December 7, Dr. Christine Pomeroy University of Utah Civil and Environmental Engineering MCE Salt Lake City, UT. Dear Dr.

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December 7, 2012 Dr. Christine Pomeroy University of Utah Civil and Environmental Engineering MCE 2042 Salt Lake City, UT 84112 Dear Dr. Pomeroy, The following document is the final report of the Red Butte Hydrologic Modeling Project as per your request. The report contains a summary of the work completed, a discussion of findings, and ideas for improving and expanding this modeling effort. Our team is pleased with the model we have produced. The extensive field data collection has paid off, and the model has proven quite accurate when compared to other studies and flooding accounts provided by both Salt Lake City and the County. We are excited to submit our work for review and several members of our team are even looking forward to continuing the improvement of this model in your class next semester. We hope that the following document adequately represents the amount of time and effort that each member of our team has put forth over the last 4 months. Regards, Austin Orr CME 119 Back wall Facing Window, Green Chair Salt Lake City, UT 84112 Email: austin.orr@utah.edu

Red Butte Creek Hydrologic Modeling Final Report 2012 Project Contributors: Fernanda Lobo Lindsay Minck Zach Magdol Austin Orr Kristianne Sandoval

Executive Summary This report documents the efforts to create a working model of the heavily urbanized river system that flows adjacent to the University of Utah Campus as it transitions from a protected natural watershed into one that is affected by the urbanization of Salt Lake City. In order to accurately simulate this river section, an extensive field survey was conducted to obtain river cross section and hydraulic feature data. This survey included 4 site visits, collection of over 30 cross sections, documentation of river features, and hundreds of person-hours. Preliminary results of the HEC-RAS model were found to be accurate. The model indicated roadway overtopping at the 900 South crossing during the 10yr storm event, largely due to the small culvert beneath the road. The flooding modeled is consistent with both the SL County report and site observations. The model correctly predicted the section of the river with the highest velocity, a section in Miller Park that was observed to have a concrete structure to secure the earthen slope because of actual bank erosion. The following is a list of key points: Thorough field studies yielded highly detailed observations throughout study area The model successfully reproduces known creek dynamics River system failures including roadway overtopping and excessive flow velocities occurred in more highly urbanized regions The model provides useful foundation for future planning level analysis Recommended future modeling efforts include inline detention to simulate the actual system capacity for storage. In addition, simulating unsteady flow behavior by including runoff hydrographs for the storm water outfalls would improve the accuracy and functionality of this model as a predictive tool.

Table of Contents Executive Summary... 2 Table of Contents... 3 Table of Figures... 4 Table of Tables... 4 Introduction & Background... 5 Methodologies... 6 Cross Section and Culvert data... 6 Geographical Representation Data... 7 Runoff Analysis... 7 Model Building... 10 Improvements and Recommendations... 19 Modeling Improvements... 19 Conclusion... 19 References... 20 Appendix 1.1 Red Butte Creek Overview... 21 Appendix 1.2 Urban Drainages... 22 Appendix 1.3 Miller Park Reach... 23 Appendix 1.4 Sunnyside Park Reach... 24 Appendix 1.5 Foothill Dr. to Connor Road Reach... 25 Appendix 1.6 Connor Road to Red Butte Gardens Reach... 26 Appendix 2 Field Notes and Observations... 27 Appendix 3 Culverts... 34 Appendix 4 Results Summary... 37 Appendix 5 Schedule... 43

Table of Figures Figure 1. Watershed used in StreamStats analysis... 8 Figure 2. Plan view of modeled portion of Red Butte Creek with river stations geo-referenced to aerial photography... 12 Figure 3. Culvert station 2.05 (E 900 South bridge) water surface profile for 5 year storm event... 14 Figure 4. Photo of upstream end of E 900 South culvert... 15 Figure 5. Modified 900 South culvert (4 foot pipe) with water surface profile for 100 year event... 15 Figure 6. Photo of Sunnyside Drive culvert inlet... 16 Figure 7. Water surface profile at Sunnyside Drive culvert for 10 year storm event... 17 Figure 8. Rating curve for river station 2.4... 17 Figure 9. Upstream view of river station 1.7 in Miller Park with retaining wall on left bank... 18 Table of Tables Table 1. Cost estimate from SL County study... 6 Table 2. Flow values for several return periods estimated by StreamStats... 8 Table 3. Rational Method flow volumes for urban drainages... 9 Table 4. Example cross section information for river station 2... 10 Table 5. Manning s n values used to estimate channel roughness... 11 Table 6. Flow in Red Butte Creek including urban runoff peak flow for steady flow analysis... 13

Introduction & Background The purpose of this project is to create, validate, and analyze a HEC-RAS model for Red Butte Creek between Red Butte Gardens and 1600 East. The Hydrologic Engineering Center River Analysis System (HEC-RAS) is a computer model released in 1995, developed by the United States Army Corps of Engineers (USACE) for use in river flow and floodplain analysis. According to its website, the stated goal of the Hydrologic Engineering Center (HEC) is to support the nation in its water resources management responsibilities. To this end, engineers use HEC-RAS for urban planning to assess the potential risk of flooding of waterways and determine how to mitigate this risk (Haestad Methods, 2007). HEC-RAS can be used to calculate water surface profiles, evaluate floodway encroachments, and determine the effects of obstructions such as bridges, culverts, and dams (HEC-RAS User s Manual, 2010). The goal in the development of a HEC-RAS model for Red Butte Creek is to not only provide a tool that could be used for all of the aforementioned in understanding the dynamics of the system, but to create a model for eventual use in prediction of the effect of planned changes in the current storm water management system of the adjacent contributing drainage areas. The section of Red Butte Creek analyzed in this project represents the first section of the river that is affected by urbanization. Red Butte Creek originates in a protected natural research area in the Wasatch Mountains just east of the University of Utah campus. As the creek flows through the campus and into Salt Lake City it transitions from this protected natural environment into a highly urbanized one. An aerial map of the region is shown in Appendix 1.1.The creek is constrained by encroaching urbanization as it flows through campus and Salt Lake City, eventually connecting with the Jordan River and then the Great Salt Lake. Red Butte Creek has been significantly altered by the increase in impervious surfaces that come with urbanization, by Red Butte Dam and its controlled releases, and by downstream water rights diversions. Precipitation that is naturally infiltrated and slowly released to the creek as ground water flows, now enters in surges causing dramatic flow fluctuations and the degradation of channel banks. Stormwater runoff heavy with sediment, nutrients, metals, and other pollutants, enters without the natural treatment provided by soils and vegetation. In 2008 Salt Lake City passed the Riparian Corridor Ordinance which resulted in funding for detailed studies of four city creeks included Red Butte Creek. Bio-West, Inc was selected to perform this study and completed the Salt Lake City Riparian Corridor Study in 2010. This study identified several issues affecting riparian function in Red Butte Creek, including invasive species, terrace erosion, and limited tree cover (BIO-WEST, 2010). From this study we were able to identify locations of river features that could not be directly accessed or may have gone unnoticed during field visits (e.g. locations of all stormwater outfalls). A determination was made, via queries to Salt Lake City and County employees, that the most current municipal model of Red Butte Creek was not only outdated but also only partially functional. This model was built in HEC-2, a predecessor to HEC-RAS, in 1993. The model and accompanying report titled Drainage Master Plan Report for 1300 South Outfall Area were 5

