HomeMy WebLinkAboutO-1233 - Adds Ch. 14.15, on-site storm water drainage code (Repealed by 2245),
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CIT Y 0 F MAR Y S V ILL E
Marysville,Washington
ORDINANCE NO. /~'33
AN ORDINANCE OF THE CITY OF MARYSVILLE ENACTING
A NEW CHAPTER 14.15 OF THE MARYSVILLE MUNICIPAL CODE
ESTABLISHING AN ON-SITE STORM WATER DRAINAGE CODE.
THE CITY COUNCIL OF THE CITY OF MARYSVILLE, WASHINGTON DO
ORDAIN AS FOLLOWS:
CHAPTER 14.15 ON-SITE STORM WATER DRAINAGE CODE
14.15.010 PURPOSES
This Chapter is necessary in order to minimize water
quality degradation by preventing the siltation of the City's
creeks,streams and other water bodies;to protect property owners
adjacent to developing land from increased runoff rates which
could cause erosion of abutting property;to promote sound
development policies which respect and preserve the City's water
courses;to insure the safety of the City streets and
rights-of-ways;and to decrease surface water damage to pUblic and
private property.
14.15.020 DEFINITIONS
( 1 )"Comprehens i ve Dra inage Plan"shall mean a detailed
analysis adopted by the City which compares the capabilities and
needs for runoff accommodation due to various combinations of
development,land use,structural and non-structural management
alternatives.The plan recommends the form,location,and extent
of quantity and quality control measures which would satisfy legal
constraints,water quality standards and community standards and
identifies the institutional and funding requirements for plan
implementation.
(2)"Computations"shall mean calculations,including
coefficients and other pertinent data made to determine the
drainage plan with flow of water given in cubic feet per second
(cfs).
(3)"Department"shall mean the Publ ic Works Department
of the City of Marysville.
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{4}"Design Storm"shall refer to that rainfall event
which is selected by the Department for purposes of design.The
minimum design shall be for a lO-year return period storm,unless
design discharge of the water shed exceeds 20 cfs in which case
the minimum design shall be for a 25-year return period storm.
Intensity/Duration chart used in determining runoff shall be that
as published by the U.S.Weather Bureau for Marysville.
{5}"Development coverage"shall mean all developed
surface areas within the subject property including but not
limited to rooftops,driveways,carports,accessory buildings,and
parking areas.
{6}"Drainage area"shall mean the watershed {acreage}
contributing surface water runoff to and including the subject
property.
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handling,
property.
"Drainage plan"shall mean a plan for receiving,
and transporting surface water within the subject
{8}"Eng ineer"shall mean the City Eng ineer or Public
Works Director of Marysville.
{9}"Peak discharge"shall mean the maximum surface water
runoff rate {cfs}determined for the design storm frequency.
{10}"Procedures manual"shall mean the manual of
technical and administrative procedures and requirements adopted
by the City which delineates methods to be used,the level of
detail of analysis required and other submitted requirements for
implementation of the provisions of this Chapter.
{II}"Receiving bodies of water"shall mean creeks,
streams,rivers,lakes and other bodies of water into which
surface waters are directed,either naturally or in manmade
ditches or open systems.
(12)"Retention/detention facilities"shall mean
facilities designed either to hold runoff for a short period of
time and then releasing it to the natural watercourse or to hold
water for a considerable length of time and then consume it by
evaporation,plant transpiration,or infiltration to the ground.
{1 3 }"Subj ect property"shall mean the tract of land
which is the subject of the permit and/or approval action.
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14.15.030 SUBMISSION OF A DRAINAGE PLAN
(1)A drainage plan,as defined in Section lA.15.040,
shall be submitted with applications for any of the following
permits and/or approvals:
(a)Grading permit.
(b)Shoreline substantial development permit.
(c)Flood control zone permit.
(d)Preliminary subdivision approval.
(e)Short sUbdivision approval where the
property is located within or adjacent to the flood
plain or a river or stream,or where the property
contains natural drainage swales and/or natural
retention areas which exceed one foot in depth.
(f)Binding site plan approvals for mobile home
parks,condominiums,planned unit developments,
industrial parks and shopping centers.
(g)Building permits where the permit relates
to 5,000 or more square feet of development coverage on
the property.
(h)Rezones and conditional use permits where
it is determined by the City Engineer that the proposed
development will have a significant adverse impact upon
storm drainage.
(2)The same plan submitted during one permit/approval
process may be subsequently submitted with further required
applications.The plan shall be supplemented with additional
information at the request of the Department.
14.15.040 CONTENTS OF DRAINAGE PLAN
(1)Preliminary Drainage Review:All persons applying
for any of the permits and/or approvals referred to in Section
14.15.030 shall submit a simple site plan showing the character of
the existing site,natural drainage features occurring upon or
adjacent to the site,the amount of impervious surface
contemplated by the requested development,and the proposed
methods of complying with the mandatory drainage requirements of
Section 14.15.050.Ba.sed upon review of said submittal by the
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Compliance Officer and/or Engineer,further drainage plans may be
waived for any proposed activity or development which:
(a)Will not adversely impact the water quality
conditions of any affected receiving bodies of water~
(b)will not alter the surface discharge
location,alter the drainage pattern on adjoining
properties,alter drainage patterns,increase the peak
discharge,adversely increase runoff volume,or cause
any other adverse effects in the drainage area~and
(c)Will not alter the subsurface drainage
patterns,flow rates,or discharge points,nor result in
any significant adverse effects to property or
residents.
(2)Detailed Drainage Plans:For applications which do
not receive a waiver pursuant to subparagraph (1)above,a
detailed drainage plan shall be submitted for surface and
pertinent subsurface water flows,entering,flowing within and
leaving the subject property both during and after construction.
Said plan shall contain the following information:
(a)Project description
(1)Legal description of the property
(2)Names,addresses and telephone
numbers of owners and persons ordering work to be
performed.
(3)Copies of other permits and/or permit
applications such as Department of Fish and Game
Hydraulic Application,Corps of Engineers permits
and others.
(4)To the extent necessary to adequately
evaluate the accuracy of computations,the
description will show locations of existing or
proposed buildings,structures,utilities and site
improvements where the work is to be performed and
the location of any existing building or structure
on adjacent property which is within 15 feet of
the new work.
(5)Elevations,dimensions,location,
extent and the slopes of all work proposed to be
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done shown on a contour map.Such contour map
shall show the existing and proposed contours of
the land.
(6)The existing and proposed vegetative
cover,soils types including trees,shrubs,
grasses shall be depicted on a map of the site.
(7)Location of existing drainage
features which transport water onto,across or
from the site including natural creeks,swales,
artificial channels,drains or culverts.Also
locations of springs,or other subsurface water
outlets as well as ponds,lakes,swamps or
potholes shall also be shown on the contour maps.
(b)Background computations for sizing drainage
facilities:
(1)Depiction of the drainage area on a
topographical map,with acreage indicated.
(2)Indications of the peak discharge and
amount of surface water currently entering and
leaving the subject property.
