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Monitoring Our Waters

The water quality monitoring program is the cornerstone of the Department of Environmental Protection's (DEP) entire watershed program. Water quality monitoring includes:

Image of DEP interns learning to monitor wildlife.
Each summer, DEP hires interns to help
with monitoring streams.

 
  • Assessments of the biological community living in our streams and waterways

  • Assessments of the structure, flow, and physical condition of the stream itself

  • Instantaneous water chemistry and testing

 

Stream monitoring supports stream resource management in the County in many ways:

 

Where is the Pollution?

Streams are often at the receiving end of rainfall (stormwater) runoff from land surfaces and local stormwater drain-pipe systems. Stormwater pollution, as well as sewage from leaky sewer lines and contamination from landfills, can shock a stream system for a brief period. But if these influences are persistent and repeated, they can degrade streams and the aquatic habitat for insects, fish, stream salamanders, and other biological communities.

 

Where is DEP Monitoring?

All County watersheds are monitored in detail once every 5 years according to a defined schedule. The map below illustrates the areas to be monitored in 2014 and 2015. The streams in Special Protection Areas are monitored every year.

Graphic of Montgomery County and where the biological monitoring team will perform studies in 2014 and 2015.

 

 

Image of summer interns and DEP staff working together to monitor streamsYou Can Help DEP Monitor Our Streams!

  1. Become a Volunteer Monitor

Several Montgomery County watershed groups have volunteer monitoring programs where County residents go into the field to collect data.  The data is then submitted to DEP to be incorporated with the County collected data.  To get involved with the monitoring and protection of a specific stream that is significant to you, view this list of local watershed groups and contact them to see if they offer volunteer monitoring.  Data can be submitted to askdep@montgomerycountymd.gov.

The following are user-friendly DEP data sheets and protocols that volunteers may use:

Habitat Assessment (PDF, 5.7MB)

Amphibian and Reptile Monitoring (PDF, 89KB)

  1. Become a Summer Intern

The DEP Biological Monitoring Program offers an excellent opportunity to train with County ecologists as they assess the health of watersheds in Montgomery County. These are unpaid internship positions, although they might be eligible for credit at universities and colleges that require an internship to graduate.  Learn more about the summer internship program. 

 

 

What Lives in Our Streams?

Montgomery County’s streams are home to a diverse community of plants and animals including hundreds of species of stream bugs, over 60 species of fish, almost 60 species of reptiles and amphibians, nine species of crayfish, and more than ten species of freshwater mussels. All of these unique animals live together forming the stream ecosystems throughout Montgomery County. 

I Want To Learn About:

 

 Fish

► Stream Bugs (Benthic Macroinvertebrates)

► Amphibians and Reptiles

► Crayfish         

► Freshwater Mussels

Aquatic Invaders

 

 

Biological Monitoring

Biological monitoring is the study of biological community structure and function to determine water quality. Biological organisms, such as aquatic insects, fish, and stream salamanders, rely on water—normal stream flows and supportive habitat conditions—to survive. Stream ecosystems have numerous biological communities that are interrelated, but some are easier to collect and analyze, and offer a better indicator of water quality, than others.

Biological indicators, includes evaluating the mix of species found, their life-stages, survival, reproductive stage, and health, to evaluate the condition of habitat in and around our waterways, as well as the quality of the water itself.

The Environmental Protection Agency (EPA) recommends the use of at least two biological groups to work as indicators of the overall health of any stream.

The County uses benthic macroinvertebrates and fish to assess stream conditions. Amphibians (stream salamanders) have been monitored since 2008 to provide another biological indicator. In addition, Montgomery County collects data on the presence and absence of freshwater mussels, crayfish, and invasive plants to determine the distributions of species in these groups.

 

What does DEP do with Biological Data?

Assessing waterbody health using biological assessments is fairly complicated. Saying that a water body is healthy because a certain type of organism was found there or that it is unhealthy because it does not support a certain type of organism is overly simplistic. DEP uses biological data in the following ways:

  • Data used in an Index of Biological Integrity (IBI)

The Index of Biological Integrity (IBI) uses multiple 'metrics' from the data collected to calculate a score for a waterbody. This involves taking various raw data about number of individuals and other characteristics about the species found in the waterbody and using a peer-reviewed methodology to "rate" the data collected from our streams with numeric indices developed from similar data collected from numerous similar streams. The results are then combined for an overall IBI score for the category being assessed (e.g., fish IBI score, benthic macroinvertebrate IBI score).

