Operation, Maintenance, and Inspection of Post-Construction Runoff Controls

Barry Tonning Tetra Tech

Key issues for O & M:

Requirements and challenges for a maintenance program

Maintenance program options

Major elements of a maintenance program

Tools and resources

EPA Phase II Requirements MUST: Ensure adequate long-term operation

and maintenance of BMPs. RECOMMEND: EPA recommends that you

ensure the appropriate implementation of the structural BMPs by considering some or all of the following: Preconstruction review of BMP design and selection; Inspections during construction to verify BMPs are

built as designed; Post-construction inspection and maintenance of

BMPs; and Penalty provisions for noncompliance with design,

construction or operation and maintenance.

BMP Maintenance Challenges Locating stormwater facilities Identifying responsible parties Lack of maintenance and

inspection staff BMP designs do not allow for

easy maintenance Lack of enforcement authority

and access Owners are unaware of

maintenance responsibility Proliferation of BMPs that

require intensive maintenance

Designing for better O&M Consider operation &

maintenance when siting BMPs and access roads

Specify performance criteria & O&M details for BMPs

Inventory info is a must! Designate O&M responsibility

to an entity that can handle it Trash cleanup & minor

maintenance can be handled by homeowner associations

Maintenance Program OptionsOption 1 – Municipality responsible

for public facilities; homeowners or businesses have responsibility for private facilities

Reduces costs Good option for small

communities with limited staff Community still responsible for

education, tracking, and enforcement (e.g., regular inspections)

BUT: Will private owners fulfill their responsibilities????

Maintenance Program Options

Option 2 – Municipality has full responsibility Uncommon due to expense Avoids legal proceedings Requires dedicated staff and funding BUT – better control & better operation/maintenance

Maintenance Program Options

Option 3 - Community has responsibility for public facilities and private facilities that discharge into public facilities

Hybrid of Options 1 and 2 – not as expensive Better control &

better O & M Requires dedicated

staff and funding

Case Study: Pierce Co. WA County created a stormwater

utility in 1996 All ponds, swales, culverts, and

etc. are deeded to county User fees pay for all county

O&M & monitoring work Homeowner associations

subject to additional fees if they own ponds, culverts, & etc. built before 1996

Ordinances and other info: see www.piercecountywa.org

Major Elements of a Maintenance Program

Preventive maintenance Operation and maintenance

ordinance specifying tasks Performance criteria, design

guidance, & inventory info Construction inspection

checklists, written reports Performance bonds As-built certification

O & M OrdinanceBasic elements commonly include: Requirements to inspect and maintain BMPs Easements or covenants for maintenance Identification of specific party or parties

responsible for maintenance, with penalties Authority of city/county to inspect BMPs Model O&M Ordinance and example maintenance

documents available from:

http://www.epa.gov/owow/nps/ordinance/

Construction inspection checklists

Some common design elements requiring inspection during construction include: Storage volume Emergency spillway (location, design,

dimensions, lining, etc.) Pipes (material, joints, alignment,

compaction, etc.) Embankments (slope, compaction, seepage

control, etc.) Elevations – design plans vs. as-built

Stormwater Observation Report Form (for As-Built

Certification)

City of Los Angeles

Planning and Program Implementation

BMP Tracking System Agreements and

Arrangements Easements Maintenance Plans &

Schedules Inspections

Major Elements of a Maintenance Program

Developing a Tracking System Provide an inventory of existing practices Track maintenance and inspection Streamline the inspection & maintenance process Provide documentation for legal action Relate design of BMPs to actual performance Use as a tool to develop program cost estimates Identify future retrofit opportunities

BMP database to track sites

Maintenance Agreements

Each agreement should contain: Routine Maintenance

Requirements – Who, What, How Maintenance Schedules – When Inspection Requirements Specifics on Access to BMPs Failure to Maintain Consequences Provisions for Recording the

Maintenance Agreement

Sample Covenant and

Agreement Form

Sample Operation and

Maintenance Plan

www.franklin-gov.com/engineering/STORMWATER/longtermplan.pdf

Maintaining the system Notification and reminders Inspection checklists P2 and education info Proprietary product guidance Compliance/enforcement

Major Elements of a Maintenance Program

Example of BMP Inspection Checklist

BMP Inspection Checklisthttp://www.hrstorm.org/BMP.shtml

Compliance assurance: how will

you ensure that BMPs are inspected,

maintained, and repaired when

needed?

Additional Maintenance Issues

Disposal of residuals from BMPs Confined Space Entry Vector control Invasive plants

Case Study: Montgomery County, MD

County’s Stormwater Facility Maintenance Program Program gives stormwater facility owners the

ability to transfer the maintenance and repair responsibilities for their stormwater structure to the County.

Funded by a Water Quality Protection Charge through County tax bills

Property owners still responsible for aesthetic maintenance (e.g., trash removal, landscaping, grass cutting, etc.)

www.montgomerycountymd.gov/content/dep/SFMP/home.asp

Montgomery County:Water Quality Protection Charge

Appears as line item on property tax bills Based on impervious surface (ERU) Charges for all residential and “associated

nonresidential property owners” ~ $3M for WQPC in FY 06

Montgomery County:Stormwater Facility Transfer Program

Property owners must record covenants and easements to allow County to perform maintenance of facilities

Facilities include: wet ponds dry ponds sand filters infiltration trenches oil and grit separators underground storage structures

Typical Maintenance Needs:Ponds/Wetlands

Tree growth on the embankment

Sedimentation Debris accumulation

(trash)

Blocked or clogged low flow outlet

Leaks in risers or barrel

Annual Maintenance Cost:3-5% of construction costs

Disposal of residuals

Not usually considered hazwaste

Used as landfill daily cover

Need to consider access for O&M

Typical Maintenance Needs:Filtering Systems

Standing water Clogged sand surface Broken observing

wells Vegetation growing

on media Inlet, outlet, or

underdrains clogged

Annual Maintenance Cost:~10% of construction costs

Typical Maintenance Needs:Infiltration Practices

Woody vegetation Sediment entering facility Sediment or debris removal

Inlet or outlet clogged Standing water

Annual Maintenance Cost:5-20% of construction costs

Typical Maintenance Needs:Oil/Water Separators

Sediment removal, oil/grease removal Debris accumulation, inlet/outlet clogged

Maintaining Your BMP: A Guidebook for Private Owners and Operators

Outlines basic maintenance & planning tasks

Basic types of BMPs Routine maintenance needs BMP maintenance costs http://www.novaregion.org/

bmp.htm

http://www.stormwatercenter.net/

For More Information The Low Impact Development Center

http://www.lowimpactdevelopment.org

Ctr for Watershed Protection’s Stormwater Center

http://www.stormwatercenter.net/

U.S. Environmental Protection Agency

http://www.epa.gov/owow/nps/urban.html

UW Center for Urban Water Resourceshttp://depts.washington.edu/cuwrm/

Center for Watershed Protection's web sitehttp://www.cwp.org/