(3)Indication of the peak discharge and
amount of runoff which will be generated with the
subject property,if development is allowed to
proceed.
(4)Determination of the peak discharge
and amount of water that will be generated by the
design storm frequencies as specified by the
Department at various points on the subject
property.
14.15.050
IMPROVEMENTS
MANDATORY REQUIREMENTS FOR ALL DRAINAGE
(1)Commencement of construction,grading or site
alteration work under any of the permits or approvals listed in
Section 14.15.030 shall not begin until such time as final
approval of the drainage plan has been granted by the Engineer.
(2)Surface water entering the subject property shall be
received at the naturally occurring location and surface water
exiting the sUbject property shall be discharged at the natural
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location with adequate energy dissipators to minimize downstream
damage and with no diversion at any of these points;
(3)The peak discharge from the sUbject property may not
be increased due to the proposed development;and shall not exceed
.2 cubic feet per second per acre under design storm conditions,
except for a property discharging directly to a major receiving
water,or to a public storm drain which the Engineer finds has
sufficient capacity to carry existing and anticipated loads from
the point of connection to a receiving body of water.
(4)Retention/detention facilities must be provided in
order to handle all surface water in excess of the allowed peak
discharge;
(5)Where open ditch construction is used to handle
drainage within the subject property,a minimum of 15 feet will be
provided between any structures and the top of the bank of the
defined channel.
(a)In open channel work the water surface
elevation will be indicated on the plan and profile
drawings.The configuration of the finished grades
constituting the banks of the open channel will also be
shown on the drawings.
(b)Proposed cross-section of the channel will
be shown with stable side slopes.Side slopes will be
3:1 maximum unless paved or stabilized in some manner
approved by the Department.
(c)The water surface elevation of the design
flow will be indicated on the cross-section.
(6)Where a closed system is used to handle drainage
within the subject property,all structures will be a minimum of
10 feet from the closed system.
(7)The proposed measures for controlling runoff during
construction including a statement indicating the proposed staging
of all clearing,grading and building activities.
(8)Drainage facilities shall be designed and constructed
in accordance with City standards and as directed by the
Engineer.
(9)Vegetation shall be established on areas disturbed or
other locations on the site to protect water courses from erosion,
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siltation or temperature increases.
(10)Surface water exiting from the subject property
shall have pollution control and oil separator devices installed
at the discharge point from the subject property when draining
parking lots of paved roadway surfaces or handling contaminated
storm runoff.
(11)Variances from any or all of the foregoing
requirements may be granted by the City Engineer for a good cause,
upon consideration of the following:
(a)Capacity of downstream facilities~
(b)Acceptability of receiving bodies of water;
(c)Possibility of adverse effects of retention;
(d)Utility of regional retention facilities;and
(e)Capability of maintaining the system.
14.15.060 DEVELOPMENT IN CRITICAL FLOOD,DRAINAGE AND/OR
EROSION AREAS
Development which would increase the volume of discharge
from the subject property shall not be permitted in areas where
existing flooding,drainage,and/or erosion conditions present an
imminent likelihood of harm to the welfare and safety of the
surrounding community,until such time as the community hazard is
alleviated.Where application of the provisions of this section
will deny all reasonable use of the property,the City Engineer
may waive the restrictions on development contained in this
section,provided that the resulting development shall be sUbject
to all of the remaining terms and conditions of this chapter.
14.15.070 ESTABLISHMENT OF REGIONAL FACILITIES
In the event that pUblic benefits would accrue due to
modification of the drainage plan for the subject property to
better implement the recommendations of the Comprehensive Drainage
Plan,the Engineer may recommend that the City should assume
responsibility for the further design,construction,operation,
and maintenance of the drainage facilities,or any increment
thereof,on the subject property.Such decision shall be made
concurrently with review and approval of the plan.
In the event that the City decides to assume
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responsibility for all or any portion of the design,construction,
operation,and maintenance of the facilities,the applicant shall
be required to contribute a prorated share to the estimated cost
of the facilities~provided,that such share shall not exceed the
estimated costs of improvements the applicant would otherwise have
been required to install.The applicant may be required to supply
additional information at the request of the Engineer to aid in
such determination by the City.
14.15.080 TEMPORARY EROSION CONTROLS
Control of erosion from general clearing,grading and
other construction activities shall be implemented to prevent
damage by sedimentation to streams,flood plains,watercourses,
natural areas and property of others during the construction phase
and prior to completion of the permanent erosion control
facilities.
On-site drainage controls shall minimize erosion and
return waters to the natural drainage course free of sedimentation
or other pollution to the maximum extent feasible.
Erosion control measures or devices shall be employed by
the applicant as necessary prior to the initiation of
construction.The Engineer may require additional control
measures where existing methods are failing to adequately control
erosion.
The Washington State Administrative Code,Chapter 173-201
"Water Quality Standards of Water of the State of Washington"(as
amended)is incorporated herein by this reference.The water
quality criteria and waste discharge limitations shall be enforced
by the Engineer in cooperation with the Department of Ecology,and
violators will be sUbject to the City enforcement action in
addition to any state enforcement action.The Engineer may use
Jackson Turbity units as measured with a Jackson Candle
turbidimeter instead of nephelometric turbidimeter units
monitoring of turbidity levels.
14.15.090 FEES
No fee shall be required for a preliminary drainage
review.Where a detailed drainage plan is required there shall be
a plan check fee paid in advance in the amount of $150.00,and an
inspection fee to reimburse the City for staff time spent on the
site at the rate of $15.00 per hour with a minimum fee of $30.00
per job.
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14.15.100 REVIEW AND APPROVAL OF PLANS
All storm drainage plans prepared in connection with any
of the permits and/or approval listed in Section 14.15.030 shall
be submitted for review and approval by the Engineer.
14.15.110 INSPECTIONS
The holder of any permit or approval issued subject to a
detailed drainage plan shall arrange with the Engineer for
scheduling the following inspections:
(1)Initial Inspection:Whenever work on the site
preparation,grading,excavations,or fill is ready to be
commenced,but in all cases prior thereto.
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completed.
Rough Grading:When all rough grading has been
(3)Bury Inspection:Prior to burial of any underground
drainage structure.
(4)Finish Grading:When all work including installation
of all drainage structures and other protective devices has been
completed.
(5)Planting:When erosion control planting shows active
growth.
In some circumstances not all of the above inspections may
be necessary.It shall be the discretion of the Engineer to waive
or combine any of the above inspections as dictated by
conditions.
The Engineer shall inspect the work and shall either
approve the same or notify the applicant in writing in what
respects there has been failure to comply with the requirements of
the approved plan.Any portion of the work which does not comply
shall be promptly corrected by the applicant.The Engineer may
make unscheduled site inspections to ensure compliance.
Uncorrected violations will be subject to the provisions of
Section 14.15.170.
14.15.120 BONDS AND LIABILITY INSURANCE REQUIRED
The Department is authorized to require all persons
constructing retention/detention or other drainage
treatment/abatement facilities to post surety or cash bonds.