  • Data are used to develop an overall score rating for a waterbody

To develop an overall IBI score for a water body, DEP then combines the two species IBI scores (fish and benthic macroinvertebrates) and expresses the combination as a score whose maximum possible is 100% compared to the 'best' streams in Montgomery County.  These scores are translated into narrative rankings Excellent, Good, Fair, and Poor.  The IBI thus provides both a numeric score and a descriptive assessment of water body health.  

  • DEP uses data to track trends in watershed health over time

Because the County monitors all watersheds in the County at least once over a 5-year period, an overall snapshot of the condition of the County's watersheds, as measured by bioassessment, can be compiled every five years. This gives the County a good handle on watershed health trends over time.

 

Found an Animal?

If you found an animal in the wild, DEP recommends that you avoid picking up or touching the animal. Wild animals can be unpredictable and occasionally, dangerous if they feel threatened. In general, animals, captured from the wild do not make good pets and should be left alone. 

Of all the snake species in Montgomery County, only one, the Copperhead, is venomous. Harmless snakes such as the Northern Water Snake, Easterns Rat Snake, and Corn Snake are often mistaken for copperheads.

 

Is the Animal Sick or Injured?

If you found a sick or injured animal, call the police non-emergency number of 301-279-8000.

 

Want to Learn More?

Visit our Biological Monitoring webpage for information on how DEP analyzes its biological data.

Learn more about biological indicators of watershed health from the Environmental Protection Agency.

 

Stream Habitat

Stream habitat is one of the important factors that affect aquatic communities. Stream habitat describes the quality of the place or environment where the aquatic wildlife (fish, amphibians, stream bugs) live.

In Montgomery County, poor habitat is usually the most likely cause of a lack of aquatic species diversity, poor health, and decreased population sizes. Degraded in-stream habitat often results from uncontrolled storm water runoff and uncontrolled runoff from intensively grazed or cultivated agricultural land. Other reasons for poor stream habitat include altered stream flows, excess sediment, and a loss of surrounding trees and shrubs that help slow the erosion of the stream. Chemicals and pollutants also negatively impact stream habitat.

 

How does stream habitat affect the aquatic community and the environment?

Image of an excellent condition stream.

Stream habitat affects the aquatic community in many ways.

  • Too much sediment can smother bottom living organisms and communities by filling in the spaces between the stream bed material that the aquatic community needs for respiration and habitat space.

  • Lack of stream cover can impact the fish community by removing places for them to hide and rest.

  • Lack of clean stream gravel, clean running water and small pools removes places aquatic organisms need for egg laying and for nurseries for small fish fry.

  • Lack of riffles, pools and runs can impact separate life stages of aquatic organisms.

  • Murky, cloudy water prevents fish from seeing their food.

  • Too much sediment can cover the gills of aquatic insects affecting their ability to respire

 

In addition to habitat conditions in the stream, the condition of the adjacent stream banks and stream valley also affect the aquatic community. Some of the problems in the stream valley and stream bank include:

  • Uncontrolled access by agricultural animals into the stream causing siltation and muddy conditions.

  • Lack of trees on the bank to provide shade for cooler water conditions.

  • Stream bank erosion caused by mowing up to the edge of the stream.

Stream habitat is monitored by the DEP every time a stream is monitored for either aquatic insects or fish.

 

Stream Habitat Assessment Activities

Stream habitat is assessed in the field by trained biologists using a set of ten habitat features that rank important physical habitat attributes*. Each habitat feature is scored by two biologists who work together as a team to assess each specific habitat attribute. Habitat features are ranked into a category (i.e.: optimal, sub-optimal, marginal, or poor) using well defined criteria. All rankings are done through observation by the team, no direct measurements are taken.

The County reduces subjectivity and personal biases in using this visual based ranking method by having everyone on the monitoring team attend and successfully complete a calibration session. The habitat assessment is always done by 2 people so the final ranking represents a ‘compromise’ between the 2 staff that actually reduces variability among raters.

Each habitat parameter is given a score from 0 to 20. For cases where each side of the stream is assessed separately (e.g., stream banks), each side is scored from 0 to 10. There are a total of ten habitat parameters, so the highest possible score is 200.

