. Lots are optional in commercial and industrial subdivisions. The size, shape and orientation of lots shall meet the minimum area and width requirements of the applicable zoning classification and shall be appropriate for the type of development and use contemplated. However, if lots for individual sale or lease are created, they shall conform to the following criteria:

1. The size, shape and orientation of the lot shall be appropriate for the location of the proposed subdivision and for the type of development contemplated.

2. Excessive depth in relation to width should be avoided. A desirable proportion of depth to width shall be two to one.

3. Every lot shall abut a public or private street.

4. Width of lots shall conform to the requirements of the zoning ordinance or 50 feet where no width is given.

5. Lots, except corner lots, having frontage on two streets should be avoided.

6. Side lot lines should be at right angles to the right-of-way line of the street on which the lot faces, whenever possible.

7. Corner lots for residential use shall be platted wider than interior lots to provide the front yard requirements on the side street as prescribed by the zoning ordinance.

8. No more than two panhandle accesses shall be permitted side-by-side in a subdivision.

9. Lots shall comply with the underlying zone.

10. Lots adjacent to a minor arterial should be laid out so as to provide access to streets other than arterials and a waiver of direct access shall be required as a condition of approval. If the developer presents proof that direct vehicular access to such lots is necessary to development of his property, the hearing examiner may permit direct access. The hearing examiner may require reasonable conditions to minimize potential hazards to public safety.

B. Substandard Area Lots. In residential plats with 10 or more single-family lots, a maximum of 10 percent of the total number of lots in the plat may contain less lot areas than allowed by the underlying zone which shall not be less than 90 percent of the required minimum area; provided the mean average of all the lots in the plat shall be equal to or greater than the minimum lot area of the underlying zone; further provided, that the area used in the calculation of the substandard lots shall be not less than 90 percent of the minimum required lot area. Lots smaller than allowed by the underlying zone shall be dispersed as evenly as possible throughout the plat to avoid a concentration of such lots in any one area. If this option is employed, a copy of the above required calculations shall be submitted with the plat application. (Ord. 2400 § 1, 2008; Ord. 2316 § 2 (Exh. A), 2006).

17.16.240 Flooding and geological hazard.

If any portion of the land within the boundary of a preliminary plat or approved record or survey is subject to flooding or inundation, that portion of the subdivision shall have the approval of the state according to Chapter 86.16 RCW before the administrator and the planning commission shall consider the subdivision. If any portion of a preliminary plat is subject to flooding, inundation or geological hazard and the probable use of the property will require structures, the planning commission shall disapprove the preliminary plat or that portion of the subdivision so affected. Protective improvements may be constructed as a conditional precedent to approval of the preliminary and/or final plat. The administrator may require the subdivider to submit a geologist’s report if there is concern about geological hazards and a soil engineer’s report shall be required for plats with slopes of 15 percent or greater. (Ord. 2316 § 2 (Exh. A), 2006).