Chapter 12.55
CONSTRUCTION PLANS
Sections:
12.55.010 General requirements.
12.55.030 When plans are not required.
12.55.040 Submittal procedure.
12.55.060 General standards for subdivision final construction plans.
12.55.010 General requirements.
All construction plans and drainage reports, soils reports and pavement designs shall be prepared by, or under the direction of, an engineer, and shall be reviewed for the minimum requirements set forth herein. The engineer should be aware that whenever unusual or serious problems are anticipated in conjunction with a proposed construction project, additional information and analysis beyond the minimum requirements of these specifications and criteria will be required. In all cases, the engineer shall comply with all local, state and federal regulations applicable to the project. (Ord. TLS 11-02-02B Exh. B (part): Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))
12.55.020 Certification.
A. Construction plans submitted for review and comment shall be prepared by an engineer. The plans must include the following statement on the cover sheet:
These construction plans for (name of subdivision, development, or project) were prepared by me (or under my direct supervision) in accordance with the requirements of the Douglas County Road Standards.
Name of Engineer
Name of Firm
Date
The statement shall be signed and stamped by the registered professional engineer who prepared or directed preparation of the construction plans.
B. Unless otherwise identified or noted, all construction plan submittals are assumed to comply with the provisions of this manual. Alternatives to these standards may be requested as set forth in DCC Chapter 12.50. Failure to follow prescribed procedures may result in return of submittals, additional review fees, or both.
C. Douglas County shall not be responsible for the accuracy and adequacy of the design or dimensions and elevations on the plans. Douglas County, through the acceptance of the construction plan or drainage report and other supporting documents, assumes no responsibility for the completeness and/or accuracy of the construction plan or drainage report. The cover sheet shall bear the following statement:
The engineer who has prepared these plans by execution and/or seal hereof does hereby affirm responsibility to the county, as a beneficiary of said engineer’s work, for any errors and omissions contained in these plans, and approval of these plans by the county engineer shall not relieve the engineer who has prepared these plans of any such responsibility.
D. The plans, reports, basin maps and calculations shall be signed, sealed and dated by the applicant’s engineer. The cover sheet of the plan set and the cover sheet of all calculations shall bear the certification by the applicant’s engineer that reads:
The design improvements shown in this set of plans and calculations conform to the current edition of the Douglas County Road Standards. All design variances have been approved by the Douglas County engineer. I approve these plans for construction.
(Ord. TLS 11-02-02B Exh. B (part); Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))
12.55.030 When plans are not required.
Subject to review, the county may waive plan requirements, wholly or in part, based upon the following criteria:
For improvement to existing public roads if each of the following requirements are met:
A. No more than five thousand square feet will be cleared and graded within the right-of-way or easement; and
B. The existing road grade does not exceed ten percent; and
C. The existing road has a uniform cross-section; and
D. The work does not intercept a stream or wetland or otherwise impact natural surface drainage as set in the county code regarding critical areas, shorelines and surface water; and
E. Plans do not include a retention/detention facility within the right-of-way; and
F. Douglas County standard drawings, submitted with required permits, are sufficient to describe the improvement to be constructed. (Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))
12.55.040 Submittal procedure.
Plans for proposed road and drainage construction shall be submitted to the department of transportation and land services as follows:
A. The first submittal shall consist of three complete sets of prints together with drainage calculations and other necessary supporting information, and shall be signed and stamped by the applicant’s engineer. The applicant’s engineer must be a registered engineer in the state of Washington. Review fees, when applicable, shall be paid by the applicant before review of the plans by the county commences.
B. If corrections are required, the county will return a redlined print showing necessary corrections. When corrections are required, the applicant’s engineer shall return the redlined print with the corrected plans. Plans and reports submitted later than one year from the date that the county redlines are returned to the applicant or applicant’s engineer shall be subject to additional hourly review fees in accordance with the Douglas County fee schedule.
C. Subsequent submittals shall also contain three complete sets of plans and other supporting information, if corrected. When all corrections have been made to the county engineer’s satisfaction, the original Mylar set of plans will be signed and returned to the applicant’s engineer. The final plans will require stamping and signature of the applicant’s engineer.
