Operation and Maintenance Private Property Owners

Stormwater Management Facilities

Operation and

Maintenancefor

Private PropertyOwners

Contents Page

INTRODUCTION: CARING FOR YOUR FACILITY 3

YOUR CONNECTION TO PORTLAND’S RIVERS AND STREAMS 4The Problem with Stormwater Runoff 4A Better Way To Flow 4What Else Is the City Doing?

INSPECTING AND MAINTAINING YOUR FACILITY 6Protecting Your Resources 6Inspection and Maintenance Logs 6

Sediment Removal and Disposal 8Vegetation Management 10Erosion, Bank Failure, Channel Formation 12Structural Deficiencies 13Ponding Water 14Pests 15Pollution You Can See or Smell 16Safety 17Paying for Maintenance 18

WHERE TO GET MORE HELP 19

OTHER WAYS TO PROTECT OUR RIVERS AND STREAMS 21

APPENDIX A: Legal Requirements -online

APPENDIX B: WILDLIFE HABITAT Maintenance - online

www.portlandonline.com/bes/index.cfm?c=34980

Stormwater Management Facilities

Operation and Maintenancefor

Private Property Owners

3 STORMWATER FACILITY MAINTENANCEENVIRONMENTAL SERVICES

Thank You

As the owner of a stormwater managementfacility, you are making a meaningful con-tribution to the health of Portland’s rivers

and streams. This handbook will help you main-tain your facility to make sure it performs thework it is designed to accomplish.

What Are Stormwater Management Facilities?Stormwater facilities are any combination oflandscape and structural features that slow, filter,or infiltrate (absorb) runoff on your propertyafter a rainfall. Types of facilities include vegetat-ed systems (planters, swales, ponds, wetlands,etc.), disposal systems (drywells and soakagetrenches), and structural systems (ecoroofs,

porous pave-ment and man-ufactured facili-ties). Piping,inlets and catchbasins are alsoimportant com-ponents thatneed adequatemaintenance toassure facilityfunction. All ofthese serve a

common purpose: controlling the quality andquantity of stormwater runoff from your site tohelp safeguard our valuable waterways.

Property OwnerResponsibilitiesProperty owners are legally responsible forinspecting and maintaining the stormwatermanagement facilities on their sites. Requiredmaintenance is outlined in the operations andmaintenance (O&M) plan for the facility. Thishandbook supplements that O&M plan, provid-ing additional information about what youneed to do, why, and how.

Operations andMaintenance PlanYou should be in possession of the O&M planfor any stormwater facility on your property. Inmost cases, the O&M plan is recorded with thecounty as part of your property title. If you arenot able to locate your O&M plan, callEnvironmental Services at 503-823-7740 toreceive a copy.

The steps we take today will greatly influencePortland’s environmental health and quality oflife for years to come. Individual actions canmake a big difference. Thank you for the sig-nificant part you and your stormwater manage-ment facility are playing.

If you need more information or have questions about your facility, callEnvironmental Services at 503-823-7740.

CARING FOR YOUR FACILITY


The Problem With Stormwater Runoff

When it rains in Portland, the stormwaterruns off impervious surfaces (such asroofs and paved areas) instead of soak-

ing into the ground. Conventional stormwatermanagement directs runoff into drains and pipesthat carry it offsite and eventually discharge itinto a river or stream. This approach has a number of harmful effects:

• Impervious areas generate large volumes ofrunoff relatively quickly. The increased vol-ume and speed of the runoff can cause flood-ing and erosion, destroy natural habitat, andcontribute to combined sewer overflows(CSOs).

• The runoff picks up a variety of pollutantsincluding oil, pesticides, metals, chemicals,and sediment that harm water quality and fishhabitat.

• During warm weather, the runoff absorbs heatfrom impervious surfaces. This increases thetemperature of the receiving waters, with neg-ative impacts on fish and other aquatic life.

• Less water is able to infiltrate into the ground.This reduces groundwater recharge, whichreduces summer flows in streams.

As Portland continues to grow and develop,these negative impacts will increase unless wedo things differently.

A Better Way to Flow The City of Portland and community membersare actively pursuing a variety of measures toreduce stormwater impacts. One importantapproach is to manage stormwater on the prop-erty where it originates.

