Chapter 16.28
IMPROVEMENTS
Sections:
16.28.070 Street signs and traffic control.
16.28.090 Irrigation facilities.
16.28.010 Streets.
Existing or proposed streets within or adjacent to a proposed subdivision shall be improved at the expense of the developer by the construction of curbs, gutters, sidewalks, illumination, storm drainage and pavement surface in conformance with the city’s design and construction standards and specifications for public works improvements. Improvement of adjacent streets to the proposed subdivision may be postponed by the city council until such time as other portions of this adjacent street are improved by the city or others. If such postponement of street improvements is permitted by the city council, an obligation or covenant running with the land shall be placed on the face of the subdivision plat which requires said lots in that subdivision to such adjacent street to participate in a future local improvement district for street improvements in compliance with Chapters 16.24 and 16.28 GMC as they exist at the time the local improvement district is formed. Postponement does not relieve the developer from his obligation to make the improvements at such time as is determined by the city council. The city council may require the developer to deposit all or a portion of the estimated development costs in escrow to cover the cost of the improvements postponed. (Ord. 2015-6 § 1; Ord. 1574 § 1, 2000; Ord. 1343 § 4, 1992).
16.28.020 Utilities.
A. All underground utilities (non-city-owned) in all new residential areas shall be installed and maintained at a depth of not less than three feet below the graded surface of said way or street, provided existing installations may be maintained at the present level until replaced.
B. All new or existing utilities within or adjacent to a proposed subdivision shall be installed underground, except for the following:
1. Electric, pad-mounted transformers;
2. Electric transmission systems of a voltage of 15 KV or more;
3. Service meters at structures;
4. TV cable amplifiers, distribution taps;
5. Telephone pedestals and cross-connection terminals;
6. Temporary services necessary for construction.
C. No buildings or structures, except fences, shall be permitted to be constructed on any utility easements, or over any utility facilities. Masonry fences will be considered as structures, rather than fences. (Ord. 2015-6 § 1; Ord. 1724 § 1, 2005; Ord. 1343 § 4, 1992).
16.28.030 Water.
A. A complete domestic water distribution and fire protection system shall be installed at the expense of the developer in conformance with the city’s approved water system plan. All water lines and services shall be installed prior to street improvements.
B. The water distribution system shall be designed and constructed in accordance with the State Department of Health regulations, the city’s design and construction standards and specifications for public works improvements, and with the standard practices of the city. Fire hydrants shall be installed, at the expense of the developer, at locations determined necessary by the fire chief. Water mains shall be extended to the far edge of subdivisions for future extension by others.
C. The city, at its discretion, may direct that water main diameters in excess of that needed for service and fire protection for the subdivision be installed. If the city directs such oversizing, the city will pay the difference in pipe material cost between the pipe diameter required for the subdivision and the city-directed oversize diameter pipe. (Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).
16.28.040 Sanitary sewer.
A. A sanitary sewer system shall be installed at the expense of the developer with a separate connection to the city sewer system for each lot and shall be constructed in conformance with the Comprehensive Sewer Plan.
B. Sewer lines should be located within the paved portion of the street right-of-way, and must be a minimum of eight inches in diameter.
C. The sanitary sewer system shall be designed and constructed in accordance with the State Department of Ecology regulations, the city’s design and construction standards and specifications for public works improvements, and with the standard practices of the city. Sewer mains shall be extended to the far edge of subdivisions for future extensions by others.
D. The city, at its discretion, may direct that sewer main diameters in excess of that needed for service for the subdivision be installed. If the city directs such oversizing, the city will pay the difference in pipe material cost between the pipe diameter required for the subdivision and the city-directed oversize diameter pipe.
E. A city-approved backflow prevention device shall be installed at the expense of the developer on the side sewer extension for each lot. (Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).
16.28.050 Storm drainage.
Each subdivision shall provide a drainage system for the collection, control, and disposal of surface water runoff. All storm drainage improvements shall be planned, designed, permitted, constructed and maintained in accordance with the requirements of the latest edition of the Washington Department of Ecology (WDOE) Stormwater Management Manual for Eastern Washington (SWMMEW).
A. It is the intent of this section to adequately provide for suitable drainage provision in all short or long subdivisions. All subdivisions shall provide for drainage such that their development does not conflict with present drainage patterns, or create a drainage problem within itself or for its neighbors.
B. A drainage plan, where required, shall be designed by a professional engineer licensed in the state of Washington and submitted to the city for review and approval for any proposed land development that will increase the quantity of or in any way alter the drainage runoff occurring prior to development.