The ten habitat parameters are as follows:

 

1. In-stream Fish Cover

  • Measures: quantity and quality of a variety of stable in-stream structures that provide cover for fish.

  • Natural in-stream structures include:

    • root wads

    • undercut banks

    • deep pools

    • boulder cover

  • Generally, the greater the variety of available cover, the better.

  • Artificial structures are also beneficial to fish populations.

 

Image of in-stream fish cover.

2. Epifaunal Substrate

  • Measures: quantity and quality of a variety of in-stream structures that provide living spaces for benthic macroinvertebrates.
  • Natural structures that increase the amount of dissolved oxygen (e.g.: riffles) are beneficial to the benthic macroinvertebrate community.
  • Heterogeneous structures that offer more variety of habitats (e.g.: various sizes of riffle substrate) are better than homogeneous structures that offer less variety. 
Image of epifaunal substrate.

3. Embeddedness

  • Measures:  the extent that riffle substrate (e.g.: gravel, cobble, and boulders) are embedded with silt, sand, or sediments.

  • The filling in with sediment in between rocks within the riffle reduces:

    • the amount of available habitat

    • the amount of oxygen that is produced by the action of water flowing through the riffle. 

Image of a stream with sediment filling the spaces between the rocks.

 

 

4. Channel Alteration

  • Measures: human-caused changes to the size and shape of the stream channel. (Example: many streams in urban areas were transformed into concrete to transport water or to restore banks.) 

  • Effects:

    • less suitable habitat for benthic macroinvertebrates and fish.

    • disrupts the aquatic communities with hydrologic impacts during high flows.

  • Artificial support structures for the stream banks (e.g.: rip-rap or concrete sidewalls) indicate the need for unnatural repair processes to streams that have already been damaged from the effects of urbanization. 

Image of channel alteration

5. Sediment Deposition

  • Measures: the accumulation of sediments within the stream channel

  • Sources of accumulation:

    • within the stream channel (i.e.: bank erosion)

    • from outside of the stream channel (e.g.: uncontrolled runoff from construction sites).

  • Effects of high levels of sediment:

    • an unstable environment that is continuously changing.

    • unsuitable environment for aquatic organisms, especially benthic macroinvertebrates. 

 

Image of sediment deposition.

6. Riffle Frequency

  • Measures: relative frequency of riffles within a stream compared with the width of the stream channel.

  • Importance of riffles:

    • are a high quality habitat for benthic macroinvertebrates.

    • more riffles means more available benthic macroinvertebrate habitat, which ultimately leads to a greater amount of food for fish. 

Image of riffles in a stream

 

 

7. Channel Flow Status

  • Measures: the degree to which the stream channel is filled with water.

  • Channel Flow Status is:

    • most closely affected by sediment deposition. (The more sediment there is in the stream, the more channel bars are formed, and the less the channel is filled with water.)

    • assessed by observing whether the water reaches from bank to bank or whether there are parts of the channel exposed.

    • most influenced by natural factors such as drought or flooding.

  • When there is less water in the channel, there are also fewer habitats available for aquatic organisms. 

Image of channel flow.

8. Bank Vegetative Protection

  • Measures: the amount of the stream bank (on the top and along the sides) that is covered by rooted (as opposed to overhanging) vegetation.

  • Root systems are important to help to stabilize the banks. (The greater the variety (i.e., trees, shrubs, herbaceous) of bank side vegetation the greater the stability of the bank.)

  • Native vegetation is much more desirable. 

    • Invasive exotic vegetation typically have shallow root systems that are poorly suited to stabilizing the soil and tend to crowd out more desirable native vegetation.

    • Some exotic vegetation (e.g., multiflora rose) that grows on top of the banks hangs over the sides of the bank and shades out vegetation that could have kept the banks stable.

    • Soil that is colonized by exotic vegetation is more prone to erosion than solids with a mixture of native vegetation.

    • Exotic vegetation tends to establish itself as a single dominant species crowding out a more desirable mixture of native vegetation which also is less stable.  

 

 

 

Image of bank vegetation.

9. Bank Stability

  • Measures: quality of bank side vegetation; closely related to bank vegetative protection.

  • The better the quality of bank side vegetation, the more stable the banks, and vice versa.

  • Unstable banks are also a source of sediment for the streams.

    • Signs of an unstable bank include dewatered and exposed tree roots, crumbling, sloughing, and exposed soil. 

