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Title: Mitigation Payment System and Intersection Standards
Document Code No.: PUT 10-3-3 (PR)
Department/Issuing Agency: Department of Transportation, Road Services Division, CIP and Planning Section
Effective Date: November 4, 2001
Approved: /s/ Ron Sims
Type of Action: Superseding PUT 10-3-2 (PR) (PDF, 1.43 MB)

1.0 SUBJECT TITLE: Mitigation Payment System and Intersection Standards

1.1 EFFECTIVE DATE: November 4, 2001

1.2 TYPE OF ACTION: Superseding PUT 10-3-2 (PR)

1.3 KEY WORDS: Mitigation Payment System; Intersection Standards

2.0 PURPOSE: To establish standard procedures for the determination of impact fees and intersection improvements required of proposed developments (implementing King County Code Chapters 14.65, 14.75 and 14.80.)


3.1 Land owners

3.2 Development permit applicants

3.3 Department of Transportation; Road Services Division, CIP and Planning Section, Traffic Engineering Section, and the Transit Division;

3.4 Department of Development and Environmental Services


4.1 King County Charter, Section 850, Delegation of Authority.

4.2 King County Code, Section 14.65.025, Administrative rules – mitigation payment system, intersection standards.

4.3 Growth Management Act, RCW Chapter 36.70A and RCW Chapter 82.02.

4.4 State Environmental Policy Act and King County Code Chapter 20.44.

4.5 Countywide Planning Policies, King County Code Chapter 20.10.

4.6 King County Comprehensive Plan, King County Code Chapter 20.12.

4.7 King County Code Title 14, Roads and Bridges.

4.8 King County Code Chapter 2.98, Rules of County Agencies.

4.9 King County Administrative Policies and Procedures, INF 7-1-1(AEP).

5.0 DEFINITIONS:These definitions supplement the definitions contained in King County Code Chapters 14.65, 14.75 and 14.80.

5.01 "Adequate" means that transportation facilities provide for meeting or exceeding the County’s established level of service standards.

5.02 "Applicant" means a person, business, corporate entity, or agency that applies to the Department to pay an MPS fee or to participate in a SEPA traffic impact review of a proposed development.

5.03 "Calculated LOS" means a forecast level of service that includes existing traffic, ambient traffic growth, traffic that is expected to be generated by previously approved developments based on DDES records, and the traffic anticipated from the subject development and other proposed developments. The LOS is calculated for the horizon year of the development, unless otherwise required by the Director.

5.04 "Capacity" means a quantified estimate of the maximum number of vehicles that can be accommodated by a roadway section or intersection in the Committed Network during a peak travel period and under specified operating conditions. The calculation of capacity will be done according to the most recent edition of the Highway Capacity Manual (HCM), or by alternative methods approved by the Director. For traffic modeling purposes, the Section uses a look up table of link type capacities, based on the HCM and on link type characteristics.

5.05 "CIP" means the current adopted Capital Improvement Program.

5.06 "DDES" means the Department of Development and Environmental Services or its successor agency.

5.07 "Department" means the King County Department of Transportation.

5.08 "Development Approval" means the approval of an application for a development permit by the Department of Development and Environmental Services. The definition and usage does not apply here to a rezoning action or to an Urban Planned Development.

5.09 "Direct access" means the area in which a driveway or street serving as access to a development site intersects with a street immediately adjacent to the site.

5.10 "Direct traffic impact" means the volume of new trips from a development that, when added to the existing trips at a direct access or a directly serving access intersection, creates a warrant for safety or operational improvements at that intersection.

5.11 "Directly serving access" means any intersection within the immediate area of a development that is directly impacted by traffic generated by the development in route to or from the direct access.

5.12 "Director" means the Director of the King County Department of Transportation, or his designee.

5.13 "DOT" means the King County Department of Transportation or its successor agency.

5.14 "Examiner" means the King County Hearing Examiner.

5.15 "Financial Commitment" means revenue assured by the applicant or other parties shall be in a form acceptable to the Director.