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Where such persons have previously posted,or are required to
post,other such bonds on the facility itself or on other
construction related to the facility,such person may,with the
permission of the Engineer and to the extent allowable by law,
combine all such bonds into a single bond,provided that at no
time shall the amount thus bonded be less than the total amount
which would have been required in the form of separate bonds,and
provided further that such a bond shall on its face clearly
delineate those separate bonds which it is intended to replace.
(1)CONSTRUCTION BOND.Prior to commencing construction,
the person constructing the facility shall post a construction
bond in an amount sufficient to cover the cost of conforming said
construction with the approved drainage plans.Alternatively,an
equivalent cash deposit to an escrow account administered by a
local account bank may be allowed,at the City's option.
(2)MAINTENANCE BOND.After satisfactory completion of
the facilities and release of the construction bond by the City,
the person constructing the facility shall commence a one-year
period of satisfactory maintenance of the facility.A cash bond
to be used at the discretion of the Engineer to correct
deficiencies in said maintenance affecting public health,safety
and welfare must be posted and maintained throughout the one-year
maintenance period.The amount of the cash bond shall be
determined by the Engineer.In addition,a surety bond or cash
bond to cover the cost of design defects or failures in
workmanship shall also be posted and maintained through the
one-year maintenance period.Alternatively,an equivalent cash
deposit to an escrow account administered by a local account bank
may be allowed,at the city's option.
(3)LIABILITY POLICY.The person constructing the
facility shall maintain a liability policy in an amount to be
determined by the City which shall name the City of Marysville as
an additional insured and which shall protect the City from any
liability for any accident,negligence,failure of the facility,
or any other liability whatsoever,relating to the construction or
maintenance of the facility.Said liability pOlicy shall be
maintained for the duration of the facility by the owner of the
facility,provided that in the case of facilities assumed by the
City for maintenance pursuant to section 14.15.130,said liability
policy shall be terminated when said City maintenance
responsibility commences.
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14.15.130 CITY ASSUMPTION OF MAINTENANCE
The City may assume the maintenance of retention/detention
facilities after the expiration of the one-year maintenance period
if:
(1)All of the requirements of this chapter have been
fully complied with:
(2)The facilities have been inspected and approved by
the Department after the first year of operation:
(3)The surety bond required in Section 14.15.120 has
been extended for one year,covering the City's first year of
maintenance:
(4)All necessary easements entitling the City to
properly maintain the facility have been conveyed to the City.
14.15.140 RETROACTIVITY RELATING TO CITY MAINTENANCE OF
DRAINAGE FACILITIES
If any person constructing retention/detention facilities
and/or receiving approval of drainage plans prior to the effective
date of this chapter demonstrates,to the City's satisfaction,
total compliance with the requirements of this chapter,the City
may,aft@r insp@ction,approval,and acknowledgement of the proper
posting of the requir@d bonds as specified in Section 14.15.120,
assume maintenance of the facilities.
14.15.150 MAINTENANCE OF DRAINAGE FACILITIES BY OWNER
In the event that the City elects not to assume the
operation and maintenance responsibility for the facilities,it
shall be the responsibility of the owner of the property,his
heirs,successors and assigns,to operate,maintain,repair and
replace said facilities in continuous compliance with the
standards and specifications of the Department.The Engineer
shall have authority to periodically enter upon the property and
inspect the facilities to insure such compliance.
14.15.160 APPLICABILITY TO GOVERNMENTAL ENTITIES
All municipal corporations and governmental entities shall
be required to submit a drainage plan and comply with the terms of
this ordinance when developing and/or improving,land within the
incorporated areas of the City of Marysville or within adjacent
areas which may affect the City.
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14.15.170 ENFORCEMENT
(1)Nuisance:
any provision of this
declared to be unlawful
such.
Any structure or condition which violates
chapter shall be and the same hereby is
and a public nuisance and may be abated as
(2)Cumulative Civil Penalty:In addition to or as an
alternative to any other penalty provided herein or by law,any
person who violates the provisions of this title,the Procedures
Manual,or an approved Detailed Drainage Plan,shall incur a
cumulative civil penalty in the amount of $100.00 per day from the
date set for correction,pursuant to subsection (3),until the
violation is corrected.
(3)N~t2:~~_~!_Vi~..!.~ti~£_.:._A~~~~~~~£t_~f_P~£~..!.tx.:
Whenever the Engineer has found or determined that a violation is
occurring the compliance officer is authorized to issue a notice
of violation directed to the property owner or occupant:
(a)The notice of violation shall contain:
(1)The name and address of the violator,
if known.
(2)The street address,when available,
or a legal description sufficient for
identification of the building,structure,
premises,or land upon or within which the
violation is occurring.
(3)A statement of the nature of such
violation(s).
(4)A statement of the action required to
be taken as determined by the Engineer and a date
for correction,which shall be not less than three
(3)weeks from the date of service of the notice
of violation,unless the Engineer has determined
the violation to be hazardous and to require
immediate corrective action or unless the
corrective action constitutes a temporary erosion
control measure.
(5)A statement that a cumulative civil
penalty in the amount of $100.00 per day shall be
assessed against the person to whom the notice of
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violation is directed for each and every day
following the date set for correction on which the
violation continues;and
(6)A statement that the Engineer's
determination of violation may be appealed to the
City Council by filing written notice of appeal,
in duplicate,with the City Clerk within twenty
(20)days of service of the notice of violation.
The per diem civil penalty shall not accrue during
the pendency of such adminstrative appeal unless
the violation was determined by the Engineer to be
hazardous and to require immediate corrective
action or was determined by the Engineer to
constitute a temporary erosion control measure.
(b)The notice of violation shall be served
upon the person(s)to whom it is directed either
personally,or by mailing a copy of the notice of
violation by certified mail,postage prepaid,return
receipt requested,to such person at his last known
address.Proof of personal service shall be made at the
time of service by a written declaration under penalty
of perjury executed by the person affecting service,
declaring time,date and the manner by which service was
made.
(4)Collection of Civil Penalty:The civil penalty
constitutes a personal obligation of the person(s)to whom the
notice of violation is directed.The City Attorney,on behalf of
the City,is authorized to collect the civil penalty by use of
appropriate legal remedies,the seeking or granting of which shall
neither stay nor terminate the accrual of additional per diem
penalties so long as the violation continues.
(5)Compromise Settlement and Disposition of Suits:The
Engineer and the City Attorney are hereby authorized to enter into
negotiations with the parties or their legal representatives named
in a lawsuit for the collection of civil penalties,to negotiate a
settlement,compromise or otherwise dispose of a lawsuit when to
do so will be in the best interests of the City,provided that a
report shall be submitted to the City Council in any instance when
a compromise settlement is negotiated.
PASSED by theMdayofAI'91L
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ATTEST:
~IJ'C ITY CLE....n-{..br~.~=---=so~:::;p=:::...=::=;..10'---
APPROVED AS TO FORM:
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SOUTHEAST MARYSVILLE
REGIONAL SURFACE HATER MANAGEMENT PROGRA~1
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1500/330
SOUTHEAST MARYSVILLE
REGIONAL SURFACE ~lATER MANAGEMENT PROGRA~1
Ju'ly 7,1981
Prepared for the
CITY OF MARYS~ILLE
Prepared by
Hammond,Collier &Wade -Livingstone Associates,Inc.