Onsite stormwater management uses processesthat mimic nature. Onsite facilities allow runoffto soak into the ground, help filter out pollu-

tants, and slow theflow rate of runoffleaving your site. Thissignificantly reducesthe volume and pollu-tion levels in stormwa-ter leaving your prop-erty and ending up inrivers and streams.

Our homes, properties,vehicles, and actions all contribute to the prob-lem of urban runoff. Onsite stormwater manage-ment lets us all be part of the solution. Manyonsite measures can also provide a variety ofother benefits to property owners. For example,vegetated facilities can increase urban wildlifehabitat, add aesthetic value to the property andneighborhood, and decrease landscape mainte-nance and water use.

What Else Is The City Doing? Onsite management is just one component of acomprehensive citywide program to limitstormwater runoff impacts. Here are some othersteps the City is taking:• The City requires onsite stormwater manage-

ment for new construction and redevelopmenton public and private property.

• Natural areas, especially riparian areas adja-cent to rivers and streams, help filter out pollu-tion, control erosion, and provide shade, food,and habitat for fish and wildlife. The City usesa variety of measures to preserve these criticalareas, including development restrictions, landuse zoning requirements, land and easementacquisition programs, and incentive, cost shareand grant based programs.

• Millions of dollars are spent each year to helplimit environmental impacts from impervious

The onlineAppendix

discusses the federal and stateregulations that

require the City tocontrol stormwa-ter runoff. It also

identifies theCity’s legal

requirements for you as a

property owner.

YOUR CONNECTION TO PORTLAND’S RIVERS AND STREAMS


surfaces. The City restores streambanks; con-structs facilities to manage the quality andquantity of runoff entering the storm sewersystem; and builds, retrofits, or otherwiseenhances buildings, roads, parks, andstormwater drainage systems to improve conditions. Many of these projects are partnerships with private organizations orother public agencies.

• The City continually demonstrates and devel-ops new ways to operate and maintain streets,sewers, and facilities in ways that reducestormwater impacts.

• In partnership with numerous other organiza-tions, the City provides education, incentives,technical assistance, and project grant fundingaimed at reducing stormwater impacts andpromoting watershed health.

The Fish Connection

Chinook salmon and steelhead trout inthe lower Columbia River and upperWillamette River were listed in 1998

and 1999 as threatened species underthe federal Endangered Species Act

(ESA). These river systems include allrivers and streams within Portland.

Stormwater runoff has substantialimpacts on the water quality and habi-tat these fish depend on. By reducing

those impacts, we are taking directaction on behalf of the

threatened species, as well as otherfish and wildlife that are under stress.


Protecting Your Resources

It is essential to maintain your facility so it func-tions as intended and limits off-site environ-mental impacts. You are required to check your

facility regularly to determine maintenanceneeds. Routine inspection and maintenance canhelp keep overall maintenance costs low bydetecting problems early and avoiding largerepair or replacement costs.

This section identifies general guidelines on whatto look for and how to maintain your facility. Italso notes non-routine maintenance that mayrequire professional assistance. If you are unsureof what type of system you have, consult theStormwater Solutions Handbook for more infor-mation on approved stormwater managementfacilities.

Legal Requirements: Operations andMaintenance PlanAs a property owner, you are legally required tofollow the maintenance tasks and schedules spec-ified in the operations and maintenance (O&M)plan for your facility. This handbook supple-ments the O&M plan by providing additionalguidance. The O&M plan supersedes this hand-book if there are any discrepancies. If you need acopy of your site’s O&M plan, have any ques-tions or need more information, callEnvironmental Services at 503-823-7740.

Inspection Schedule: How often?It is recommended that you inspect your facilityat least:•Quarterly for the first two years

•Twice a year thereafter, and

•Within 48 hours of major rainfall events (morethan one inch of rain over a 24-hour period).

Some inspections are recommended more often,as noted in the following text.

For at least the first two years, you should con-duct inspections with the facility drawings andthe O&M plan in hand to help you understandhow the facility is supposed to function. Thissection will help you recognize signs that indi-cate diminished performance (for example, sedi-ment accumulation, vegetation die-off, or pond-ing water for more than 24 hours after a storm).

