9506 - Laserfiche WebLink

Home Browse Search

INTRODUCTION AND METHODS The purpose of this report is to evaluate the physical, chemical and biological characteristics of the Escalante Ranch wetlands. This project is focused at determining how the wetlands function at present, the history of these wetlands, and the possibilities of using these wetlands for razorback sucker habitat. The studies reported here are original, based upon field and laboratory analyses during June through September 1993. We conducted investigations of site characteristics that would allow us to determine if any problems existed which would make the site suitable, or unsuitable for the fish recovery program. We studied site history to understand the evolution of landforms, hydrology, and vegetation over tiune. We examined vertical aerial photographs obtained from the U.S. Soil Conservation Service for the years 1937, 1952, 1954, 1961, 1980 and 1987. A considerable amount of detail is visible on these photographs, particularly how much land is dry vs wet and distinctive vegetation patterns, such as the presence of cottonwood trees. For our hydrologic studies we established 4 staff gauges in water bodies on site and also installed 7 ground water monitoring wells. Wells were constructed of 1 inch PVC pipe. Holes were hand augured to reach the water table. Our goal was to establish wells which would allow us to determine the elevation of the water table through our sample period. Machine slotted PVC pipe was used in the lower portion of the well and unslotted PVC pipe in the upper part. The well was capped on the bottom and top ends and depth to water table was determined with a well-reader. Surface and ground water levels were recorded regularly during the sample period. Data on Green River stage was determined at a staff gauge established by the Bureau of Reclamation. River water levels are used to correlate with water levels in the wetlands. This allowed us to determine whether river and wetlands were hydrologically connected or whether the wetlands are fed largely by another water source. The wells and staff gauges also helped us to determine the duration of inundation in wetlands. Physical and chemical characteristics of water at staff gauges (surface waters) and wells (groundwater) stations were determined in the field and laboratory. We determined pH, conductivity, DO and temperature at sample times using a ICM water analyzer Model 51601.- For well samples, water was pumped using a hand pump until several well volumes had been removed and the water ran clear. Surface and groundwater samples were collected for chemical analysis from these same stations. For 1