Silver Creek - Division of Water Quality - Utah.gov

Silver Creek Watershed TMDL Final Report
Table of Contents
Silver Creek TMDL Executive Summary .................................................................................. 3
1.0 INTRODUCTION ............................................................................................................ 7
1.1 Watershed Description.................................................................................................... 7
1.2 Water Budget .................................................................................................................. 9
1.3 Water Quality Impairment ............................................................................................ 12
1.4 Effects of Zinc and Cadmium....................................................................................... 12
2.0 WATER QUALITY STANDARDS .............................................................................. 14
2.1 Water Quality Targets and Endpoints........................................................................... 14
3.0 WATER QUALITY DATA ........................................................................................... 17
3.1 Sources of Data............................................................................................................. 17
3.2 Data Limitations............................................................................................................ 17
3.3 Key Sampling Locations............................................................................................... 18
4.0 DATA ANALYSIS RESULTS....................................................................................... 20
4.1 Zinc and Cadmium Standards....................................................................................... 20
4.2 Water Quality and Flow Results by Location............................................................... 20
4.4 Zinc and Cadmium Loading ......................................................................................... 29
4.4 Water Quality Overview............................................................................................... 32
4.5 Zinc and Cadmium Geochemistry Overview ............................................................... 33
5.0 MARGIN OF SAFETY.................................................................................................. 34
5.1 Assumptions.................................................................................................................. 34
5.2 Margin of Safety ........................................................................................................... 34
6.0 SOURCES........................................................................................................................ 35
6.1 Known Sources of Contaminants.................................................................................. 35
6.2 Future sources ............................................................................................................... 39
7.0 TECHNICAL ANALYSIS............................................................................................. 41
7.1 Estimation of Existing Load ......................................................................................... 41
7.2 Comparison of Existing Load and Loading Capacity................................................... 41
8.0 TMDL .............................................................................................................................. 43
8.1 Zinc ............................................................................................................................... 44
8.2 Cadmium....................................................................................................................... 44
8.3 Silver Creek Water Reclamation Facility ..................................................................... 44
9.0 BEST MANAGEMENT PRACTICES......................................................................... 47
9.1 Source Control BMPs ................................................................................................... 47
9.2 Treatment Control BMPs.............................................................................................. 48
10.0 PROJECT IMPLEMENTATION PLAN..................................................................... 49
10.1 Implementation Measures............................................................................................. 49
10.2 Implementation Measures by Site................................................................................. 52
10.3 Implementation Measures Efficiencies and Costs ........................................................ 56
10.4 Implementation Schedule.............................................................................................. 60
11.0 TMDL EVALUATION AND MONITORING PLAN ................................................ 61
12.0 PUBLIC PARTICIPATION.......................................................................................... 62
12.1 Public Participation Meetings....................................................................................... 62
12.2 Subcommittees and Groups .......................................................................................... 62
Page 1