Maryland Department of the Environment

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Information about Submitting Water Quality Data for Maryland’s Integrated Report

 

A​nnouncements​​​​​​

Notice of Public Solicitation of Water Quality Data for the 2026 Integrated Report of Surface Water Quality in Maryland. 

 

The Maryland Department of the Environment (MDE) is currently requesting data for the 2026 Integrated Report (IR) of Surface Water Quality in Maryland. As part of the federal Clean Water Act, MDE submits a biennial Integrated Report to the Environmental Protection Agency (EPA) that provides information on both impaired and non-impaired waters within the State of Maryland. In order to provide the most comprehensive report, the Department relies on water quality data from a variety of sources including Federal and State agencies, local government agencies, researchers, students, and watershed organizations.


If your organization collected water quality data in Maryland within the past five-year period (January 1, 2019- December 31, 2023), please consider submitting your data. MDE is particularly interested in water quality data that are comparable to state water quality standards and criteria (e.g., dissolved oxygen, pH, turbidity, various toxics, benthic macroinvertebrate and fish community data). Other water quality data, including conductivity, nutrient species, chlorophyll, habitat conditions, and field observations may also be used to assess ambient water quality.


To submit data, please complete this 2026 Integrated Report Submittal Form and follow the appropriate data pathway. For additional information on the types of data accepted and how to submit data, please see MDE's webpage below. ​


Because the IR is a regulatory document, some data received may not be suitable for water quality assessments. However, the Department will track all data received and data submitters can contact MDE to inquire how their data were used and why.  Please contact Becky Monahan at Becky.Monahan@maryland.gov with any questions.

 


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How to Submit Data to MDE

 
2026 Integrated Report Data Solicitation

For the 2026 Integrated Report (IR) of Surface Water Quality, MDE is accepting data from January 1, 2019, to December 31, 2024. To be included in the 2026 IR, all data must be submitted by January 10, 2025. Data submitted after this date will be reviewed for the 2028 IR.


Data Submission Process:

Organizations interested in submitting data for the 2026 Integrated Report should complete the Information Form.


There are several pathways to submit your data:

  1. Organizations Working with the Chesapeake Monitoring Cooperative (CMC):
    • Please submit the information form above. MDE will pull applicable data from the Chesapeake Data Explorer on or around January 10, 2025. Ensure your data is up to date in the Data Explorer by contacting Liz Chudoba at lchudoba@allianceforthebay.org
  2. Organizations Submitting Data Directly to EPA's Water Quality Exchange (WQX):
    • Complete the information form above and include all relevant Organization IDs or Site IDs. MDE will retrieve the applicable data from the Water Quality Portal (WQP) on or around January 10, 2025.
  3. Other Organizations:
    • Fill out the information form where you can upload your data and metadata. Alternatively, you may email your data and metadata directly to Becky Monahan at Becky.Monahan@maryland.gov by January 10, 2025. For large datasets, a Google Drive sharing option can be arranged. Please include a brief description of your data and all applicable metadata, including Standard Operating Procedures (SOPs) or Quality Assurance Project Plans (QAPPs).

Important Notes:

  • The IR is a regulatory document; therefore, some submitted data may not be suitable for water quality assessments. Additionally, data pulled from the Chesapeake Data Explorer may fall under a different data tier for MDE assessment purposes. For more information, please refer to our MDE Data Quality Tiers section below.
  • The Department will track all data received, and data submitters can contact MDE to inquire about how their data were used and the rationale behind its use.

For any questions related to data submission, please contact Becky Monahan at 410-537-3947 or Becky.Monahan@maryland.gov.​


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Partnership with the Chesapeake Monitoring Cooperative

 

Since 2015, the Maryland Department of the Environment (MDE) has proudly partnered with the Chesapeake Monitoring Cooperative (CMC) to enhance our understanding of water quality across the Chesapeake Bay and its watershed. This collaboration helps ensure that more community and volunteer water quality data is used in assessing water quality for the Integrated Report of Surface Water Quality.


The CMC connects various monitoring groups and projects across the region, providing technical, programmatic, and outreach support. They integrate volunteer-based water quality and macroinvertebrate monitoring data into a centralized hub called the Chesapeake Data Explorer. This data is publicly available, making it easier for everyone to contribute their findings and share important information about our Maryland waters.