Inspection AndMaintenance Logs City Code requires you to keep inspection andmaintenance logs for your facility. In general,the quarterly logs should note inspection dates,the facility components inspected, and anymaintenance or repairs made. It is also a goodidea to track the rate of sediment accumulationand record visual observations about the facilityand its components. We encourage you to usethe sample log on the following page. If youhave a manufactured facility or have a mainte-nance contract with the manufacturer, assurethat their maintenance logs generally includethe same type of information and level of detail.If you are unsure whether your present logsheet is sufficient, call Environmental Services at 503-823-7740 to get review and approval for your forms.

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Facilities and System Components This Applies ToVegetated Facilities: ecoroofs, infiltration basins,planters, ponds, sand filters, swales, trees, vege-tated filters, and wetlands

Structural Facilities: catch basins, curb cuts,inlets, manufactured facilities, piping, sedimen-tation manholes, and vaults

Underground Infiltration Facilities: soakagetrenches, and drywells

Pervious Pavement

Impact on Facility PerformanceThe purpose of a stormwater treatment facilityis to remove pollutants, including suspendedsolids, by capturing sediment. Sediment caninclude dirt, leaves, and litter. These materialscan restrict or clog the facility. Timely removalof sediment will improve infiltration rates,water quality, and help prevent clogging andflooding.

What to Look For Check the depth of accumulated sediments. Sediment markers can be placed in the facility to help identify depths. Remove sediment when:Vegetated Facilities:• Sediment is 4” deep,• sediment depth is damaging or killing vegeta-

tion, or• sediment is preventing the facility from drain-

ing in the time specified in the O&M plan.

Structural Facilities:• At least once a year, or when• the basin is half-full of sediment.

Underground Infiltration Facilities andPervious Pavement:• Sediment is preventing the facility from drain-

ing in the time specified in the O&M plan.

What to DoOften sediment can be removed by hand. Largefacilities and underground facilities will need tobe cleaned with heavy equipment by trainedprofessionals.• Remove sediment during dry months when it

is easier to remove, weighs less, and createsfewer secondary environmental impacts(such as wet sediment running off the site).

NOTE: It is illegal to hose sediments through your system.

Doing it yourselfVegetated Facilities:• Use rakes and shovels to dig out

accumulated sediment.

• Avoid damage to existing vegetation.

• If sediment is deep, plants may need to beremoved in order to excavate sediment.

• Reseed and mulch disturbed areas to prevent erosion.

• Excavate sand or gravel and clean or replace.

Structural Facilities, Soakage Trenches andPervious Pavement:

• Catch Basins: Clean debris off the grate and bars. Lift the grate and use a bucket to remove water and a shovel to dig out sediment.

• Curb cuts, piping and other conveyance facil-ities: Use a shovel, router, air hose or otherdry method to clear sediment and debris.

• Soakage Trenches: Excavate sand or graveland clean or replace.

• Pervious Pavement: Remove accumulatedsediment from the surface with a dry broom,vacuum system, or other hand tools.

Sediment Removal and Disposal


Hiring ProfessionalsCleaning certain facilities will require professional assistance.• Underground facilities such as manholes,

drywells and manufactured facilities must becleaned by a vactor truck. Do not enter thesefacilities. They are defined by the OregonOccupational Safety and Health Division asconfined spaces and require proper certifica-tion to enter.

• Certain components such as collection basins,piping or pervious pavement systems mayrequire vacuuming with a vactor truck orstreet sweeping equipment.

DisposalWhen deciding how to dispose of sediment, youneed to consider the types of activities and pol-lutants on site. Sediment from commercial orindustrial sites is usually not considered haz-ardous waste. However, as the generator of thiswaste you are responsible for deciding how toproperly manage the removed solids.

Contaminated Water and SedimentCatch basins and stormwater facilities in areasused for chemical or hazardous waste storage,material handling or equipment maintenancemay collect the chemicals used in these activitiesfrom spills or via stormwater runoff. If youobserve an oily sheen, odors, discoloration, orother signs of pollution, hire a professional labo-ratory or sampling firm to assess whether thematerial needs specialized hauling, treatment ordisposal to comply with Oregon StateDepartment of Environmental Quality (DEQ)rules. If you need assistance deciding whetherthe solids should be managed as hazardouswaste, contact DEQ.

Non-Contaminated Water and SedimentDispose of the water in a sanitary sewer through ashop drain, sink, toilet or other appropriate drain.If the pollutant load is non-hazardous, water mayalso be spread across vegetation onsite.

