1. Tim Schmitt, LimnoTech CWEA Fall Stormwater Seminar Dec. 14, 2016
Ensuring Adequate Data Collection to Take Credit for Non-Structural BMPs
Tim Schmitt, LimnoTech
CWEA Fall Stormwater Seminar Dec. 14, 2016
Thanks XXX.
Today I want to talk about non structural BMPs and some of the difficulties in taking credit for them for TMDL load reduction.

2. Outline Background Quantifying impact Non-structural BMPs in DC
Catch basin cleaning
Bulk vegetative debris removal
Street sweeping
Pet waste removal
I’ll start with some background on non-structural BMPs, focusing on what they are and how they are different than traditional structural BMPs
Then I want to focus on the methodologies for quantifying load reduction for non-structural BMPs and the data collection necessary to use these methodologies.
The I’ll move into some specific examples of non-structural BMPs being quantified in the District. I want to emphasize that there are a number of other non-structural BMPs for which quantification methodologies exist – like tree planting and buffer strips – but I want to focus on these and on the data collection challenges associated with them.

3. Non-Structural BMPs Programmatic activities
Asset cleaning/ maintenance
Restoration/creation of natural environment
Difficult to quantify?
Measure load in/load out?
Non-structural BMPs encompass a variety of activities, programs, and actions that are not built structures designed to treat stormwater, but which help manage pollutants
They include programmatic activities such as
Outreach,
Public education,
Good housekeeping, and
Pollution prevention
Asset cleaning and maintenance activities like:
Street sweeping
Catch basin cleaning
Restoration or management of the natural environment like tree planting
It may be difficult to quantify the impact of non structural BMPs because you can’t measure load in/load out like traditional structural BMPs to determine load reduction efficiency

4. Quantifying Impact of Non-structural BMPs
Quantifying impacts not always straightforward
Tree planting? Yes
Outreach? No
Measurable activities vs. measurable outcomes?
Outcome: load reduction
Example: public education meeting?
Quantifying impacts of non-structural BMPs on load reduction is not always straightforward
For example, there are protocols for measuring the impact of tree planting on load reduction, but how do you measure the impact of outreach?
So the question becomes, how do you translate measurable activities into measurable outcomes?
And remember, the measurable outcome must be in terms of load reduction
Example: how much load reduction credit can/should you take for holding a public education meeting?

5. Components Allowing Quantification of Impacts of Non-structural BMPs
Methodology
Amount of BMP implemented
Other factors
Data to use in methodology
Amount of BMP implementation
Additional data required by methodology
There are two components in quantifying the impact of non-structural BMPs: the methodology to quantify the impact, and the data to use in that methodology
With respect to the methodology, you have both the:
Quantification method for the amount of the BMP implemented; and
Quantification method for other factors used to translate units of BMP implementation into units of load reduction
With respect to the data to use in methodology, then, you need to quantify both the amount of the BMP implemented (and make sure that it’s in the right units), but also any other additional data you need to use in the methodology – and the latter part is usually the tricky part.

6. Potential Roadblocks Sufficient data? Pollutant types
Quantification of activities not typically quantified
Close coordination with others
Pollutant types
You can probably see from the emphasis I put on the previous slide that there are a lot of potential pitfalls or roadblocks in trying to quantify nonstructural BMPs. First, even when there’s an approved methodology, there may not be sufficient data to use it…
One reason may be that the method may require quantification of activities (or aspects of activities) that are not typically quantified – for example, the amount of material cleaned out of individual catch basins or the number of bags used at pet waste cleanup stations.
Second, you may need to go to other agencies/departments outside MS4 program to collect the data, and this may cause its own issues
Another issue is the type of pollutant that can be quantified. For the District, there are many TMDLs for pollutants other than nutrients and sediment, and there is not much information of impacts associated with reducing other pollutant types

