(1967–1968) Segment Completion Report: Region I-B Fisheries Studies, Job No. 2, Pollution Studies

--- Page 3 --- SEGMENT COMPLETION REPORT STATE OF Texas PROJECT NO, Fe5-R-15 _ NAME ___ Region I-B Fisheries Studies JOB NO, 2 TITLE__ Pollution Studies PERIOD COVERED March 1, 1967 to February 29, 1968 Objectives: To determine the source and nature of pollution. Ls To determine extent of damage to fish populations. es To trace the source of pollution. 3 To attempt to determine the nature of the pollutant, A. To report instances of violation and negligence to the State Water Pollution Control Board. Procedures: Field investigations were made where pollution was encountered or reported. The findings from these efforts were reported to appropriate authorities if remedial measures were possible or needed. Findings; A fish kill was reported on the Colorado River just below the farm road 2059 crossing (Coke County) in May 1967. Field investigations began the following day. Due to the low rainfall, the river was not running as normal and had receded to long shallow holes. Dead and dying fish were found over a 2-mile distance of the river.’ These fish were mainly gizzard shad, river carpsucker, channel catfish, various sunfish and a large number of minnows. Fish sampling with gill nets, seines and rotenone showed complete fish kills in some holes and large reductions in the fish populations in most of the other areas. Water analysis revealed chlorides to be as high as 7,700 ppm, and dissolved oxygen varied between 1.0 and 3.0 ppm. Either of the above conditions could be lethal to fish over a short period of time. Most of this salt pollution is from natural sources and concentrated by dry weather. However, oil fields on the upper watershed are probably contributing to the high chloride content. These more or less natural fish die-offs continued to occur on the Colorado River from Robert Lee (Coke County) almost to Colorado City (Mitchell County) until midsummer rains were sufficient to resume the flow. Periodic --- Page 4 --- checks made on the river during this time found water conditions and fish kills similar to that discussed earlier. The total number of fish killed could not be determined because of the extended period of time covered and the 40-mile distance of the river concerned. However, it is estimated that several thousand each of gizzard shad, river carpsucker and small channel catfish died. Other fish lost included an enormous number of minnows, several hundred sunfish, and a few longnose gar and flathead catfish. ' These findings did not warrant reporting to the State Water Quality Board because they resulted from natural causes. Recommendations; It is recommended that this job be continued to cope with future pollution problems. Lie ee Prepared by Billy J. Follis Approved by soft, Project Leader Coordinator Date February 21, 1968 Leo D. Lewis Inland Fisheries Supervisor