obtained from Salt Lake County. As the title suggests, this study specifically looked at the drainage areas contributing to one outfall along the Jordan River, with the goal of determining necessary systems improvements. Red Butte Creek is one of the Jordan River tributaries analyzed in this study. In this analysis HEC-1, which is another USACE model used for simulating runoff, was used in conjunction with HEC-2 to determine peak discharge rates for the 5, 10, and 10-year floods in order to determine existing drainage problems. This study specifically looked at the portion of Red Butte Creek from the Jordan River outfall to just east of Sunnyside Park, south of the Utah State Veteran s Affairs Building. The report found four main issues for the 10-year flood including overtopping at Sunnyside Avenue, overtopping at 900 south, capacity problems with the Red Butte conduit (west of 1100 east), and street flooding on Yalecrest Drive and Sunnyside Avenue. Solutions were recommended at a total cost of $903,000. See Table 1 for details regarding these recommendations. Table 1. Cost estimate from SL County study Methodologies Cross Section and Culvert data More than 30 cross sections have been surveyed by the team over a series of 4 visits to the publically accessible sections of Red Butte Creek within the section of interest shown in Appendix 1.1. The only area in which the creek is not well characterized is the section that runs through property owned by the Utah State Department of Veteran s Affairs (VA). This area was thus characterized primarily by its length and the assumption that its upstream and downstream cross sections are representative of the entire section. This also happens to be a section of the river where several stormwater outfalls contribute to the creek as discovered in the review of the SLC Riparian Corridor Study 2010. Save for the section owned by the VA, all culverts, diversion, and in-stream features such as waterfalls and foot bridges were also documented directly during field visits. Culvert dimensions, length estimates, and an understanding for existing flood mitigation features throughout the section have been collected and summarized in Appendix 2. 6

Geographical Representation Data Maps of the Red Butte Creek area were created in ArcMap 10 using the field data collected and the use of data available through the Utah Automated Geographic Reference Center (AGRC). The suite of maps created for this project is located in Appendix 1. Data was directly obtained for aerial photography, topography, stream location, stream gauge location and dam location. This data was input into maps of the Red Butte Creek and then manipulated where necessary to attain data useful to this project. Aerial photography included as the background of this project is projected at 6-inches. It is High Resolution Orthophotography obtained in 2012. The high resolution of the photography is important for this project because visual accuracy was needed to coordinate data inputs with field observations. Lower resolution aerial photography (projected at 1-meter) was used as background for surrounding areas not affecting this project. Flow into the Red Butte Creek from urban drainage and watershed runoff was calculated using the Rational Method as described in the Runoff Analysis section of this report. Topographic data was used in order to correlate data for each watershed to the location of the outfall that discharges into the Red Butte Creek. The topography was delineated for each watershed and then the calculated flow was associated with the corresponding outfall. Data collected in the field located outfalls and the watershed runoff was connected to this data. The flow data associated with each watershed was then input to the HEC-RAS model at outfall locations. Topographic data was also used to more correctly locate the streambed. The stream file downloaded from the AGRC website maps all the streams in the state of Utah. The Red Butte Creek was singled out for this project and a smaller file was created to conserve data space and make working with the map easier. The file acquired shows the Red Butte Creek approximate location, however, this project requires a more detailed and accurate stream path. The topographic data was utilized to adjust the streambed to align with elevations. The field data was also used in this process to correlate existing features with the visual representation of the aerial photos. The resulting stream file reflects a more accurate representation and can be used for calculations for the HEC-RAS modeling. Runoff Analysis The model simulates a combination of steady state flows through the Red Butte Creek channel. In order to better understand the hydraulic function of this channel across a variety of likely scenarios, flows have been estimated for three 24hr rainfall events: 5 year, 10 year, and 100 year. It is necessary to combine the inflows from the natural watershed with the periodic inflows resulting from urban stormwater runoff. These estimations were treated as two separate analyses whose superposition yields the flow values for model input. The United States Geological Survey (USGS) online tool StreamStats was used to determine 5- year, 10-year, and 100-year flows at the east end of Red Butte Creek, just below Red Butte Gardens. StreamStats uses watershed characteristics and regression equations from gaged stream 7

sites to estimate flow statistics at un-gaged sites. Figure 1 shows the StreamStats delineated watershed and Table 2 for the values calculated by StreamStats based on this watershed. There are two gage sites on Red Butte Creek. The first, managed by the USGS, is located upstream of Red Butte Reservoir. The second, managed by Salt Lake County Public Works, is located at 1600 East and Bonneview Drive. Figure 1. Watershed used in StreamStats analysis Table 2. Flow values for several return periods estimated by StreamStats Runoff from the urbanized areas that abut the creek was estimated using the Rational Method: Q = cubic feet per second (cfs) C = runoff coefficient (unit less) i = rainfall intensity (in/hr) A = contributing area (sqft) 8 Q = CiA

Rainfall intensity was determined using the NOAA Atlas 14 and is shown in Table 3. The calculation for contributing inflow from this type of analysis assumes a worst case scenario in which each runoff area is contributing its instantaneous peak flow for each respective storm. Flow modeling of this type is necessary for a steady state analysis of the potential for flooding in the channel. The necessary area information was determined using GIS ArcMap 10 and estimating which outfall to route the runoff water based on topography. GIS was also used to assign area weighted runoff coefficients between 0.75-0.95 for impervious surfaces that contribute to each outfall. The map used for these steps is shown in Appendix 1.2 Urban Drainages. The flow calculated using the rational method was added cumulatively to the baseflow estimated using StreamStats at the uppermost station. Table 3 contains a summary of the urban drainage area, C value, storm intensity, and resulting flow volume. Table 3. Rational Method flow volumes for urban drainages Urban Area 24 hr storm intensity 24 hr storm peak flow C Drainage ID i-5 i-10 i-100 Q-5 Q-10 Q-100 sqft in/hr in/hr in/hr cfs cfs cfs 0 248,650.6 0.90 0.078 0.088 0.126 0.404 0.456 0.653 1 539,793.3 0.79 0.078 0.088 0.126 0.765 0.863 1.236 2 80,086.4 0.90 0.078 0.088 0.126 0.130 0.147 0.210 3 57,798.2 0.83 0.078 0.088 0.126 0.086 0.097 0.139 4 230,675.0 0.83 0.078 0.088 0.126 0.344 0.388 0.555 5 190,080.3 0.83 0.078 0.088 0.126 0.283 0.319 0.457 6 192,296.3 0.86 0.078 0.088 0.126 0.297 0.335 0.480 7 234,256.9 0.85 0.078 0.088 0.126 0.360 0.406 0.581 8 84,352.6 0.80 0.078 0.088 0.126 0.122 0.137 0.197 9 172,853.1 0.86 0.078 0.088 0.126 0.267 0.301 0.431 10 141,675.0 0.85 0.078 0.088 0.126 0.217 0.245 0.351 11 138,314.7 0.85 0.078 0.088 0.126 0.212 0.239 0.343 12 112,136.5 0.90 0.078 0.088 0.126 0.182 0.206 0.294 13 159,649.1 0.88 0.078 0.088 0.126 0.254 0.286 0.410 14 55,129.4 0.80 0.078 0.088 0.126 0.080 0.090 0.129 15 62,757.1 0.75 0.078 0.088 0.126 0.085 0.096 0.137 16 142,840.6 0.85 0.078 0.088 0.126 0.219 0.247 0.354 17 223,235.3 0.90 0.078 0.088 0.126 0.363 0.409 0.586 18 39,782.3 0.80 0.078 0.088 0.126 0.057 0.065 0.093 19 102,039.4 0.82 0.078 0.088 0.126 0.151 0.170 0.244 A future HEC-RAS model could more accurately simulate each event by using a hydrograph to characterize each contributing basin inflow for both the natural watershed above Red Butte Gardens and for stormwater inputs from the urbanized areas. 9

