| Buckhorn Geotech Engineering Report |
Mancos Water Conservancy District
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| Chances of ZEBRA MUSSELS colonization in Jackson Gulch Reservoir are very low. Coal outcrops contribute CO2 to the lake, and CO2 concentrations are fatal for Dreissena. Given the adaptive nature of the quagga mussels, the growth and expansion of Dreissena needs to be monitored for many years before any lake or water body can be declared invulnerable to colonization. Environmental conditions that they can tolerate should be studied further. The potential is low for establishment of Dreissena at Jackson Gulch Reservoir. The geology of the reservoir basin includes coal seams in the Dakota Formation. Coal contributes dissolved CO2 to the water, and high CO2 concentrations are fatal for Dreissena and interfere with development of their shells. Compared with lakes across the U.S. with zebra and quagga mussels, Jackson Gulch has much different water quality with lower CalSat Potential, low pH values, and high CO2 concentrations. The conditions are Jackson Gulch, therefore, are unsuitable for zebra and quagga mussel colonization. However, given the ability of these mussels to adapt to their environment, the growth and expansion of Dreissena needs to be monitored, and water-quality conditions where they survive must be documented. More research needs to be done on the potential for Dreissena to be transported downstream from lakes to rivers and canals. |