Section 69-05.2-16-07 - Performance standards - Hydrologic balance - Stream channel diversions1. Flow from perennial and intermittent streams within the permit area may be diverted, if the diversions: a. Are approved by the commission after making the findings in section 69-05.2-16-20; b. Comply with other requirements of this chapter; c. Comply with local and state laws and regulations; and d. Are certified by a qualified registered professional engineer as being designed and constructed as required by this section. 2. When streamflow diversion is allowed, the diversion must be designed, constructed, and removed as follows: a. The longitudinal profile of the stream, the channel, and the floodplain must be designed and constructed to remain stable and to prevent, to the extent possible using the best technology currently available, additional contributions of suspended solids to streamflow or to runoff outside the permit area. These contributions may not exceed the limits established by state law. Erosion control structures such as channel lining structures, retention basins, and artificial channel roughness structures may be used in diversions only when approved by the commission. These structures may be approved for permanent diversions only where they are stable and will require infrequent maintenance. b. The combination of channel, bank, and floodplain configurations must be adequate to pass safely the peak runoff of a ten-yea, twenty-four-hour precipitation event for temporary diversions, a one-hundred-year, twenty-four-hour precipitation event for permanent diversions, or larger events specified by the commission. However, the capacity of the channel itself should be at least equal to the capacity of the unmodified stream channel immediately upstream and downstream of the diversion. 3. When no longer needed, all temporary stream channel diversions must be removed and the affected land reclaimed. At the time diversions are removed, downstream water treatment facilities previously protected by the diversion must be modified or removed to prevent overtopping or failure of the facilities. This requirement does not relieve the operator from maintaining a water treatment facility otherwise required under this chapter or the permit. 4. When permanent diversions are constructed or natural stream channels restored after being temporarily diverted, the operator shall: a. Restore, enhance where practicable, or maintain natural riparian vegetation on the banks of the stream. b. Establish or restore the stream to its natural meandering shape at an environmentally acceptable gradient, as approved by the commission. c. Establish or restore the stream to a longitudinal profile and cross section, including aquatic habitats (usually a pattern of riffles, pools, and drops rather than uniform depth) that approximate premining stream channel characteristics. N.D. Admin Code 69-05.2-16-07
Effective August 1, 1980; amended effective May 1, 1990; May 1, 1992.General Authority: NDCC 38-14.1-03
Law Implemented: NDCC 38-14.1-24, 38-14.1-42