D. The applicant’s engineer shall provide the county with a good quality reproducible Mylar with the applicant’s registration stamp and signature plus two complete sets of prints of the approved plans and one complete set of other supporting documentation. Where plans are prepared in an electronic format such as AutoCad or another format acceptable by the county, the applicant’s engineer shall also provide copies of the electronic data files to the county. The applicant’s engineer shall also provide a quantity take-off and engineer’s cost estimate of proposed construction when the project is to be secured by some form of performance guarantee.
E. Plans will be reviewed by the county according to the date they were submitted. Previously reviewed or approved plans submitted to the county for a revision will be considered a new submittal. Approved plans under construction will be considered a resubmittal and will be reviewed prior to new submittals. (Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))
12.55.050 Plan elements.
The following plan elements shall be provided on all construction plans:
A. Vicinity Map. Minimum scale is one inch equals one thousand feet showing the location and name of all arterial roadways within one mile of the proposed construction, and all other roadways in the vicinity of the proposed construction. Shading shall indicate the project area. This map is required on the cover sheet or first sheet of all submittals, if no cover sheet has been used. The vicinity map shall show all arterial roadways and major drainageways. Section, township, and range shall also be shown.
The minimum size of the vicinity map shall be ten inches by ten inches.
B. Title Block. A title block is required on every sheet and cover sheet submitted for review and acceptance. The subdivision name and filing number; planned development name (if applicable); the type of improvement; name, address, including zip code, and telephone number and name of the consulting engineer; name, address, including zip code, telephone number and name of the contact person at the developer; and sheet number (consecutive, beginning with the cover sheet) shall be included in the title block. The title block shall be located in the extreme lower right hand corner, the right side margin, or along the bottom edge of the sheet.
The title block must also have sufficient space to show the nature, date and approval of all revisions.
The original date of the plans and any subsequent revisions must be shown in the title block.
C. Acceptance Block.
1. All roadway construction plans, storm sewer or other drainage improvement construction plans, and privately or publicly maintained stormwater detention or retention facility construction plans must show the acceptance signature of the designated representative of the county engineer. Where there are existing utilities within the right-of-way, an additional acceptance block for each utility shall be included.
2. Plans for traffic control during construction must be accepted prior to issuing construction permits.
3. Plans for construction stormwater pollution prevention must be accepted prior to issuing construction permits.
4. Signing/striping plans require acceptance prior to issuing construction permits.
5. The acceptance block shall be located in the lower right-hand quadrant of the cover sheet.
6. Acceptance block shall be as follows:
These plans have been reviewed by Douglas County Department of Transportation and Land Services and have been accepted for complying with the requirements of Douglas County Road Standards. These plans are valid for three years from the date of acceptance.
___________________ _________
County Engineer Date
D. Scale. The following scales are the minimum required. More detailed scales will be required where necessary to clearly show details.
1. Plan and profile plans: horizontal one inch equals fifty feet, vertical one inch equal five feet.
2. Master, preliminary, and final drainage plans; site plans, etc.: from one inch equals fifty feet to one inch equals one hundred feet.
E. Seal/Signature. The seal and signature of the owner’s engineer, under whose supervision the plans were prepared, shall be located next to the acceptance block on each sheet.
F. Utilities. The type, size, location and number of all aboveground and underground utilities shall be shown. Field-verified elevations and locations may be required on the construction plans for all underground utilities which will potentially affect the design or construction. It will be the responsibility of the contractor to verify the existence and location of all underground utilities along their route of work prior to commencing any new construction. Field-located utilities not shown on accepted construction plans shall be added to the record (as-built) drawings submitted as a condition of conditional acceptance of the public.
G. Private Improvements.
1. Private improvements such as roadways, driveways, utilities, etc., shall be clearly shown and labeled as such on each sheet of the construction plans. The note below shall appear on the cover sheet of the construction plans for private improvements:
Douglas County shall not be responsible for the maintenance of roadway and appurtenant improvements, including storm drainage structures and pipes, for the following private roads: (list).