Model Building The first step in creating a HEC-RAS model is to draw the reaches, which must be drawn upstream to downstream. One reach was used to model Red Butte Creek for this project, with no tributaries. Creek lengths and distances between cross sections were determined using aforementioned aerial photography and mapping data. The data needed to characterize each cross section was acquired during a series of site visits and field surveys. An example of the necessary information for a single cross section for this model is shown in Table 4. The location of this cross-section is shown in Appendix 1.3 Miller Park Reach and in Figure 2. Manning s n values were determined from field observations and tables provided in the HEC-RAS user s manual (see Table 5). Table 4. Example cross section information for river station 2 Down Stream Reach Length Reach Name River Station 245.3 Miller Park Lower 2 Mannin's n Station (x) Elevation LOB 0 4593.80 0.023 2.5 4591.25 Channel 3.4 4589.15 0.04 5.5 4589.00 ROB 15.2 4589.55 0.023 21.3 4590.20 28.5 4593.80 Six culverts were including in the model. Culvert cross section sizes were determined from field measurements. Approximate length, upstream and downstream invert elevation, distance from upstream cross section, and roadway high chord were determined using Google Earth. HEC-RAS requires two upstream and two downstream cross sections immediately adjacent to each culvert. The dimensions for the nearest up and downstream field measured cross sections were used. Manning s n values and entrance loss coefficients were determined from tables in the HEC-RAS user s manual;; all culverts are concrete with square edges not mitered to the slope so a n value of 0.011 and a loss coefficient of 0.5 were used. 10

Table 5. Manning s n values used to estimate channel roughness Results Steady Flow Results Figure 2 shows a plan view from HEC-RAS of the entire surveyed section of Red Butte Creek. River stationing begins at the upstream end (station 5.6) and ends downstream (station 1.1) over a total channel length of approximately 9500 feet (1.8 miles). A total of 6 culverts are included in the model as well. Appendix 3 shows the upstream and downstream channel cross sections and photos. 11

Figure 2. Plan view of modeled portion of Red Butte Creek with river stations geo-referenced to aerial photography 12

The 5, 10 and 100 year storm events including stormwater inflows at river stations along the surveyed reach were analyzed. Table 6 is a summary of the steady flow input data. Critical depth was used as the upstream and downstream boundary condition. When using this condition, HEC- RAS calculates the critical depth at each river station and uses this for determining the water surface profile. Mixed flow states (i.e., subcritical and supercritical) were analyzed. Normal flow and known water surface elevation boundary conditions could also be used in the future to analyze steady flow. Table 6. Flow in Red Butte Creek including urban runoff peak flow for steady flow analysis Steady Flow Profiles Sta. 5 yr cfs 10yr cfs 100yr cfs *5.6 67.60 90.10 164.00 5.5 68.16 90.73 164.90 4.7 69.43 92.16 166.95 4.5 69.77 92.55 167.51 4.3 70.31 93.15 168.37 4.2 71.23 94.19 169.86 4.1 72.26 95.36 171.53 3.1 72.48 95.60 171.88 *Baseflow according to StreamStats at Sta. 5.6 Appendix 4 shows the full data output tables for the steady flow analysis. An important model result is flooding at the E 900 South bridge. Figure 3 shows the water surface profile plot at this culvert. There are many factors leading to overtopping at the culvert. The culvert is a 2 foot circular pipe culvert which is much smaller than the other culverts in the model. The small culvert size backs water up at the upstream end to a depth great enough to flow over the roadway in the model. This most likely would not occur in reality. There is a large floodplain directly before the culvert which is not modeled. Figure 4 shows a photo of the upstream end of the culvert. While surveying this culvert, debris and flood damage was observed. 13

RBC Model Revised Plan: Plan 05 12/4/2012 Red Butte Creek Red Butte Creek8 Legend EG 5-yr Crit 5-yr WS 5-yr 4660 Ground 4650 Elevation 4640 4630 1100 1200 1300 1400 1500 Main Channel Distance Figure 3. Culvert station 2.05 (E 900 South bridge) water surface profile for 5 year storm event The HEC-2 model produced by the county also showed overtopping at the 900 South culvert. It is likely that this seldom happens in reality because: (1) the flows at this section of Red Butte Creek are significantly less than upstream because of the water right in Sunnyside Park and (2) the floodplain at the upstream end of the culvert may detain a large storm flow before overtopping. The cross section surveyed at the upstream end of the culvert only covers approximately 50 feet horizontally. A larger cross section should have been surveyed to more appropriately model the floodplain. An improvement to the model could be extending cross section data at river station 2.1 and using the ineffective flow function in HEC-RAS. Ineffective flow allows the user to model sections of channel where the downstream velocity approaches zero. In the case of the 900 South culvert, a large inline detention storage area could be modeled using this function and including more data. 14

Figure 4. Photo of upstream end of E 900 South culvert A modification was made to analyze flooding at this point the culvert size was changed from a 2 foot pipe to a 4 foot pipe and resulted in no overtopping for all three storm events. This is a costly solution and is not recommended, but it was analyzed in the model to visualize the water surface profile if a larger culvert had been installed. Figure 5 shows the water surface profile for the 100 year event with a 4 foot culvert at 900 South that shows that it does not overtop. RBC Model Revised Plan: Plan 05 12/4/2012 Red Butte Creek Red Butte Creek8 Legend EG 100-yr Crit 100-yr 4660 WS 100-yr Ground 4650 Elevation 4640 4630 4620 1100 1200 1300 1400 1500 Main Channel Distance Figure 5. Modified 900 South culvert (4 foot pipe) with water surface profile for 100 year event 15

