Generating Water Quality Credits

​​Maryland Water Quality Trading

 

How do I generate credits?

  1. Meet Baseline requirements;
  2. Implement a CBP approved practice;
  3. Demonstrate a load reduction below the baseline;
  4. Submit a Cr​edit Certification and Registration form;
  5. MDE Reviews the documentation and determines certification
  6. Certified credits get published on Maryland’s Trading Registry​​
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Urban Stormwater

 

Baselines

In order to generate credits from non-point urban Stormwater and Alternative BMPs, credit generators must meet the baselines for credit generation highlighted in this section.

Permitted Stormwater – Municipal & Industrial

The baseline requirement to generate WQ credits for a permitted municipal source is the restoration requirement of the National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit. For these permits, this is expressed as a percent impervious area treated.

Non-permitted Stormwater

The baseline requirement to generate WQ credits for a stormwater nonpoint source is existing conditions.

Credit Generation

Once baselines are met, any additional approved BMP installed is eligible for credit. All practices implemented in this sector to generate water quality credits shall use assessment tools consistent with the CBP modeling tools and be accepted by MDE  to calculate tradable credits.

Credit Certification

If you are interested in certifying credits for either Permitted or Non-permitted stormwater please send the following documents to MDE Trading program Administrator via the email address provided at the bottom of this web page.

  1. SW Credit Certification and Registration Form 4.17.19.pdfSW Credit Certification and Registration Form 4.17.19.pdf
  2. As-Built or BMP Verification Form (Coming Soon!)
  3. Credit Calculation Sheet (Coming Soon!)
​​

Wastewater

 

Baselines

In order to generate credits from Wastewater Sector BMPs, credit generators must meet the baselines for credit generation highlighted in this section.

The baseline for a wastewater point source shall be determined by MDE based on a concentration or loading benchmark established in the wastewater point source’s discharge permit. All facilities that wish to participate in trading must obtain permits that include terms allowing them to do so.

Credit Generation

Performance credits generated by Wastewater Treatment Plant (WWTP) point sources shall be based on the individual plant’s performance as follows:

  1. Credits will be generated on an annual basis by subtracting the annual effluent nutrient load from the performance-based benchmark load.
  2. The annual effluent nutrient load will be calculated by using the end of the calendar year annual cumulative flow for the facility, multiplied by the actual effluent nitrogen, phosphorus, or sediment concentration converte to lbs/year.

Credit Certification

For wastewater point sources credit certification, please send the following documents to the MDE Trading Administrator. For a list of eligible practices see Tools and Resources.

  1. WWPS_Credit_Certification_Registration_Form4.17.19.pdfWWPS_Credit_Certification_Registration_Form4.17.19.pdf
  2. Spreadsheet for TN, TP, and TSS Performance Based Credit Loads Calculation
  3. Cover letter from the Authorized Individual for the facility applying for credits (Coming Soon!)

On-Site Sewage Disposal Systems (OSDS)

 

Baselines

In order to generate credits from On-Site Disposal Systems (OSDS), credit generators must meet the baselines for credit generation highlighted in this section.

Current baseline loads for nitrogen credit generation is 18.56 lbs/year for systems located in the Critical Area for the Chesapeake and Atlantic Coastal Bays, 11.60 lbs/year for a system located within 1,000 feet of surface water, and 6.96 lbs/year for all other systems.

Credit Generation

Best Available Technology (BAT) Upgrades

Nitrogen credit for an OSDS upgraded with nutrient removal technology is calculated by subtracting the load of an upgraded system from that system’s previous baseline load highlighted above.

Credit Certification

If you are interested in certifying credits for OSDS please send the following documents to the MDE Trading Administrator via the email address provided at the bottom of this web page. 

  1. On-Site Disposal System Credit Certification Form (Coming Soon!)
  2. BMP Verification Form (Coming Soon!)
  3. Aggregating On-Site Disposal System BMPs Spreadsheet (Coming Soon)

Oyster Aquaculture

 

Oysters_ChesapeakeQuarterly_2010.jpg
Photo Credits: Maryland Sea Grant/Michael Flynn

As a Chesapeake Bay Program (CBP) Best Mangement Practice (BMP), MDE is including oyster aquaculture in its Water Quality Trading Program. MDE has used the CBP expert Panel Report to help guide the credit generation and reporting process.

Baselines

As there is no specific pollutant goals for this practice, the baseline for generating credits is existing conditions.

Credit Generation

There are two ways to generate credits using this practice:

- Basic Credit: The basic credit requires that oysters harvested and sold should be an oyster class size minimum of 2". To determine the credits that were generate please see the example below.

- Enhanced Credit: This credit requires counting oysters by size and ploidy at several intervals to determine the quantities of oysters at various class sizes.

Credit Certification

The CBP's report also recommended certain criteria for reporting in setion 9.2 on page 67. MDE has adopted many of the criteria and is in the process of coming up with a form to collect that information.

All credits require a 3rd party verifier that will be legally responsible for the credits they verify. MDE is working with industry professionals and growers to come up with a process to approve verifiers in a way that will provide transparency and ensure that credits are being generated accurately.

  1. Aquaculture Credit Certification Form (Coming Soon!)Credit Certification Form (Coming Soon!)
  2. BMP Verification Form (Coming Soon!)
 
In Maryland, a credit is defined as 1 pound of pollutant reduction for the duration of one year. Credit generating practices must be ​​​verified and credits are not valid for sale until certified by the appropriate State agency and placed into the Chesapeake Nutrient Trading Registry (CNTR). MDE is responsible for stormwater, wastewater point source, on-site disposal (septic) system and oyster aquaculture credit certification.  Agricultural practices are certified by the Maryland Department of Agriculture (MDA).
 

Overall MDE Credit Certification Process 



For generation of Agriculture credits, please visit Maryland's Nutrient Trading site. (leaving MDE website)
 

Credit Adjustment Factors

All credits require Edge of Tide (EoT) adjustments, based on the load they contribute to the Chesapeake Bay, to make them consistent across different regions in the State.
 
A Reserve Ratio of 5% will be applied to each credit certified by the State. This will create a pool of credits that can be used to buffer credit losses elsewhere, or be retired as water quality improvement.
 

Exceptions for Public Funds

BMPs implemented with public funding can be used to meet baseline permit requirements but are not eligible for credit generation during their “funded lifespan” unless otherwise specified.
 

Contact Information

Please direct questions or comments to the MDE Water Quality Trading Program: mde.wqtrading@maryland.gov
 
Questions or comments related to agricultural credits should be directed to MDA's Trading Administrator: NuTrade.mda@maryland.gov