APPENDIX I FLOODPLAIN ANALYSIS

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1 APPENDIX I FLOODPLAIN ANALYSIS

TECHNICAL MEMORANDUM Date: June 11, 2014 To: Bibiana Alvarez and Ryan Lee Sawyer, Analytical Environmental Services From: Melanie Carr, MS, PE, Tarick Abu- Aly, MS, PE, Rafael Rodriguez, cbec

eco engineering (cbec) was contracted by Analytical Environmental Services (AES) on behalf of the City of Shasta (City) to perform a floodplain analysis for the Wastewater Treatment Facility (WWTF).

2 TECHNICAL MEMORANDUM Date: June 11, 2014 To: Bibiana Alvarez and Ryan Lee Sawyer, Analytical Environmental Services From: Melanie Carr, MS, PE, Tarick Abu- Aly, MS, PE, Rafael Rodriguez, cbec Reviewed by Kevin Coulton, CFM, PE Project: Subject: City of Shasta Lake WWTF Floodplain Analysis cbec, inc. eco engineering (cbec) was contracted by Analytical Environmental Services (AES) on behalf of the City of Shasta (City) to perform a floodplain analysis for the Wastewater Treatment Facility (WWTF). The purpose of this floodplain analysis is to evaluate the effect, if any, of proposed additional WWTF flows on localized floodplains by determining whether the proposed flows would contribute to either an increase in Water Surface Elevation (WSE) in Churn Creek or its unnamed tributary or expansion of the existing floodplain. cbec performed data collection and review, hydrologic analysis, and hydraulic modeling in support of this analysis. The results of the floodplain analysis indicate that the proposed additional WWTF flows will cause no increases to WSEs and floodplain extents at nearly all locations along the creeks and negligible increases (0.01- foot, inch) at a limited number of locations. The following information has been developed in support of the floodplain analysis: Background Assumptions Methods Results and Discussion Conclusion 1

3 Background The background section is comprised of Study Area Extents and WWTF Discharges. Study Area Extents The WWTF is located southwest of the City of Shasta Lake, on the right bank (western) side, downstream of the confluence of Churn Creek and Nelson Creek. The floodplain analysis was developed for Churn Creek and an unnamed tributary to Churn Creek proximal to the WWTF. The study area is shown in Figure 1. The WWTF has two discharge points: Discharge Point 001, located on the right bank approximately 100 feet downstream of the bridge on Churn Creek, and Discharge Point 002, which is located at the upstream end of the unnamed tributary to Churn Creek. The study was limited to approximately 500 feet upstream of the Discharge point 001, or 400 feet upstream of the bridge over Churn Creek near the WWTF. The downstream extent of the study is approximately 500 feet downstream of the confluence between Churn Creek and the unnamed tributary to Churn Creek. WWTF Discharges The WWTF treats and discharges effluent to Churn Creek at two locations: Discharge Point 001 and 002. Additional information regarding the WWTF is found in the WWTF Development Design Report (DDR) (Waterworks, 2013). The WWTF currently discharges at 10:1 dilution at Discharge Point 001, which is shown in Figure 1. WWTF staff read a stage gauge on the bridge pier upstream of Discharge Point 001 and use a rating curve to determine if sufficient flow is available for WWTF discharges to achieve the 10:1 dilution. If Churn Creek flows do not provide 10:1 dilution at the time of discharge, then flow is routed to effluent storage, until it can be land applied or discharged at Point 002. The City proposes to increase discharge flows at Discharge Point 001, and also cease discharge at Discharge Point 002. The concern is that the increased discharge flows might impact the floodplain. Additionally, infiltration and inflow (I&I) is a significant issue at the WWTF. When substantial rainfall occurs, runoff flows into the wastewater collection system to a large extent, thus exacerbating the effect of increased flows. ASSUMPTIONS The following assumptions were used in development of the WWTF Floodplain Analysis. The analysis would need to be revised upon changing any of the following assumptions: Proposed discharge 001 will be located at the existing discharge 001 location Discharge at 002 will be abandoned under the proposed condition 2