MDE is committed to incorporating more community and volunteer-collected data into the Integrated Report. Our partnership with CMC helps us reach a wider audience and ensures that the data we collect is of known quality. Together, we simplify the process of checking data quality and organizing it in one easy-to-use platform.  We encourage all community and volunteer monitoring groups to share their data for our Integrated Report through the CMC Data Explorer. Our partnership is here to support you in this process!


For more information about the Chesapeake Monitoring Cooperative and how you can get involved, visit their website: Chesapeake Monitoring Cooperative.​​

Background

 
As part of the federal Clean Water Act, the Maryland Department of the Environment (MDE) submits a biennial Integrated Report (IR) to the Environmental Protection Agency (EPA). This report provides essential information on both impaired and non-impaired waters in the State of Maryland. To create the most comprehensive report possible, MDE relies on water quality data from a variety of sources, including federal and state agencies, local government entities, researchers, students, and watershed organizations. ​​

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Data Quality Tiers

 

To evaluate data submitted for Maryland's Integrated Report, the Maryland Department of the Environment (MDE) initially used a two-tiered approach to data quality. For the 2020 Integrated Report, MDE reassessed this system to align more closely with the Virginia Department of Environmental Quality (DEQ) and the Chesapeake Monitoring Cooperative. As a result, the data evaluation process has been refined to incorporate three tiers of data quality.


MDE's data tiers may differ from those of the Chesapeake Monitoring Cooperative due to the regulatory framework of the Integrated Report. MDE's tiers are based on data quality and the authorized uses of the information provided to the agency. The tiers progress from Tier I to Tier III, reflecting increasing data standardization and more rigorous quality assurance and quality control (QA/QC) protocols. Definitions and uses of each tier are outlined below.​


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Tier III- Approved by MDE

 

Definition: Tier III data are legally defensible data that can be used for regulatory decision-making purposes.


Tier III data require an approval process through Maryland Department of the Environment (MDE), the Chesapeake Bay Program (CBP), or the Chesapeake Monitoring Cooperative (CMC).  To request Tier III approval, please contact Becky Monahan at Becky.Monahan@maryland.gov or Liz Chudoba at lchudoba@allianceforthebay.org.


Appropriate Data Uses:

  • List or delist waters (Category 2 or Category 5) on the Integrated Report (IR)
  • Assess waters for the IR
  • Support attainment purposes
  • Contribute to State data for Total Maximum Daily Load (TMDL) development
  • Include all uses listed in Tiers I and II

Requirements:

  • QAPP: Data must be accompanied by an EPA-approved Quality Assurance Project Plan (QAPP).
    • The QAPP must be approved every 5 years.
    • Click here for more EPA guidance on QAPPs.
  • Field Audit: A field audit of the sampling protocols must be conducted by the Chesapeake Monitoring Cooperative, Chesapeake Bay Program, or Maryland Department of the Environment.  
    • The field audit should be completed within the first year after the QAPP is approved (can be done anytime during the first sampling season).
    • The audit is valid for the entire QAPP performance period (5 years), unless a major change occurs.
      • If a major change occurs (e.g., updating program structure, changing monitoring protocols, significant personnel changes), a new QAPP must be submitted for approval, and a new field audit must be completed.
      • If a minor change occurs (e.g., adding or removing stations, equipment updates with similar equipment, minor personnel turnover), document it in the QAPP only.
  • Lab Testing:
    • For bacteria (E. coli and enterococcus) analysis done “in-house," NSI proficiency testing (PT) for both IDEXX and membrane filtration must be completed annually before sampling begins.
      • PT testing must be performed for each analyte intended to be Tier III (E. coli and/or enterococcus).
      • Certifications of acceptable results must be received by MDE prior to the start of sampling each year for the data to be documented as Tier III.
      • For more information on proficiency testing, visit NSI's website here.
    • All other lab analyses must be conducted by a certified or State-approved lab where lab audits are performed.
  • Assessment Methodologies: All information must be consistent with Maryland's Assessment Methodologies​

 

Note: Much of this text was adapted from Virginia DEQ and Chesapeake Monitoring Cooperative webpages regarding their Data Levels or Tiers.​​​

Tier II - Partially Approved by MDE

 

Definition: Tier II data are collected using a defined methodology but do not meet the requirements for Tier III data and are not used for regulatory assessment decisions (i.e., Category 2 or Category 5 of the Integrated Report). However, waters with this level of data may be placed in Category 3 of the Integrated Report, indicating that there are insufficient data to make a definitive assessment, but follow-up monitoring is necessary.
 