Let the solids dry out, then properly dispose ofthem. Temporary erosion control measures may beneeded to contain the material onsite. Dry materi-als may be reused elsewhere on your site, may beeligible for reuse by others, or can be disposed ofat a designated solid waste facility.

Reducing Sediment Accumulation andPollution in Your Facility• Minimize outside sources of sediment, such as

eroding soil upstream of your facility.

• Sweep paved areas on your property regularly.

• Make sure chemical and waste storage areas arenot exposed to rainfall and stormwater runoff.

• Don’t let water from washing vehicles or equip-ment drain to your stormwater facility.

Additional ResourcesCatch Basin Cleaning, Material Handling andother Best Management Practices: Bureau of Environmental Services,Industrial Stormwater Section.www.portlandonline.com/bes/index.cfm?c=34618

Hazardous Waste: DEQ 503-229-5913, email [email protected],www.deq.state.or.us/wmc/hw/hw.htm

Sediment Removal:Look in yellow pages under “Sewage” or “Waste Disposal”


Facilities This Applies To Vegetated Facilities: ecoroofs, infiltration basins,planters, ponds, sand filters, swales, trees, vegetated filters, and wetlands.

Importance To Facility Performance Plants play an important role in stormwaterfacilities. They absorb water, improve infiltrationrates of soil, prevent erosion by stabilizing soil,cool water, and capture pollutants. Plants createhabitat for birds and other wildlife and provideaesthetic value to a property. Proper mainte-nance of vegetation improves the appearanceand performance of your facility.

What To Look ForWhen identifying maintenance needs it is helpfulto have a copy of your landscape plan, thisshows the plants you are required to have inyour facility. Facilities should be checked formaintenance needs quarterly for the first twoyears and twice a year after that.Facility needs maintenance when:• Areas of soil are bare.

• Vegetation is buried by sediment.

• Vegetation appears unhealthy or has died.

• Nuisance and invasive plants are present.

• Vegetation is compromising the facility’sstructure by blocking inlets or outlets, or rootsare intruding into a component of the facility.

• Dropped leaves and other debris are con-tributing to sediment accumulation or areblocking inlets or outlets.

What to DoMaintenance activities can easily be incorporatedinto existing site landscape maintenance con-tracts. Vegetation can be maintained with a for-mal or more natural appearance depending onyour preference.General Maintenance• Remove dropped leaves, dead plants, and

grass and other plant clippings. Plant debris

adds nutrient pollution as it breaks down,and can clog facility piping and reduce infiltration.

• Avoid using fertilizers, herbicides, or pesti-cides in the facility. These products add to thepollution problems the facilities are designedto remedy.

• Use mulch to inhibit weed growth, retainmoisture, and add nutrients. Replenish when needed. Ensure mulch does not inhibitwater flow.

• Irrigate all new plantings as needed for thefirst two years.

Caring for wanted vegetationFacility owners are responsible for maintaininghealthy vegetation and must replace any plantsthat have died or been removed.

• You are required to maintain vegetation to thedensity approved on your landscape plan orspecified in the City’s StormwaterManagement Manual.

• Replant with vegetation approved for use inthe original planting plan or from the recom-mended plant list in the StormwaterManagement Manual.

• Plant in late fall or early spring so plant rootscan establish during the cool, rainy seasons,before summer.

• Amend and aerate compacted soils beforereplanting by adding compost to increasenutrients and enhance soil texture.

• If plants are not surviving, determine the rea-son for the plant die-off. Survivability may be improved by planting vegetation bettersuited for the site conditions or by irrigatingmore. You may need to test planting bed soilsfor pH, moisture, and other factors such asnutrient levels, soil structure, and organicmatter content.

Vegetation Management


Mowing• Grassy facilities are designed for routine mow-

ing. Mow at least twice a year.

• Grass should be mowed to keep it 4” to 9” tall.Grass that is at least 4” tall captures more pol-lutants and is hardier. Grass over 10” tall isconsidered a nuisance by city regulations.

Nuisance and unwanted vegetation

• Remove nuisance and invasive vegetation,such as Himalayan blackberry, English ivy andreed canarygrass, before it goes to seed in thespring. Do additional weeding in the fall. A listof nuisance plants can be found in thePortland Plant List (see below).

• Immediately remove vegetation that is clog-ging or impeding flow into the facility.

• Remove potentially large and deep-rootedtrees or bushes when they might impede theflow path or compromise facility structures.

• Provide erosion control on any dirt exposed byvegetation removal.