4 The flow scenarios studied are based on regression equations derived from streamflow data for 10- year, 50- year, and 100- year return periods. WWTF has minimal storage available. For purposes of this analysis, additional storage was assumed to be zero because during extreme wet years, antecedent moisture conditions would be saturated and it is likely that no storage would be available. This adds to the conservative nature of this analysis. Hydraulic model output is valid only within the extent of the study area. The effect of the WWTF flow on localized flooding is proximal to the WWTF. The study does not include any upstream analysis near Lake Shasta. This study does not include catastrophic levee failure of the storage pond, which is addressed elsewhere (SHN Consultants, 2001). It should be noted that the storage basin will be abandoned as part of the proposed project. METHODS Methods for developing the following components of the floodplain analysis are provided as follows: WWTF Flows Hydrology Precipitation Analysis Field Data Collection HECRAS Model Development WWTF Flows The WWTF DDR and WWTF discharge data were reviewed to develop the existing and proposed WWTF discharges for the floodplain analysis. The WWTF Design Report summarized WWTF flows from 2006 to 2012, while the WWTF discharge data was from 1995 to Additional discharge data was reviewed based on the relatively dry years that have occurred in the past five or so years to obtain variation in I&I flows into the WWTF during wet years. Table 1 displays the existing and proposed WWTF flows. Existing condition flows were identified using historical WWTF data. The proposed condition flows were identified in the WWTF DDR. It should be noted that the maximum influent pump capacity is 10.4 mgd; however, this flowrate has never been measured at the WWTF, and it is an instantaneous maximum and would only occur for short durations of time, on the order of an hour or so. Therefore, this value was not used as the maximum daily flow through the WWTF. 3

5 Table 1. Existing and Proposed WWTF Discharge Flows Item Discharge 001 Flow Discharge 002 Flow Discharge 001 Flow Discharge 002 Flow Hydrology Existing/ Proposed Condition Existing Existing Proposed Proposed Type mgd cfs Maximum daily flow Maximum daily flow peak hourly flow (5,464 gpm for 24 hours) Maximum daily flow Hydrology was developed for both Churn Creek and the unnamed tributary to Churn Creek proximal to the WWTF. Hydrology was developed using Streamstats (USGS), which determines watershed area using GIS and uses regional regression equations based on local stream gauges to yield peak discharge. Table 2 provides the peak discharge for the 10-, 50-, and 100- year events. Table 2. Peak discharge for Churn Creek and Unnamed Tributary Watershed Name Watershed Area Percent Impervious Mean Annual Precipitation (MAP) Peak Discharge, cfs Sq. miles % inches 10- Year 50- Year 100- Year Churn Creek ,290 3,990 4,990 Unnamed Tributary The peak flows are estimates, and there is potential for error in these values. Therefore, two comparisons were made to verify the peak flows. Upon review of the FEMA Flood Insurance Study (FIS) for the City of Shasta Lake, the FEMA 100- year flow is 6,400 cfs at 8.1 square miles, or 790 cfs/sq. mile. Our estimate of peak flow is 4,990 cfs at 7.8 square miles if 640 cfs/sq. mile, which is within the reasonable range of flows. Additionally, an historical USGS streamflow gauge that is no longer active (USGS ) was evaluated. The minimal available data included an historic peak flow of 4,860 cfs, measured in 1959, which is very similar to our estimates. In summary, the hydrology developed for this analysis has been verified as reasonable by two independent sources. 4

6 It should also be noted that the focus of this study is to quantify the relative difference between existing and proposed conditions, and not absolute values. Precipitation Analysis The WWTF DDR included discharge flows from 2006 to An additional precipitation analysis was performed to determine whether the flows from 2006 to 2012 used in the WWTF design report were representative of flow conditions during a wet year. The Shasta Dam Precipitation Gauge (CDEC, SHA) and Redding Municipal Airport Precipitation Gauge (NOAA/ KRDD) data were evaluated. Mean annual precipitation (MAP) from these gauges was 61 inches (SHA) and inches (KRDD), respectively. MAP from the Churn Creek watershed is 57.3 in, and therefore is more similar to Shasta Dam data. Data from the KRDD station were also used in the DDR report. KRDD data from the Redding airport exhibits drier conditions than Shasta Dam, and each are relatively the same distance from the area of interest. There are other nearby additional gauges that have started in recent years; however, these data were not used in the analysis due to their short length of record. Based on a review of the Shasta Dam rainfall data, 2010 rainfall was approximately a 10- Year Rainfall year, which means that substantial rainfall occurred that year. The remaining years used in the DDR report are some of the driest years on record. A 50- year rainfall year occurred during 1998; therefore, flow records from 1995 to present were evaluated to determine peak flow because they included high precipitation years that would have substantial I&I. However, it should be noted that the WWTF inflow might have been less during that time (15 years ago), and in future rainfall events, I&I could be slightly greater than historical data suggests. Field Data Collection Topographic and bathymetric data were collected to inform one- dimensional (1D) hydraulic modeling efforts for the proposed project. A detailed topographic survey was undertaken so that the existing conditions model and subsequent design iterations reflected current site conditions. cbec collected foot- based RTK GPS data of Churn Creek on April 7, cbec staff collected data along 23 cross sections, at a spacing of about 300 feet, on Churn Creek and the unnamed tributary to Churn Creek. The data collected data was integrated with other surface data described below to generate the topographic surface for the model. HEC- RAS Model Development A steady- state, one- dimensional Hydrologic Engineering Center River Analysis System (HEC- RAS) modeling was used for this analysis, which is appropriate for this level of effort. It can be used as a screening tool for determining potential effects, if any, to the 5

