Laserfiche WebLink
2.04.7 Hydrology Description <br />significant flows and cause significant dewatering of the river. Some of this <br />water returns to the river near and below Paonia. <br />Irrigation has significant effects on water volume and quality of the North <br />Fork. It contributes to reduced flows and increased salinity, nutrients, and <br />probably herb icidelpesticide levels. Indirectly, lower flows contribute to <br />higher summer temperatures. The municipality of Hotchkiss (below Paonia), <br />and several smaller communities along the valley and mesas are also <br />sources of nutrients as the result of effluents from discharges directly into the <br />river and through the groundwater. There is little industrial use or discharge <br />of water to the North Fork, particularly in the upper part of the valley, <br />although several coal mines have operated in the past and are presently <br />operating. <br />The North Fork of the Gunnison River, into which streams draining the <br />Somerset Coal Field flow, is severely affected by human activities, primarily <br />agriculture. Coal mines in the area currently discharge fairly significant flows <br />into the river. The West Elk Mine, Elk Creek Mine and Bowie No. 2 Mine all <br />have discharged or are discharging mine water to the river. Near Somerset, <br />the water is a calcium - bicarbonate type, typical of runoff from mountain <br />areas, and contains total dissolved - solids concentrations of less than 200 <br />mgll (ref. Bear 2009 AHR). The Applicant monitors the North Fork above <br />and below the mine site. The minimum, average and maximum TDS values <br />recorded in the North Fork of the Gunnison River below the Bowie No. 2 <br />mine site are 50,159 and 692 mg /l respectively. (ref. Bowie No. 2 Mine 2012 <br />AH R) <br />Streams Draining Permit and Adjacent Areas <br />Three tributary watersheds have been identified within or adjacent to the <br />Permit Area: Stevens Gulch, Terror Creek and Hubbard Creek. Large <br />discharges typically occur in March through July, with peak flows occurring in <br />late April or early May. <br />The Hubbard Creek and Terror Creek drainages are characterized by steep <br />to nearly vertical canyon walls. As both creeks are perennial and tributary to <br />the North Fork, the aquatic life in the creeks is similar to that of the North <br />Fork. Riparian vegetation occurs along the immediate streambanks, <br />PR -14 2.04-47- 03114 <br />