Stormwater Control Measure Inspection & Maintenance Guide
The following StoryMap provides suggestions, best practices, and reference materials to guide the implementation of an SCM I&M program.
This StoryMap was developed by VHB as part of a Stormwater Control Measure (SCM) Inspection and Maintenance (I&M) guidance project funded by a MassDEP MS4 Municipal Assistance Grant awarded to the Charles River Watershed Municipal Stormwater Collaborative (CRWMSC). The purpose of this StoryMap is to provide a centralized resource to guide the implementation of an SCM I&M program for compliance with the 2016 Massachusetts MS4 Permit.
Table of Contents
This figure represents the ongoing cycle of SCM asset management and the steps to maintain compliance with the good housekeeping requirements of the MS4 Permit.
- Program Administration How to develop a team and associated resources to implement an I&M program
- Data Management Approach How to manage SCM data and associated I&M records
- Guidance & Training How to conduct SCM I&M activities and train personnel
- SCM Design Considerations How to design SCMs with maintenance in mind
- Regulatory Framework How to comply with MS4 and Wetlands Protection Act requirements
Program Administration
In order to create a successful inspection and maintenance program, municipalities must identify which individuals are responsible for which program elements and budget for the necessary SCM I&M activities.
Section Contents:
I&M Program Roles
The following sections outline key components and consideration for each of these roles.
Potential Consultants/Contractors*
*Please note, the list below is based on internet research and the companies listed are not a direct recommendation.
External consultants and contractors specializing in SCM I&M may be incorporated into the SCM inspection and/or maintenance team. Options include:
Several municipalities in the New England region use external contractors for SCM maintenance. Contracts can be developed to fit an individual municipality's needs. Example contract/bid language is provided below:
I&M Program Budget Estimation
There are multiple ways to achieve SCM I&M within a municipality, each with associated costs. Whether you use internal forces, contractors, consultants, or a mix, there are budgeting considerations. VHB has prepared a budget estimator template for this project to help estimate:
- Hours to complete annual SCM inspections
- Hours to complete routine maintenance
- Equipment costs
- Training costs
This estimator requires the user to input information (e.g., cost of personnel, number and type of SCM) and to evaluate/update cost information based on specific implementation needs.
Resources Related to Program Administration:
- O&M Considerations for Green Infrastructure (epa.gov)
- Considerations for SCM I&M program administrators, including planning, design, funding, training, equipment, and maintenance
- Elements of a Green Infrastructure Maintenance Business Plan (epa.gov)
- Outlines key elements of various models for SCM maintenance, including local (municipality) and owner-led models
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Data Management Approach
Municipalities need an SCM inventory that is easy to use, maintain, and integrate with inspection & maintenance forms.
This figure introduces the two key parts of SCM data management: an SCM Inventory and related Inspection and Maintenance Forms.
Section Contents:
SCM Inventory
Keeping track of all SCMs within your community is the first step towards creating an easy-to-use data management system. The inventory itself should be simple and easy to fill in to promote routine data entry. MS4 communities that rely on Geographical Information Systems (GIS) to manage existing datasets should continuing using it for SCM tracking. The table below lays out potential fields to include in an SCM inventory.
SCM ID | SCM Type | Installation Date | Location | Responsible Department or Manager | Inspection Frequency | Date of last Inspection | Additional Notes (and Attachments) |
|---|---|---|---|---|---|---|---|
Choose a naming convention for your SCMs and stick with it (just numbers: 9999, mix of numbers and type: surface9999) | Dropdown list | -- | -- | Dropdown list (DPW, Contractor, Combination, etc.) | Dropdown list | -- | Depending on where you choose to track SCM data, include fields for additional notes and attachments such as photos and forms |
Developed from CMRSC Template: sop9_forms.docx (live.com)
I&M Data Tracking
Along with the SCM inventory, a place to store records on I&M activities, agreements, and other forms is also needed. Whether you are using GIS or a non-spatial approach, such as spreadsheet tracking, similar information is needed.
Below are sample database tables from Recommended O&M Activity and Cost Reporting Parameters for Stormwater Best Management Practices Database , published by the Water Research Foundation:
Click to enlarge
Inspection records should be set up in a similar fashion, with SCM ID, date, inspector, and the inspection information itself. For more information on what should be included in inspection and maintenance forms, refer to the Guidance & Training section, which includes sample inspection checklists.
ESRI has also developed an ArcGIS solution for Green Infrastructure Inspections linked below. This solution can integrate with existing spatial databases and provides Survey123 forms to conduct inspections. The solution also includes a workflow for private property owners to conduct inspections through a community account and tracking dashboards to summarize work to date and follow-up maintenance activities.
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Guidance & Training
There are several key resources and trainings available on how to conduct SCM I&M, including frequencies of I&M, what to look for during an inspection, and important routine maintenance activities.
Section Contents:
Overall I&M Guidance
Summarized below are current guidance resources from various sources relevant to inspection and maintenance of SCMs.