Image of an eroding bank.

10. Riparian Vegetative zone and width

  • Measures: the transitional zone between terrestrial and aquatic habitats, usually corresponding with the flood plain area.

  • This is the only parameter that does not assess the condition of the stream itself, but rather the land immediately adjacent to the stream.

  • Importance of riparian zone:

    • serves as a buffer between the stream and the uplands.

    • shades the stream from thermal impacts.

    • slows down runoff to the stream to control erosion

    • traps nutrient runoff that would otherwise end up in the stream.

  • The wider the riparian zone and the more diverse the vegetation within the riparian zone, the better the condition of the stream.

  • A variety of predominately native vegetation within the riparian zone is of higher quality than a riparian zone dominated by a few species of mostly invasive exotic vegetation.  

 

 

 

Image of the riparian vegetation around a stream.

 

*Barbour and Stribling: Visual Based Habitat Assessment for Riffle/Run Prevalent Streams

 

Habitat Assessments Combined with Biological Monitoring

In-stream aquatic biological communities that are found to be impaired often are a result of degraded habitat. The table below describes four possible simplified scenarios relating biological condition to habitat condition. For example, if habitat is degraded, the biological community would be expected to be impaired. However, if the habitat is not degraded, but the biological community is impaired, then chemical contamination is suspected.

 

Generalized summary table to assist with explaining causes of biological impairment.
Biological Condition Habitat Condition
GOOD POOR
GOOD Not impaired Not possible
POOR Possible chemical contamination Habitat probably primary cause

 

 

Improving Habitat Quality with Stream Restoration

DEP restores streams with damaged habitat. For stream restoration to be most effective and remain in place, uncontrolled stormwater flows to the stream must be controlled which often involves retrofitting stormwater management ponds in sequence with the stream.

 

Physical Features of Streams

Taking different measurements of a stream channel over time will show how the stream channel changes (or remains stable). These changes are from natural and human-caused influences. The physical shape and features of a stream are necessary for aquatic organisms to survive. Diverse channel features can support healthy aquatic communities.

A carefully designed monitoring program can be an effective tool for tracking changes to the stream channel that result from both natural occurrences and changes in land use; both of which can have profound effects on the shape of the stream. Four measurements are frequently taken to describe stream shape, slope, and stream bed composition:

 

Image of DEP staff taking a cross section of a stream.
 
Taking a cross-section profile of the Northwest Branch.

 

1.  Longitudinal profile

a) Is a ‘slice’ down the stream.

b) Measures the slope of the stream, and lengths and number of riffles, runs and pools. 

c) Measurements over time can show trends in sediment build-up or erosion. Looking at these trends, we can see how disturbances such as floods or increased sediment amounts from land-use modify the channel bed.

 

2. Cross-section profile

a) Is a ‘slice’ across the stream.

b) Measures the shape of the steam bed, stream banks and the width of the stream channel. 

c) Measurements over time can show how the stream channel adjusts (widening, getting deeper or shallower) to accommodate the various flows and amounts of sediment it handles.

 

3. Channel sinuosity 

Image of DEP staff taking a pebble count of a stream.
DEP staff studying the physical features of the
Woodlawn Tributary.

a) Is the wavy shape of a stream.

b) Streams form into these wave-like shapes because of the amount of flow and sediment they carry.

c) Importance of measuring channel sinuosity:

1) It compares the stream’s adjustment to flow and bed load.

2) A stream that changes from a wavy shape to a straight stream is reacting to increased flow and bed load.

 

4. Pebble counts

a. Will measure the changes in the composition of the stream bed material over time.

b. For example, a stream may go from having mostly large, cobble size particles, to having mostly sand and gravel size particles as the stream fills in.

 

DEP performs extensive physical and chemical monitoring of streams, including stream flow, precipitation and stream channel surveys.  Learn more about this research and data on the Physical and Chemical Monitoring page. 

 

Water Chemistry

Chemical monitoring provides additional insight into the quality of water every time a site is visited. Occasionally, it is possible to detect a pollution event in a stream by taking note of pH, conductivity, temperature, and/or dissolved oxygen. After noting an abnormal reading, it is sometimes possible to walk upstream to investigate a potential pollution source.

 

Image of DEP staff monitoring a local stream for water chemistry.
 
