APPENDIX 4 Hot Springs Draft Flow Monitoring
106 Ridgeway, Suite C • Hot Springs, AR 71901 • 501.366.6060 • www.rjn.com www.rjn.com October 20, 2015 Mr. Larry Merriman Utilities Project Manager City of Hot Springs 111 Opera St. Hot Springs, AR 71901 Subject: City of Hot Springs, Arkansas Post-Rehabilitation Flow Monitoring Conducted in 2015 Dear Mr. Merriman: According to the March 31, 2013 Engineering Agreement, RJN is pleased to present this final report for the above referenced project. This final report includes the analysis and results from post rehabilitation flow monitoring in basins comprising the tributary area of the Davidson Wastewater Treatment Plant. We appreciate the opportunity to work with the City of Hot Springs and the excellent cooperation from the City’s staff throughout the project. Should you have any questions, please call. Very truly yours, RJN GROUP, INC. Daniel Jackson, P.E. Project Manager Tristan Nickel, P.E. Project manager DJ/18-2841-00 Enclosure
2015 POST-REHABILITATION FLOW MONITORING FINAL REPORT CITY OF HOT SPRINGS, ARKANSAS FEBRUARY 2010 I hereby certify that this report was prepared under my direct supervision and that I am a duly registered Professional Engineer under the laws of the State of Arkansas. Date: 10/20/15 Registration No.: 13978
RJN Group, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Post Rehabilitation Flow Monitoring Background .................................................................................................................. 1 Description of Existing Conditions ............................................................................ 11 Definitions and Abbreviations .................................................................................... 11 Methodology .............................................................................................................. 12 Determination of Average Daily Dry-Weather Flow .......................................... 12 Average Daily Dry-Weather Flow Peaking Factor .............................................. 13 Infiltration Conditions .......................................................................................... 13 Determination of Peak Infiltration ....................................................................... 13 Inflow Conditions ................................................................................................ 14 Determination of Inflow ...................................................................................... 14 Post-Rehabilitation Study ........................................................................................... 14 Dry-Weather Flow Comparison ........................................................................... 20 Wet-Weather Flow Comparison .......................................................................... 20 Infiltration Analysis ................................................................................ 23 Inflow Analysis ....................................................................................... 23 Summary of Findings ................................................................................................. 23 Figures Figure 1 Flow Meter Locations, Rain Gauge Locations, and Basin Boundaries .... 9 Figure 2 Basin Flow Diagram ............................................................................... 10 List of Tables 1 Flow Monitoring Locations ...................................................................... 2 2 Rainfall Summary ..................................................................................... 3 3 Dry-Weather Comparison for Rehabilitated Basins ............................... 21 4 Infiltration Data....................................................................................... 25 5 Inflow Data ............................................................................................. 27 TABLE OF CONTENTS