Another exciting result from the steady flow analysis can be seen at the Sunnyside Drive culvert. This is also a location of high flooding as observed during the survey. The culvert is a 48 inch reinforced concrete pipe. Salt Lake County modified this inlet prior to 1993 by adding a 42 inch circular metal pipe and vertical drop upstream of the original culvert in an effort to use the upstream floodplain as a detention area. Then in 1993 the County recommended constructing a detention basin at this location to increase storage from 7 to 19 acre-ft. Further research into the exact modifications and what the storage capacity is at this point is a future step that will improve the model and understanding of its results. Figure 6 shows a photo of the culvert inlet as it exists now (December 2012). The HEC-RAS model results in the formation of a hydraulic jump downstream of the Sunnyside Drive culvert (Figure 7). As with the 900 South culvert, survey observations validate the model results. The channel downstream of the Sunnyside Drive culvert is concrete, rectangular and narrow for approximately 100 feet before transitioning back to a natural channel. During the survey, water staining was observed on this concrete wall and a possible jump was observed. This hydraulic jump is caused by a downstream condition, the transition from a smooth to a rough channel. As displayed in the water surface profile in Figure 7, the flow is supercritical through the Sunnyside culvert and then jumps to subcritical approximately 40 feet downstream of the culvert outlet. The 100 year storm event does not produce a hydraulic jump at this location because the velocity is high enough for the flow to remain supercritical throughout the smooth to rough transition. Figure 6. Photo of Sunnyside Drive culvert inlet 16

RBC Model Revised Plan: Plan 05 12/4/2012 Red Butte Creek Red Butte Creek8 Legend EG 10-yr 4675 Crit 10-yr WS 10-yr Ground 4670 Elevation 4665 4660 4655 1800 1900 2000 2100 2200 Main Channel Distance Figure 7. Water surface profile at Sunnyside Drive culvert for 10 year storm event Rating curves are another useful model output to visualize the results. For example, the hydraulic jump discussed above occurs just upstream of river station 2.4. The rating curve for this station (Figure 8) shows the water surface elevation vs. flow. This is a unique station because the maximum water surface does not occur at the peak flow for the same reason the hydraulic jump does not occur at the peak flow. RBC Model Revised Plan: Plan 05 12/4/2012 4659.0 4658.5 Legend W.S. Elev 4658.0 W.S. Elev 4657.5 4657.0 4656.5 4656.0 0 20 40 60 80 100 120 140 160 180 Q Total (cfs) Figure 8. Rating curve for river station 2.4 17

The highest velocity observed is at river station 1.7 in Miller Park during the 100 year storm event. The velocity is 17.42 feet per second (fps). River station 1.7 is approximately 250 feet downstream of the 900 South culvert. The photo in Figure 9 shows this location. The left bank is a concrete wall most likely installed to mitigate erosion and incising caused by high velocities. Currently there is a County project being done in Miller Park to restore native riparian vegetation in order to stabilize the banks. This further validates the HEC-RAS model and points to its usefulness in predicting likely locations of erosion, hydraulic jumps, and culvert overtopping. Figure 9. Upstream view of river station 1.7 in Miller Park with retaining wall on left bank Overall the model has performed as expected and the results have generally represented and validated survey observations and information collected during the literature review. Potential improvements to the model include: extending cross sections to incorporate floodplains, using the ineffective flow function in HEC-RAS, inputting inline storage area data, and completing the model for omitted sections of Red Butte Creek (e.g., between 1600 East and 1100 East and upstream of Red Butte Gardens). 18

Improvements and Recommendations Modeling Improvements The Montgomery Watson (SLC utilities) report addresses the fact that although there are no formal detention basins within the study section of Red Butte Creek, there is storage created at roadway crossings due to the elevated roadway relative to the creek bed. This report identifies five road crossing detention areas at 1300 East, 1500 East, 900 South, Sunnyside Avenue, and Foothill Drive and the relative volumes. The accuracy of the HEC-RAS model can be improved by adding in-line storage at roadway crossings. The analysis performed for this document modeled the inflows as maximum steady state contributions as result of three different 24hr storm events. To increase the accuracy of the simulation, hydrographs can be input at each of these outfall locations to better represent each event scenario in an unsteady flow condition. In addition, a future analysis could include simulations of shorter but more intense storm events (e.g., 3hr storm) to simulate a flooding scenario of even greater magnitude. When these changes are made, statistics from the Salt Lake County Gage at 1600 East the HEC- RAS modeled could be used to calibrate this model. Since new monitoring is being initiated as part of the iutah research effort calibration. This verification of the model would ensure the accuracy of any future analysis and improve its potential usefulness as a planning tool. Conclusion The HEC-RAS model created in this project for the section of Red Butte Creek from Red Butte Gardens to 1600 east can be used for simple analysis and planning. Moving forward the model can be refined and improved, to assist with future efforts to improve the health of the creek, overall water quality, and system sustainability through the implementation of green infrastructure for storm water control. Although the model should be further calibrated the preliminary results are promising and have been validated by observation. Overall the model showed more flooding and erosion prone areas in the downstream section of RBC. This is a reasonable result given the increase in impervious surfaces that leads to creek impairments such as incision and erosion, culvert overtopping, and bank instability. As discussed, the Sunnyside Drive and the 900 South culverts are areas of concern. Upstream changes to mimic natural hydrology, improvements to these physical structures, and increasing the capacity for inline storage could possibility mitigate these problems. This model can be used in determining the effects and benefits of future planning and decisions. 19

References Haestad Methods Water Solutions. 2007. Floodplain Modeling Using HEC-RAS. Exton, PA:Bentley Institute Press. Bio-West, Inc. 2010. Salt Lake City Riparian Corridor Study, Final Red Butte Creek Management Plan. Prepared for Salt Lake City Department of Public Utilities. US Army Corps of Engineers, Hydrologic Engineering Center. 2010. HEC-RAS River Analysis System, User s Manual. Montgomery Watson. 1993. Storm Drainage Master Plan of Salt Lake City for 1300 South Study Area. Prepared for Salt Lake City Department of Public Utilities US Army Corps of Engineers web page, Available from: http://www.hec.usace.army.mil/whoweare/whoweare.html 20

Appendix 1.1 Red Butte Creek Overview 21

Appendix 1.2 Urban Drainages 22

Appendix 1.3 Miller Park Reach 23

Appendix 1.4 Sunnyside Park Reach 24

Appendix 1.5 Foothill Dr. to Connor Road Reach 25

Appendix 1.6 Connor Road to Red Butte Gardens Reach 26

Appendix 2 Field Notes and Observations Reach Element River Sta. Notes Photographs Red Butte Gardens to Connor Road XS 6 5.6 Red Butte Gardens to Connor Road XS 5 5.5 Red Butte Gardens to Connor Road XS 4 5.4 rocks on the bed vegetation in the LB plants in the RB Red Butte Gardens to Connor Road Waterfall 2 Red Butte Gardens to Connor Road Waterfall 1 Red Butte Gardens to Connor Road XS 3 rocks on the bed vegetation in the LB 5.3 the RB Red Butte Gardens to Connor Road XS 2 the bed vegetation in the LB 5.2 Erosion in the RB 27

Reach Element River Sta. Notes Photographs the bed Red Butte Gardens to Connor Road XS 1 leaves 5.1 trees and brenchs Red Butte Gardens to Connor Road Connor Road Bridge Connor Road to Foothill Drive Stormwate r Outfall 1 Connor Road to Foothill Drive XS 8 4.8 Connor Road to Foothill Drive XS 7 4.7 Connor Road to Foothill Drive Bridge Connor Road to Foothill Drive XS 6 4.6 28