Performing chemical testing on a stream​

Physical Chemistry Monitoring Activities

The following physical chemistry data is collected at every stream monitoring site:

  • pH 

  • Dissolved oxygen (DO) – the amount of oxygen in the water that is available to biological life, including benthic macroinvertebrates and fish

  • Conductivity 

  • Water Temperature 

  • Air Temperature

 

DEP performs extensive physical and chemical monitoring of streams, including stream flow, precipitation and stream channel surveys.  Learn more about this research and data on the Physical and Chemical Monitoring page. 

 

Requests for Data

Interested in accessing Montgomery County's stream monitoring data?  Individuals and groups can file a request for data by contacting the Department of Environmental Protection.

To request data, send an email to askdep@montgomerycountymd.gov with the following information:

  • Name, organization (if applicable), phone number, and/or email address

  • Type of data requested

  • Time frame requested

  • Explanation for use of data (helps to personalize the data request)

  • Preferred method of data retrieval (email, CD by mail, FTP, pick up CD or materials from DEP offices)

 

What Type of Data Can I Request?

 

Fish

Once numbers of individuals are summed for each species present at a stream site, a fish Index of Biotic Integrity (IBI) is calculated based on multiple metrics. The IBI is used to rank the stream in relation to reference stream conditions. To use biological data properly, water resource analysts generally compare the fish data (actually not the raw data but a multi-metric index based on the data) from the stream sites under study, to indices from stream sites in ideal or nearly ideal condition (often called a reference condition). Stream sites are then ranked against the reference condition. This helps DEP set priorities for watershed restoration and improvement.

The fish IBI is averaged with the benthic macroinvertebrate IBI to determine overall stream conditions.

Fish IBI metrics are listed below. A technical, peer-reviewed methodology is used to take raw data and develop them into an acceptable Stream Rating score.

 
Fish IBI Metrics

Total number of species

Total number of riffle benthic insectivore individuals

Total number of minnow species (cyprinidae)

Total number of intolerant species

Proportion of tolerant individuals

Proportion of individuals as omnivores/generalists

Proportion of individuals as pioneering species

Total number of individuals (excluding tolerant species)

Proportion of individuals with disease/anomalies

 

Montgomery County has tabular raw fish data and fish narrative summaries from 1994-present for most monitoring sites around the County. Also available are GIS coverages (or maps) showing fish conditions. Maps can be developed to order depending on the request. Submit a request for either raw data or data in maps.

The following tables provide an explanation of the datafields found in our raw tabular data:

 

Fish Data Table
Field Name Description
STATION The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+the two letter code for the subwatershed+ the single digit stream order code+ the sequential reach number.
SPECIES The official common name of the fish species collected during sampling.
SAMPLE_DATE The date the station was sampled.
PASS1 Number of specimens collected from the first sampling pass.
PASS2 Number of specimens collected from the second sampling pass.
ANOMALIES The total number of anomalies.
ANOMALIES_TYPE The number of anomalies found of a certain type + the two letter code for the type of anomaly found.
 
Fish Narrative Table
Field Name Description
STATION The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+the two letter code for the subwatershed+ the single digit stream order code+ the sequential reach number.
DATE The date the station was sampled.
SUMMARYSCORE The final IBI summary score (1-5).
NARRATIVE Descriptive word to describe the condition of the stream in relation to reference streams. Narratives are either Excellent (>4.5), Good (3.3-4.5), Fair (2.2-3.2), or Poor (<2.2).

 

 

 

 

 

 

 

 

 

 

 

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Benthic Macroinvertebrates

DEP collects a sample of benthic macroinvertebrates from the stream and returns to the laboratory for further sub-sampling. Individuals from the sub-sample are identified (usually to the genus level) and enumerated. From these data, metrics are calculated, scored, and then summed to obtain a final Benthic IBI score.

There are a total of eight metrics comprising measures of biological structure and function; each metric is scored either as a one, three, or five. The highest possible final score is 40 (5 x 8). To determine the overall stream condition, benthic IBIs are averaged with fish IBIs.

 
Benthic Macroinvertebrates IBI Metrics

Taxa richness (Total number of taxa)

Biotic index

Ratio of scrapers (Scrapers divided by (scrapers + filter feeding collectors))

Proportion of Hydropsyche sp. & Cheumatopsyche sp.

