Chapter 8.12


8.12.010    Authority – Title – Purpose.

8.12.020    Revenue fund created.

8.12.030    Applicability.

8.12.040    Definitions.

8.12.050    Rates and service charges.

8.12.060    Billing and billing procedures.

8.12.070    Rate adjustments and appeals.

8.12.080    Use of funds.

8.12.090    Lien for delinquent charges – Enforcement.

Legislative history: Ord. 99-474.

8.12.010 Authority – Title – Purpose.

This chapter is adopted under the authority of Chapter 35.67 RCW, and shall be known as the Mill Creek surface water utility (hereinafter “utility”). The purpose of the utility and this chapter is to establish a permanent funding source to provide the revenue needed to adopt and implement a surface water management program (hereinafter “program”) in the city. (Ord. 2014-789 § 1 (Exh. A); Ord. 2009-702 § 2 (Exh. C); Ord. 2001-534 § 1)

8.12.020 Revenue fund created.

There is hereby created an enterprise fund known as the Mill Creek surface water fund (hereinafter “fund”). All fees and charges imposed by the utility and this chapter shall be placed in said fund for the purpose of paying all or any part of the costs and expenses related to (A) the adoption and administration of the program, (B) the acquisition, installation, addition, improvement, replacement, repair, modification, maintenance and operation of surface water facilities under the program, and (C) enforcement activities arising under the program. (Ord. 2014-789 § 1 (Exh. A); Ord. 2009-702 § 2 (Exh. C); Ord. 2001-534 § 1)

8.12.030 Applicability.

This chapter shall apply to all real property in the city, including public and private property, unless specifically exempted therefrom. (Ord. 2014-789 § 1 (Exh. A); Ord. 2009-702 § 2 (Exh. C); Ord. 2001-534 § 1)

8.12.040 Definitions.

The following words and phrases shall have the following meanings unless the context clearly indicates otherwise:

A. “City” shall mean the city of Mill Creek, Washington, or, as indicated by the context, may mean the city manager, or other official, officer, employee or agency representing the city in the discharge of his or her duties. Where this chapter authorizes decisions by the “city,” the city manager is authorized to make such decisions or delegate such authority to another employee/agent of the city. All requests for city decisions shall be filed with the city clerk, who shall forward the request to the appropriate city agent.

B. “City road” shall mean every public right-of-way, excluding state roads, in the city.

C. “Developed lot” shall mean the boundaries of a lot/plot of land approved by the city or county through a subdivision, lot line adjustment, or binding site plan. A developed lot may contain multiple parcels that are each subject to rate assessments (e.g., condominium parcels).

D. “Duplex” shall mean every residential structure accommodating two attached residential dwelling units.

E. “Equivalent service unit” or “ESU” shall mean the unit of measurement by which utility rates under this chapter are assessed. Each single-family residential parcel, duplex unit, and townhouse unit in the city shall be deemed to be one ESU. For all other parcels and developed lots, one ESU is equal to 3,000 square feet of measured or estimated impervious surface area.

F. “Impervious surface” shall mean hard surfaced areas that prevent or hinder the entry of water into the soil mantle and/or cause water to run off the surface in greater quantities or at an increased rate of flow than under natural conditions. Common impervious surfaces include, but are not limited to, rooftops, concrete or asphalt roads, sidewalks and paving, walkways, patios, driveways, parking lots or storage areas, and gravel, hard-packed dirt, oiled or other surfaces which impede the natural infiltration of surface water or which change runoff patterns existing prior to development or installation of the impervious surface.

G. “Parcel” shall mean the smallest separately segregated legal unit or plot of land having identified boundaries or which is documented for real property purposes, and having a tax lot number assigned by the Snohomish County assessor/treasurer.

H. “Rate charge” shall mean the amount owed after applying the appropriate unit rate to a particular parcel and/or developed lot based upon factors established by this chapter. See Table 8-1.

I. “Service charge” shall mean the amount incurred by the city in providing specific services to a given parcel and/or to the parcel’s surface water control facilities; provided, that such service charges shall not be imposed under this chapter for the development, construction, or reconstruction of property.

J. “Single-family residential parcel” shall mean every parcel in the city on which a residential structure (including mobile homes) accommodating one dwelling unit is located, and as may be defined in the city’s land use and development codes.

K. “Surface water control facilities” shall mean surface water control facilities as defined in the program.

L. “Townhouse unit” shall mean a single-family residential condominium unit falling under the provisions of Chapters 64.32 and 64.34 RCW which is attached to one or more residential condominium units and separated one from another by common side walls extending from foundation to roof with each dwelling unit having a separate, direct entrance from grade. Townhouse units shall include all residential condominium units found in a row, linked, patio, garden court, or other styles which meet the criteria of this definition.

M. “Undeveloped parcel” shall mean any unimproved parcel without impervious surface area, including but not limited to land used for open space, and as may be defined by the city’s land use and development codes. Public sidewalks, street improvements, retaining walls on an otherwise undeveloped parcel shall not affect the parcel’s undeveloped status.