C. Design calculations for peak flow and peak volume storage requirements shall be based on a design storm frequency of 25 years. At the city’s discretion, if the facilities are critical to public health and safety, or significant property damage could occur, or the development is located in a drainage problem area, they shall be designed to successfully pass the 50-year or 100-year storm.
D. The plan shall provide for the on-site detention and/or retention, and disposal, of the total water intercepted and collected by the development and the areas (improved or unimproved) lying and draining presently to and through the proposed development for the design storm, unless other natural or manmade systems are available for use.
E. There exist several areas of subsurface drainage systems, known as drainage improvement districts or DIDs. These systems were designed and constructed specifically for the purpose of lowering the ground water tables sufficiently to promote agricultural development. It was never the intent of these systems to convey surface drainage. Over the years, the drainage demand on these systems has steadily increased to the point where almost all of the DIDs are experiencing overloaded conditions. Engineers shall not consider the use of any of these DIDs in their drainage plans.
F. Detention and/or retention of storm water runoff from any proposed land development shall be accomplished by storm water holding facilities, either open or closed. Storm water shall be introduced into permeable soils via an infiltration system in accordance with the SWMMEW, all remaining on site.
G. The drainage plan shall incorporate all calculations for the determination of the required size of the system. Said calculations shall be based on required criteria hereinafter stated and upon an analysis of estimated runoff from areas contributing runoff to those facilities. Peak flow analyses and storage volume quantities shall be done using methods presented in the SWMMEW. The assumption for the infiltration rate used will need to be verified by the developer by actual field testing in the case of infiltration systems. Collection systems shall be either gravity pipe systems, open channels, or a combination of the two.
H. The submitted drainage plan shall incorporate, among other data, a topographical map to clearly define:
1. The proposed development;
2. All areas, improved or unimproved, lying upstream and draining to and across the proposed development; and
3. Drainage course, natural or otherwise, to which the proposed development shall drain.
I. Said plans shall include a plan-profile of the systems, including cross-sections of all open ditches and channels. Hydraulic and physical data such as grades, bottom elevations of ditches and channels, inverts of pipes at all structures, such as manholes and catch basins, sizes and lengths of all pipes, length of ditches and channels, and top elevations of all catch basin covers shall be called out. This includes the invert elevations of the existing or other proposed storm drainage systems that the subject drainage plan proposes to tie into. (Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).
16.28.060 Sidewalks.
Cement concrete sidewalks shall be constructed at the developer’s expense along all new and existing streets in conformance with the following minimum standards:
A. Sidewalks shall be located in the right-of-way and shall be four inches thick in walk areas (behind barrier curb) and six inches thick in drivable areas (behind depressed and rolled curb);
B. Sidewalks shall be placed along at least one side of all local access streets and shall have a minimum width of five feet;
C. Sidewalks shall be placed along both sides of all arterial and collector streets and shall have a minimum width of six feet;
D. Where a proposed subdivision or short subdivision is located adjacent to an existing street, the subdivider is not required to provide a sidewalk on the opposite side of the street;
E. Curb ramps for physically handicapped shall be constructed pursuant to RCW 35.68.075 and 35.68.076 at all intersections and other appropriate locations. (Ord. 2015-6 § 1; Ord. 1406 § 3, 1995; Ord. 1343 § 4, 1992).
16.28.070 Street signs and traffic control.
The subdivider shall install, at his expense, street signs and traffic control devices to the satisfaction of the public works director. (Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).
16.28.080 Street lighting.
Street lights shall be installed with the capital cost at the developer’s expense in conformance with the following standards:
A. One street light at each intersection;
B. One street light at midblock if the block is longer than 450 feet; and
C. Placement of street lights along arterial and collector streets shall conform to the city’s design and construction standards and specifications for public works improvements.
Once the development is approved by the city as complete, the city shall assume ownership including financial and maintenance responsibilities for the street lights. (Ord. 2022-11 § 1; Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).
16.28.090 Irrigation facilities.
A. A pressurized irrigation piping system shall be installed at the expense of the developer within the subdivision boundaries with a separate three-fourths-inch minimum pipe diameter service lateral to each lot. The irrigation system shall be designed and constructed with the standard practices of the city.
B. Irrigation mains shall be four-inch diameter, pressure class 160 psi or greater, polyvinyl chloride (PVC) pipe installed and maintained at a depth of not less than two feet below the graded surface of streets or utility easements.
C. Individual irrigation service laterals shall be three-fourths-inch diameter, Schedule 40, polyvinyl chloride (PVC) pipe installed and maintained at a depth of not less than two feet below the graded surface of streets or utility easements.
D. Irrigation mains shall be extended to the far edge of subdivisions for future extension by others. (Ord. 2015-6 § 1; Ord. 1343 § 4, 1992).