4010 Stone Way North
Seattle,Washington 98103
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HAMMOND,COLLIER &WADE -LIVINGSTONE ASSOCIATES,INC.
CONSULTING ENGINEERS
GEORGE R.HAMMOND.P.E.
WILUAM P.COl..UER,P.E.
L.ARRV R.WADE.P.E.
O.LIVINGSTONE.P.E..RETIRED
BRUCE L.IVINGSTONE.P.E.
TEO ~.LU£BKE.P.E.
DAVID A.SWENSON.P.E.e DOUGLAS .J •.JACOBSON.P.E.
ROBERT E.BERGSTROM,P.E:.
RANQALL O.HERRALA,P.E.
FREDERICI<G.KERN,P.E.
4010 STONE WAY NORTH
SEATTLE.WASHINGTON 98103
TELEPHONE:(2061 632-2664
1-800-562'7707 (WASH.ONLY)
610 N.MISSION STREET.SUITE C4
WENATCHEE.WASHINGTON 98801
TELEPHONE:(509)662-1762
July 7,1981
GORDON S.RECTOR.P.L.S.
CALE O.ERDAHL.P.L.S.
KEN·NETH L.EDINGTON,P.L.5.
98270
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City of Marysville
Ci ty Ha 11,Ci ty Pa-rk
Marysvi l Ie,Washington
Attn:~1r.Richard W.Deming,City Administrator
Mr.Bill ButTer,P.E.,Director of Public Works
Re:Southeast Marysville Regi'onal Surface Water Management Program
Gentlemen:
Transmitted with this letter is our Regional Surface Water Management
Program for Southeast t1arysvi 11 e. In the report,we have descri bed
elements of the exi'sti ng and future storm water runoff conditi ons for
the region and have identified several sites for surface water retention.
The report analizes the impact of increased development and the corresponding
increase of surface water runoff in the Munson Creek and Allen Fork Watersheds.
The proposed Surface Water f·1anagement Program i dentifi es 1ocati ens where
additional surface water retention is recommended to adequately manage a 25
year frequency storm.
Thank you for the opportunity to be of service.If you have any questions
or comments concerning your utilization of this document,please contact
our office.
Sincerely yours,
HAMMOND,COLLIER &WADE -LIVINGSTONE
ASSOCIATES,INC.
Larry R.Wade,P.E.
LRW:kjh
Encl.
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Section One:
Secti on Two:
Section Three:
Section Four:
TABLE OF CONTENTS
Letter of Transmittal
Foreword
Summary and Recommendations
SURFACE WATER MANAGEMENT TECHNIQUES
National Trends
Local,Pol i cies
Regional Retention Programs
Maintenance Costs
WATERSHED PLANNING CONSIDERATIONS
Southeast ~1ar.ys-vi 11 e Watershed
Environmental Characteristics
Fisheries
RECOMMENDED COMPREHENSIVE PLAN
The Wa"tershed Basins
Basin Control Programs
Lost Creek, Quilceda and Lower Allen Creek Basins
Munson Creek,Allen Fork and Middle Allen Basins
All en Creek Bas in
SURFACE WATER HYDRAULIC ANALYSIS
Study ~1ethods
ComDuter Model -SWMM
Surface Water Modeling
Catchment Areas
Storm Durations
Rainfall Data
Calibration and Programming
Satur~ted Soil Conditions
Future Land Develooment
Regi ana1 Retenti on'Sites
Summary of Stream Flows
Evaluat f ons and Recommendations
Bibliography
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LIST OF FIGURES
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(1) S.E.MarysNille Regional Surface Water Management Program
(2) Existing- Fisheri-es Habitat
(3)Wa ters hed Bounda-ries
(4)Potential Runoff Control Program
(5)Computer Model
(6)Basi-n Retentiorr and Management Program
LIST OF TABLES
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•(1)Recommended Surface Water Management Program 7
(2)Allen Creek Storm Water F10\vs 11
•(3)Munson Creek Storm Water Flows 12
(4)Computer Model for Future Condition 14
(5)Estimated Construction Cost 17
(6)Estimated Construction Cost 18
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FOREWORD
In the past years,the public and private sectors have not attached
a high priorHy for providing and maintaining local stormwater control
systems.Public investment for surface drainage improvements iIT developing
a-reas of these United States is,however,massive.An annual capi-tal invest-
ment of nearly 4 billion dollars in 1978 represents a significant portion
of urbantzation development costs.Nevertheless,annual damages estimated at
3 bill ion dollars in 1978 resulted from surface water runoff problems (r).
Often,these damage claims must be faced squarely by the local officials.
SCOPE OF WORK
The scope of this report is to prepare a regional storm water manaqement
approach for the ~lunson Creek and Allen Creek basins and identify regional
storm retenti on ponds.A comprehensi ve system of retenti on basi ns an-d
identification of principal drainways was developed.This is consistant
with the goal to regulate up to 25 year frequency storm event flows to
approximately predeveloped rates along sensitive creek segments.
Specific creek conduit capacity and improvement needs are not addressed
in this report.
RE€OMMENDATIONS
The purpose of this report is to assist the officials and citizens of
the City of Marysville to develop a responsible stormwater management program
by documenting the existing conditions and planning for future drainage improve-
ments in order to protect against the deterorization of these water resources.
~Je recommend that the City of r~arysville circumvent the problems which
have befallen the others by pursuing a regional management approach based upon
a comprehensive drainage plan.This report,detailing the-results of our
(1)Poertner,H.G.
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regional study for the Southeast Sector of the Marysville planning area can serve
as a first step toward this goal.
The report sets forth recommendations to provide for 25 year frequency,
three hour duration storms.The recommendations are based on the premise that
planned land utilization will remain consistant w'ith the exis t tnq land use plan.
Three methods of storm water management are uti 1i.zed.The most cost effective
alternative for each area is shown in Figure 4.The fe l lowt nq surface water
management programs are recommended for each of the seven watersheds analyzed.
Lower Allen Creek Basin.Participation with regional storm retention facilities.
No retention facilities are recommended within this basin.
Middle Allen Creek Basin.Participation with reqrone l storm retention
facilities.Ground water recharge is recommended withf n this bas in.
Upoer Allen Creek Basin.On-site retention facilities are recommended.Future
soil permeability analysis may allow the utilization of ground water recharge.
Allen Fork Basin.Participation with regional storm retention facilities.
Six storm water retention facilities with a total storage volume of 23 acre feet
are recommended within this basin.The estimated total project ccst for the
six facilities is $313,000.00, in 1981 dollars.
Munson Creek Basin.Participation with regional storm retention facilities.
Five storm water retention facilities with a total storage volume of 30 acre feet
are recommended within this basin.The estimated total project costs for the
basin is $605,000.00.
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Lost Creek Basin and Quilceda Creek Subbasin.
are recommended for these two basins.
