Ohio Surface Water Quality Data

Water Chemistry Summary Statistics

The following table presents summary statistics for water quality parameters collected from streams and rivers in the State of Ohio.  The "Count" column contains the number of results in the dataset for each parameter.  The "Non Detect" column contains the percentage of samples for which the results are below the minumum detection limit of the analysis.  The "MDL" column contains the minimum detection limit of the analysis.  The columns with a percent as the heading contain the percentile values of each parameter for the dataset.

ParameterCountNon DetectMDL10%25%50%75%90%95%
Acidity (mg/l)12,68498%5.05.005.005.005.005.005.00
Alkalinity (mg/l)18,9851%20074.90116.00168.00225.00269.00288.00
Aluminum (ug/l)24,56348%2.0200.00200.00212.00579.001700.003860.00
Ammonia (mg/l)27,35449%0.050.050.050.050.100.230.43
Arsenic (ug/l)24,08052%2.02.002.002.002.904.005.20
Barium (ug/l)24,1170%2.036.0048.0062.0081.00103.00118.00
BOD5 (mg/l)20,95275%2.02.002.002.002.003.705.30
Cadmium (ug/l)20,95275%0.200.200.200.200.200.370.53
Calcium (mg/l)24,1470%2.038.0053.0070.0085.00101.00116.00
Carbonate (mg/l)5496%5.05.005.005.005.005.005.00
CBOD20 (mg/l)3,4973%3.03.304.105.306.708.4010.00
CBOD5 (mg/l)1,93686%2.02.002.002.002.002.303.50
Chloride (mg/l)26,6571%1.014.6024.0039.9068.60123.00166.00
Chlorophyll_a (ug/l)1520%0.11.132.556.8026.8359.4885.00
Chromium (ug/l)24,10792%3030.0030.0030.0030.0030.0030.00
COD (mg/l)23,17738%1010.0010.0013.0020.0028.0036.00
Conductivity (umhos/cm)22,3730%2.0349.00488.00643.00798.001020.001240.00
Copper (ug/l)22,08396%1010.0010.0010.0010.0010.0010.00
Copper, Low Level (ug/l)2,28944%2.02.002.002.203.605.106.50
Cyanide, Free (mg/l)244100%5.05.005.005.005.005.005.00
Cyanide, Total (ug/l)16392%10.010.0010.0010.0010.0010.0012.05
DCBOD20 (mg/l)711%3.03.303.604.405.406.908.15
DOC (mg/l)620%2.03.113.404.205.205.806.79
E.coli (#/100ml)9,49953%1020.0070.00200.00590.002100.004400.00
Fecal Coliform (#/100ml)9,35749%1050.00140.00370.001000.003800.008298.40
Fecal Strep. (#/100ml)1,48128%10100.00260.00650.002300.009000.0021000.00
Fluoride (mg/)3910%0.20.200.260.821.2217.2824.12
Hardness, Total (mg/l)24,1240%10141.00202.00273.00338.00395.00453.00
Hexavalent Chromium (ug/l)4464%1010.0010.0010.0011.5015.7016.00
Iron (ug/l)23,8122%50145.00277.00535.001060.002250.003754.50
Lead (ug/l)24,06388%2.02.002.002.002.002.203.60
Magnesium (mg/l)24,1470%1.011.0016.0023.0031.0038.0044.00
Manganese (ug/l)23,9393%1019.0036.0076.00174.00394.00752.00
Mercury (ug/l)18,054100%0.20.200.200.200.200.200.20
Nickel (ug/l)22,11599%4040.0040.0040.0040.0040.0040.00
Nitrate+nitrite (mg/l)26,44212%0.10.100.281.123.005.748.00
Nitrite (mg/l)26,32358%0.020.020.020.020.030.070.11
Oil & Grease (mg/l)21963%2.02.002.002.002.302.973.41
Orthophosphate (mg/l)81012%0.010.010.020.060.170.450.95
pH (su)1,120N/AN/A7.787.958.108.238.388.49
Phenolics (ug/l)13788%1010.0010.0010.0010.0010.3013.44
Pheophytin_a (ug/l)1520%0.11.112.384.708.9016.0522.14
Potassium (mg/l)24,1211%2.02.003.004.005.007.0010.00
Selenium (ug/l)24,06699%2.02.002.002.002.002.002.00
Sodium (mg/l)24,0851%5.08.0013.0024.0044.0082.00112.00
Strontium (ug/l)24,1020%30118.00200.00375.50993.752840.004650.00
Sulfate (mg/l)21,8640%5.027.7041.1064.60107.00192.00311.00
TKN (mg/l)26,87811%0.20.200.330.550.821.171.48
TOC (mg/l)1,96915%2.02.002.504.007.409.1010.00
Total Dissolved Solids (mg/l)26,4030%10224.00306.00402.00504.00658.00816.00
TP, dissolved (mg/l)4940%2.00.010.020.070.150.270.55
TP, Low Level (ug/l)3411%1022.7030.6044.3061.1099.20128.00
Total Phosphorus (mg/l)26,62814%0.010.020.050.080.180.370.64
Total Solids (mg/l)710%5.0222.00303.00400.00658.00982.001245.00
Total Suspended Solids (mg/l)26,90729%5.05.005.009.0021.0047.0079.00
Total Volatile Solids (mg/l)400%5.067.8078.00102.00123.50223.60276.40
Turbidity (ntu)1663%1.02.284.019.0017.1537.6067.00
Volatile Suspended. Solids (mg/l)6641%5.05.005.005.007.008.5010.00
Zinc (ug/l)23,90362%1010.0010.0010.0014.0027.0045.00