Reach Element River Sta. Notes Photographs Connor Road to Foothill Drive Culvert 1 Connor Road to Foothill Drive XS 5 4.5 Connor Road to Foothill Drive XS 4 4.4 LB steep A few 1' boulders in Connor Road to Foothill Drive Stormwate r Outfall Connor Road to Foothill Drive Culvert 2 4 ft drop 6.5 ft height, 5.5 ft 18" SD large overflow coming Connor Road to Foothill Drive XS 3 LB steep Exposed roots on RB 4.3 uniform bed w/ Connor Road to Foothill Drive XS 2 4.2 LB eroded narrow bed w/ 29

Reach Element River Sta. Notes Photographs 28" stormwater Connor Road to Foothill Drive Stormwate r Outfall 2 See photos (reference Connor Road to Foothill Drive XS 1 XS in tight meander LB flat and long 4.1 RB steep and eroded Bed is pebble - Connor Road to Foothill Drive Foothill Drive Culvert Large rectangular hieght = 6.5 ft width = 6 ft Connor Road to Foothill Drive Concrete Wall Obstruction Sunnyside Park VA Boundry Potential water right About 6 ft high, 12 ft Bridge just DS of Sunnyside Park Bridge steep and eroded LB Sunnyside Park XS 5 3.5 30

Reach Element River Sta. Notes Photographs LB and RB fairly Sunnyside Park XS 4 3.4 Bed is cobble See photos (reference Sunnyside Park Water Right Sunnyside Park XS 3 3.3 LB and RB fairly Bed is cobble Sunnyside Park XS 2 3.2 LB eroded with grass Channel deepers, Sunnyside Park Debris Gate Remnants of debris See photos (reference Sunnyside Park XS 1 LB has low grade Large rock (2.5') in 3.1 RB much much Sunnyside Park Culvert Upstream end of See photos (reference 31

Reach Element River Sta. Notes Photographs Miller Park Upper Sunnyside Drive Culvert 4' circular culvert Miller Park Upper XS 3 2.3 Miller Park Upper XS 2 2.2 Miller Park Upper XS 1 2.1 Miller Park Lower XS 8 Obvious flood Debris covering LB 1.8 Smooth exposed Debris and and Miller Park Lower Miller Park Lower XS 7 XS 6 Riprap along LB Large boulders (1.5') 1.7 Possible 3" SD Lots of debris 2 ft elevation drop RB concrete wall engineered channel 1.6 Lots of damage to Possible hydraulic 32

Reach Element River Sta. Notes Photographs Miller Park Lower XS 5 1.5 Miller Park Lower XS 4 1.4 Miller Park Lower XS 3 Large rock on RB Ivy covering all LB 1.3 Scattered medium Tight meander Miller Park Lower XS 2 Grassy RB Steep and eroded LB 1.2 Cobble in bed Miller Park Lower XS 1 1600 E gage location Concrete spillway 1.1 Downstream end of 33

Appendix 3 Culverts Elevation RS=5.05 Upstream (Culvert) 4916 4914 4912 4910 4908 4906 4904 4902 0 5 10 15 20 25 30 Legend Ground Bank Sta Elevation 4916 4914 4912 4910 4908 4906 RS=5.05 Downstream (Culvert) 4904 4902 0 5 10 15 20 25 30 Station Elevation 4846 4844 4842 4840 4838 RS=4.55 Upstream (Culvert) Legend Ground Bank Sta 4836 0 2 4 6 8 10 12 14 16 4846 RS=4.55 Downstream (Culvert) Elevation 4844 4842 4840 4838 4836 0 2 4 6 8 10 12 14 16 Station 34

Elevation RS=4.35 Upstream (Culvert) 4838 4836 4834 4832 4830 4828 4826 4824 0 2 4 6 8 10 12 14 16 18 Legend Ground Bank Sta Elevation 4838 4836 4834 4832 4830 4828 RS=4.35 Downstream (Culvert) 4826 4824 0 2 4 6 8 10 12 14 16 18 Station Elevation RS=4.05 Upstream (Culvert) 4780 4778 4776 4774 4772 4770 4768 4766 4764 0 5 10 15 20 25 Legend Ground Bank Sta Elevation RS=4.05 Downstream (Culvert) 4780 4778 4776 4774 4772 4770 4768 4766 4764 0 5 10 15 20 25 Station 35

Elevation RS=3.05 Upstream (Culvert) 4678 4676 4674 4672 4670 4668 4666 4664 4662 4660 0 2 4 6 8 10 12 14 16 18 Legend Ground Bank Sta Elevation RS=3.05 Downstream (Culvert) 4678 4676 4674 4672 4670 4668 4666 4664 4662 4660 0 2 4 6 8 10 12 14 16 18 Station Elevation RS=2.05 Upstream (Culvert) 4650 4648 4646 4644 4642 4640 4638 4636 0 10 20 30 40 50 Legend Ground Bank Sta Elevation 4650 4648 4646 4644 4642 4640 RS=2.05 Downstream (Culvert) 4638 4636 0 10 20 30 40 50 Station 36

Appendix 4 Results Summary Profile Output Table for 5, 10, 100 year storm with Critical Depth upstream and downstream boundary conditions River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 5.6 5-yr 67.6 4990 4991.28 4.83 13.99 20.17 1.02 1.29 5.6 10-yr 90.1 4990 4991.45 5.16 17.46 21.65 1.01 1.45 5.6 100-yr 164 4990 4991.87 6 27.35 25.08 1.01 1.87 5.5 5-yr 68.16 4975 4975.86 9.7 7.03 12.75 2.3 1.3 5.5 10-yr 90.73 4975 4975.98 10.52 8.63 14.79 2.43 1.46 5.5 100-yr 164.9 4975 4976.25 12.49 13.2 19.48 2.67 1.88 5.4 5-yr 68.16 4965 4966.45 5.18 13.15 16.31 1.02 1.45 5.4 10-yr 90.73 4965 4966.64 5.61 16.17 16.93 1.01 1.64 5.4 100-yr 164.9 4965 4967.12 6.67 24.72 18.24 1.01 2.13 5.39 5-yr 68.16 4958 4959.06 8.82 7.73 11.33 1.88 1.45 5.39 10-yr 90.73 4958 4959.21 9.62 9.43 13.11 2 1.65 5.39 100-yr 164.9 4958 4959.54 11.37 14.51 16.59 2.14 2.12 5.31 5-yr 68.16 4947 4948.39 6.26 10.89 11.42 1.13 1.47 5.31 10-yr 90.73 4947 4948.7 6.21 14.62 12.52 1.01 1.7 5.31 100-yr 164.9 4947 4949.31 7.22 22.83 14.61 1.02 2.32 5.3 5-yr 68.16 4940 4941.09 8.99 7.58 10.26 1.84 1.47 5.3 10-yr 90.73 4940 4941.15 11 8.25 10.53 2.19 1.71 5.3 100-yr 164.9 4940 4941.54 13 12.69 11.96 2.22 2.32 5.2 5-yr 68.16 4935 4936.48 5.99 11.39 10.31 1 1.48 5.2 10-yr 90.73 4935 4936.73 6.45 14.06 11.09 1.01 1.74 5.2 100-yr 164.9 4935 4937.4 7.44 22.18 13.16 1.01 2.41 5.1 5-yr 68.16 4922 4923.02 10.18 6.7 8.26 1.99 1.53 5.1 10-yr 90.73 4922 4923.18 11.27 8.05 8.66 2.06 1.85 5.1 100-yr 164.9 4922 4923.68 12.82 12.86 12.05 2.19 2.41 5.07 5-yr 68.16 4909 4909.87 12.42 5.49 7.89 2.62 1.53 5.07 10-yr 90.73 4909 4910.03 13.4 6.77 8.28 2.61 1.85 5.07 100-yr 164.9 4909 4910.48 15.35 10.74 9.4 2.53 2.41 5.06 5-yr 68.16 4907 4907.82 13.52 5.04 7.75 2.95 1.54 5.06 10-yr 90.73 4907 4907.96 14.6 6.21 8.12 2.94 1.85 5.06 100-yr 164.9 4907 4911.55 2.63 62.63 22.03 0.28 2.41 5.05 Culvert 5.04 5-yr 68.16 4902 4903.13 6.53 10.45 11.92 1.23 1.25 37