5.16 "HCM" means the latest version of the "Highway Capacity Manual"

5.17 "IS" means Intersection Standards, as described in KCC 14.65.

5.18 "K.C.C." means the King County Code. References to the King County Code are to the King County Code as it now exists or is hereafter amended.

5.19 "LOS" means level of service for signalized or unsignalized intersections, which for Intersection Standards is described in the current Highway Capacity Manual. An alternate method of calculation may be used if approved by the Director.

5.20 "MUTCD" means the Manual of Uniform Traffic Control Devices issued by the United States Department of Transportation.

5.21 "Peak Period" means a composite one-hour afternoon period during which each roadway section carries its maximum volume of traffic. For the purposes of intersection analysis, the peak period may be morning or afternoon, depending on which time experiences the worst traffic conditions. In determining which period to analyze, both traffic volumes and turning movement volumes for specific intersections will be considered.

5.22 "Peak hour" means, for purposes of IS standards, the one hour period during which an intersection experiences its worst level of service. For the purposes of IS, the peak hour may be morning or afternoon, depending on which time experiences the worst traffic conditions. In determining which time period to analyze, both traffic volumes and turning movement volumes for specific intersections will be considered. The Director shall have the discretion to determine whether, for purposes of IS standards, intersection analyses are required for either or both AM and PM peak periods.

5.23 "Pooling project" means a road improvement project on the MPS list which has been selected to be funded (at least in part) by pooled MPS revenues from multiple developments. It has an adopted appropriation of funds needed to meet construction costs and a scheduled completion date. Each MPS zone has a unique list of projects which is impacted by the traffic to and from that zone, and which relates to the MPS impact fee for that zone based on project costs and proportional impacts. Each zone’s pooling projects are selected from that project list.

5.24 "Proportionate cost" means the amount of cost obligation for an intersection improvement to be shared by applicants and public agencies. It is calculated on the basis of the total trips being generated by their developments and the number of trips generated by each development.

5.25 "Reasonably related" as used in the MPS chapter of the ordinance means fair and equitable, and that the impact fee imposed on a development will be roughly proportional to the traffic impact of the development.

5.26 "Section" means the CIP and Transportation Planning Section of the King County Department of Transportation.

5.27 "SEPA" means the State Environmental Policy Act as implemented by King County in K.C.C. 20.44.

5.28 "Traffic Section" means the Traffic Engineering Section of the King County Department of Transportation.

5.29 "Transportation Strategies" means actions which reduce travel by single occupant vehicles predominantly in the peak morning and afternoon travel periods. Generally, strategies include actions to increase commuter travel by public transit and by high occupancy vehicles, and to reduce the need to travel in the peak periods. Such strategies are used to implement transportation demand management programs and commute trip reduction programs. Credit for trip reduction due to such strategies will be calculated on an individual basis.

5.30 "Urban Planned Development (UPD)" means a large-scale type of land development that is defined by DDES. Concurrency tests for UPDs only will be completed prior to the approval of the development permit application.

5.31 "Volume" means the number of vehicles passing a point on a road during a specified time. It is determined by field counts for existing volumes, or by the Section’s traffic model for future volumes. Other methods of determining future volumes must be approved by the Director.

5.32 "WSDOT" means the Washington State Department of Transportation.

6.0 POLICIES:These rules are to be used in the administration of King County Code Chapters 14.65, 14.75 and 14.80. Individuals pursuing development applications in King County may expect the Department to follow these rules and procedures in its determinations of mitigation payments and intersection standards. Nothing in the rules shall supersede or conflict with state law or County ordinances. These rules may be amended periodically as determined by the Department. Situations which are not clearly specified in K.C.C. Chapters 14.65, 14.75 and 14.80 and for which no provisions are made in these rules shall be determined on an individual basis by decision of the Director.