7 floodplain proximal to the WWTF. If the results from this analysis yielded a substantial increase in WSE and overtopping of banks, then a 2- dimensional study would be needed to determine actual extents of floodplain expansion. However, the WSEs in this study did not increase and therefore additional study is not warranted. HEC- RAS model development includes developing the model geometry and boundary conditions. Model Geometry A 1D of the existing conditions was created using HEC- RAS. The geo- referenced cross- sections and streamlines were created using the HEC- GeoRAS toolset in Arc- GIS, and cross section elevations were interpolated from the existing conditions topographic surface. The model was run using HEC- RAS version Topographic and bathymetric survey data collected in the field was augmented with two USDA NRCS Digital Elevation Models (DEMs) (USDA) that included overbank elevations far above the channel. This process enabled the model geometry to contain extremely high flows. These two DEMs had the NAD_1983_UTM_Zone_10N spatial reference and D_North_American_1983 vertical datum. The final Triangular Irregular Network (TIN) surface was created mainly from the cbec survey data and two overbank points on either side of the channel for each cross section. This TIN was then used to create cross sections that were subsequently imported into HEC- RAS for 1D modeling. Using the geo- referenced cross sections and streamlines, which were imported from Arc- GIS, a model geometry was built in HEC- RAS. The Pine Grove Ave bridge was added near the upstream end of the model at river station 4433 to visualize the water surface elevation at this crossing. A lateral structure was added by cbec staff to the model from river station 500 to river station 2140 on the right bank of the upper reach of churn creek. The land between the two channels is only five feet higher than the top of bank for the first 1000 feet upstream of the confluence. Thus, adding the lateral structure enables water to flow from one channel to the other during high flows where this center mound is overtopped. This addition helps to visualize the length of the confluence during high flows. Cross- sections were interpolated at 200- foot intervals between existing cross sections in order to help smooth out the water surface profile. Roughness coefficients of 0.03 were used for the channel and 0.07 for the overbank areas. These n values are similar to those found in the Shasta Lake FIS. 6

8 Boundary Conditions Downstream boundary conditions were established using normal depth, and upstream boundaries were established using flows derived from the calculated hydrology. Table 3 displays the flows that were used in the HEC- RAS model. Table 3. Hydraulic model input for existing and proposed conditions Item Type cfs Existing Conditions Churn Creek Flow 100- Year flow 4, Year flow 3, Year flow 2,290 Unnamed tributary to 100- year flow 840 Churn Creek 50- Year flow Year flow 364 Discharge 001 Flow Maximum daily flow 6.22 Discharge 002 Flow Maximum daily flow Proposed Conditions Churn Creek Flow 100- Year flow 4, Year flow 3, Year flow 2,290 Unnamed tributary to 100- year flow 840 Churn Creek 50- Year flow Year flow 364 Discharge 001 Flow peak hourly flow for hours Discharge 002 Flow Maximum daily flow 0 RESULTS AND DISCUSSION The results and discussion section includes the following elements: Existing and Proposed Conditions Low Flow Model Calibration Sensitivity Analysis 7