2. When a request is made for the county to assume maintenance of any private improvement, it shall be the responsibility of the person(s) making the request to satisfactorily demonstrate that the private improvement is in fact constructed in accordance with the current Douglas County roadway standards for county roads. In addition, all necessary right-of-way must be transferred to the county and the road established by the board of county commissioners as per RCW.
3. Douglas County will not accept maintenance responsibilities for private road improvements associated with land development activities. In no case shall private improvements not constructed in accordance with the applicable design and construction standards and specifications be accepted for maintenance by Douglas County.
H. Road Plan, Profile Elements and Details. In addition to the requirements set forth elsewhere in these standards, the following information shall be shown on all roadway plans submitted for review and approval.
1. Plan View. The plan view shall include, but not be limited to, the following:
a. Existing and proposed property and/or right-of-way lines, easements and/or tracts and/or irrigation ditch(es). Type and dimension of easement or tract is to be clearly labeled. Right-of-way lines with individual parcel or lot frontages are to be dimensioned.
b. Survey lines and stations shall normally be based on centerline of street; other profiles may be included but shall be referenced to centerline stationing.
c. Roadways and roadway names.
d. North arrow.
e. Roadway alignments with one-hundred-foot stationing, reading from west to east/south to north including stationing and dimensions of all roadway width variations from the typical roadway section(s).
f. All topographic features with right-of-way limits and sufficient area beyond to resolve questions of setback, slope, drainage, access onto abutting property, and road continuations. A minimum of one hundred feet shall be shown on either side of centerline and a minimum of two hundred feet shall be shown from the terminus of the road, or such additional terrain as directed by the county engineer.
g. Existing utilities and structures, including, but not limited to: storm sewer and appurtenances, fence lines and gates, water lines and appurtenances, irrigation, ditches or swales, electric lines and appurtenances, curbs and gutters, sewer lines and appurtenances, pavement limits, telephone lines and appurtenances, bridges or culverts, cable television lines and appurtenances, guardrails, signs, gas lines and appurtenances, etc.
h. Station and critical elevation (flow line, invert of pipe, etc.) of all existing and proposed utility or drainage structures. Location of utilities shall be dimensioned horizontally and vertically from roadway centerline profile grade.
i. Storm drainage flow direction arrows, particularly at intersections and all high and low points.
j. Match lines and consecutive sheet numbers, beginning with cover sheet.
k. Station and elevation of all horizontal curves including PI, PCs, PTs, etc.; high or low point and PI of all vertical curves, existing and proposed, centerline bearings, distances, and complete curve data including superelevation data and pivot point locations.
l. Curb return radii, existing and proposed, including stations and elevations of all curb returns; midpoint elevations, and flow line-flow line intersection elevations and grades.
m. Mid-block handicap ramp locations at tee intersections.
n. Centerline stations of all non-single-family residential driveways and all intersecting roadways.
o. Survey tie lines to section corners or quarter corners, consistent with that shown on the plat.
p. Typical roadway cross-section for all roadways, existing or proposed, within and adjacent to the proposed development. These cross-sections shall appear on the detail sheet or if no detail sheet has been used, the first sheet of the submittal showing roadway design. They shall indicate type of roadway(s), profile grade design point (centerline, flow line, top of curb, lip of gutter, etc.), roadway width, right-of-way, type of curb, gutter and walk, pavement cross slope, pavement thickness, and structural material components of the pavement, base and sub-base, together with specifications for treatment of subgrade and installation of pavement structural members.
q. Construction plans for arterial improvements. Any roadway intersecting an arterial, or any collector intersection requiring signalized traffic control shall include construction and lane details for the new construction and existing facilities a minimum of one hundred fifty feet beyond the limits of construction.