6.1.1 Trip Generation Rates. Trip generation rates developed by the Institute of Transportation Engineers are used for individually calculated fees unless a local trip generation rate is available that is based on local studies. If the applicant provides a traffic study, it will be evaluated by Section staff, and used as approved by the Director in individual situations to determine trip generation and distribution. Mobile Homes Prior to January 1, 1991. Non-permitted mobile homes (pre-manufactured housing units) that have been on a site and occupied for at least three years prior to January 1, 1991, have "grandfather" status. A new development permit on such a site is given a credit on its MPS fees if the mobile home is replaced. Demand Management Credits. MPS impact fee credits for transportation demand management strategies will be evaluated on an individual basis, and applied according to their effect on vehicle trip generation as determined by the Director. Pass-by and Diverted Trip Credits. Fee credits for pass-by and diverted trips will be developed and applied based on published studies and on analyses and surveys conducted by Section staff. Such trip reduction credits will be reviewed and updated periodically. Current pass-by and diverted trips are available from the Section. Existing Development Credit. Fee credit shall be given for trips associated with existing development or use on the site of the proposed development, provided that such existing development or use is demolished and has been in existence and occupied within the three consecutive years prior to the date of development permit application.

6.1.2 Payment of Fees. When a single lot development is located in more than one MPS fee zone the applicable fee shall be the fee associated with the zone of access. In the case of plats with more than one access, the Director shall determine which fee shall apply. Optional Payment at Recording. When an applicant chooses to pay MPS fees at recording, fees will be paid for all lots being recorded at the same time. Development prior to January 1, 1991. An applicant who chooses to exercise the option to pay the MPS fee at recording and whose formal plat or short plat subdivision application was made prior to January 1, 1991 will pay the MPS fee in effect on January 1, 1991. All other formal plat and short plat subdivision developments choosing to pay at recording will use the fee schedule in effect at the time of plat application.

6.1.3 Administrative Fees. Administrative fees are collected on the basis of one such fee for each permit or transaction.

6.1.4 MPS Funds. Department staff shall review and reconcile at least monthly the mitigation payments deposited into the MPS trust and agency fund (Fund No. 6960) established by Section 50 of Ordinance 11617 with the transaction information on MPS payments provided by DDES. Any errors, omissions, overpayments, or underpayments shall be identified, and appropriate corrective actions taken by Department staff. MPS Revenues. A quarterly review of expenditures for MPS projects will identify the MPS revenues available to be transferred into the revenue accounts of the applicable pooling projects in the Road Construction Fund (Fund No. 3860). Revenues shall be transferred at least twice yearly when possible. The MPS revenues so transferred shall not exceed expenditures. Documentation of each such transfer will identify which MPS payment transactions comprise the transfer. This Department procedure allows transferred revenues to be identified as expended, and MPS revenues remaining in the MPS Fund as unexpended, in order to meet the six year statutory deadline for the expenditure of MPS revenues.

6.1.5 MPS. MPS fee payments for canceled or withdrawn permits are returned to the applicant unless a replacement permit application is submitted. Permit applications for the same parcel in the future are subject to the applicable MPS impact and administrative fee schedule that is in effect when the new development permit application is submitted to DDES. Transferability of Payment. A mitigation payment may be transferred from a canceled permit to a new replacement permit for the same site with no change in MPS fee amount, provided that the new permit is submitted at the time of cancellation and provided that the use associated with the new permit has the same transportation impacts as the canceled permit. No administrative fee will be charged for replacement permits. Refund Based on DDES Denial. The MPS administrative fee is not refunded unless a permit application is denied by DDES. Refund Interest. When the dates of payment and refund are more than thirty days apart, then a refund payment shall include interest provided that the amount of interest is greater than five dollars. Calculation of Interest. Interest shall be calculated using the annual investment rate for the current year for fund investments as reported by the King County Office of Finance.