The 2024 Boston Green Infrastructure O&M Handbook (Boston Water and Sewer Commission) was developed with a focus on the importance of long-term SCM I&M and provides the following information:
- Inspection and maintenance considerations (Chapter 2)
- Procedures for various SCM components (Chapter 3)
- Checklists for infiltration and bioretention practices, permeable pavement, and rooftop systems (Chapter 4)
The Minnesota Stormwater Manual wiki page includes an extensive resource catalog and recommended practices for operation and maintenance activities organized by SCM type.
Inspection Guidance
Inspection checklists can look different depending on your municipalities I&M program needs and what type of SCMs you have. Consider the following approaches to SCM inspection:
1. Simple Inspections
Using a simple inspection form can help ensure inspections get completed and information gets recorded. This approach can be helpful especially for privately owned SCMs or for inspectors with limited knowledge. However, this approach can make it difficult to understand specifics of maintenance follow up needs.
See the UNH Stormwater Center example of a Simple Visual Indicator checklist. The UNH Stormwater Center also has inspection and maintenance guidelines specific to certain SCMs.
2. SCM-specific Inspections
Inspection forms specific to SCM types can be useful to ensure each component of a specific SCM type is being visited and inspected. This can be helpful to guide inspectors to look for common maintenance issues of each SCM type. However, it can become cumbersome to manage multiple SCM inspection forms, especially in a GIS database.
See the inspection form templates from the Central Massachusetts Regional Stormwater Coalition . SCM inspection templates are available for various types of SCMs, including bioretention/rain gardens, constructed wetlands, extended dry detention basins, proprietary media filters, sand and organic filters, dry wells, and wet basins.
3. Component-specific Inspections
This approach includes completing separate inspection forms for separate components of an SCM, shown in the image to the right ( Image Source: Stormwater Innovation Center ). This can be helpful as it allows for a single inspection approach regardless of SCM type as the inspector is focused on SCM components, which can vary SCM to SCM. Components can include inlet, pretreatment, conveyance, overflow, and outlet structures among others. This approach also helps to communicate maintenance needs more clearly, especially for more complex SCMs. However, this approach requires inventorying multiple components of each SCM.
See MassDOT's sample SCM inspection form which utilizes this approach with an SCM form and separate Miscellaneous Component inspection forms.
Maintenance Guidance
Maintenance activities ensure that SCMs will continue to perform as designed. Recognizing when maintenance activities are routine short-term tasks versus major long-term projects can help you prioritize them and create a schedule that works for your I&M team.
The figure below provides an overview of different types of maintenance activities organized by frequency.
Along with understanding when different maintenance activities should occur at a large scale, it is important to understand which maintenance activities to perform on various parts of individual SCMs. The figure below provides a summary of routine maintenance activities for a common SCM basin.
For more guidance on maintenance activity frequencies and schedules for various types of SCMs, refer to the resources below:
I&M Trainings
Trainings for SCM I&M can take the form of thorough certification programs or quick videos for I&M crews to brush up on before a field visit. Review the trainings below to see what could work for your I&M team. Note that training is not required but is recommended to ensure that knowledgeable staff are completing I&M work.
The video below is an example of one of the brief training videos from the City of Pawtucket link above:
Pawtucket Pretreatment
SCM Design Considerations
SCMs should be designed and installed with maintenance and accessibility in mind in order to reduce costs and increase efficiency of I&M activities down the line.
Access to the SCM
During the design and construction phase of an SCM, ensuring access to the SCM for proper long-term inspection and maintenance is critical. Ensure:
- Enough space if available for maintenance equipment if needed
- Any easements/agreements are in place
- You have communicated upcoming I&M activities to landowners
- Subsurface SCMs have structures in place for maintenance access, such as a clean out port shown in the image below
Collection/Conveyance
Designing a successful collection system can make the I&M process a lot easier.
- Consider upstream and downstream hydrology/site attributes
- Consider the placement of collection components to minimize erosion and ponding (at low points, along a slope)
- Use anti-clogging devices throughout the collection system
Pretreatment
Pretreatment can collect certain pollutants and slow runoff before it reaches the SCM, simplifying maintenance activities.
Design considerations:
- Choose your pretreatment based on the expected pollutants at the site
- Sediment is more easily removed from a flat, hard surface than stone
- Typical components:
- Sediment forebay
- Filter strips
- Pretreatment swale
- Deep-sump catch basin
- Hoods on inlets
- Proprietary structure
- Trash racks and grates
- Pea gravel/stone diaphragm for filtering
Infiltration SCM Considerations
Requiring infiltration testing for proposed infiltration SCMs will ensure long-term function. Consider including infiltration testing requirements in project specification documents. Examples of this approach in practice include:
- MassDOT has a specification for infiltration SCMs, outlining testing and construction requirements. This specification is included on select projects as a special provision.
- As part of its Stormwater Review process , the Town of Winchester, MA requires infiltration testing for applicable SCMs. The Town also requires notification 48 hours prior of infiltration testing to allow for staff observation. The Town includes this in their standard conditions.