 Appropriate Data Uses:

  • Track performance of Total Maximum Daily Load (TMDL) implementation
  • Designate waters in Category 3 for the Integrated Report
  • Help identify stream segments that require assessments for water quality standards attainment
  • Serve as initial screening data for listing or delisting waters (Category 2 or Category 5) on the Integrated Report
  • Identify waters for follow-up monitoring by MDE  
  • Include all uses listed in Tier I

 
Requirements:

  • Data should be accompanied by a Quality Assurance Project Plan (QAPP) consistent with EPA guidance.
  • Field sampling and/or lab testing protocols or Standard Operating Procedures (SOPs) must be documented.
  • The monitoring method may be similar to MDE protocols but not fully approved due to differences in sampling or testing methodologies.

 

Note: Much of this text was adapted from Virginia DEQ and Chesapeake Monitoring Cooperative webpages regarding their Data Levels or Tiers.



Tier I- Not Approved by MDE for Assessment

 

Definition: Tier I data are collected using informal methodologies and do not meet the requirements of Tier II or Tier III data. However, they are of known quality and still contribute valuable insights into the health of the Chesapeake Bay watershed.​

Appropriate Data Uses:

  • Educational or outreach purposes
  • Providing location information on monitoring activities
  • Establishing baseline data
  • Notifying of possible pollution events
  • Assessing the general condition of surface waters in Maryland
  • Identifying waters for follow-up monitoring by MDE
  • Highlighting local community projects aimed at improving the health of the Bay watershed

Requirements:

  • No Quality Assurance Project Plan (QAPP) or Standard Operating Procedures (SOPs) required by MDE
  • Uniform methodology is recommended
  • QAPP, SOPs, and/or lab methods do not meet MDE quality assurance/quality control requirements
  • May include land use data, visual observations of water quality, or other data not consistent with Maryland's Assessment Methodologies

Note: Much of this text was adapted from Virginia DEQ and Chesapeake Monitoring Cooperative webpages regarding their Data Levels or Tiers.



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Parameters

 

Purpose of the Integrated Report:
The Integrated Report aims to identify and list waters that do not meet established water quality standards (refer to Code of Maryland Regulations 26.08.02). The primary parameters assessed for the report include pH, dissolved oxygen (DO), turbidity (measured in NTU), biological indicators, water temperature (continuous monitoring), and bacteria. It's important to note that Maryland does not have water quality criteria for some commonly monitored parameters, such as nutrients, suspended solids, or water clarity (Secchi depth) for nontidal waters.


Bacteria Monitoring Considerations:

Bacteria is a widely monitored parameter; however, its applicability for recreational criteria, particularly in non-beach areas, requires careful consideration. Before submitting bacteria data for the Integrated Report, please review our Fact Sheet: Considerations for Bacteria Sampling at Non-Beach Areas.


For questions regarding the use of bacteria data for the Integrated Report, please contact Becky Monahan at Becky.Monahan@maryland.gov

Additional Resources:

For further information about water quality standards, please visit MDE's Water Quality Standards Page. For more details on assessment methodologies, please visit MDE's Assessment Methodologies Page.​



Quality Control of Water Quality Datasets

 

Data quality in Maryland's water monitoring programs is governed by the agency's quality control framework, which includes Maryland Department of Natural Resources (MDDNR's) and MDE's Quality Management Plan, a Quality Assurance Project Plan (QAPP) for each monitoring program, field and laboratory audits, proficiency tests, and Standard Operating Procedures (SOPs). For water monitoring programs conducted under contract to the EPA, QAPPs must be approved by the EPA Regional or Chesapeake Bay Program Quality Assurance Officer before monitoring begins.


Each program's QAPP outlines data quality indicators by establishing quality control and measurement performance criteria, ensuring a systematic approach to assess and maintain data quality.


For local agencies, educational institutions, consultants, or community science organizations aiming to have their data used for regulatory decisions (Tier III data), the following are required:

  • A QAPP aligned with EPA guidance outlined in the Guidance for QAPPs.
  • A field audit of sampling protocols by the Chesapeake Monitoring Cooperative, Chesapeake Bay Program, or the Maryland Department of the Environment.
  • Use of certified or State-approved laboratories where audits are conducted, or submission of bacteria samples for NSI proficiency testing.
  • Information consistent with Maryland's Assessment Methodologies.

To ensure confidence in the data provided to state analysts, the quantitative aspects of the data must be well-defined.