6.1.6 MPS Fee Exemptions. The following conditions will apply for school and low and moderate income housing exemptions: Exemptions for Public Schools. The exemption for public school districts applies only to public schools and not to private or Sunday schools. Schools shall be exempt from both MPS administrative and impact fees. Exemption or Reduction for Low and Moderate Income Housing. Low and moderate income housing fee reductions or exemptions are administered according to K.C.C. Section 14.75.140 by the Department of Community and Human Services or its successor agency.Approval of any exemption for low income housing reasons is not a waiver of the MPS administrative fee.The portion of the MPS administrative fee for a development permit receiving a low or moderate income exemption that is attributable to the Roads Division is transferred to the Planning and Community Development Division by the Finance Unit; such transfer of funds provides for the cost of processing the exemption. Public Funding for Exemptions. MPS impact fees for schools and housing exemptions shall be paid from other public sources and not be redistributed to new developments.


6.2.1 Significant Adverse Impacts. The determination of significant adverse impacts will be done in a traffic impact study that follows procedures and techniques approved by the Director, and that receives approval by the Director upon completion. Only the approved impact study will be used to determine transportation mitigation needs, safety improvements, schedules for completion, and the proportional costs of needed improvements that are attributable to the applicant. Needed mitigation shall take into account the committed transportation projects used to determine concurrency, the MPS project list, and the scheduling of critical safety improvements. The Director may require at least the following information as part of the traffic impact study:

Project identification and full description, Proposed trip generation and substantiating references, Traffic distribution and assignment for the morning and afternoon peak hour, Existing and calculated LOS at designated intersections, Proposed mitigation measures and resultant LOS, and Identification of existing and future safety problems and appropriate corrective measures.

The Director will require the use of cumulative development data, trip generation, trip distribution, and trip assignment methods that are acceptable to the Department.

6.2.2 Trip Generation Rates. Trip generation rates developed and published in the most recent edition of the Trip Generation Manual by the Institute of Transportation Engineers are used unless a local trip generation rate is available that is based on local studies. If the applicant provides a traffic study, it will be evaluated by the Traffic Section, and used as approved by the Director in individual situations to determine trip generation and distribution Standards and warrants. Standards and warrants shall be those approved by King County in its Comprehensive Plan, in Title 14 of the K.C.C., and in the Road Standards (K.C.C. 14.42). Turning Lanes. Turning lanes must be provided at the direct access and directly serving access intersections if they are warranted in the horizon year of the development using the standards in the WSDOT design manual. The Director may require turning lanes at the direct access and directly serving intersections for potential safety improvements, or, in conjunction with the construction of road improvements that affect (e.g. direct access in proximity to, but not within the existing limits of) an existing turn lane. Traffic Signals. Traffic signals must be provided at the direct access and directly serving access intersections if warranted by the MUTCD at the horizon year of development. Proportionate cost-sharing of traffic signals may be required to address cumulative traffic impacts to intersections identified on the County's signal priority array.

6.2.3 Intersection Improvements. Developments which will create a traffic safety or operational problem according to their traffic impact studies, or which will result in or add to a LOS "F" condition at intersections providing direct access, will be subject to the following conditions for final development approval:

* Conformance with Road Standards. The applicant will fund or provide for the improvements needed to conform to the Road Standards; Meet Level of Service "E." The applicant will fund or provide for the intersection improvements needed to achieve LOS "E" or return to its pre-project condition;
* Reducing Traffic Impacts.
The applicant may reduce the traffic impacts of the proposed development by reducing the size of the project, by altering the mix of uses in the project, or by using approved transportation demand management strategies to reduce the number of new peak hour direction trips; and
* Fair Share Contribution.
The applicant will contribute a fair share of the costs to complete the needed intersection improvements as determined by the traffic impact study and the Director.

6.2.4 Exceptions Director/Judgment Authority. Exceptions to the conditions and requirements of the IS chapter of Title 14 and to these rules may be granted by the Director when, in his judgment, extraordinary conditions exist which make full compliance infeasible. Final decisions on such exceptions will be determined as follows:

* Exceptions in Approving Ordinance. For subdivisions, UPD’s, unclassified use permits, and urban planned developments, the Director must find that there are valid reasons for an exception, and such exception must be granted in the approving ordinance. The ordinance will be determinative and conclusive as to the development’s compliance with the IS;
* Conditional Use Permits. For conditional use permits, the written decision of the Director will be determinative and conclusive regarding the development’s compliance with the IS, unless the decision is subsequently appealed to the Hearing Examiner, whose decision will then be determinative; and
* Commercial Building Permits. For commercial building permits, the written decision of the Director is determinative, unless the decision is appealed to the Hearing Examiner, whose decision will then be determinative.