7. Potential Roadblocks Issues for data collection Agreements Priorities
Data collection requirements/protocols
Manpower
Funding
Training
Tracking
Reporting
Potential issues with coordinating with departments/agencies for data collection
Problems developing MOUs to make sure that the data collection gets done;
Conflicting priorities – does the data collection agency give this effort the same priority that you would?;
New/additional data collection requirements/protocols;
Lack of manpower, funding or training for the agency doing the data collection;
Incompatible tracking between what the data collection agency collects and what the MS4 program needs. For example, are the assets called the same thig in different systems so they can be identified? This is slightly outside the realm of getting credit for BMPs, but in the District, the Inspections Branch uses a different system to track when a BMP has been inspected than does the Stormwater Branch, and it’s difficult for those system to talk to each other.
Inconsistent reporting – for example, in the District, there were some inconsistencies in how many road miles were reported swept on individual sweeper routes vs. how many road miles were even in those routes

8. Question: How Do You Take Load Reduction Credit for These BMPs?
Quantification method
Expert Panel?
Others?
Collect data
Existing data sufficient?
Update data collection methods?
Pilot studies?
Who does data collection?
Apply method
Documentation
Report
What’s the process for taking load reduction credit for these BMPs?
First, you need to identify a methodology for quantifying the BMP impact.
For many of us here in the Chesapeake Bay region, that would involve checking to see if there was a methodology approved by a Chesapeake Bay Expert Panel. That would allow taking credit towards Chesapeake Bay TMDL load reductions. But for other local TMDLs, there may be other methods out there that would allow you to propose load reductions for other pollutants.
The next step is to collect data necessary to use the chosen method. You may need to determine if you already have sufficient data to use the method or whether you need to do new data collection. You may need to develop pilot studies to refine that data collection method. Finally, you need to identify who will do the data collection.
Next, you need to apply the method, do the calculations and determine the load reduction. You need to make sure that you document all of your steps, because that’s an important part of the crediting process.
Last, you report all of the information to the regulatory agency.

9. BMPs with Crediting Methods Proposed in Washington, DC
Approved
Collection system cleaning
Catch basins
End-of-pipe
Street sweeping
Proposed
Pet waste cleanup
There are a number of non-structural BMPs that have been proposed for use for credit in Washington, DC, including street sweeping, collection system cleaning, and pet waste cleanup. Several of these have methods approved by Chesapeake Bay Expert Panels, but one does not, and I want to talk about each of these BMPs in a bit more detail.

10. Catch Basin Cleaning Credit
Approved
Load per catch basin cleaned
Steps:
Mass on annual basis
Convert wet mass to dry mass
Multiply by nutrient enrichment factor
Let’s start with catch basin cleaning. This is something that a lot of municipalities do, and it has a crediting methodology approved by an Expert Panel, so it seems like a natural fit to claim this for credit. But the tricky thing here is that the required data for claiming credit may be difficult to get.
This BMP is quantified as the actual load of pollutants removed per catch basin cleaned, and it is determined using the following steps:
First, the actual wet mass of solids/organic matter captured and disposed by storm drain cleaning practice are measured
Next, this wet mass is converted into a dry mass
And finally, the dry mass is multiplied by a nutrient enrichment factor to get loads of TN, TP and TSS removed.

11. Catch Basin Cleaning in Washington, DC
Conducted by DC Water
Data collection/reporting inconsistent
Formalized data collection
In Washington, catch basin cleaning is done by DC Water under an MOU with DOEE. DC Water does both catch basins in the combined area, where it holds the permit, but also in the MS4 area, where DOEE is the permit holder
Historically, data collection/reporting has been inconsistent -
New methodology has sparked formalized data collection effort

12. Catch Basin Cleaning Quantification
App to quantify percent filled for each catch basin
Quantification of volume removed
Also tracks ID
Location of catch basins in different watersheds
Permit requires annual catch basin cleaning
Catch basin cleaning optimization study
DC Water developed app to quantify percent filled for each cleaned catch basin cleaned
Allows quantification of volume removed for each catch basin
Different catch basin configurations require evaluation of standard engineering details to determine volume of different catch basin types
App also tracks ID of each catch basin
Allows location of catch basins in different watersheds for “local” TMDL credit
Permit requires annual catch basin cleaning
This is “baseline”
Catch basins cleaned more than once annually are considered additional load reduction
Draft permit requirements require catch basin cleaning optimization study