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On-site retention facilities
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Section One
SURFACE WATER MANAGEMENT TECHNIQUES
National Trends
Ouri ng the 1as t decade,the des ign'.of surface drai nage 'improvements
has been in a state of flux.For diverse reasons such a-s flood and pollution
control,groundwater recharge,f i s'hery and wild'life habitat enhancement,and
limiting the_general obligation or general revenue methods of drainage
funding,local public agencies are entertaining new ideas and enacting
new ordinances.Examples of these ordina~ces are:placing new requirements
or liabilities on the develorers,limiting the amount of allowed surface
water di scharge from a property or deve 1opt n9 new methods of fi nance.some-
time'S in the form of a user or util i ty fees.
Local Policies
Here in the Northwest,we have witnessed the coming of two new and
distinct generations of"surface water management.I.nitially,many local
counti-es and cities,led by King County and the Ci ty of Bellevue,have
instituted an ordinance requiring on-site detention of the excess surface
water runoff caused by a development.Although stt 11 in vogue,thi s concept
is now being re-evaluated because of its characteristic problems.
Regional Retention Proorams.A second concept involving regional (as opposed
to individual)management programs are now being forwarded by several public
agencies.This new approach sheds the fallacy that a simple,ordinance type
requirement applied in bla.nket fashion will prevent any new problems.Instead,
it recogni zes the fact that watersheds are dynamic in nat:ure and shoul d be
analyzed and treated as a whole entity and not viewed as just so many non-
connected pieces or subdivisions.In so doing,it dtfferent i ates between the
state of development (t .e.:land usage,formal 'drainage:system}ofea'ch watershed
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and applies different requirements to different basins in accordance with a
master or comorehensive plan.
Maintenance Cost
A second compelling reason to replace the first generation concept is
the tremendous 1i abil ity of maintenance programs costs that bef'a 11s the 1oca1
government with the acceptance of these on-site retenti-on faci Hti es.A
recent survey made by King County indicates that 95%of its on-site facilities
are not bui It according to approved plans,have not been properly designed
and/or have not been adequately maintained(_2).The County's on-site retention
program is highly controversial;an expensive and questionably effective
system which may be abandoned altogether because of staggering maintenance
costs and whose liability has been passed to the County.
(2)Journal American
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Section Two
~JATERSHED PLANNING CONSIDERATIONS
Southeast Marysvi 11 e l~atershed
A.recent evolution in local po'l i ctes .and events including growth
management planning,annexations to muni c.lpal boundaries,utility extensions
and the anticipated arrival of a new labor intensive industry have targeted
the southeast portion of the Marysville planning area for suburbanization.
To date,many residential developments have been proposed within both the
municipal and county lands which incorporate this area.The vicinity map
of Figure 1 depicts the boundary of the Southeast planning area.
Environmental Characteristics.Unlike the other sector-s of f4arysville,
the southeast area includes a large upland area of hilly ground. This region
has a glacial till soil structure and a highly developed network of streams
and drainage ways.These factors together \...ith surface water problems which
include pollution,flooding,soil ero~ion and sedimentation will certainly
accompany suburbanization affecting the quality of life for the people of this
area unless they are properly mitigated.
Fisheries.A substantial and sometimes devas tat inq impact from surface water
problems is felt upon fisheries and other water related resources.This is
particularily true here in the Pacific Northwest with our anadromous fisheries.
Figure 2 shows the existing fisheries habitat for th~southeast Marysville area.
These local streams are estimated to produce an annual fish harvest of $25,000
in thei r present state.In the futur-e, the value of thi s resource cauld range from
zero to $70,000 per year(3).The development of surface water retention facilities
can have a significant inipact upon the ftsh migration patterns.Final design of
any such facility may incorporate fish ladders,etc.,to maintain the
(3) Hendrick,D.
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,S.E.'MARYSYU.LE .
REGIONAL SURFACE'WA\"f;'e'Rt
MANAGEMENT PR06RA•..-."-'."
HAMMOND,COLLIER.&WADE
LIVINGSTONE ASSOCIATES,INC.
CONSULTING ENGINEERS
!=;EAT1LE.WASH.9BI03
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HAMMOND,COLLIER &WADE-
LIVINGSTONE ASSOC.,INC.
£onsul~1ng Engineers
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S.E. M'ARYSVILL-E
EXISTING
F,IS~E'RIES _~A8ITAT
:FIGURE 'NO:2'-"
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existing fish spawning routes.Review on an individual basis by the
Washington Fisheries Department will be required prior to the development
of a regional retention facility.
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Section Three
RECOMMENDED COMPREHENSIVE PLAN
The Watershed Basins
The seven major drainage basins and a small unnamed ei"ghth basin
\'/hich characterize the planning area are shown in Figure, 3. At the request
of Ci-tyofficials we have extended the original boundaries of this study,
roughly the existing City Limits,to include this larger planning area which
tota 1s nearly ei ght square miles , Approximately 67%of the area is currently
outside the municipal corporate limits,but could feasibly be annexed into
the City since most of it is within the present ut il i ty service boundary.
Of these drainage districts,the ~1unsi)n Creek,AlTen Fork,Middle and
Lower Allen Creek watersheds lie entirely or nearly entirely within this
planning area.In general,those major drainage districts which lie closest
to the downtown area of Marysville have greater levels of developed land use
and drainage ways.In this respect,they are less likely to need and realize
benefits from regional facilities.Conversely,the Munson Creek and Allen
Fork watersheds which are expected to undergo intensive development in the
near future are ideal candidates for such facilities.
The following sections of this report address the'technical analysis
of storm water runoff and regional retention facilities.Both the Munson Creek
and Allen Fork watersheds were extensively investigated with soecific recommen-
dations being made for stormwater channels,flow rates and facility development.
Basin Control Programs
Tooography,land use,soil type,water table and runoff pattern information
has been synthesized into Figure 4 which depicts the kind of runoff control
programs which are best suited to the land forms throughout the Southeast
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Marysville planning area.This map differentiates between generalized areas
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s.E.MARYSVILLE
WATERStED'BOUNDARIES ':;f';
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Consult1-ng:Eng1.neers '
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-TOPOGRAPHIC AREA
LIKELY TO UTILIZE
REGIONAL RETENTION =
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TOPOGRAPHIC AREA
LIKELY TO UTILIZE
GROUNDWATER
RECHARGE FACILITIES
TOPOGRAPHIC AREA
LIKELY TO UTILIZE
ON-aITE RETENTION
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:.tIVINGSTONE ASSOC..INC.
Consulting Engineers
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S.E.MARYSVILLE
POTENTIAL
RUNOFF CONTROL -PROGRAM
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which could effectively use on-site or regional retention facilities as
well as those which could potentially utilize recharge systems thereby
replenishing the ground water table and helping to maintain base flows in
the stream beds.Thes€types of considerations are embodied in the Recommended
Surface Water Management Program,shown in Table 1,which specifies different
types of pollution and runoff control requirements on a basin by basin approach.