WildlifeVegetated facilities create habitat, especially forbirds. The Migratory Bird Treaty Act protects allnative bird species. Birds and other animals willgenerally adjust to human activity. However,there are simple measures that should be taken to avoid disturbance:• Avoid maintenance during bird nesting

season from early March to late July. Pruneand mow during late summer. Many babybirds will spend some time on the groundafter leaving a nest.

• Walk the site before you do maintenance. Look for nests, burrows and animals in thefacility. Reroute around animal areas by atleast a few yards.

• A more detailed chart highlighting specificinformation regarding species you mightfind near or in private stormwater facilities canbe found online in Appendix B.

www.portlandonline.com/bes/index.cfm?c=34980

Additional ResourcesCity of Portland Resources:Naturescaping courses, native and invasive plant posters:www.portlandonline.com/bes/index.cfm?c=dcbec

Environmental Services Revegetation Program:www.portlandonline.com/bes/index.cfm?c=dffci

Portland Plant List (native and nuisance plants)www.portlandonline.com/shared/cfm/image.cfm?id=58951

Plant Identification:Native Plant Society: 503-460-3198, www.npsoregon.org/

Master Gardeners: www.orst.edu/extension/mg/

Native Plant Nurseries:Plant Native: www.plantnative.org


Facilities This Applies ToVegetated Facilities: ecoroofs, infiltration basins,planters, ponds, sand filters, swales, trees, vege-tated filters, and wetlands.

Importance To Facility PerformanceStormwater flowing through a facility can causeerosion. Erosion can increase sediment build up,clog outlets, reduce water quality benefits, addto pollution and cause facility components tofail. Eroded channels create an easy path forwater to travel down reducing the ability of thefacility to filter pollutants and infiltrate water.

What To Look ForAny area with erosion more than two inchesdeep needs maintenance.Signs of erosion and common locations:• The formation of flow restricting channels in

the bottom of the facility, around inlet pipesand curb cuts, or at overflows.

• Undercutting, scouring, and slumping alongbanks or berms.

• Channels and undercutting through checkdams. (check dams are small berms builtacross a facility to slow water and createsmall areas of ponding).

What to Do• Fill the eroded area with soil, compact it light-

ly, and cover with mulch, compost, seed, sod,or other erosion prevention materials.

• Plant banks with deep or heavily rootedplants to permanently stabilize soil.

• Plant the bottom of the facility with grass or grass-like plants to slow water and stabilize soil.

• Install or repair structures designed to dissi-pate energy and spread flow, such as splashblocks on downspouts, or riprap around inletpipes and curb cuts. See the StormwaterManagement Manual for requirements.

• If erosion continues to be a problem, consult a professional to determine the cause and a solution.

Erosion, Bank Failure, Channel Formation


Facilities This Applies ToMost stormwater facilities have some structuralcomponents. Some facilities such as vaults, dry-wells, and sediment manholes are completelystructural. In vegetated facilities, structural com-ponents often control how water enters, travelsthrough, or exits a facility. Common structuralcomponents include:• Inflow and outflow pipes, curb cuts,

and trenches.

• Valves, orifices, trash racks, and pipes.

• Concrete, metal, and plastic structures andcomponents such as curbs, retaining walls,manholes and drywells.

• Earthworks such as embankments, checkdams, dikes, berms and side slopes.

• Riprap and other flow spreading elements.

• Access roads, gates and signs.

Importance To Facility PerformanceThese elements need to be in good workingorder to route flows into a facility and for thefacility to function properly.

What To Look ForLook at the general condition of these elements.Do they need repair or replacement? Are theystill properly aligned? Look for:• cracks, scratches, dents, rust, or other condi-

tions of wear.

• loose fittings, broken or missing components.

• insufficient oil/grease for moving parts.

• appropriate gravel cover or bedding to sup-port the structures.

• misaligned parts or other impediments to thecomponent’s ability to still pass flow.

Maintenance• Immediately repair or replace any major dam-

age to prevent catastrophic failure. Thisincludes any structural component that iscracked, loose or askew. You may need toconsult a professional engineer or hire atrained contractor to design and perform anyrepairs.

• Minor damage such as dents, or rust spotsmay not need immediate replacement butshould be monitored.

• Maintain access to the facility by keeping theaccess route open and structurally sound,fence gates and vault lids oiled and locksfunctioning. Access must be available in anemergency.