River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 5.04 10-yr 90.73 4902 4903.34 6.94 13.07 12.57 1.2 1.48 5.04 100-yr 164.9 4902 4903.98 7.65 21.54 13.82 1.08 2.06 5.03 5-yr 68.16 4901 4901.88 8.96 7.61 11.17 1.91 1.26 5.03 10-yr 90.73 4901 4902.04 9.59 9.46 11.66 1.88 1.48 5.03 100-yr 164.9 4901 4902.49 10.98 15.02 12.93 1.8 2.06 4.8 5-yr 68.16 4900 4900.83 9.72 7.01 11.01 2.15 1.26 4.8 10-yr 90.73 4900 4900.97 10.52 8.62 11.44 2.14 1.48 4.8 100-yr 164.9 4900 4901.38 12.19 13.53 12.68 2.08 2.06 4.7 5-yr 69.43 4877 4878.63 6.77 10.25 7.91 1.05 1.66 4.7 10-yr 92.16 4877 4878.89 7.47 12.34 8.09 1.07 1.94 4.7 100-yr 166.95 4877 4879.61 9.09 18.36 8.74 1.11 2.77 4.6 5-yr 69.43 4847 4847.99 14.13 4.91 7.64 3.1 1.72 4.6 10-yr 92.16 4847 4848.14 15.08 6.11 7.84 3.01 1.99 4.6 100-yr 166.95 4847 4848.59 17.01 9.82 8.55 2.8 2.74 4.57 5-yr 69.43 4839 4841.25 4.41 15.76 9.63 0.61 1.72 4.57 10-yr 92.16 4839 4841.84 4.25 21.67 10.42 0.52 1.99 4.57 100-yr 166.95 4839 4843.49 4.07 41 13.11 0.41 2.73 4.56 5-yr 69.43 4838.5 4841.28 3.29 21.1 10.35 0.41 1.72 4.56 10-yr 92.16 4838.5 4841.86 3.38 27.29 11.07 0.38 1.99 4.56 100-yr 166.95 4838.5 4843.51 3.48 48.03 14.06 0.33 2.73 4.55 Culvert 4.54 5-yr 69.43 4836.8 4838.63 4.2 16.53 11.12 0.61 4.54 10-yr 92.16 4836.8 4838.92 4.64 19.85 11.48 0.62 4.54 100-yr 166.95 4836.8 4839.75 5.61 29.74 12.74 0.65 4.53 5-yr 69.43 4836.7 4838.55 4.15 16.71 11.14 0.6 1.37 4.53 10-yr 92.16 4836.7 4838.84 4.61 20 11.5 0.62 1.62 4.53 100-yr 166.95 4836.7 4839.65 5.6 29.82 12.78 0.65 2.27 4.5 5-yr 69.77 4835 4836.37 6.02 11.59 10.52 1.01 1.37 4.5 10-yr 92.55 4835 4836.62 6.49 14.25 10.87 1 1.62 4.5 100-yr 167.51 4835 4837.28 7.75 21.62 11.67 1 2.28 4.4 5-yr 69.77 4827 4829.43 2.91 23.99 13.31 0.38 1.4 4.4 10-yr 92.55 4827 4830.01 2.88 32.08 14.95 0.35 1.64 4.4 100-yr 167.51 4827 4831.64 2.92 57.42 15.5 0.27 2.3 4.37 5-yr 69.77 4826.4 4829.41 2.17 32.16 14.96 0.26 4.37 10-yr 92.55 4826.4 4829.99 2.25 41.06 15.5 0.24 4.37 100-yr 167.51 4826.4 4831.63 2.52 66.5 15.5 0.21 38

River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 4.36 5-yr 69.77 4826.2 4829.41 1.99 35.14 15.5 0.23 1.4 4.36 10-yr 92.55 4826.2 4829.98 2.1 44.1 15.5 0.22 1.64 4.36 100-yr 167.51 4826.2 4831.63 2.41 69.54 15.5 0.2 2.31 4.35 Culvert 4.34 5-yr 69.77 4824 4825.3 5.96 11.71 11.05 1.02 1.3 4.34 10-yr 92.55 4824 4825.54 6.46 14.34 11.32 1.01 1.54 4.34 100-yr 167.51 4824 4826.2 7.49 22.36 13.07 1.01 2.2 4.33 5-yr 69.77 4823.1 4824.03 9.09 7.68 10.61 1.88 1.3 4.33 10-yr 92.55 4823.1 4824.21 9.68 9.56 10.81 1.81 1.54 4.33 100-yr 167.51 4823.1 4824.72 10.99 15.24 11.42 1.68 2.21 4.3 5-yr 70.31 4807 4808.24 6.37 11.04 10.97 1.12 1.32 4.3 10-yr 93.15 4807 4808.42 7.18 12.97 11.18 1.18 1.55 4.3 100-yr 168.37 4807 4808.88 9.17 18.37 12.09 1.31 2.21 4.2 5-yr 71.23 4792 4793.47 9.4 7.58 6.42 1.52 1.87 4.2 10-yr 94.19 4792 4793.78 9.84 9.58 6.69 1.45 2.19 4.2 100-yr 169.86 4792 4794.66 10.75 15.8 7.48 1.3 3.09 4.1 5-yr 72.26 4778 4779.62 6.06 11.92 10.61 1.01 1.62 4.1 10-yr 95.36 4778 4779.86 6.57 14.52 11.01 1.01 1.86 4.1 100-yr 171.53 4778 4780.52 7.79 22.01 11.79 1 2.52 4.07 5-yr 72.26 4772 4773.47 7.01 10.3 10.2 1.23 1.63 4.07 10-yr 95.36 4772 4773.66 7.72 12.36 10.72 1.27 1.86 4.07 100-yr 171.53 4772 4775.58 4.49 38.17 18.83 0.56 2.52 4.06 5-yr 72.26 4771.3 4773.45 4.08 17.7 11.35 0.58 1.62 4.06 10-yr 95.36 4771.3 4774.02 3.91 24.38 12.03 0.48 1.86 4.06 100-yr 171.53 4771.3 4775.65 3.23 53.17 20.23 0.35 2.51 4.05 Culvert 4.03 5-yr 72.26 4764.8 4765.6 17.43 4.15 8.13 4.3 1.62 4.03 10-yr 95.36 4764.8 4765.72 18.68 5.11 8.72 4.3 1.86 4.03 100-yr 171.53 4764.8 4766.37 15.15 11.32 10.46 2.57 2.51 4.02 5-yr 72.26 4764.5 4765.65 10.01 7.22 9.35 2.01 1.62 4.02 10-yr 95.36 4764.5 4765.77 11.38 8.38 9.68 2.16 1.86 4.02 100-yr 171.53 4764.5 4766.43 11.25 15.25 11.09 1.69 2.51 4.01 5-yr 72.26 4759 4760.62 6.08 11.89 10.61 1.01 1.63 4.01 10-yr 95.36 4759 4760.86 6.57 14.51 11.01 1.01 1.86 4.01 100-yr 171.53 4759 4761.48 7.95 21.59 11.75 1.03 2.52 3.6 5-yr 72.26 4705 4706.59 8.85 8.17 7.75 1.52 1.95 39