13. Bulk Vegetative Mass Removal
Credit for removal at outfalls
Identical to catch basin cleaning
District trash traps capture bulk vegetation
Trash TMDL requires quantification of removal
Expert Panel to Define Removal Rates for Street and Storm Drain Cleaning Practices allows credit for removal at outfalls
Method identical to catch basin cleaning method
District has trash traps that also capture bulk vegetation
Anacostia Trash TMDL requires quantification of removal at trash traps

14. Quantifying Bulk Vegetative Mass Removal
Trash traps at outfalls
Modify monitoring agreements
Monitoring done by non-profits
Current focus on quantifying trash
Identify trash traps at outfalls
Modify monitoring agreements to include quantification of bulk vegetative mass
Monitoring currently done by non-profits
Current focus on quantifying trash
Need to add quantification of bulk vegetative mass to procedures
Logistical issues
Already being done in some cases

15. Future Directions for Quantifying Bulk Vegetative Mass Removal
Refine methodology
Use a “discount factor”
Debris from both sewer system and overland flow
Credit for “local” TMDLs
Leverage permit requirements
Refine methodology for measuring wet mass of bulk vegetative debris
Use a “discount factor” to quantify bulk vegetative debris from instream trash traps
Vegetative debris from both sewer system and overland flow
Use for credit for “local” TMDLs
Leverage permit requirements for trash monitoring

16. Street Sweeping Approved methodology Data collection challenges
Data collected by DPW
Reporting inconsistent
Departments working for consistency
Methodology approved by Expert Panel
Data collection challenges in the District
Data collected by Department of Public Works (DPW)
Reporting inconsistent
Different reporting for different types of roads
Difficulty getting spatial data for routes swept
Reported mileage swept data inconsistent with route lengths
DOEE and DPW working together to make reporting consistent

17. Pet Waste Removal Proposed method by CWP Account for behavior changes
Increases in waste pick-up in dog parks
Bag usage
Proposed method developed by Center for Watershed Protection
Attempts to account for increases in pet waste removal through behavior changes
Increases in owners picking up after dogs when using dog parks
Quantified through pet waste bag usage

18. Difficulties in Applying Pet Waste Removal Methodology
Quantifying pet waste bag usage
Informal management
Behavior changes hard to quantify
Needs better documentation
Other factors
Pollutant load/unit of pet waste
Percent delivered to stream
Quantifying pet waste bag usage
Informal management of dog parks
Do not track bag usage
Bags may be donated
Behavior changes hard to quantify
Increase in owners picking up after pets at dog parks needs better documentation
Other factors need additional documentation
Pollutant load/unit of pet waste
Percent delivered to stream

19. Potential Methods for Tracking Pet Waste Removal in the District
DOEE tracks pet waste complaints
Geodatabase
Request for signs and bag dispensers
Pilot project?
DOEE Pollution Prevention groups tracks pet waste complaints
Tracked in geodatabase
Fulfills request for signs and bag dispensers
Potential for pilot project before and after putting up signs/bag dispensers

20. Summary Identify quantification methodologies
Quantify implementation and translate to load reduction
Data collection may be a challenge
Different data
New studies/pilots
Working with other agencies/departments
Existing tasks and relationships
Pay off - additional load reduction
Need to identify methodologies to quantify non-structural BMPs
Quantify amount of implementation and translate this to load reduction
Data collection may be a challenge
Different data compared to traditional structural BMPs
May require new studies/pilots
Other agencies/departments may be involved
Priorities
Budgets
Training
Reporting
Leverage existing tasks and relationships
Effort can pay off with additional load reduction

21. Tim Schmitt LimnoTech (202) 864-6821 tschmitt@limno.com
Jonathan Champion DOEE Stormwater Management Division (202)