2. Profile. The profile shall include, but not be limited to, the following:
a. Original ground (dashed) and design grade (heavy, solid). Both grades are to be plainly labeled.
b. All design elevations shall be centerline, top of curb, lip of gutter, or flow line (preferred) for six-inch vertical curb and gutter; or back of walk, or lip of gutter, or flow line (preferred) for combination curb, gutter and walk. The basis of record drawing information shall be the same as the design (both flow line or both top of curb, etc.). Ditch profiles may be required for rural road sections at the discretion of the county engineer.
c. Stationing continuous for the entire portion of the roadway shown in the plan view, with the centerline station of all non-single-family driveways and all intersecting roadways clearly labeled.
d. All existing curbs, gutters, sidewalks and pavement adjacent to the proposed design. Basis for existing grades shall be as-built elevations at intervals not to exceed twenty-five feet. Previously approved designs are not an acceptable means of establishing existing grades.
e. Existing and New Utilities. Elevation and location of all utilities in the immediate vicinity of the construction shall be shown on the plans.
f. Station and elevation of all vertical grade breaks, existing (as-built) and proposed.
g. Distance and grade between VPIs.
h. Vertical curves, when necessary, with VPI, VPC, and VPT, high or low point (if applicable) stations and elevations. All vertical curves shall be labeled with length of curve (L) and K=L/A where A is the algebraic difference in slopes, in percent.
i. Superelevation data including pivot point locations shall be required and included for all roadways with a design speed of thirty miles per hour or higher.
j. Profiles for all curb returns (except medians).
3. Details. All details necessary for a complete set of plans that are not covered by reference to the WSDOT Standard Plans such as walls, special drainage elements, major culverts, etc., shall be included in the plans.
4. Standard Plans. The submitted plans shall include copies of all WSDOT Standard Plans referenced within the plans.
I. Temporary Erosion Control Plan. A temporary erosion/sedimentation control plan, showing the location and control measures intended to minimize the effects of erosion and siltation due to construction operations shall be submitted with the construction plans and shall conform to the requirements of the WSDOT Standard Specifications and the Stormwater Management Manual for Eastern Washington.
J. Notes. In addition to other notes required in these standards, the following notes shall appear on the cover sheet of all submittals containing roadway plans:
Standard Plan Notes
1. All materials and workmanship shall be in accordance with the requirements of the most current edition of the state of Washington Department of Transportation Standard Specifications for Road and Bridge Construction and Douglas County Road Standards.
2. Catch basins shall be Type 1 or Type 2, WSDOT Standard Plans, with standard, vaned or herringbone frame and grate unless otherwise noted. The outside edge of the catch basin shall be placed at the intersection of the curb and gutter and 0.010 feet to 0.015 feet below finished grade, or in the gutter line of the rolled edge section.
3. If adequate inspection is not completed and documented before completion of the roadway construction, it may be necessary for core drilling and testing to be performed to assure an acceptable quality of roadway. When core drilling is found to be necessary, the applicant will be held responsible for all costs incurred.
4. It will be the applicant’s responsibility to contact all utility companies in order to assure that all lines, pipes, poles and other appurtenances are properly located and their installation is coordinated with the road construction. All utility relocation work shall be at the expense of the applicant and must be in accordance with Douglas County Road Standards prior to road acceptance.
5. Culvert pipe shall be galvanized steel or plastic (ADS smooth wall) twelve-inch diameter minimum pipe with beveled ends unless otherwise noted. Beveled ends shall match the in-slope in the ditch line or match the slope in a cut or fill section.
6. Buried utilities are shown in their approximate location. The applicant shall have the utilities verified on the ground prior to any construction.
7. On-site erosion control measures shall be the responsibility of the applicant and be in place prior to construction. Any problems occurring before final acceptance by Douglas County and within eighteen months thereafter shall be corrected by the applicant. At the end of the eighteen-month period, or as otherwise directed by the county engineer, the applicant shall remove all temporary, nondegradable erosion control measures.
8. In accordance with the Department of Ecology Air Quality Standards, the applicant shall be responsible for controlling all fugitive dust that may be generated by the construction project.
9. Any revisions to plans must be made by the applicant’s engineer and approved by the county engineer prior to any implementation in the field.