River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 3.6 10-yr 95.36 4705 4706.8 9.68 9.86 8.18 1.55 2.23 3.6 100-yr 171.53 4705 4707.4 11.34 15.12 9.38 1.57 3.02 3.5 5-yr 72.26 4696 4697.15 12.19 5.93 6.98 2.33 1.81 3.5 10-yr 95.36 4696 4697.35 13 7.33 7.41 2.3 2.1 3.5 100-yr 171.53 4696 4697.85 15.09 11.36 8.37 2.28 2.9 3.45 5-yr 72.26 4690 4691.81 6.57 11 8.3 1.01 1.81 3.45 10-yr 95.36 4690 4692.1 7.08 13.48 8.74 1 2.1 3.45 100-yr 171.53 4690 4692.84 8.35 20.54 10.31 1.04 2.9 3.4 5-yr 72.26 4689 4689.84 9.95 7.26 11.54 2.21 1.29 3.4 10-yr 95.36 4689 4689.97 10.82 8.82 12 2.22 1.5 3.4 100-yr 171.53 4689 4690.35 12.59 13.62 13.26 2.19 2.08 3.3 5-yr 72.26 4675 4676.59 5.81 12.45 12.2 1.01 1.6 3.3 10-yr 95.36 4675 4676.82 6.2 15.39 13.24 1.01 1.82 3.3 100-yr 171.53 4675 4677.43 7.1 24.17 15.96 1.02 2.43 3.2 5-yr 72.26 4671 4672.68 6.85 10.54 8.65 1.09 1.76 3.2 10-yr 95.36 4671 4672.95 7.35 12.98 9.39 1.1 2.05 3.2 100-yr 171.53 4671 4673.68 8.29 20.7 12.28 1.13 2.85 3.1 5-yr 72.48 4664 4667.35 1.71 42.32 16.5 0.19 1.46 3.1 10-yr 95.6 4664 4668.17 1.71 55.9 16.5 0.16 1.67 3.1 100-yr 171.88 4664 4673.09 1.25 137.03 16.5 0.08 2.25 3.07 5-yr 72.48 4663.5 4667.23 1.49 48.56 16.5 0.15 3.07 10-yr 95.6 4663.5 4668.07 1.53 62.55 16.5 0.14 3.07 100-yr 171.88 4663.5 4673.06 1.19 144.79 16.5 0.07 3.06 5-yr 72.48 4663.2 4667.22 1.36 53.44 16.5 0.13 1.45 3.06 10-yr 95.6 4663.2 4668.07 1.42 67.43 16.5 0.12 1.67 3.06 100-yr 171.88 4663.2 4673.06 1.15 149.72 16.5 0.07 2.25 3.05 Culvert 3.04 5-yr 72.48 4660 4661.8 5.85 12.39 11.8 1.01 1.8 3.04 10-yr 95.6 4660 4662.03 6.31 15.14 12.5 1.01 2.03 3.04 100-yr 171.88 4660 4662.62 7.63 22.53 12.5 1 2.62 3.03 5-yr 72.48 4659 4660.22 10.77 6.73 7.88 2.05 1.8 3.03 10-yr 95.6 4659 4660.45 11.03 8.67 9.24 2.01 2.03 3.03 100-yr 171.88 4659 4660.95 12.09 14.22 12.5 2 2.62 2.4 5-yr 72.48 4656 4658.5 3.44 21.05 12.5 0.47 1.8 2.4 10-yr 95.6 4656 4658.78 3.89 24.58 12.5 0.49 2.03 2.4 100-yr 171.88 4656 4657.92 12.47 13.78 12.5 2.09 2.62 40

River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 2.3 5-yr 72.48 4656 4657.81 5.84 12.42 11.81 1 1.8 2.3 10-yr 95.6 4656 4658.03 6.31 15.14 12.5 1.01 2.03 2.3 100-yr 171.88 4656 4658.62 7.63 22.53 12.5 1 2.62 2.2 5-yr 72.48 4648 4649.03 14.48 5.01 9.76 3.56 1.68 2.2 10-yr 95.6 4648 4649.15 15.11 6.33 10.97 3.51 1.87 2.2 100-yr 171.88 4648 4649.47 16.72 10.28 13.99 3.44 2.39 2.1 5-yr 72.48 4640 4649.32 0.31 237.11 43.48 0.02 1.5 2.1 10-yr 95.6 4640 4649.5 0.39 245.13 44.18 0.03 1.7 2.1 100-yr 171.88 4640 4649.89 0.65 262.64 45.66 0.05 2.24 2.07 5-yr 72.48 4638.5 4649.32 0.24 306.6 49.18 0.02 2.07 10-yr 95.6 4638.5 4649.5 0.3 315.65 49.5 0.02 2.07 100-yr 171.88 4638.5 4649.89 0.51 334.99 49.5 0.03 2.06 5-yr 72.48 4638 4649.32 0.22 331.34 49.5 0.01 1.5 2.06 10-yr 95.6 4638 4649.5 0.28 340.4 49.5 0.02 1.7 2.06 100-yr 171.88 4638 4649.89 0.48 359.74 49.5 0.03 2.24 2.05 Culvert 2.04 5-yr 72.48 4636 4636.94 5.18 13.98 16.86 1 0.94 2.04 10-yr 95.6 4636 4637.11 5.67 16.86 16.88 1 1.11 2.04 100-yr 171.88 4636 4637.58 6.92 24.85 16.92 1.01 1.58 2.03 5-yr 72.48 4635.5 4636.26 6.63 10.94 16.85 1.45 0.94 2.03 10-yr 95.6 4635.5 4636.4 7.21 13.25 16.86 1.43 1.11 2.03 100-yr 171.88 4635.5 4636.8 8.59 20.02 16.9 1.39 1.58 1.8 5-yr 72.48 4634 4634.93 5.23 13.87 16.86 1.02 0.94 1.8 10-yr 95.6 4634 4635.11 5.68 16.83 16.88 1 1.11 1.8 100-yr 171.88 4634 4635.58 6.92 24.85 16.92 1.01 1.58 1.7 5-yr 72.48 4619 4619.77 14.09 5.14 7.91 3.08 1.51 1.7 10-yr 95.6 4619 4619.91 15.28 6.26 8.31 3.1 1.77 1.7 100-yr 171.88 4619 4620.32 17.42 9.87 9.52 3.02 2.45 1.6 5-yr 72.48 4613 4614.35 6.25 11.6 9.67 1.01 1.35 1.6 10-yr 95.6 4613 4614.61 6.78 14.11 10.05 1.01 1.61 1.6 100-yr 171.88 4613 4615.25 8.23 20.88 10.99 1.05 2.32 1.5 5-yr 72.48 4603.83 4604.65 7.25 9.99 15.35 1.58 1.06 1.5 10-yr 95.6 4603.83 4604.76 8.14 11.74 15.67 1.66 1.24 1.5 100-yr 171.88 4603.83 4605.11 9.9 17.35 16.48 1.7 1.73 1.4 5-yr 72.48 4598 4599.11 5.38 13.47 14.99 1 1.11 41