General Considerations
- Involve maintenance staff in selection and design
- Make sure the function of the SCM is communicated clearly (signage/manuals)
- Material selection is important (non-floating mulch, low-maintenance plants)
- Use qualified contractors for SCM installation
Refer to the New England Stormwater Retrofit Manual - October 2022 (snepnetwork.org) for specific design considerations based on SCM type
References:
Regulatory Framework
Click to enlarge
The Massachusetts MS4 Permit requires regulated communities to have procedures in place to ensure adequate long-term I&M of all SCMs. Within this permit, Minimum Control Measures (MCM) 5 relates to I&M of privately-owned SCMs and MCM 6 relates to I&M of publicly-owned SCMs. The sections below provide links to the permit language as well as resources to build municipal regulations to meet the permit requirements.
Section Contents:
MCM 6: Public SCMs
The MS4 Permit requires permittees to establish procedures and frequencies for SCM I&M. All SCMs must be inspected annually, at a minimum. See permit language to the right and also in the link to the Permit below.
Procedures for SCM I&M should be included in the Permittee's Operation and Maintenance Plan. A template for these procedures is included below.
The MassDEP Stormwater Handbook (Volume 2) provides maintenance requirements for SCMs. It is important to note these requirements are only for SCMs required as part of an Order of Conditions and are often inconsistent. Note: this handbook is set to be replaced with an updated version by the end of 2024.
For other guidance on SCM frequencies, see the Maintenance Guidance section of this StoryMap.
MCM 5: Private SCMs
Regulatory Language
The language from the MS4 Permit related to private SCM I&M is shown to the right. The Permit provides three separate options for compliance. Many municipalities have opted for the third option, which keeps the responsibility of SCM I&M on the property owner.
In addition, projects which require an Order of Conditions under the Wetlands Protection Act are required to develop and implement a Long-Term Operation and Maintenance Plan to ensure that stormwater management systems function as designed. Standard 9 in Volume 1 of the MA Stormwater Handbook explains the requirement for I&M:
Long-Term Inspection and Maintenance Plans
Documenting the requirements of long-term I&M in a plan, which is reviewed and approved by the municipality and includes a commitment by the property owner to implement the plan, is an important framework for success.
Recommended Components of an I&M Plan
- Summary of drainage infrastructure and BMPs on site
- Plan showing the locations of all stormwater practices including at a minimum a site plan, drainage plan, grading plan, landscape plan and detail drawings relevant to drainage infrastructure
- Description of I&M practices to be implemented for all drainage infrastructure and BMPs (broken out by BMP/structure type), including:
- frequency of inspections
- a requirement to photograph each BMP during each inspection
- actions to be taken to control invasive species
- Description and delineation of public safety features
- Estimated inspection and maintenance budget
- List of easements with a description of their purpose (i.e. drainage, access or slope encroachment, etc.) and exact limits of each
- Inspection checklists
- Maintenance checklists
- Blank inspection logs designed to record all relevant information
- Blank maintenance logs designed to record all relevant information
- Name of long-term I&M responsible party
- Contact information of long-term I&M responsible party (should be verified)
- Procedures for transfer of I&M responsibility
- Signed agreement to implement I&M Plan and either submit annual documentation of I&M or make documentation available upon request, depending on requirements
- O&M Sample Agreement Napa, California
- Template includes designation of responsible parties and a provision for cases where property owners fail to properly maintain their SCMs
Guidance for Private SCM Reporting Programs
VHB and the New Hampshire Seacoast Stormwater Coalition created a guidance manual to help MS4 regulated communities with implementing an I&M plan for private SCMs found in the link below. The guide includes templates for annual reporting, including a reporting form and enforcement letters.
The above guidance manual has attachments with information on facilitating I&M annual reporting, such as the fact sheet shown to the right. Education of private property owners responsible for SCM I&M is a key to success.
EPA has also created a self-certification process to streamline operation & maintenance of private SCMs. This process will require private SCM owners to self-certify that they are inspecting and maintaining their SCMs annually, reducing the amount of work that municipalities must do each year to ensure all SCMs are in compliance. The document linked below provides guidance on how to achieve this, as well as a self-certification form template in Appendix A that towns can give private SCM owners to fill out.
The Town of Wellesley is working to implement a BMP certification form based on EPA's template .
Wellesley's form will apply to property owner's subject to the Town's large house review and wetlands protection committee stormwater requirements. Additionally, the form will be used for properties with SCMs not be subject to the above reviews, but where property owners are applying for Stormwater Utility Credits .
In addition to requiring upcoming projects subject to the above reviews to complete self-certification Wellesley intends to conduct a review of record plans to identify projects in post construction with SCMs. Furthermore, the Town provides a spot on the self-certification form for property owners to attach total phosphorus credit calculations to support Phosphorus Control Planning efforts.
Annual self-certification renewal notifications will be sent through email annually. The Town of Wellesley's self-certification form is not currently live as of June 2024. However, upon release the form can be found on Wellesley's Department of Public Works Open Portal at the link below.
Additional questions can be directed to dpw@wellesleyma.gov