Proportion of dominant taxa

Total number of EPT* taxa

Proportion of EPT* individuals

Proportion of shredders

 

* EPT = taxa that are either mayflies (Ephemoptera), stoneflies (Plecoptera), or caddisflies (Trichoptera); aquatic insects that spend all of their juvenile or larval life stages instream.

To determine a narrative based on a final metric score, the following breaks are used. These breaks are determined by plotting reference stream benthic conditions.

 

Benthic Macroinvertebrates IBI Narratives
Score Narrative
> or = 36 Excellent  
26-35 Good  
17-25 Fair  
< 17 Poor  

 

 

Available Benthic Data

Montgomery County has tabular raw benthic data and benthic narrative summaries from 1994-present for most monitoring sites. Also available are GIS coverages (or maps) showing benthic conditions. Maps can be made to order depending on the request.

 
Benthics Data Table
Field Name Description
STATION Two letter stream code + two letter stream reach code + order (1-4) + reach number (01-99).
DATE The date the sample was taken.
TAXA Benthic macroinvertebrates are identified to family.
[#GRIDS] Number of grids sampled during subsampling routine to estimate benthic population sampled.
[#INDVS] Number of macroinvertebrate individuals sampled from subsampling routine.
EXCLUDE This is a taxa that is automatically excluded from further use in calculating metrics for IBI.
REPLICATE This is a repeat of another sample.
 
Benthics Narrative Table
Field Name Description
STATION The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+the two letter code for the subwatershed+ the single digit stream order code+ the sequential reach number.
DATE The date the station was sampled.
SUMMARYSCORE The final IBI summary score (1-5).
NARRATIVE Descriptive word to describe the condition of the stream in relation to reference streams. Narratives are either Excellent (>4.5), Good (3.3-4.5), Fair (2.2-3.2), or Poor (<2.2).

 

 

 

 

 

 

 

 

 

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Herptofauna (Amphibians and Reptiles)

Stream Salamander Index of Biotic Integrity

Data from the first year (2008) of stream salamander sampling will be evaluated using the Stream Salamander Index of Biotic Integrity (SS-IBI) (Southerland et al. 2004; Southerland and Franks 2008). The current metrics for the SS-IBI in the Piedmont Region are:

  • Species richness and composition (Number of species)

  • Abundance (Number of salamanders)

  • Species tolerance (Number of intolerant salamanders)

  • Reproductive function (Number of adult salamanders)

This evaluation will determine if a modification to the IBI scoring methodology is needed. The IBI is being evaluated by the Maryland Biological Stream Survey.

 

Data and Species List

View a list of species found in Montgomery County  (PDF, 52KB)

Available Data: Montgomery County has amphibian and reptile data from its pilot program (2001-2007). Data from 2008 is expected to be available in the future.

Data Description: Herptofauna Pilot Program (2001-2007) Data Table
Field Description
Station The station field is a nine character code that identifies the monitoring station name. The stations are a combination of the two letter code for the watershed + the two letter code for the subwatershed + the single digit stream order code (1-4) + the sequential reach number (01-99).
SampleDate The date that the station was sampled.
Cname The common name of the species found followed by the life stage found (A=adult, L=larval, E=Egg). Example: American Bullfrog_A.
Scientific_Name The scientific name of the species found.
RBCount The number of individuals found during the right bank effort search.
LBCount The number of individuals found during the left bank effort search.
StrChCount The number of individuals found during the stream channel effort search.
A_StrCh The number of individuals found in the stream channel anecdotally from collection in the D-net in the spring, or during summer electrofishing.
A_InStr The number of individuals found in the stream anecdotally.
A_RipZone The number of individuals found in the riparian zone anecdotally.

 

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Stream Habitat 

Montgomery County has collected habitat data from 1994 to the present. Most monitoring stations have Rapid Habitat Assessment data for both the spring benthic and summer fish collections.