Structural Deficiencies


Facilities This Applies To

Vegetated Facilities: dry ponds, infiltrationbasins, planters, sand filters, swales, and vege-tated filter strips.

Underground Infiltration Facilities: soakagetrenches, and drywells.

Structural Facilities: manufactured facilities,and pervious pavement.

NOTE: Some facilities are specificallydesigned to always hold water such as: wetponds, spill control manholes, and sedimenta-tion manholes.

Importance To Facility PerformanceMost facilities are designed to drain in a certainamount of time. This varies from 2 to 48 hoursdepending on the type of facility. This time isstated in the Operations and Maintenance planfor the type of facility. Ponding water is usuallya sign that the facility’s outlet is clogged or it isnot infiltrating properly.

What To Look For• clogging of overflows or outlets with debris,

trash or other obstructions.

• fine sediments filtering into the soil or otherfiltration media (like sand or gravel) that canprevent proper infiltration.

• water that has remained ponded for morethan 48 hours.

Maintenance

• For surface facilities, first try raking the topfew inches of soil to break up clogged sec-tions and restore water flow.

• Clean out overflows and outlets with handtools, if possible. Difficult or hard to accessblockages may require a professional con-tractor.

• Identify sources of sediment and debris toprevent them from entering the facility.Simple actions like sweeping a parking lotregularly can keep sediment out of facilities.

• Make sure the facility has enough vegetation.Vegetation absorbs water and roots helpkeep soil loose so it can infiltrate water.

For more thorough instructions on removingsediment, see the “Sediment Removal andDisposal” section of this handbook. Sedimentaccumulated in stormwater facilities may beconsidered hazardous waste and must be han-dled and disposed of properly.

If ponding still occurs, contact a landscapearchitect or engineer for more assistance.

Ponding Water


Facilities This Applies ToAll types of facilities

Importance to Facility PerformanceMosquitoes can breed in ponded or other stag-nant water. Vegetated areas can be attractivehabitat for rats, nutria, beaver, and a variety ofbirds and amphibians. While some species aredesirable, others can be public health or nui-sance concerns. In particular, mosquitoes andrats can breed quickly and cause a public healthhazard if not removed. The presence of pestsdoes not necessarily impact the ability of yourfacility to treat and manage stormwater butmay indicate maintenance needs, such as lack ofproper infiltration.

What To Look For• Check for mosquito larvae in any system

with open, slow, or non-moving waters -especially during warmer weather. Larvaelook like tiny wiggling sticks floating per-pendicular to the water’s surface.

• Look for nutria, rat, and other animal drop-pings year round. Also check for structuralindicators such as beaver dams and rodentholes and burrows.

What to DoMosquitoes• The best way to avoid breeding mosquitoes is

to prevent ponding water. Mosquitoes needstanding water to lay their eggs, and for theirlarvae and pupae to develop. Most stormwa-ter facilities are designed to drain in at least48 hours. If your facility is not draining prop-erly see the “Ponding Water” and “SedimentRemoval and Disposal” sections of this hand-book.

• As a temporary control for mosquitoes, thecounty or other licensed professionals canapply pesticides to kill mosquito larvae in thewater or adult insects in the air.

• Enclosed facilities, like ponds, may be eligibleto receive Gambusia fish (also known as mos-quito fish) from the county. Gambusia feed onmosquito larvae. See below for contact infor-mation.

RatsRats need shelter, food and water to survive.• Remove plant debris that may provide shelter

for rats from the facility.

• Remove fruits and nuts that fall to the ground.

• Fill in burrows.

• Trap and remove individual animals.

Other WildlifeOther non-native and invasive animal speciesmay take up residence in your facility. Contact theOregon Department of Fish and Wildlife (ODFW)to help identify these species and suggest removalprocesses. Permits from ODFW are required tocapture and relocate native wildlife.Some common non-native species are:• Opossum • Fox squirrel• Eastern gray squirrel • Eastern cottontail• Nutria • Egyptian goose• Bullfrog • Red-eared slider turtle• Snapping turtle

Additional ResourcesRats and mosquitoes:Multnomah County Vector ControlOnline: www.mchealth.org/vectorPhone: 503-988-3464 email: [email protected]

Other Wildlife:Oregon Department of Fish and WildlifeOnline: www.dfw.state.or.us/wildlife/Main Phone 503-947-6000 or 800-720-ODFW (6339)

Pests


Facilities This Applies ToAll types of facilities.