9 Existing and Proposed Conditions Steady- state model runs were developed for existing and proposed conditions for the 10-, 50-, and 100- year peak discharge flow. The differences between the existing and proposed conditions were the increase in WWTF flow at Discharge 001 (which was simulated at river station 4294 of the main channel) and the removal of flow from Discharge 002 (which was simulated at river station 2457 of the tributary). Figures 2, 3, and 4 display the creek bed and hydraulic profile for both Churn Creek and the unnamed tributary under the 10-, 50-, and 100- year flow scenarios, respectively. The existing and proposed WSEs appear generally the same for each scenario; however, tabular output data has a limited number of locations where the WSE increased by 0.01 feet, which is a negligible increase. Appendix A provides the model output data, which shows the exact locations of the negligible increases. No effect was measured on increase in extent of floodplain. Figures 5-10 depict cross sections along Churn Creek and the unnamed tributary displaying existing and proposed WSEs for 10-, 50-, and 100- year events. Note again that there the figures appear to have no change from existing to proposed conditions, but tabular output data has a limited number of locations where the WSE increased by 0.01 feet, which is a negligible increase. Model output is provided in Appendix A to show locations where the negligible increase occurs. No effect was measured on increase in extent of floodplain. Low Flow Model Calibration A low flow model calibration was performed in the channel. During the field reconnaissance and topographic/ bathymetric data collection, the WSE was measured. The stage gauge on the bridge was measured at that particular day and time, and the rating curve was used to determine the flow in Churn Creek. This flow was input into the model, and yielded a WSE within tenths of a foot to the actual measured WSE. No high water marks were available for comparison of larger flow events. Sensitivity Analysis A sensitivity analysis was performed based on maximum flow recorded in Churn Creek from the WWTF stage gauge, which was approximately 500 cfs. Note that this value is an order of magnitude less than the 100- year peak flow of 4,990 cfs. Under this scenario, the WWTF discharge would comprise a larger percentage of Churn Creek flow under both existing and proposed conditions. Results from this model run indicate that there is a negligible increase at a few locations in Churn Creek or tributary WSEs and no changes to floodplain extent. Based on the results of this analysis, the floodplain analysis is conservative in nature, and the Churn Creek discharge is not very sensitive to changes in WWTF discharge during extended large wet weather events. 8

10 CONCLUSION A conservative approach was used to adequately demonstrate that the proposed additional WWTF flows will cause no increases to WSEs and floodplain extents at nearly all locations along the creeks and negligible increases (0.01- foot, inch) at a limited number of locations. 9

11 REFERENCES California Data Exchange Center (CDEC). Shasta Dam Precipitation Data. Station SHA Data. Accessed April/ May City of Shasta Lake WWTF Discharge Data Developed by WWTF staff. Federal Emergency Management Agency Flood Insurance Study for City of Shasta Lake, California, Shasta County. National Oceanic and Atmospheric Administration (NOAA). REDDING MUNICIPAL AIRPORT CA US. Station KRDD Data. Accessed April/ May SNH Engineers and Consulting Geologists Inundation Map of City Wastewater Reclamation Reservoir. May. United States Army Corps of Engineers Hydraulic Engineering Center HEC- RAS River Analysis System Hydraulic Reference Manual. November. United States Department of Agriculture (USDA) Natural Resources Conservation Services (NRCS). ned10m40122f3.tif and ned10m40122f4.tif. Accessed April / May United States Geological Survey. Streamstats. Accessed in April/May Waterworks Engineers City of Shasta Lake Wastewater Treatment Facility Improvements for Direct Discharge to Churn Creek, Development Design Report Final Draft, Prepared by, May 8,

12 FIGURES

$14-1008 Created By: RR Figure 1 R:\Projects\14-1008_City of Shasta Lake WWTP$

13 Notes: City of Shasta Lake Waste Water Treatment Plant Plan View Project No Created By: RR Figure 1 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_1.docx 6/9/2014

14 Notes: City of Shasta Lake WWTP Upgrade Q10 Profile View Project No Created By: RR Figure 2 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_2 6/7/2014

15 Notes: City of Shasta Lake WWTP Upgrade Q50 Profile View Project No Created By: RR Figure 3 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_3 6/7/2014

16 Notes: City of Shasta Lake WWTP Upgrade Q100 Profile View Project No Created By: RR Figure 4 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_4 6/7/2014

17 Churn_Creek Plan: Final_Existing_Updated 6/2/2014 River = Churn Reach = Upper RS = Legend WS Proposed (Q100) WS Existing (Q100) WS Proposed (Q50) WS Existing (Q50) WS Proposed (Q10) WS Existing (Q10) Ground Bank Sta 715 Elevation (ft) Station (ft) Notes: City of Shasta Lake WWTP Upgrade Churn Creek: River Station 4475 Project No Created By: RR Figure 5 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_5 6/2/2014

18 Churn_Creek Plan: Final_Existing_Updated 6/2/2014 River = Churn Reach = Upper RS = Legend WS Proposed (Q100) WS Existing (Q100) WS Proposed (Q50) WS Existing (Q50) WS Proposed (Q10) WS Existing (Q10) Ground Bank Sta Elevation (ft) Station (ft) Notes: City of Shasta Lake WWTP Upgrade Churn Creek: River Station 4294 Project No Created By: RR Figure 6 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_6 6/2/2014