Result Qualifier Table

The following table presents the qualifier codes and definitions that may be applicable to individual sample results.  Qualifier codes indicate that a result is limited or modified in some way. Use caution when including qualified results in your analysis.

QualifierDefinition
BAnalytical result is estimated. Analyte was detected in the associated method/trip/field blank as well as in the sample.
EAnalyte was quantitated but the concentration exceeds the instrument's calibration range for that specific analysis. Sample could not be re-analzyed within the holding time.
JThe analyte was positively identified, the associated numerical value is estimated.
UJThe analyte was not detected above the sample quantitation limit (QL). However, the reported QL is estimated.
JLThe reported result is estimated because it has been computed using a colony count that is not within the acceptable counting range. (Microbiological analysis only)
PQBoth analyte results are acceptable because they are withing the precision quality control limits for each analyte. This is only applicable to co-analytes, such as (cBOD-5 vs BOD-5; BOD-5 cs COD; NH3 vs TKN; Solids-Diss. vs Conductivity; Solids-Diss. vs Hardness; Nitrate-Nitrite vs Nitrite).
PTReported result is estimated because the sample was not analyzed within the required holding time.
PSThe reported result is estimated because the sample was not submitted to the laboratory within the required shipping time. This prevented sample analysis within the required holding time.
RThe analyte result is unusable because quality control criteria was not met.
RCThe result is rejected because of poor correlation with its co-analyte, such as (cBOD-5 vs BOD-5; BOD-5 cs COD; NH3 vs TKN; Solid-Diss. vs Conductivity; Solids-Diss. vs Hardness; Nitrate-Nitrite vs Nitrite).
Map Instructions:

This page provides access to water chemistry and stream sediment data collected by the Ohio EPA.  Zoom the map to your area of interest and nearby monitoring locations will draw.  Click on an individual location to view its description and associated sampling results.

Summary Statistics:

Individual sample results may be compared to summary statistics of the database to illustrate their relative significance.  Summary statistics for commonly-sampled water-chemistry parameters may be viewed by selecting "Statistics Table" from the above drop-down list.

Qualified Results:

An individual result may be qualified, indicating the result is limited or modified in some way.  If a result is qualified, it is noted by a code in parenthesis.  To view a table of the code definitions, select "Qualifier Table" from the above drop-down list.