 

Stream Habitat Data Table
Field Name Description
STATION Two letter stream code + two letter stream reach code + order (1-4) + reach number (01-99).
SAMPLE_DATE The date that the station was sampled.
MON_TYPE A three character code that designates whether the habitat information was collected during a fish sample (BIF) or a benthic sample (BIB).
INSTR_COVER In-stream cover graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
EPI_SUBSTR Epifaunal substrate graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
EMBEDD Embeddedness of gravel, cobble, and boulders by sediment load graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
CH_ALTER Channel alteration (channelization or dredging) graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
SED_DEPOSIT Sediment deposition outside of the water column graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
RIFFLE_FREQ Frequency of riffles in the 75 meter section of the stream being sampled. Graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
CHAN_FLOW Channel flow status. This measurement ranges from full at normal stream flow to very little water in the channel. Graded according to the scheme 16-20 = optimal; 11-15 = suboptimal; 6-10 = marginal; 0-5 = poor.
LB_BANKVEG Vegetative bank protection on the left bank when facing downstream. Graded according to the scheme 9 -10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
RB_BANKVEG Vegetative bank protection on the right bank when facing downstream. Graded according to the scheme 9 -10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
LB_BANKSTAB Bank stability on the left bank when facing downstream. Graded according to the scheme 9-10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
RB_BANKSTAB Bank stability on the right bank when facing downstream. Graded according to the scheme 9-10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
LB_BUFFER Width of the riparian zone on the left bank as distance to the nearest human activities (i.e. parking lots, roads, mowed lawns, etc.) Graded according to the scheme 9-10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
RB_BUFFER Width of the riparian zone on the right bank as distance to the nearest human activities (i.e. parking lots, roads, mowed lawns, etc.) Graded according to the scheme 9-10 = optimal; 6-8 = suboptimal; 3-5 = marginal; 0-2 = poor.
COMMENTS Short text field for any habitat comments not covered by the above attributes.

 

 

Stream Habitat Narrative Data Table
Field Name Description
Station The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+ the two letter code for the subwatershed + the single digit stream order code+ the sequential reach number.
Sample Type Designates whether the sample was for Benthics or Fish.
Sample Year The year in which the station was sampled.
Sample Date The date the station was sampled.
Score The final habitat summary score (0-200).
Narrative Descriptive word to describe the condition of the stream in relation to reference streams. Narratives are either Excellent (166-200), Excellent/Good (154-165), Good (113-153), Good/Fair (101-112), Fair (60-100), Fair/Poor (48-59) or Poor (0-47).

 

Habitat scores are scored by a team of at least two biologists, and are somewhat subjective. Ideally, the scores from spring to summer should be somewhat similar.

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Physical and Chemical Data

Montgomery County has tabular physical chemistry data from 1994-present for most monitoring sites. 

Physical Chemical Data
Field Name Description
STATION The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+the two letter code for the subwatershed+ the single digit stream order code+ the sequential reach number.
SAMPLE_DATE The date the station was sampled.
MON_TYPE 3 character code associated with the type of monitoring done at the station.
DISOXY Dissolved oxygen in mg/L (from hydrolab).
[%_SAT] The % saturation as a function of dissolved oxygen and water temperature. 
PH The pH of the stream water.
CONDUCT The electric conductivity of the water at the sample station.
AIRTEMP The temperature of the air at the beginning of the sample (in degrees Celsius). 
H2OTEMP_C The temperature of the water at the beginning of the sample (in degrees Celsius). 
COMMENTS Additional comments that field staff may feel are appropriate.

 

Data Constraints

Instantaneous physical chemistry data is not a reflection of the long-term water quality of a stream. There may also be instances when the sampling equipment was malfunctioning or not calibrated correctly. Be careful to check comments. Also, most of the individual parameters should not be compared to each other due to differences in the time of year and even time of day samples were taken.

 

Stream Channel Survey Data

DEP stream channel survey data is entered into data forms, which log information on the following worksheets:

  • Introduction: information about the spreadsheet.

  • Summary: information about the study reach (name, date, location, drainage area, etc.)

  • Profile: longitudinal slope profile.

  • Pattern: calculation of sinuosity.

  • Materials:channel bed materials (pebble count information).

  • Dimension: cross-sections.

To access this data, contact DEP directly.

 

Stream Temperature Data

Montgomery County has collected instream temperature data from 1995 to the present. However, the sites selected for temperature monitoring would not be available for every year since 1995. Tables and maps are available showing the locations where temperature was monitored during specific years. Maps can be made to order depending on the request.

Temperature Data Table
Field Name Description
Station The station field is a nine character code that identifies the station name. The stations are a combination of the two letter code for the watershed+the two letter code for the subwatershed + the single digit stream order code+ the sequential reach number.
Date The date and time the water temperature was recorded.
Temperature Water temperature in Celsius.

 

Data Constraints

For proper interpretation, water temperature data should be compared with air temperature and precipitation data from the same time period.

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