6.2.5 Applicant Cost Sharing Agreements. If the mitigation measures required of an applicant are also required to mitigate the impacts of other developments proposed in a similar time frame, then the applicant may choose to enter into a proportional cost sharing agreement with other affected applicants for such improvements, provided that the County will not administer proportionate shares unless the affected applicants have executed a legal memorandum of understanding for sharing the cost of the improvements. The memorandum must specify the proportionate costs and responsibilities for the construction of the improvements. An acceptable financial security must be provided for the costs of the required improvements by one or more of the applicants.

6.2.6 Full Funding for Frontage Improvements. The County may require applicants to build or fund one hundred percent of the cost of any required frontage improvements in accordance with K.C.C. 14.42 Road Standards. This requirement will be made if the abutting roadway is not scheduled in the CIP for construction of such improvement within four years of development approval. Deposit of a proportionate cost-share (fee-in-lieu of improvement) may be required if the improvement is identified in the CIP for construction.

6.2.7 Appeals of Director’s Final Decisions. Appeals of the Director’s final decisions, together with appeals arguments, shall be made to the Director for hearing by the Hearing Examiner within ten working days of receipt of such final decision. The results of such appeals will be filed with DDES within ten days of the decision by the Hearing Examiner.

6.2.8 State Facilities and Other Local Jurisdictions. The Intersection Standards chapter of Title 14 will apply to the public roads in unincorporated King County, including State highways, except for freeways. Improvements to State and other Local Jurisdiction’s facilities will only be required under these rules if an interlocal agreement to provide specified improvements is executed by the County, the State or Local Jurisdiction, and the applicant. Such an agreement will only be initiated when the State or Local Jurisdiction requests specific improvements. Meeting Interlocal Agreement Conditions. A development will not receive final approval until it has fulfilled all IS conditions required by the County, and required by an interlocal agreement. Fulfillment may be achieved by the applicant providing a financial instrument to the Director in a form satisfactory to the County.

6.2.9 One Time Application of IS. The conditions imposed by the IS chapter of Title 14 and administered by these rules will be applied only once to a development, unless the development is changed or modified so as to require further County review and approval and which would result in greater traffic impacts than those considered in the traffic impact study.

6.2.10 County Authority. These rules do not limit the authority of the County to deny or to approve with conditions the following:

* Zone reclassification requests based on traffic impacts;
* Development or zone reclassifications if determined to be a hazard to the public health, safety, or welfare, or that would result in adverse environmental consequences from direct traffic impacts that cannot be fully mitigated by intersection improvements; and
* Developments reviewed under the authority of SEPA.

6.3 Actions Not Covered By Rules/Regulations.

6.3.1 Relation to State laws and County ordinances. Nothing in these rules shall supersede or conflict with State law or County ordinances. These rules may be amended periodically as determined by the Department. The language of these rules shall be broadly interpreted within the context of Title 14 and the adopted Comprehensive Plan.

6.3.2 Authority of Director. Situations which are not clearly specified by ordinance, and for which no provision is made in these rules, shall be determined by the decision of the Director using legal and technical advice from county sources.


7.1 Intersection Standards

Action by:Action:
Applicant 7.1.1 Submits development application and fees to DDES.
DDES 7.1.2 Refers MPS and IS evaluation to Department.
KCDOT 7.1.3 Determines fee and intersection improvements and sends report to DDES.
Applicant 7.1.4 Pays fee to DDES and completes required improvements as part of development approval. Files appeal as needed.

