Santa Fe River and Arroyo de Los Chamisos Modeling Report Santa Fe River and Arroyo de Los Chamisos Modeling Report #100-IWM-T37272 July 26, 2018 PRESENTED TO PRESENTED BY City of Santa Fe Tetra Tech P +1-505-982-0584 200 Lincoln Avenue 502 W. Cordova Rd. tetratech.com Santa Fe, New Mexico Suite C 87504-0909 Santa Fe, NM 87505 Prepared by: Sam Sarkar 07/26/2018 Civil Engineer Vahid Zarezadeh, PhD Environmental Engineer Reviewed by: Troy Dorman, PhD, PE 07/26/2018 Director Restriction on Disclosure and Use of Data This proposal includes data that shall not be disclosed outside the Government and shall not be duplicated, used, or disclosed—in whole or in part—for any purpose other than to evaluate this proposal. If, however, a contract is awarded to this offeror as a result of—or in connection with—the submission of this data, the Government shall have the right to duplicate, use, or disclose the data to the extent provided in the resulting contract. This restriction does not limit the Government’s right to use information contained in this data if it is obtained from another source without restriction. The data subject to this restriction are constrained on each sheet of this submittal. i City of Santa Fe, New Mexico Santa Fe River and Arroyo de Los Chamisos Modeling Report TABLE OF CONTENTS 1.0 INTRODUCTION ..................................................................................................................................................3 2.0 DATA PREPARATION ........................................................................................................................................3 2.1 Watershed Delineation and Stream Definition ...............................................................................................3 2.2 Subcatchment Naming Convention ...............................................................................................................5 2.3 Land Use, Soil, and Curve Number Map .......................................................................................................6 2.4 Stormwater Conveyance System ................................................................................................................ 13 3.0 HYDROLOGIC AND HYDRAULIC MODELING ............................................................................................... 15 3.1 Precipitation data ........................................................................................................................................ 15 3.2 Rainfall-runoff generation ............................................................................................................................ 15 3.3 XPSWMM model ......................................................................................................................................... 16 4.0 WATER QUALITY MODELING ........................................................................................................................ 18 4.1 LSPC Model Development .......................................................................................................................... 18 5.0 RESULTS AND DISCUSSION .......................................................................................................................... 19 5.1 XPSWMM MODEL ...................................................................................................................................... 19 5.1.1 Model Calibration ............................................................................................................................... 19 5.1.2 Slope Analysis ................................................................................................................................... 20 5.1.3 Velocity Analysis ................................................................................................................................ 22 5.1.4 Peak Flow Analysis ........................................................................................................................... 24 5.1.5 Culvert Capacity Analysis .................................................................................................................. 26 5.2 LSPC MODEL ............................................................................................................................................. 29 5.2.1 Hydrology Simulation ......................................................................................................................... 29 5.2.2 Water Quality Simulation ................................................................................................................... 33 6.0 PRIORITY AREAS FOR GREEN INFRASTRUCTURE IMPLEMENTATION .................................................. 37 7.0 FUTURE MODEL ENHANCEMENTS............................................................................................................... 39 8.0 STORMWATER PROGRAM RECOMMENDATIONS ...................................................................................... 39 9.0 BIBLIOGRAPHY ............................................................................................................................................... 41 LIST OF TABLES Table 1. Source of the naming for tributaries. ............................................................................................................5 Table 2. Runoff curve numbers for urban areas (USDA, 1986). ................................................................................7 Table 3. Land use classification of parcels data. ........................................................................................................8 Table 4. land use coding based on the classes. ........................................................................................................8 Table 5. Residential areas classification based on their size. ....................................................................................9 i City of Santa Fe, New Mexico Santa Fe River and Arroyo de Los Chamisos Modeling Report Table 6. Design storm values for Santa Fe area (inches) ....................................................................................... 15 Table 7. Typical values of Cp (iSWM, 2010). .......................................................................................................... 15 Table 8. Curve Number and Slope classification. ................................................................................................... 16 Table 9. Reservoirs in Headwaters Santa Fe River watershed. ............................................................................. 16 Table 10. 100-year flow comparison between FEMA and XPSWMM data. ............................................................ 19 Table 11. Designed conduit dimensions to convey 10-year storm event. ............................................................... 27 Table 12. Simulated average annual sediment, total nitrogen and total phosphorus loads for the Santa Fe River and Arroyo de Los Chamisos LSPC models. .......................................................................................................... 33 LIST OF FIGURES Figure 1. Headwaters Santa Fe River and Arroyo de Los Chamisos Watersheds, subcatchments, and stream networks. ....................................................................................................................................................................4 Figure 2. Soil map for headwaters Santa Fe River and Arroyo de Los Chamisos watersheds. ............................. 10 Figure 3. Land use map for headwaters Santa Fe River and Arroyo de Los Chamisos watersheds. .................... 11 Figure 4. Curve number map for headwaters Santa Fe River and Arroyo de Los Chamisos watersheds. ............ 12 Figure 5. Location of data points (surveyed and collected) for pipes and culverts. ................................................ 14 Figure 6. Stream networks selected for hydraulic modeling inside XPSWMM. ...................................................... 17 Figure 7. Average slope in reach segments. ........................................................................................................... 21 Figure 8. Maximum velocity in reach segments. ..................................................................................................... 23 Figure 9. Maximum flow per acre of each subcatchment. Flow Comparison locations are shown by star and listed in the above table. ................................................................................................................................................... 25 Figure 10. Location of surcharged pipes and culverts for 10-year and 100-year storm events and areas with reported flooding issues. ......................................................................................................................................... 28 Figure 11. Simulated water balance for the Arroyo de Los Chamisos and Santa Fe River LSPC models. ............ 30 Figure 12. Simulated streamflow duration for the Santa Fe River and Arroyo de Los Chamisos. .......................... 31 Figure 13. Ratio of LSPC simulated surface runoff to precipitation for the Santa Fe River and Arroyo de Los Chamisos watersheds. ............................................................................................................................................ 32 Figure 14. LSPC simulated annual average sediment load for the Santa Fe River and Arroyo de Los Chamisos watersheds.