Key Data Quality Aspects:

  1. Precision: How closely do measurements agree with each other? Are sampling, handling, and analytical processes consistently executed?
  2. Accuracy/Bias: How close are measurements to their true values? Are the results consistently above or below the true value?
  3. Representativeness: Do the sample data accurately reflect ambient environmental conditions?
  4. Comparability: How similar are results from different studies, locations, or times? Are consistent sampling and analytical methods used to ensure comparability?
  5. Completeness: Is the data collected sufficient for assessing water quality? Can it be combined with existing data for a comprehensive assessment?
  6. Sensitivity: Are methods sensitive enough to quantify parameters at or below regulatory standards, and what is the confidence level in these results?

While QAPPs, field audits, and lab audits/proficiency testing address many data quality aspects, there may be situations where best professional judgment is needed. Some issues may not have quantitative tests, and contributed data often lacks detailed quality assurance information. Analysts typically conduct a subjective review of available monitoring program documentation and data. Once the data quality is deemed acceptable, the dataset undergoes a more quantitative review.​

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Water Quality Data Review

 

Assessment of Designated Uses in Maryland's Water Quality Programs

The designated uses defined in the Code of Maryland Regulations are evaluated using a limited set of field and analytical measures. Key parameters include water temperature, dissolved oxygen, pH, turbidity, water clarity (Secchi depth or light extinction), acreage of estuarine grasses, ammonia levels, biological integrity, and specific bacteria levels. While measures of nitrogen and phosphorus (nutrients) are monitored, they are not yet defined in terms of criteria. However, exceedances in dissolved oxygen or chlorophyll a criteria, along with nuisance algal blooms, are often linked to elevated nutrient levels. Metals and both inorganic and organic parameters are not routinely measured due to high analysis costs and the low likelihood of finding these substances at levels exceeding criteria, except in special studies or discharge permit requirements. Specific toxins, such as mercury and polychlorinated biphenyls (PCBs), are monitored through MDE's fish and shellfish programs.


Data Review Process

Water quality datasets used for assessing designated uses are first evaluated based on the corresponding QAPP or other reports that outline monitoring objectives and quality control measures. Key steps in this review include:

  • Sample Size and Distribution: Assessing whether the sample size is adequate and analyzing data distribution, including identifying outliers or errors.
  • Spatial and Temporal Distribution: Evaluating how data varies over space and time.
  • Censored Data: Examining any censored data and field notes for unusual events (e.g., storm events) that may impact data quality.
  • Seasonality and Correlations: Analyzing data for seasonal trends and known correlations (e.g., between conductivity and salinity). Censored data may be excluded from analyses if necessary.

Alternative Assessment Approaches

Not all water quality criteria assessments follow this methodology. Some assessments are conducted by other state programs using peer reviewed or specific methods and these results are not re-evaluated. Examples include:

  • Assessment of algal samples
  • Maryland's probabilistic non-tidal living resource survey (MD Biological Stream Survey)
  • Fish kill and bacterial assessments
  • Bathing and shellfish harvesting restrictions
  • Toxic contaminants in fish tissue, shellstock, and sediments

Additionally, some assessments are conducted by external agencies such as the Virginia Institute of Marine Science, MD DNR, Versar, Inc., Old Dominion University, and EPA's Chesapeake Bay Program. In these cases, assessment methods are peer-reviewed, and results are submitted to the state without further re-evaluation. Examples of such assessments for Maryland's Chesapeake Bay and tidal tributaries include:

  • Benthic community criteria
  • Aquatic grass coverage
  • Water clarity
  • Dissolved oxygen levels

Innovative Approaches and Modeling

MDE supports the integration of computer models and innovative methods in water quality monitoring and assessment. The Chesapeake Bay model plays a crucial role in developing loading allocations, evaluating the effectiveness of best management practices, and guiding implementation efforts. Various modeling approaches are also utilized in the development of Total Maximum Daily Loads (TMDLs). Given the high number of biological impairments listed in Category 5 of the Integrated Report, Maryland is increasingly relying on land use analyses, GIS modeling, data mining, and other innovative techniques to identify stressors, define ecological processes, and develop TMDLs.​


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Need Technical Assistance for your Monitoring Program?

 
MDE and its partners are available to assist your organization with monitoring program design to ensure that your objectives are met and that state data needs are addressed. For more information, please contact Becky Monahan at Becky.Monahan@maryland.gov.​​

For additional IR information, please visit MDE’s Integrated Report Web page.​​​​

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Maryland Department of the Environment
1800 Washington Blvd
Baltimore, MD 21230