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Sign Posted On Site
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Public Noticing
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Signed Affidavit
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Resolved
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Public Noticing
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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STORMWATER/ EROSION CONTROL:
• Stormwater design shall be in accordance with PMC Chapter 21.10 and the Department of Ecology (Ecology) Stormwater Management Manual for Western Washington (aka “Ecology Manual”) as adopted by the City Council at the time of project application. The City will be adopting the 2019 Ecology Manual July 1, 2022. Since a Preliminary Site Plan application is not a vesting tool, the proposed stormwater design shall be in accordance with the 2019 Ecology Manual.
• Refer to City Standards, Section 200 for Stormwater System Requirements. [PMC 17.42]
• The applicant shall complete the stormwater flowchart, Figure 3.1, contained in Ecology’s Phase II Municipal Stormwater Permit, Appendix I. The completed flowchart shall be submitted with the preliminary stormwater site plan and highlight the Minimum Requirements (MR) triggered by the project thresholds. The link below may be used to obtain the flowchart:
Western Washington PH II Stormwater Permit
• NOTE: Areas of disturbance within the public ROW must be included in the project area as part of the stormwater thresholds and calculations.
• Public right-of-way runoff shall be detained and treated independently from proposed private stormwater facilities. This shall be accomplished by enlarging the private facilities to account for bypass runoff; providing separate publicly maintained storm facilities within a tract or dedicated right-of-way; or, other methods as approved by the City Engineer. [PMC 21.10.190(3)]
• Development and redevelopment projects are required to employ, wherever feasible, Low Impact Development (LID) Best Management Practices (BMPs) to meet the design criteria set forth in PMC 21.10.190, the Ecology Manual Volume I, Minimum Requirement 5; Volume III, Chapter 3; and Volume V, Chapter 5. Please see additional comments at the end of this section associated with the submitted preliminary storm report.
• If infiltration facilities/BMPs are anticipated, the number of infiltration tests shall be based on the area contributing to the proposed facility/BMP, e.g., one test for every 5,000 sq. ft of permeable pavement, or one test for each bioretention cell.
• Preliminary feasibility/infeasibility testing for infiltration facilities/BMPs shall be in accordance with the site analysis requirements of the Ecology Manual, Volume I, Chapter 3, specifically:
- Groundwater evaluation, either instantaneous (MR1-5), or continuous monitoring (MR1-9), during the wet weather months (December 21 through April 1).
- Hydraulic conductivity testing:
i. If the development meets the threshold to require implementation of Minimum Requirement #7 (flow control); or, if the site soils are consolidated; or, if the property is encumbered by a critical area, then Small Scale Pilot Infiltration Testing (PIT) during the wet weather months (December 21 through April 1) is required.
ii. If the development does not meet the threshold to require implementation of Minimum Requirement #7; or, is not encumbered by a critical area; and is located on soils unconsolidated by glacial advance, grain size analyses may be substituted for the Small Scale PIT test at the discretion of the review engineer.
- Testing to determine the hydraulic restriction layer.
- Mounding analysis may be required in accordance with Ecology Volume III Section 3.3.8.
• Upon submission of the geotechnical infiltration testing, appropriate long-term correction factors shall be noted for any areas utilizing infiltration into the underlying native soils in accordance with the Ecology Manual, Volume III, Chapter 3. Provide the long-term infiltration rate calculation in the stormwater report.
• At the time of civil permit application, the applicant is responsible for submitting a permanent storm water management plan which meets the design requirements provided by PMC Section 21.10. [PMC 21.10.190, 21.10.060]
- When using WWHM for analysis, provide the following WWHM project files with the civil permit application:
- Binary project file (WHM file extension)
- ASCII project file (WH2 file extension)
- WDM file (WDM file extension)
- WWHM report text (Word file)
• Each section of the TIR/SSP shall be individually indexed and tabbed with each permit application and every re-submittal prior to review by the City. [PMC 21.10.060]
• Overflow facilities shall be provided for any proposed detention/retention (R/D) facilities in accordance with the City Standards. This includes a downstream analysis a minimum of ¼ mile downstream from the site.
• Any above-ground stormwater facility shall be screened from public right-of-way and adjacent property per the underlying zoning perimeter buffer requirements in the PMC.
• Stormwater R/D facilities shall be a minimum of 20-feet from any public right-of-way, tract, vegetative buffer, and/or property line measured from the toe of the exterior slope/embankment/exterior face of the facility. [PMC 21.10 & DOE Manual, Vol. V, Pg 10-39 and Pg 10-9]
• A minimum of 5-feet clearance shall be provided from the toe of any exterior slope/embankment to any tract, property line, fence, or any required vegetative buffer. [PMC 21.10 & CS 206]
• The 2-yr, 10-yr, and 100-yr water surface elevation (WSE) shall be shown on the R/D facility cross-section(s).
• Water quality treatment of stormwater shall be in accordance with the Ecology Manual, Volume 1, Minimum Requirement 6; and Volume 5, Runoff Treatment.
• If the applicant proposes to use bioretention cells for water quality treatment, the following notes shall be added to the civil design plans:
- “At the completion of the bioretention cells construction, the engineer-of-record shall provide a written statement to the City of Puyallup that the bioretention cells were built per the approved design.”