N. “Unit rate” shall mean the dollar amount determined by the city council to be charged per one ESU. (Ord. 2014-789 § 1 (Exh. A); Ord. 2009-702 § 2 (Exh. C); Ord. 2001-534 § 1; Ord. 2000-501 §§ 1, 2, 3)

8.12.050 Rates and service charges.

A. Rate Factors. Rates are based on the estimated relative contribution of surface and stormwater runoff from a given parcel or developed lot to surface water control facilities. Relative contributions are based on land use classifications, parcel/developed lot size, and the amount of estimated impervious surface area covering a parcel/developed lot.

B. Unit Rate Established. The unit rate for use under Mill Creek Ordinance No. 99-474 and the Mill Creek surface water utility, all as codified in this chapter, is hereby established at the rate of $150.00 in 2019, $175.00 in 2020, and $200.00 in 2021 per equivalent service unit (ESU) commencing as of January 1, 2019, said rate to increase at three percent per year thereafter through December 31, 2026.

C. Service Charge Factors. Service charges shall be based on specific services provided by the city to a given parcel and/or to the parcel’s surface water control facilities.

D. Service Charges. Service charges shall be the total cost to the city for providing specific services to a given parcel or to surface water control facilities associated with one or more given parcels.

Without limiting the foregoing, and as example only, such services may include the cost of repairs, restoration and/or cleaning needed to bring the surface water control facility up to its intended operating efficiency. The city council may establish from time to time, by resolution, the cost of specific service charges; provided, that in the absence of a resolution, the city shall apply its actual costs of supplies, time, material, personnel costs (including benefit and other applicable costs), and other expenses to determine the cost of a given service performed under this chapter.

E. Parcels containing new or remodeled commercial buildings that utilize a permissive rainwater harvesting system as defined in the Washington State Building Code Council’s Permissive Rainwater Harvesting System Guidelines for Nonresidential Occupancies (2002 or as amended) qualify for a 10 percent discount off the unit rate. To qualify for the discount, the system must be approved by the city and designed to collect and use at least 95 percent of the average annual runoff volume from the building roof. A system that involves indoor uses of rainwater must also be permitted by Snohomish County department of health to qualify for the rate reduction. Qualifying for the monthly service rate reduction does not relieve the property owner from the obligation to comply with applicable stormwater and drainage code requirements for the buildings and site.

Table 8-1 

Class of Property

Rate Charge

Single-family residential parcel and townhouse unit

The unit rate assigned to one ESU.


Number of dwelling units on the parcel times the unit rate.

All other developed parcels and developed lots

Estimated or measured impervious surface area of the developed lot divided by the square footage of one ESU, but not less than one, times the unit rate. In the absence of measured impervious surface area or other information as may be used by the city, impervious surface area shall be estimated by multiplying the developed lot size by a density of development factor of 90 percent.

If a developed lot contains multiple parcels (e.g., condominium building), each parcel owner within the developed lot shall be responsible for paying an equal share of the rate charge attributable to the developed lot. If at the time of development or any time thereafter owners of a developed lot desire a different method of allocating the rate charge for the developed lot, they may provide the city with a recorded agreement signed by all owners of the developed lot that provides for an alternative allocation method. The city reserves discretion to accept or reject the alternative allocation method for its billing purposes. If accepted, the alternative method will apply only to future rate charges. If rejected by the city, the owners will be responsible for reallocating responsibility among themselves pursuant to their agreement.

Undeveloped parcels

No charge.

City roads

No charge.

State roads

No charge.

(Res. 2018-576 § 1; Ord. 2014-789 § 1 (Exh. A); Ord. 2003-559 § 1; Ord. 2001-534 § 1; Ord. 2000-501 § 4)

8.12.060 Billing and billing procedures.

A. Annual Rate Charges. All parcels and/or developed lots subject to rate charges under this chapter shall be assessed annually for the calendar year (January 1st through December 31st). Billing statements may be sent directly to property owners or included within annual property tax statements pursuant to applicable interlocal agreement(s) with Snohomish County. Charges included as part of annual property tax statements shall be paid through the county as part of the tax payer’s property tax payments. Charges billed separately from tax statements shall be paid in accordance with payment instructions included within the billing statement. With the exception of new development, billing statements for annual rate charges will be issued by March 1st of each year. Full payment is due by April 30th of the year for which the charge is assessed. However, if at least half of the annual rate charge is paid by April 30th, the remaining amount is not due until October 31st of the year for which the charge is assessed.

B. Services Charges. All parcels subject to service charges under this chapter shall be billed promptly upon completion of the service. Any service charges remaining unpaid 30 days after invoice may be collected or foreclosed on in accordance with the usual procedures of the city, or may be subject to the lien provisions of this chapter, or both, at the city’s discretion.

C. New Development. The first annual fee assessed under this chapter for all new development shall be paid on the following schedule. The first annual assessment applied to such new development shall be payable in full on the date of approval of the civil construction plans in accordance with MCMC 3.42.210(C) as follows:

Civil construction plans approved January 1st through March 31st:

100% of annual fee.

Civil construction plans approved April 1st through June 30th:

75% of annual fee.

Civil construction plans approved July 1st through September 30th:

50% of annual fee.