Importance to Facility PerformanceStormwater facilities often collect a variety oftrash and debris. Trash and debris, especiallyfloating debris, can clog pipes or treatmentmedia. It can also cause odors through decay orby collecting spilled or dumped materials.Stormwater facilities are designed to help pre-vent pollutants from entering rivers andstreams. Any visible water quality pollutantsmay wash out of the facility spreading the pol-lution problem.

What To Look For• Check monthly for Trash and debris.

Any unusual or unpleasant smells from sources such as:• Natural plant decay.• Dying plants trapped under sediment.• A spill or a leak (e.g., gasoline or sewage).

Visible pollution such as:• Sheens• Turbid (cloudy) water• Discoloration, or• Other pollutants on the surface of the water.

What To Do• Regularly remove trash and plant debris.• Remove accumulated sediment (see

“Sediment Removal and Disposal” in this handbook).

• Make sure inlets and outlets are not clogged.• Identify the source of trash, debris or pollu-

tant, such as a spill, leak, or illicit discharge.• If there is evidence of a spill or leak, contact

a professional laboratory or sampling firm to assess whether the material needs specialized removal, treatment, and disposal.Use trained professional staff for any cleanupand remediation.

Pollution You Can See or Smell


In addition to keeping the facility in good work-ing order, maintenance should also strive to meetsafety and aesthetic goals that benefit the com-munity and protect your site workers. Considerestablishing maintenance triggers and practicesthat respond to the following issues. Keep inmind the safety of both the employees whomaintain your facility and the general public.

What to Look ForSite ConditionsConditions, such as steep slopes, slick surfaces,and vegetation debris, can create a falling hazardto employees and visitors.

Public SafetySome facilities, such as ponds and wetlands, canbe “attractive nuisances” attracting undesirableactivity, vandalism, or use that could be harmfulto public safety. Consider the safety features nowin place at your facility.

What to Do• Use barrier plantings or fencing to bar entry

into the facility area.

• Install road bollards, lighting, and signage todiscourage illegal dumping.

• Avoid maintaining facilities in wet weather toreduce the risk of injuries from slipping.Always make sure that appropriate safety gear(e.g., harness, gloves, face shields, safety line)is used.

• For underground facilities, avoid entering any-thing defined as a confined space. Vaults, deepponds, manufactured facilities or manholes areexamples of confined spaces. These areasrequire special permits, training and entrytechniques. Some can be inspected andcleaned from above without entering. Alwaysuse caution when working with undergroundfacilities. You are legally required to meetOregon Occupational Safety and HealthDivision (OR-OSHA) requirements for suchactivities.

NOTE: Remember that any modifications youmake to the facility must also be addressed inyour site’s O&M plan.

Additional ResourcesConfined space entry:OR-OSHA (confined space entry requirements)503-229-5910www.orosha.org/subjects/confined_spaces.html

Safety


Specific maintenance costs depend on the char-acteristics of the facility, the site, and the areadraining to the facility. The general rule ofthumb is that annual maintenance costs will be 5to 10% of the facility’s total capital cost. Routine,scheduled maintenance can help keep overallcosts down by addressing problems before theyrequire major attention.

Financing MaintenanceYou need to determine how you will financeyour maintenance needs. A facility maintenancefund is recommended for both capital mainte-nance procedures (e.g., facility replacement andnon-routine maintenance, such as sedimentremoval, facility component repair or replace-ment, major replanting, or safety structure con-struction) and operating maintenance proce-dures (routine activities such as facility inspec-tion, debris removal, and vegetation manage-ment). For homeowner associations, this couldbe a portion of homeowner fees or a specificassessment.

How Much to Save• An average 5 to 10% per year of the facility’s

capital cost for annual routine maintenance.

• A percentage of the non-routine maintenancecosts per year (i.e. for sediment removal, veg-etation replacement) based on the needed fre-quency. For example, if the facility isdesigned to need mechanical sedimentremoval every five years, 20% of the total costshould be put aside each year.

• An additional 3 to 5% of the facility’s capitalcost per year for eventual facility replacement(based on the facility’s life expectancy). Mostof these facilities have a life expectancy of 25to 50 years.