River Station Profile Flow (cfs) Min Ch El W.S. Elev Vel. (ft/s) Area (sq ft) Top Width Fr # Crit Depth 1.4 10-yr 95.6 4598 4599.3 5.89 16.23 15.41 1.01 1.3 1.4 100-yr 171.88 4598 4599.82 6.98 24.62 16.61 1.01 1.82 1.3 5-yr 72.48 4593 4594.4 7.22 10.04 12.6 1.43 1.62 1.3 10-yr 95.6 4593 4594.56 7.91 12.08 13.13 1.45 1.83 1.3 100-yr 171.88 4593 4594.97 9.67 17.77 14.5 1.54 2.4 1.2 5-yr 72.48 4589 4590.24 5.09 14.25 18.44 1.02 1.24 1.2 10-yr 95.6 4589 4590.4 5.51 17.35 18.85 1.01 1.41 1.2 100-yr 171.88 4589 4590.79 6.94 24.78 19.78 1.09 1.86 1.1 5-yr 72.48 4580 4580.72 11.28 6.43 13 2.83 1.22 1.1 10-yr 95.6 4580 4580.82 12.43 7.69 13.46 2.9 1.4 1.1 100-yr 171.88 4580 4581.13 14.13 12.17 14.96 2.76 1.92 42

Appendix 5 RED BUTTE CREEK - PROJECT TIMESHEET 25-Sep 26-Sep 27-Sep 28-Sep 29-Sep 30-Sep 1-Oct 2-Oct 3-Oct 4-Oct 5-Oct 6-Oct 7-Oct 8-Oct 9-Oct 10-Oct 11-Oct 12-Oct 13-Oct 14-Oct 15-Oct 16-Oct 17-Oct 18-Oct 19-Oct 20-Oct 21-Oct 22-Oct 23-Oct 24-Oct 25-Oct 26-Oct 27-Oct 28-Oct 29-Oct 30-Oct 31-Oct 1-Nov 2-Nov 3-Nov 4-Nov 5-Nov 6-Nov 7-Nov 8-Nov 9-Nov 10-Nov 11-Nov 12-Nov 13-Nov 14-Nov 15-Nov 16-Nov 17-Nov 18-Nov 19-Nov 20-Nov 21-Nov 22-Nov 23-Nov 24-Nov 25-Nov 26-Nov 27-Nov 28-Nov 29-Nov 30-Nov 1-Dec 2-Dec 3-Dec 4-Dec 5-Dec 6-Dec 7-Dec TOTAL HOURS Phase 1: Existing and Initial Data 43 PROPOSAL DUE 10.5 Fernanda Lobo 1.5 1.5 Zach Magdol 0.5 1.5 2 Lindsay Minck 4 4 Austin Orr 2 1 3 Kristianne Sandoval 0 1A: Collect and synthesize existing information and data DUE 17 Fernanda Lobo 2.5 2.5 Zach Magdol 2.5 1.5 4 Lindsay Minck 2.5 2.5 Austin Orr 2.5 1.5 4 Kristianne Sandoval 2.5 1.5 4 1B: Preliminary analysis of data gaps DUE 5 Fernanda Lobo 1 1 Zach Magdol 1 1 Lindsay Minck 1 1 Austin Orr 1 1 Kristianne Sandoval 1 1 1C: Acquire Flow Data DUE 1.5 Zach Magdol 1.5 1.5 1D: Collect field data at D/S section DUE 9 Zach Magdol 3 3 Austin Orr 3 3 Kristianne Sandoval 3 3 Phase 2: Red Butte Creek Evaluation 51.5 2A: Determine additional locations for field investigation DUE 5 Fernanda Lobo 1 1 Zach Magdol 1 1 Lindsay Minck 1 1 Austin Orr 1 1 Kristianne Sandoval 1 1 2B: Collect field data at U/S section DUE 30.5 Fernanda Lobo 2 2 Zach Magdol 5 1.5 6.5 Lindsay Minck 5 2 1.5 8.5 Austin Orr 5 5 Kristianne Sandoval 5 2 1.5 8.5 2C: Use topographical maps to analyze DUE 4 Fernanda Lobo 0 Zach Magdol 0 Lindsay Minck 0 Austin Orr 2 2 Kristianne Sandoval 1 1 2 2D: Determine appropriate data for HEC-RAS model DUE DUE 12 Fernanda Lobo 0 Zach Magdol 1.5 1.5 3 6 Lindsay Minck 0 Austin Orr 3 2 5 Kristianne Sandoval 1 1 Phase 3: Build Preliminary HEC-RAS Model 57.5 3A: Initial HEC-RAS model DUE 32 Fernanda Lobo 5 4 1 1 1 1 4 5 3 1 26 Zach Magdol 2 2 Lindsay Minck 0 Austin Orr 2 2 Kristianne Sandoval 2 2 3B: Progress Report DUE 23.5 Fernanda Lobo 1 1 2 Zach Magdol 1 1 1.5 0.5 4 Lindsay Minck 1 2 2 2.5 7.5 Austin Orr 1 1 5 1 8 Kristianne Sandoval 1 1 2 3C: Flow Analysis DUE 2 Fernanda Lobo 0 Zach Magdol 0 Lindsay Minck 0 Austin Orr 2 2 Kristianne Sandoval 0 Phase 4: Analyze Impacts to Red Butte Creek 62.5 4A: Finalize HEC-RAS model DUE 20.5 Fernanda Lobo 0 Zach Magdol 4 1 1 2 3 11 Lindsay Minck 0 Austin Orr 1 1 Kristianne Sandoval 2 1.5 2 3 8.5 4B: Determine impacts by model input manipulation DUE 5 Fernanda Lobo 0 Zach Magdol 4 4 Lindsay Minck 0 Austin Orr 0 Kristianne Sandoval 1 1 4C: Final Report DUE 37 Fernanda Lobo 1 1 2 Zach Magdol 1 1.5 0.5 1.5 4.5 Lindsay Minck 3 5 2 10 Austin Orr 1.5 2 3 4 10.5 Kristianne Sandoval 1.5 2 2.5 4 10 214.5 Group Member Signatures Hours Austin Orr 47.5 Lindsay Minck 34.5 Zach Magdol 50.5 Fernanda Lobo 38 Kristianne Sandoval 44 214.5 TOTAL