Lost Creek, Quilceda Creek and lower Allen Creek Basins.Since large portions
of these drainage basins are either extensively developed or lie in the f locd
plains of meandering.streambed channels kharacterized by high capacity,
low velocity and tidally influenced streamflows)we are recommending that.
retention requirements be waived and that the developers particioate in
upstream projects which are likely to be more cost effective.
Munso~Creek, Allen Fork and Middle Allen Creek Basins.For the Munson Creek,
Allen Fork and Middle Allen Creek basins,we are recommending that a regional
retention Dlan be adopted and implemented.Developers in the Allen Fork water
shed and the ~unson Creek and Middle Allen Creek basins will be required to
participate in the regional detention basin,principal drainway and con~uit
improvements to be managed by the City of Marysville.
Allen Creek Basin. A technical analysis of the Allen Creek Basin is not included
in this study.At present,a portion of this basin has already been developed under
Snohomish County Single Family Residential Standards with an informal storm.
drainage system.We recommend that future developments within the watershed parti-
cipate with a yet-to-be defined regional retention program in accordance with the
subbasin planning contained in this report.It is felt that some of these regional
facilities will be able to utilize a groundwater recharge type of system though
future technical studies will be necessary to confirm and develop such concepts .
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TABLE 1
RECOMMENDED SOUTH EAST MARYSVILLE
SURFACE WATER MANAGEMENT PROGRAM
WATERSHED Lower Middle Upper Allen Munson Lost Quilceda
Allen Allen Allen Fork Creek Creek Creek
Creek Creek Creek Bas in Basin Subbasin Subbas in
Basin Basin Basin
POLLUTION CONTROL
Siltation Control
During Construc-
tion R R R R R R R
Oil Traps R R R R R R R
Sediment
Traps R R R R R R R
RUNOFF CONTROL
On-Site Reten-***tion Facilities W W R W W R R
Participation
with Regional ***Facilities R R W R R W W
Regional
Retention
Faci1ities
Constructed ***within Basin No Yes No Yes Yes No No
Regional
Groundwater
Recharge
Facilities
Constructed **** **within Basin No Yes Maybe.No Yes Maybe Maybe
*Interium status until adoption of watershed management plan for adjacent planning area
**Depends upon soil structure analysis
R:Required
W:Waived
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Secti on Four
SURFACE WATER HYDRAULIC ANALYSIS
Studv Methods
M
For larger watersheds such as Allen Fork and Munson Creek with 1281 and
936 acre watersheds respectively,estimating runoff for existing and urbanized
conditions is a complex task.In order to more accurately depict the dynamic
nature of these watersheds we have chosen to utilize a computer based hydrologic
mod~T as our analytical tool.This type of approach not only helps to document
the existing streamflow conditions but also enhances managements ability to track
the progress of urbanization and to implement a phased caoital improvement
program.By periodically updating the model with as-built information,the
~omputer program can be rerun and the interim status of the regional facilities
can be verified with adjustments being made on each fncility's operational
mode as necessary.
Comouter Model -SWMM.We have selected EPA's Stormwater Management Model
(SWMM)as the specific hydrologic model for this study.Although we recoginize
its shortcomings and liabilities,particularily its limited ability to model
a continuous simulation of actual climatic records and to accurately account
for evapo-transpi rati on and qroundwater Zs treambed i nterfl ows ,nevertheless,we
find that it's national acceotance as a primary model for estimating runoffs and
it's adaptibility to depict actual hydraulic conditions,makes it a good choice
for usage in this study.
Surface Water Modeling Considerations.All models embody the physical
characteristics of the catchment area and drainage system. ,The basic
characteristics are size,slope imperviousness and land u~e.The SWMM
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program utilizes a branched tree type of model,similar to the actual branched
network of the watershed itself.Each contributing branch of the system weighs
and evaluates the physical characteristics of the land and it's drainageways.
The SWMM program requires detailed and specific inDut information such as the
soils infiltration rate,rainfall interception and storage parameters which
must be effectively used to calibrate the model to the paritcular characteristics
of the land.The actual hydraulic routing of the rainfall is performed by
the computer1s extensive accounting system which calculates,monitors and
superimposes the rainfall and surface water runoff fr-om each of the subbasins into
the suoportive drainage system and through the watersheds stream channels.
Catchment areas.For this study,the catchment area of both the Munson Creek
and Allen Fork uater sheds were carefully subdivided using a 1 "=200'aerial
topoqraphic map.Each of these subbasins is shown in Figure 5 and is numbered
according to a branched network.Interconnecting these subbasins are a series
of open channel segments which are also numbered and modeled according to the
branched tree analogy.These segments,representing the well developed stream
channels of the watershed,are also identified in Figure 5.
Storm Durations.Perhaps the single most discretionary modeling parameter is
the selection of the rainfall event.This parameter alone differentiates between
similar basins which could be located anywhere else in the world. In the Pacific
Northwest our storms are quite unique.Even local patterns of rainfall vary
significantly.In general,the smaller the watershed,the shorter the time
duration rainfall event will be which creates a peak runoff from the basin.
Also,factor's such as slope,land use and imperviousness must be considered
when identifying which important rainfall event should be utilized in engineering
analysis or design work.
For this study.we utilized the computer itself to determine which storm
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iHCW/L PROJECT NO.1500/330
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FIGlJRE 5
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event would likely produce the peak runoff conditions.In effect,we submitted
storms of short duration,like a 30 minute summer thunderstorm as well as longer
six hour events and allowed the computer to calculate and superimpose the
stream flow rates.From this comparison,we identified separate storm intervals
for analysis of events with different probabili-ties of occurance.These critical
time duration events are noted in Tables 2 and 3.
Rainf~ll Data.The actual numerical values which must serve to characterize
the s tormvs intensity are similarly di f f i cul t.to select and of paramount
importance.Because the City of Marysville does not operate a rain gage,we
~ynthesized representative intensity /duration / frequency curves for the
Seattle area.We examined but rejected the published Washington
State Department of Transportation values,finding them not extensive enough
for our specific study area and modeling requirements.These published values
have themselves been synthesized from general precipitatton data,and are widely
used to represent an extended area of our State,not exclusively the ~1arysville
area.Since the orecipitation record for nearby Everett compares favorably with
Seattle,and because Seattle has at great expense compiled and reduced over 300
ga·uge-years of time recorded precipitation data.accurate to 0.01 inch-one minute
interval,we have selected this record as the basis of our detailed computer
input requirements for the Marysville SvJ~1M model.
vIe recommend that the Ci ty of ~1arysvi 11 e acquire a recordi ng
precipitation gauge from which invaluable records can be compiled and used to
assist future engineering projects and investigations as well as update versions
of this model.