Civil construction plans approved October 1st through December 31st:

25% of annual fee.

Annual fees shall thereafter be assessed and shall be due and payable as provided in subsection A of this section. If tax parcel numbers have not been assigned to a developed lot prior to the time the city submits rate/billing information to the county, the city shall bill the property owner(s) directly. (Ord. 2014-789 § 1 (Exh. A); Ord. 2006-633 § 2; Ord. 2001-534 § 1; Ord. 2000-500 § 1)

8.12.070 Rate adjustments and appeals.

A. Any person receiving a rate charge billing statement under this chapter may file a “request for rate charge adjustment” (hereinafter “adjustment request”) with the city within 30 days of the date of the first billing/tax statement issued for the underlying rate charge. Submittal of an adjustment request shall be made on forms provided by the city and shall not extend the period of payment for the rate charge.

B. Upon timely receipt of an adjustment request, the city, acting through the directors, may grant or approve a rate adjustment only in accordance with this chapter and only upon an affirmative finding that one or more of the following conditions exist:

1. The acreage or area of the parcel charged is in error.

2. The parcel is nonresidential and the actual impervious surface area of the parcel, as established by a licensed surveyor or engineer, is more than 50 percent of the maximum square footage of an equivalent surface unit greater than or less than the estimated or measured impervious surface area used in determining the rate charge.

3. The rate charged was otherwise not calculated in accordance with the terms of this chapter.

4. The parcel exists in its natural unimproved condition and will remain in its natural unimproved condition for not less than one year with no allowable human activities or manmade improvements that adversely affect water quantity or quality or otherwise create impervious surfaces.

5. The parcel is owned or leased by a public school district or private nonprofit school facility that provides activities that directly benefit the program (“qualifying activities”). Qualifying activities may include, for example, curriculum specific to the issues and problems of surface and stormwater management, and construction and/or maintenance of on-site stormwater mitigation facilities.

C. The following information may be required by the director to determine eligibility for a rate charge credit; provided, that under no circumstances shall the amount of the credit exceed either the amount of cost savings to the utility or the unadjusted rate charge:

1. Calculation of the requested credit amount based on site-specific data; and

2. Signature of and verification by the person responsible for the accuracy of the credit application material.

D. When granted, an adjustment request shall only apply to the rate charge bill then due and payable and rate charge bills subsequently issued. If an adjustment request is granted which reduces the rate charge for the current year, the applicant shall be refunded the amount overpaid in the current year only. If the city finds that a property has been undercharged, then at the city’s discretion, either a bill shall be issued which reflects the correct rate charge, or the undercharged amount shall be added to the next year’s bill. A bill reflecting a corrected rate charge shall be due and payable within 90 days of issuance.

E. The property owner shall have the burden of proving by a preponderance of the evidence that the desired adjustment request meets the requirements of this section.

F. Decisions on adjustment requests shall be made by the director based on information submitted by the applicant in the adjustment request and by the city staff. Decisions shall be made within 30 days of the date of the adjustment request, except when additional information is requested or needed by the directors. The applicant shall be notified in writing of the directors’ decision.

G. In the event that the directors determine to replace estimated impervious surface area with measured impervious surface area in the city’s rate calculation, then, in the absence of an appeal, such actual impervious surface area shall be used for future rate charge billings.

H. Decisions of the directors on adjustment requests shall be final unless, within 15 days of the date the directors’ decision was mailed, the applicant files an appeal of the directors’ decision with the hearing examiner in accordance with Chapters 4.34 and 14.11 MCMC. (Ord. 2018-830 § 4; Ord. 2014-789 § 1 (Exh. A); Ord. 2001-534 § 1)

8.12.080 Use of funds.

Rate charges collected under this chapter shall be deposited into the fund to be used only for the purpose set forth in MCMC 8.12.020. Services charges collected under this chapter shall be used to reimburse the city for its costs and expenses. (Ord. 2014-789 § 1 (Exh. A); Ord. 2001-534 § 1)

8.12.090 Lien for delinquent charges – Enforcement.

A. Parcels/accounts that are assigned a single ESU or less shall be assessed a late penalty of $10.00 for rate charges not paid when due. All other parcels/accounts are subject to being charged interest for overdue payments at the maximum rate per annum allowed by law, or such rate as may hereafter be authorized by law, computed on a monthly basis from the date of delinquency until paid. Interest shall be calculated at the rate in effect at the time of payment of the charges regardless of when the charges were first delinquent.

B. The city shall have a lien for delinquent service and rate charges, including interest and penalties thereon, against any parcel subject to such charges. Such lien shall be effective for a period of one year or the maximum period allowed by state law without the necessity of any writing or recording of the lien with the Snohomish County auditor. Such lien shall be superior to all other liens and encumbrances except general taxes and local and special assessments. Such liens shall be effective and shall be enforced and foreclosed in the manner provided by Chapter 35.67 RCW.

As an alternative to the procedure set forth in this section, the city may, at its discretion, foreclose on and/or collect delinquent service charges in the same manner as for other unpaid city charges. (Ord. 2014-789 § 1 (Exh. A); Ord. 2006-633 § 2; Ord. 2001-534 § 1)