10. All pavement markings shall conform to the requirements of the MUTCD.
11. Before striping takes place, the applicant shall contact the Douglas County Transportation and Land Services office for coordination of the striping.
12. A copy of the approved plans must be on the job site whenever construction is in progress.
13. Slopes shall be stabilized to prevent erosion. In case erosion occurs in ditches, ditch lining is to be provided as requested and specified by the county.
14. Where newly constructed paving meets existing paving, the applicant shall saw cut and overlay and feather new pavement to provide a smooth transition from existing to proposed paving. Application of a thin tack coat of emulsified asphalt shall be applied to ensure proper bonding.
15. The completed surface of all courses shall be of uniform texture, smooth, uniform as to crown and grade, and free from defects of all kinds. The completed surface of the wearing course shall not vary more than one-eighth-inch from the lower edge of a ten-foot straightedge placed on the surface parallel to the centerline. The transverse slope of the completed surface of the wearing course shall vary not more than one-quarter-inch in ten feet from the rate of transverse slope shown on the plans.
16. Materials sampling and testing shall be at a frequency and magnitude as specified in the standard specifications or determined by the county engineer. A private and independent testing laboratory shall perform testing and sampling. Certified test reports shall be furnished for all tests performed by private testing laboratories.
K. Signing and Striping Plan. Permanent signage and striping shall be complete and in place before any new roadway is opened to the public. Traffic signal installation and equipment shall conform to the Washington Department of Transportation Standards and Specifications. The Manual on Uniform Traffic Control Devices Signal Warrants shall be met for signal installation. All subdivisions, road improvement projects, and/or commercial development must incorporate a separate signage and striping plan in accordance with the following criteria:
1. Submittal. Separate signage and striping plans are to consist of an overall area map noting all specific use areas, such as schools, parks, recreation centers, library, commercial, industrial, etc. The pages following the area map are to be broken down into road segments, for notation of signage and striping details.
2. Sign Warrants. Traffic control devices which are not warranted by MUTCD shall not be installed. When MUTCD guidelines are not applicable for a given case, a traffic engineering study by the owner’s engineer will be required. This study will address the existing conditions, safety issues, and the applicable warrants.
L. Monuments and Benchmarks. See DCC Section 12.57.040, Survey monuments. (Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))
12.55.060 General standards for subdivision final construction plans.
The following general standards shall be met for final construction plans:
A. All road and storm sewer construction must conform to the Douglas County road and stormwater standards current at the time of plan approval.
B. All traffic control devices must conform to the Manual on Uniform Traffic Control Devices.
C. Prior to release of collateral by Douglas County, the developer must present a statement from an engineer registered as a professional engineer in the state of Washington that the project has been completed in substantial compliance with approved plans and specifications and documenting that the engineer has made regular on-site inspections during the course of construction, and the field plans utilized were the same as those approved by Douglas County. The engineer shall also state that quality control testing has been undertaken for the project, which testing demonstrates compliance with the plans and specifications approved by Douglas County. The developer must also submit the following items prior to release of collateral:
1. As-built plans for the improvements must be submitted at the time the letter requesting collateral release is submitted. The as-built plans must be clearly labeled as such, and must be signed and dated by a registered professional engineer. They must show any deviations from the approved plans. Release of collateral will not occur if the county engineer determines deviations are present which have not received prior approval.
2. A letter or letters of acceptance and responsibility for maintenance of the improvements by the appropriate utility company, special district, or town for all utilities and roads.
3. A letter from the appropriate fire authority stating that fire hydrants, where required, are in place in accordance with the approved plans. The letter shall also state that the fire hydrants are operational and, if required by the fire marshal, provide the results of fire flow tests.
4. For roads under consideration for adoption to the county road system: Quality control test results must be submitted for all phases of the project in accordance with Washington State Department of Transportation’s schedule for minimum materials sampling, testing, and inspection as found in the WSDOT Materials Manual. The county engineer shall review and approve a proposed schedule of testing before commencement of construction. (Ord. TLS 09-11-49E (Exh. B) (part): Ord. TLS 04-02-30B Exh. A (part))