- “The bioretention soil media (BSM) supplier shall certify in writing that the bioretention soil media meets the guidelines for Ecology-approved BSM including mineral aggregate gradation, compost guidelines, and mix standards as specified in the 2012 Low Impact Development Technical Guidance Manual for Puget Sound. And, if so verified, no laboratory infiltration testing, cation exchange, or organic content testing is required.”
• Trench dams shall be provided at the property line for utilities located below infiltrative facilities including, but not limited to, permeable pavements and bioretention facilities. Reference City Standard Detail 06.01.10.
• Overflow facilities shall be provided at the low points of any proposed permeable pavement areas to allow safe discharge to the downstream public storm system.
• Construction of frontage improvements associated with this project will require either extension of the stormwater main or new storm crossings to accommodate road runoff.
• At the time of civil permit application, all pipe reaches shall be summarized in a Conveyance Table containing the following minimum information and included in the TIR:
Pipe Reach Name Design Flow (cfs)
Structure Tributary Area Pipe-Full Flow (cfs)
Pipe Diameter (in) Water Depth at Design Flow (in)
Pipe Length (ft) Critical Depth (in)
Pipe Slope (%) Velocity at Design Flow (fps)
Manning’s Coefficient (n) Velocity at Pipe-Full Flow (fps)
Percent full at Design Flow (%)
HGL for each Pipe Reach (elev)
• At the time of civil permit application, the applicant shall provide a conveyance capacity analysis of the existing 27th Ave SE storm system between the project site and Meridian to ensure adequate capacity assuming existing conditions for any contributing offsite areas, and developed conditions for the project site.
• All storm drains shall be signed as follows:
a) Publicly maintained stormwater catch basins shall be signed using glue-down markers supplied by the City and installed by the project proponent.
b) Privately maintained stormwater catch basins shall be signed with pre-cut 90ml torch down heavy-duty, intersection-grade preformed thermoplastic pavement marking material. It shall read either “Only Rain Down the Drain" or “No Dumping, Drains to Stream”. Alternatively, the glue-down markers may be purchased from the City for a nominal fee.
• All private storm drainage facilities shall be covered by a maintenance agreement provided by the City and recorded with Pierce County. Under this agreement, if the owner fails to properly maintain the facilities, the City, after giving the owner notice, may perform necessary maintenance at the owner’s expense.
• Erosion control measures for this site will be critical. A comprehensive erosion control plan will be required as part of the civil permit application.
• A Stormwater Systems Development fee will be assessed for each new equivalent service unit (ESU) in accordance with PMC Chapter 14.26. Each ESU is equal to 2,800 square feet of ‘hard’ surface. The current SDC as of this writing is $3,560.00 per ESU.
• Stormwater Systems Development fees are due at the time of site development permit or in the case where no site development permit is required, at the time of building permit issuance for the individual lot(s); and the fees do not vest until the time of site development permit issuance, or at the time of building permit issuance in the case where a site development permit is not required.
• A Construction Stormwater General Permit shall be obtained from the Department of Ecology if any land disturbing activities such as clearing, grading, excavating and/or demolition will disturb one or more acres of land, or are part of larger common plan of development or sale that will ultimately disturb one or more acres of land. The link below may be used to obtain information to apply for this permit:
Construction Stormwater General Permit
• The following comments are associated with the March 29, 2022 preliminary stormwater report. The applicant is not required to respond to these comments at this time and Engineering is satisfied that appropriate documentation has been provided to allow the project to move forward to the public hearing. However, these comments must be thoroughly addressed at time of civil permit application:
- The applicant has proposed a stormwater detention facility to serve the project which is a conservative assumption in terms of the viability of the overall project. However, the City still has reservations that the feasibility/infeasibility criteria for implementing Minimum Requirement 5 (MR5) BMPs has been adequately addressed.
- Specifically, the geotechnical report dated February 10, 2022 indicates that the site consists of both recessional outwash and recessional glaciolacustrine soils with the majority of the site consisting of the outwash soils, yet only one small-scale PIT test was conducted in an area of the site where 97% of the soil particles pass the #200 sieve. Additional infiltration testing or additional clarification is needed to justify a determination of BMP infeasibility for the central and eastern portions of the project site.
- There may be other BMP infeasibility criteria available to the applicant outlined in the Ecology Manual. For example, downstream impacts associated with lateral flow or potential erosion hazards due to infiltrated stormwater, but the current application materials do not appear sufficient to support a definitive project-wide infeasibility determination for the BMPs listed in Minimum Requirement 5.
- For offsite basin inflow and onsite unconverted vegetation areas: document compliance with 2019 Ecology Manual, Vol III, Sec III-2.4 (2014 Manual, Vol. III, Appendix III-B, Section 6).
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Submit With Civil Permit Application
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Miscellaneous Condition
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Resolved
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Submit With Civil Permit Application
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Miscellaneous Condition
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Resolved
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Submit With Civil Permit Application
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Condition
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Resolved
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Standard Conditions
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Miscellaneous Planning Condition
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Resolved
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Submit With Civil Permit Application
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Final Landscape Plan - Tree Protection
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Resolved
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Submit With Civil Permit Application
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Miscellaneous SEPA Condition
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Resolved
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SEPA Condition
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Miscellaneous Condition
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Resolved
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Submit With Civil Permit Application
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