7.2 Mitigation Payment System Program – Residential Fees

Action by:Action:
CIP and Planning Section 7.2.1 Develops MPS residential fee schedule and corresponding zone map. Transmits fee schedule and map to DDES.
DDES 7.2.2 Incorporates the residential fee schedule and map into their PERMITS and GIS systems.
Applicant 7.2.3 Submits a residential development application to DDES.
DDES 7.2.4 Determines appropriate MPS residential fee and assesses MPS fee to development application.
Applicant 7.2.5 Appeals MPS residential fee.

CIP and Planning Section
7.2.6 Reviews residential proposal, evaluates reasons for the appeal, renders a decision on the appeal, sends decision to the applicant, DDES and Road Services Division.
Applicant 7.2.7 Appeals CIP and Planning Section's decision to the Hearing Examiner.
Hearing Examiner 7.2.8 Conducts a public hearing on the appeal, reviews public testimony on the appeal and renders a decision. Informs applicant, DDES, CIP and Planning Section of decision.
Applicant 7.2.9 Pays the residential MPS fee.
7.2.10 Collects the MPS residential fee and transmits the fee to Roads Services.
Road Services Division 7.2.11 Receives the MPS residential fee from DDES, checks amount received against amount assessed, disperses fee to appropriate Road fund accounts.

7.3 Mitigation Payment System Program – Commercial Fees

Action by:Action
CIP and Planning Section 7.3.1 Develops the MPS computer model and transportation network system. The MPS model evaluates commercial applications, forecasts the number of additional trips to be added to the network based on the commercial use and determines the dispersion of the traffic onto the roadway network.
7.3.2 Submits a commercial development proposal to DDES.
7.3.3 Transmits commercial application to CIP and Planning Section for MPS fee determination.
CIP and Planning Section 7.3.4 Reviews commercial proposal, determines MPS fee, sends MPS fee letter to applicant, transmits fee information to DDES and Road Services Division.
Applicant 7.3.5 Appeals MPS commercial fee.
CIP and Planning Section 7.3.6 Reviews original proposal, evaluates possible changes to original proposal, possible technical errors, and renders a decision. sends decision to applicant, DDES, and Roads Services.
Applicant 7.3.7 Appeals CIP and Planning Section decision to Hearing Examiner.
Hearing Examiner 7.3.8 Conducts a public hearing on the appeal, reviews public testimony and renders a decision. Informs applicant, DDES, and CIP and Planning Section of decision.
Applicant 7.3.9 Pays commercial MPS fee.
DDES 7.3.10 Collects the commercial MPS fee, transmits the fee to Road Services.
Road Services Division 7.3.11 Receives the MPS commercial fee from DDES, checks amount received equals amount assessed. Disperses MPS fee to appropriate road project accounts.


8.1 The Department is responsible for:

8.1.1 Analyzing and evaluating development applications involving transportation mitigation fees, traffic studies, and intersection operation.

8.1.2 Maintaining a current transportation model and database.

8.1.3 Calculating, assessing and collecting residential and commercial mitigation impact fees and assessing intersection improvements.

8.1.4 Coordinating mitigation fee information to the applicant, DDES and Roads Services.8.1.5 Amending these rules as needed.

8.1.6 Making SEPA recommendations regarding traffic safety, operational impacts, on-site circulation, and direct access to DDES.

8.2 The Department of Development and Environmental Services is responsible for:

8.2.1 Making available appropriate information and forms regarding the county’s permit application process and Mitigation Payment System programs.

8.2.2 Coordinating with DOT the MPS fee determination process for residential and commercial development permits. Collecting MPS fee payments. Dispersing MPS fees to the Roads Services Division.

8.2.3 Making SEPA determinations based on King County Department of Transportation recommendations regarding traffic safety, operations impacts, on-site circulation, and direct access.

8.3 The Hearing Examiner is responsible for:

8.3.1 Adjudicating appeals of the Countys decisions.

8.4 The applicant is responsible for:

8.4.1 Appealing, as needed, mitigation or intersection improvement decisions rendered by the Department of Transportation.