Calibration and Programming of Computer Model
To generate the numbers necessary to make comparisons between pre-
developed and post-developed flow conditions,and to determine the design values
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TABLE 2
ALLEN CREEK STORM WATER FLOWS
•Instantaneous Peak Storm Discharge:CFS
I
STORM ALLEN FORK NODE LOCATIONS
ration_]Frequency AF -1 AF -2 AF -3 AF -4 AF -5
1ST!NG COND IT ION:--------
hour 1 year 53 6 47 7 6
hours 5 years.59 8 46 8 14
hours 25 years 117 17 85 18 28
hours 100 years 192 29 135 33 45
TURE CONDITION:
hour 1 year 143 23 119 35 42
hours 5 years 127 19 lOl 30 35
hours 25 years 184 28 137 39 49 -
hours 100 years 263 41 201 57 72
TURE CONDITION
TH REGIONAL RETENTION:
hours 25 years 92 21 60 5 23
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TABLE 3
MUNSON CREEK STORM WATER FLOWS
Instantenous Peak Storm Discharge -CFS
MUNSON CREEK NODE LOCATIONS
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Durahon ~equency M- 1 M- 2 M- 3 M- 4
EXISTING CONDITION:
1 hour 1 year 34 9 ·13 7
3 hours 5 years 37 9 21~12
3 hours 25 years 78 20 4'6 27
3 hours 100 years 136 34 77 41
FUTURE CONDITION:
1 hour 1 year 115 50 69 31
3 hours 5 years 115 43 59 27
3 hours 25 years
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160 55 81 41
3 hours 100 years 233 80 122 60
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IFUTURECONDITION
WITH REGIONAL RETENTION:!
3 hours 25 years 53 24 26 3
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for drainage ways and capacities for retention facilities,it is necessary
to carefully calibrate the computer model with the watershed.Although con-
tinuous flow gauging records were not available~we were fortunate to have a
21 year peak stream flow record as compiled by the U.S. Geological Survey for the
Upoer Munson Creek subbasin,designated as the ®-®series in the watershed
map,Figure 5.Only after acheiving a best match situation between this trial
watershed and the existing record,did we extend the analysis to the remainder
of this 3.5 square mile study area.
Saturated soil conditions.The computer model was found to be sensitive to
time based decay of the rate of sustained infiltration;one of many programmable
variables within this model.Observations show that for various watersheds,
rainfall over nearly saturated soil conditions,such as back to back wet weather
storms,produce disDorportionately larger runoffs than an isolated occurance
thunderstorm.To effectively model wet weather storms,we therefore utilized
saturated soil condit1oBs in the final analysis to account for this condition.
Programming for future land develooment.Surface water flows from future land
use conditions were analyzed by changing the physical watershed parameters.These
factors include a lower percent of imperviousness which results from roads,building
roofs,etc.Increasing overland flows and velocities reduce the surface retention
capacities and increase the velocities of runoff as it is removed from the surface
by gutters inlets,conduits and channels.Figure 6 shows the two watersheds broken
down into the nine major subbasins which were then extensively analyzed.Surface
water diversions from one basin or subbasin to another are shown in Table 4. In
general,these diversions have been projected as likely to occur due to:the
necessity of providing adequate drainage with continuing development;limitations
of gradient;potential errosive conditions and the effective restructuring of
points of discharges or as to promote efficient use of regional retention facilities.
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TABLE No.4
COMPUTER MODEL MODIFICATIONS FOR FUTURE CONDITIONS:
The computer model of the existing conditions was modified to accomodate
anticipated changes in drainage patterns as the study area urbanizes.
~1UNSON CREEK:
Area No.61:Modified to include diverted area directly tributary to Allen
Creek. Future condition to tnclude'cedd i t i onal 72 acre area in
Subcatchment a-rea 61 to form Subcatchment No.7.
Area No.76:Portion of Subcatchment Area No.76,approximately 10 acres,•to be div-e-rted to Allen Fork.
Area No.B2:Subcatchment Area No.B1 combined with No.82 to fonn new
Catchment Area No.B.
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Area No.IS
91,92,93:Subcatchment Areas combined to form Subcatchment Area No.9.
Area No.'s
94,95,96,97:Subcatchment combined to form Subcatchment Area No.6.
Area No.34:Subcatchment enlarged to include:aporoximate1y 10 acres
diverted area previously tributary to Allen Creek.
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ALLEN FORK:
Area No.'s
1,2,3,4:
Area No.'s
53,54,55:
Area No.IS
41 ,43,44:
Area No.'s
30,31-32,
33,34:
Subcatchment combined to form Subcatchment No.1.
Subcatchments combined to form Subcatchment No.5.
Subcatchments combined to form Subcatchment No.4.
Subcatchments combined to form Subcatchment No.3.
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Regional retention sites.Shown on Figure 6 are 11 different stream stations
at which either a runoff volume or peak flow analysis was performed.Twenty
potential locations for regional facilities were preliminarily evaluated for
regional cost and capacity of which 11 were retained for investigative modeling.
By testing several of these potential project locations at a time,using the
calibrated computer model,we were able to develop the most efficient and
effecti ve combi ne t ions .Variable parameters included pond capacity,and
discharge.Extent and duration of peak flows at the selected locations were
used to evaluate the hydraulic effectiveness and synchronization of the model.
The 25 year storm event was used for this important test evaluation process.
Summary of stream flows. A summary of stream flows for Allen Creek and Munson
Creek are shown in Tables 2 and 3 respectively.Estimated instantaneous
peak flows are tabled for nine models at stream channel locations,corresponding
to the major subbasins,shown in Figure 5 and 6. For each of the locations,
peak flows are estimated for the 1, 5,25 and 100 year storm events in three
different catagories:eXisting conditions,future conditions without surface
retention facilities,and future conditions with regional retention facilities.
Based upon the SWMM model peak stream flow for a suburbanized watershed without
stormwater retenti on facil iti es are si gnifi cantly greater than the exis ti ng
streamflow.Total direct runoff from a storm event can be expected to be 200%
to 300%greater after development.These transformations within the hydrologic
character of a watershed are best expressed in terms of peak stream flows and
fre~uency of occurance.
Evaluations and recommendations.Principally due to the pervious soil structure
and the lack of formal drainage system, the present land use serves rensonably
well in altering peak streamflow conditions.The primary purpose and benefit
of implementing regional retention facilities will be to hold this hydrologic
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system in balance,thereby preventing downstream property damage and detouring
degradation of the streamside environment.
With these considerations in mind,one of the more important evaluations
of a proposed regional facility should be its hydraulic effectiveness.In
addition to comparing instantaneous peak flows,average high water flows
should also be evaluated.Soil errosion is an on-going process which is
accentuated by lengthy periods of high streamflow velocity.
The recommended regional sites shown in Figure 6 were selected as the
favored location which could satisfy the hydraulic criteria in addition
to being cost effective choices.Tables 5 and 6 provide additional cost
and hydraulic information on the 11 sites.
Also included in the recommended regional program is the adoption of
designated drainageways.These drainageways would provide a planned collector
system of conduits and open channels which would assist in defining and imple-
menting the regional subbasin system. These drainageways would be improved
as made necessary by local developments or changes in land usage.By adopting
standards and requirements for these facilities,the City should be able to
exercise proper control in the development of this underground utility system.