Vegetated Facilities• Most required routine maintenance (excluding

major repair and replacement) is estimated tohave an annual cost of $200 to $600 dollarsper acre of facility, above current landscapemaintenance costs. Costs can vary dependingon the types and level of maintenance prac-tices used.

• The cost and intensity of maintenance activi-ties are usually higher during the two-yearplant establishment period. During this time,plants will need additional watering andplants that die will need to be replaced.

Paying for Maintenance


WHERE TO GET MORE HELP

City of PortlandFor information about:

The facilities and procedures in this handbook and the O&M plan for your facility: Bureau of Environmental Services-503-823-7740

The City’s stormwater program and requirements (including Title 17.38, the Stormwater ManagementManual, and other legal/regulatory requirements): Environmental Services - 503-823-7740www.portlandonline.com/bes/index.cfm?c=31892

Spills:Environmental Services - 503-823-7180 (24-hour pager response) www.portlandonline.com/bes/index.cfm?&a=36153&c=31020

Building permit requirements: Bureau of Development Services - 503-823-7300 www.portlandonline.com/bds/index.cfm?c=35883

Plants: invasive removal and native plantings:Environmental Services, Revegetation Program - 503-823-7740www.portlandonline.com/bes/index.cfm?c=dffci

Naturescaping for Clean Rivers Program - [email protected] www.portlandonline.com/bes/index.cfm?c=dcbec

Other Information SourcesProfessional maintenance services phone book references:Vegetation Management: • “Landscape Contractors”

Sediment Removal and Disposal:• “Sewage,” or • “Waste Disposal”

Facility Alterations:• “Landscape Architects” or• “Engineers - Civil”

Manufactured Facilities: • Find the specific manufacturer

Confined Space EntryOregon Occupational Safety and Health Division (OR-OSHA):503-229-5910, www.orosha.org/subjects/confined_spaces.html


Wildlife and PestsMultnomah County Vector Control (for rats and mosquitoes): 503-988-3464, www.mchealth.org/vector

Other pest issues:Look in yellow pages under “Pest Control”

Oregon Department of Fish and Wildlife Information about non-native and invasive animal species and removal processes: 503-947-6000 or 800-720-ODFW [6339], www.dfw.state.or.us/wildlife

Portland Audubon Wildlife Care Center Help with injured animals and animal identification questions:503-292-0304, www.audubonportland.org

Wildlife Habitat in or near Stormwater Facilities:See online Appendix B of O&M Guidewww.portlandonline.com/shared/cfm/image.cfm?id=124909

VegetationPlant Identification:Native Plant Society:503-460-3198, www.npsoregon.org

Master Gardeners:www.orst.edu/extension/mg

Native Plant Nurseries:Plant Native:www.plantnative.com

For information or to register forthe program

www.CleanRiverRewards.com503-823-1371

When you containstormwater on your property,you help protect rivers andstreams and you can receive adiscount on your stormwater bill.


OTHER WAYS TO PROTECT OUR RIVERS AND STREAMS

There are many other actions you can take to protect our rivers and streams.For more information, call Environmental Services at 503-823-7740 or visit www.cleanriverspdx.org

In Your Home or Business• Use nontoxic cleaners.

• Properly dispose of hazardous materials.

• Conserve energy: switch to compact fluorescent bulbs, turn down the heat, do the laundry with cold water, purchase energy-efficient appliances.

• Use water wisely: fix leaks, use low-flow showerheads, use only the water you need.

In Your Yard• Plant native vegetation.• Consider planting perennials versus annuals.• Sweep instead of hose.• Cover bare soil with mulch or plants.• Compost yard debris.• Disconnect downspouts (where appropriate).• Use drip irrigation.

In and Out of Your Car • Properly maintain vehicles.• Wash vehicles where water is recycled.• Drive less: use transit, bike, walk, or carpool.• Recycle motor oil.• Clean up spills or leaks.

In Your Community• Volunteer for tree planting, cleanup, stream restoration, or ivy removal projects.• Report spills and illegal dumping (call 503-823-7180).• Don’t litter, and pick up litter when you see it.• Pick up pet waste and put it in the garbage or toilet.

In Parks and Natural Areas• Stay on designated hiking trails and biking areas.• Keep dogs on leashes and away from the streambanks and water. Scoop up after them.

Printed on recycled paper.WS 0646 Rev July 2006

Documents

Operation and Maintenance Private Property Owners