Rock Creek, Cedar Draw, Deep Creek And Big Wood River - Canal System

01. Rock Creek, Cedar Draw, and Deep Creek. For the purposes of water quality protection, the following waterways are recognized as used by the Twin Falls Canal Company as spillways, collection and IDAHO ADMINISTRATIVE CODE IDAPA 58.01.02 Department of Environmental Quality Water Quality Standards Section 283 Page 171 conveyance facilities and such waterways shall also be protected for those uses: Rock Creek from the intersection with the High Line Canal of the Twin Falls Canal System to the mouth; Cedar Draw from the intersection with the High Line Canal of the Twin Falls Canal System to the mouth, Deep Creek from the intersection with the High Line Canal of the Twin Falls Canal system to the mouth, all in Twin Falls County. (3-31-22) 02 Big Wood River -- Canal System. For the purposes of water quality protection, the following waterway is also recognized as used by the North Side Canal Company for the purposes of conveying canal water and shall also be protected for that use: Big Wood River from the point of union with the North Side Canal System, located in Section 31, T. 5 S., R. 15 E., Boise Meridian, downstream to the last irrigation diversion of the North Side Canal Company from the Malad River located in Section 25, T. 6 S., R. 13 E., Boise Meridian. (3-31-22) 281. -- 282. (RESERVED) 283. SPOKANE RIVER, SUBSECTION 110.12, HUC 17010305, UNITS P-3 AND P-4, SITE-SPECIFIC CRITERIA FOR AMMONIA. The following criteria are to be met dependent upon the temperature, T (degrees C), and pH of the water body: (3-31-22) 01. Acute Criterion (Criterion Maximum Concentration (CMC)). The one (1) hour average concentration of total ammonia nitrogen (in mg N/L) is not to exceed, more than once every three (3) years, the value calculated using the following equation: (3-31-22) 02. Chronic Criterion (Criterion Continuous Concentration (CCC)). (3-31-22) a. The thirty (30) day average concentration of total ammonia nitrogen (in mg N/L) is not to exceed, more than once every three (3) years, the value calculated using the following equation: (3-31-22) b. The highest four (4) day average within the thirty (30) day period should not exceed two and five tenths (2.5) times the CCC. (3-31-22) 284. SOUTH FORK COEUR D'ALENE SUBBASIN, SUBSECTION 110.09, HUC 17010302, AQUATIC LIFE CRITERIA FOR CADMIUM, LEAD AND ZINC. The following criteria are to be met dependent upon the hardness, expressed as mg/l of calcium carbonate, of the water. Criterion maximum concentrations (CMC), one (1) hour average concentrations, and criterion continuous concentrations (CCC), four (4) day average concentrations, of the dissolved metals (in µg/l) are not to exceed, more than once every three (3) years, the values calculated using the following equations: (3-31-22) 01. Cadmium. (3-31-22) a. CMC = 0.973 x e [(1.0166 x ln(hardness)) – 3.924] (3-31-22) b. CCC = [1.101672 – (ln (hardness) x 0.041838] x e [(0.7852 x ln(hardness)) – 3.490] (3-31-22) 02. Lead. (3-31-22) a. CMC = e [(0.9402 x ln(hardness)) + 1.1834] (3-31-22) b. CCC = e [(0.9402 x ln(hardness)) - 0.9875] (3-31-22) 204 . 7 204 . 7 10 1 0 . 39 10 1 275 . 0       pH pH CMC ) 10 45 .1, 85 .2 ( 10 1 487 .2 10 1 0577 .0 ) 25 ( 028 .0 688 .7 688 .7 T pH pH MIN CCC                 IDAHO ADMINISTRATIVE CODE IDAPA 58.01.02 Department of Environmental Quality Water Quality Standards Section 285 Page 172 03. Zinc. (3-31-22) a. CMC = e [(0.6624 x ln(hardness)) + 2.2235] (3-31-22) b. CCC = e [(0.6624 x ln(hardness)) + 2.2235] (3-31-22) 04. Application. (3-31-22) a. The maximum hardness allowed for use in the equations in Section 284 shall not be greater than four hundred (400) mg/l even if the actual ambient hardness is greater than four hundred (400) mg/l. (3-31-22) b. The criteria described in Section 284 apply to all surface waters within the subbasin, except for natural lakes, for which the statewide criteria given in Section 210 apply. (3-31-22) 285. SNAKE RIVER, SUBSECTION 140.13, HUC 17050115, UNIT SW1; AND SUBSECTION 140.19, HUC 17050201, UNITS SW1, SW2, SW3 AND SW4, SITE-SPECIFIC CRITERIA FOR WATER-COLUMN DISSOLVED OXYGEN. A minimum of six and five-tenths (6.5) mg/l of water-column dissolved oxygen shall be met in the Snake River from the Idaho/Oregon border to Hell’s Canyon Dam. (3-31-22) 286. SNAKE RIVER, SUBSECTION 130.01, HUC 17060101, UNIT S1, S2, AND S3; SITE-SPECIFIC CRITERIA FOR WATER TEMPERATURE. Weekly maximum temperatures (WMT) are regulated to protect fall chinook spawning and incubation in the Snake River from Hell’s Canyon Dam to the confluence with the Salmon River from October 23 through April 15. Because the WMT is a lagged seven (7) day average, the first WMT is not applicable until the seventh day of this time period, or October 29. A WMT is calculated for each day after October 29 based upon the daily maximum temperature for that day and the prior six (6) days. From October 29 through November 6, the WMT must not exceed fourteen point five degrees C (14.5°C). From November 7 through April 15, the WMT must not exceed thirteen degrees C (13°C). (3-31-22)