(a) Public Water Supply. The following criteria are for evaluation of stream quality at the point at which water is withdrawn for treatment and distribution as a potable supply:
(1) Bacteria. Coliform group not to exceed 5,000 per 100 ml as a monthly average value (either MPN or MF count); nor exceed this number in more than twenty percent (20%) of the samples examined during any month; nor exceed 20,000 per 100 ml in more than five percent (5%) of such samples.
(2) Threshold-odor number. Not to exceed twenty-four (at 60 degrees C.) as a daily average.
(3) Dissolved solids. Not to exceed 500 mg/1 as a monthly average value, nor exceed 750 mg/1 at any time.
(4) Radioactivity. Gross beta activity not to exceed 1,000 picocuries per liter (pCi/l), nor shall activity from dissolved strontium-90 exceed 10 pCi/l, nor shall activity from dissolved alpha emitters exceed 3 pCi/l.
(5) Chemical constituents. Not to exceed the following specified concentrations at any time:
Constituent | Concentration (mg/l) |
Arsenic |
0.05 |
Barium |
1.0 |
Cadmium |
0.01 |
Chromium (hexavalent) |
0.05 |
Cyanide |
0.025 |
Fluoride |
1.0 |
Lead |
0.05 |
Selenium |
0.01 |
Silver |
0.01 |
(b) Industrial Water Supply. The following criteria are applicable to stream water at the point at which the water is withdrawn for use (either with or without treatment) for industrial cooling and processing:
(1) Dissolved oxygen. Not less than 2.0 mg/1 as a daily-average value, nor less than 1.0 mg/1 at any time.
(2) pH. Not less than 5.0 nor greater than 9.0 at any time.
(3) Temperature. Not to exceed ninety-five degrees Fahrenheit (95o F) at any time.
(4) Dissolved solids. Not to exceed 750 mg/1 as a monthly average value, nor exceed 1,000 mg/1 at any time.
(c) Aquatic Life A. The following criteria are for evaluation of conditions for the maintenance of a well-balanced, warm-water fish population. They are applicable at any point in the stream except for areas necessary for the admixture of waste effluents with stream water:
(1) Dissolved oxygen. Not less than an average of 5.0 mg/1 per calendar day and not less than 4.0 mg/1 at any time.
(2) pH.
A. No value below 6.0 nor above 8.5.
B. Daily fluctuations which exceed the range of pH 6.0 to pH 8.5 and are correlated with photosynthetic activity may be tolerated.
(3) Temperature.
A. No abnormal temperature changes that may affect aquatic life unless caused by natural conditions.
B. The normal daily and seasonal temperature fluctuations that existed before the addition of heat due to other than natural causes shall be maintained.
C. Maximum temperature rise at any time or place above natural temperatures shall not exceed five degrees Fahrenheit (5o F). In addition, the water temperature shall not exceed the maximum limits indicated in the following table.
Maximum Temperature in Degrees Fahrenheit During Month
WATERS | Jan. | Feb. | Mar. | Apr. | May | June | July | Aug. | Sept. | Oct. | Nov. | Dec. |
All waters except Ohio River | 50 | 50 | 60 | 70 | 80 | 90 | 90 | 90 | 90 | 78 | 70 | 57 |
(4) Toxic Substances. Not to exceed one-tenth of the forty-eight hour median tolerance limit, except that other limiting concentrations may be used in specific cases when justified on the basis of available evidence and approved by the appropriate regulatory agency.
(d) Aquatic Life B. The following criteria are for evaluation of conditions for the maintenance of desirable biological growths and, in limited stretches of a stream for permitting the passage of fish through the water, except for areas necessary for admixtures of effluents with stream water:
(1) Dissolved oxygen. Not less than 3.0 mg/1 as a daily-average value, nor less than 2.0 mg/1 at any time.
(2) pH. Not less than 6.0 nor greater than 8.5 at any time.
(3) Temperature. Not to exceed ninety-five degrees Fahrenheit (95o F.) at any time.
(4) Toxic substances. Not to exceed one-tenth of the forty-eight hour median tolerance limit, except that other limiting concentrations may be used in specific cases when justified on the basis of available evidence and approved by the appropriate regulatory agency.
(e) Recreation. The following criterion is for evaluation of conditions at any point in waters designated to be used for recreational purposes, including but not limited to water-contact activities as swimming and water skiing:
(1) Free from substances attributable to municipal, industrial, agricultural, or other discharges that will settle to form putrescent or otherwise objectionable sludge deposits.
(2) Free from floating debris, oil, scum and other floating materials attributable to municipal, industrial, agricultural or other discharges in amount sufficient to be unsightly or deleterious.
(3) Free from substances attributable to municipal, industrial, agricultural or other discharges in concentrations or combinations which are toxic or harmful to human, animal, plant or aquatic life.
(Ord. 19-91. Passed 3-18-91.)