•
TABLE 5
Estimated Construction Costs
City of Marysville Proposed Storm Retention Basins•
ITEM SITE SITE SITE SITE SITE
"A""B""C""0"liE"
•Elev.Water Table 66 107 195 50 250
Dam Height 4 11 6 11 '
Elev. Bot.Pond 63 102 195 50 250
Elev.Top Pond 67 114 203 55 260
Acre-Ft.Vol.6.9 5.5 9.1 7.38 6.8
Excavavation-Yds.3 5,000 11 ,000 14,700 14,700 7,200
•Pond Area:Ac .2.0 0.9 DAC 1.4 1.8 1.50
Imported Fill-Yds.3 a
Ac.Clearing/Grubbing 2.0 1.5
Rip-Rap 300 1,500
Dike Fill-Yds.3 2,200 1,200 500 7,200
Export Excess Soil-Yds.3 5,000 8,800 13,500 14,700
•COSTS
~1obil iza ti on $3,000 1 $5,000 $5,000 $5,000 $3,500
$20,000/Ac.Land Purchase 18,000 28,000 36,000 30,200•Dike Fil1/Comoact 4,400 2,400 1,000 14,400
Export Material 20,000 35,000 54,000 59,000
Clear/Grubbing 2,300
Excavation 15,000 33,000 44,100 44,000 21 ,600
Imported Fill
Rip-Rap 6,000 30,000
•Exit Orifi ce or Spi 11 way 2,000 5,000 3,000 2,000 15,000
Estimated Construction Cost:$40,000 $100,400 $142,500 $147,000 $117,000
Estimated Project Cost:(2)$50,000 $126,000 $178,000 $184,000 $146,000
•
1-Existing City owned land
2- Estimated project cost includes a 25%allowance for engineering,administration and
contingencies.
•
•
•
-17-
•
~.TABLE 6J
Estimated Construction Costs
•City of Marysville Proposed Storm Retention Basins
ITEM SITE SITE SITE SITE SITE SITE
"F""F-1 1I "G II IIH".IIH-l""1"
Elev.Water Table 98 70 74 91•Dam Hei~ht 5 7 5 5
Elev. Bot.Pond 84 98 68 74 91 49
Elev.Top Pond 92 104 75 79 100 51
Acre-Ft.·Vol.6.4 2.4 3.0 2.3 2.1 1.0
Excavafion-Yds.3 7,500 1,600 5,600 4,000 3,200
Pond Area:Ac.0.85 0.40 0.50 0.73 0.5 0.5•Imported Fil1-Yds.3 1,450
Ac.Clearing/Grubbing
Rip-Rep 100 700 320
Dike Fill-Yds.3 200 1,450
Export Excess Soil-Yds.3 1,400 5,600 4,000 3,200
•COSTS._-
Mobilization $2,000 $1,000 $1,500 $ 2,000 $1,500 $1,000
$20,000/Ac:Land Purchase 17,000 8,000 10,000 14,600 10,000 20,000
Dike Fill/Compact 400 3,000•Export Materia1
30,000 5,600 22,400 16,000 12,800
Clear/Grubbing 1,500 2,200 1,500
Excavation 22,500 4,800 16,800 12,000 9,600
Imported Fi 11 10,200
Rip-Rap 2,000 14,000 6,400
Exit Orifice or Spillway 2,000 2,000 3,000 1,500 3,000 10,000•Estimated Construction Cost:$75,500 $21,800 $55,200 $62,300 $35,600 $53,400
Estimated Project Cost:$ 94,000 $27,000 $69,000 $78,000 $45,000 $ 67,000
•(1 )Estimated project cost includes a 25%allowance for engineering,administration
and contingencies.
•
•
•
-18-
•
•
BIBLIOGRAPHY
Hendrick,Don.Personal Correspondence,May 29,1981,Washington State
Department of Fisheries.~
SWMM Users Manual.E.P.A.•Pearson,Herb.u.S. Coast Geodetic Survey,Tacoma.
•
•
••
•
•
•
•
•
Poertner,H.G.1981 ASCE Stormwater Management Seminar.
-19-
AFFIDAVIT OF PUBLICATION'
STATE OF WASHINGTON,
County of Snohomish,
ss.
No._
d for the State of Washington,
.ng at Marysville.
Jill E,Woodworth ..________________________, ,being first duly sworn
on oath deposes and says that he is the ~~~!~_t_~~_~_,_
of THE MARYSVILLE GLOBE, a weekly newspaper.
That said,newspaper is a legal newspaper which has been ap-
proved by order of the Superior Court in Snohomish County
June 18, 1962 in compliance with Chapter 213 of Washington
Laws of 1941, and it is now and has been for more than six
months prior to the date of the publication hereinafter re-
ferred to,published in the English language continually as a
weekly newspaper in Marysville,Snohomish County,Wash-
ington,and it is now and during all of said time was printed
in an office maintained at the aforesaid place of publication
of said newspaper.That the annexed is a true copy of a
Notice of City of Marysville
__.lli:.dinanc.e.._UIQ&_l2.3.3.l as it was
published in regular issues (and not in supplement form)of
said newspaper once each week for a period of ..one con-
secutive weeks,commencing on the ~t;.lL_day of t1.?.Y ,
19__8_~,and ending on the __.?.!=.!J.day of~~J:, 19__~~,
both dates inclusive,and that such newspaper was regularly
distributed to its subscribers during all of said period.That
the full amount of the fee charged for the foregoing publi-
t · . th f $37 •45 hi hp.Sl.lOn I!':.P.~lIm o., W IC amount has been
On 'he 26th da,:':';~~:8:'TY OF MARYSVILLE ORDINANCE __lt~
dlnance No.1233,entitled'' , the City Council of the City of Marysvlll
14~~g~DINANCE OF THE CITY OF MARYSVIL e paSSed Or-'e me this ~/~-
STORM THE MARYSVILLE MUNICIPAL CO LE ENACTING A NEW CHAPTER ---__\&2_'-:-'-~_
Said ~IATER DR.A:'NAGE CODE.DE ESTABLISHING AN ON-SITE ~~Cha:tern:4~~;consl~~~s;:et::ofrO~O;~~:rs~::~:~eCode'~~.~_...~~..~
14.15.010 Purposes
14.15.020 Definitions
14.15.030 Submissions of a Drainage Plan
14.15.040 Contents of Drainage Plan
14.15.050 Mandatory Requirements for All D I
14.15.060 Development In Criti I FI ra nage Improvements
14.15.070 Establishment of Re~l~nal o~:~I~~;:;~age and/or Erosion Areas
14.15.080 Temporary Erosion Controls .14.15.090 Fees
14.15.100 .Review and Approval of Plans
14.15.110 Inspections
14.15.120 Bonds and Liability Insurance Required
14.15.130 City Ass~",!Ptlonof Malnten'ance
14.15.140 RDet~oactlvlty Relating to City Maintenance of
rarnage Facilities~1·15.1S0 Maintenance of Drainage Facilities by Own
14'~~'117600 , AEPPllcablllt
y to Governmental Entities e~. .nforcement
The fUll text of said ordinance will be ·1 •
requests the same from the City Clerk.'mal ed,Without charge,to any person Who
Published:May 5,1982 .