19 Churn_Creek Plan: Final_Existing_Updated 6/2/2014 River = Churn Reach = Upper RS = Legend WS Proposed (Q100) WS Existing (Q100) WS Proposed (Q50) WS Existing (Q50) WS Proposed (Q10) WS Existing (Q10) Ground Bank Sta Elevation (ft) Station (ft) Notes: There is a lateral structure on the river right side of this cross section that allows overbank flow from this channel to flow laterally into the tributary. City of Shasta Lake WWTP Upgrade Churn Creek: River Station 1034 Project No Created By: RR Figure 7 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_7 6/2/2014

20 Churn_Creek Plan: Final_Existing_Updated 6/2/2014 River = Churn Reach = Lower RS = Legend WS Proposed (Q100) WS Existing (Q100) WS Existing (Q50) WS Proposed (Q50) WS Existing (Q10) WS Proposed (Q10) Ground Bank Sta 685 Elevation (ft) Station (ft) Notes: City of Shasta Lake WWTP Upgrade Churn Creek: River Station 269 Project No Created By: RR Figure 8 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_8 6/2/2014

21 Churn_Creek Plan: Final_Existing_Updated 6/7/2014 River = R002 Reach = Tributary RS = Legend WS Existing (Q100) WS Proposed (Q100) WS Existing (Q50) 720 WS Proposed (Q50) WS Proposed (Q10) WS Existing (Q10) Ground Bank Sta 710 Elevation (ft) Station (ft) Notes: City of Shasta Lake WWTP Upgrade Tributary: River Station 1914 Project No Created By: RR Figure 9 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_9 6/7/2014

22 Churn_Creek Plan: Final_Existing_Updated 6/2/2014 River = R002 Reach = Tributary RS = Legend WS Existing (Q100) WS Proposed (Q100) WS Existing (Q50) WS Proposed (Q50) WS Proposed (Q10) WS Existing (Q10) Ground Bank Sta Elevation (ft) Station (ft) Notes: There is a lateral structure on the river right side of this cross section that allows overbank flow from the main channel to flow laterally into this channel. City of Shasta Lake WWTP Upgrade Tributary: River Station 424 Project No Created By: RR Figure 10 R:\Projects\ _City of Shasta Lake WWTP Upgrade\Figures\Figure_10 6/2/2014

23 APPENDIX A: MODEL OUTPUT

24 Profile Output Table - Standard Table 1 HEC- RAS Plan: Up # Rivers = 2 # Hydraulic Reaches = 3 # River Stations = 49 # Plans = 1 # Profiles = 6 River Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10)

25 Profile Output Table - Standard Table 1 HEC- RAS Plan: Up # Rivers = 2 # Hydraulic Reaches = 3 # River Stations = 49 # Plans = 1 # Profiles = 6 River Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) R002 Tributary * Existing (Q10) R002 Tributary * Proposed (Q10) R002 Tributary * Existing (Q50) R002 Tributary * Proposed (Q50) R002 Tributary * Existing (Q100) R002 Tributary * Proposed (Q100) R002 Tributary Existing (Q10) R002 Tributary Proposed (Q10) R002 Tributary Existing (Q50) R002 Tributary Proposed (Q50) R002 Tributary Existing (Q100) R002 Tributary Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper Bridge Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10)

26 Profile Output Table - Standard Table 1 HEC- RAS Plan: Up # Rivers = 2 # Hydraulic Reaches = 3 # River Stations = 49 # Plans = 1 # Profiles = 6 River Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50)

27 Profile Output Table - Standard Table 1 HEC- RAS Plan: Up # Rivers = 2 # Hydraulic Reaches = 3 # River Stations = 49 # Plans = 1 # Profiles = 6 River Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper 2139 Lat Struct Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper * Existing (Q10) Churn Upper * Proposed (Q10) Churn Upper * Existing (Q50) Churn Upper * Proposed (Q50)

28 Profile Output Table - Standard Table 1 HEC- RAS Plan: Up # Rivers = 2 # Hydraulic Reaches = 3 # River Stations = 49 # Plans = 1 # Profiles = 6 River Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft) Churn Upper * Existing (Q100) Churn Upper * Proposed (Q100) Churn Upper Existing (Q10) Churn Upper Proposed (Q10) Churn Upper Existing (Q50) Churn Upper Proposed (Q50) Churn Upper Existing (Q100) Churn Upper Proposed (Q100) Churn Upper 1034 Existing (Q10) Churn Upper 1034 Proposed (Q10) Churn Upper 1034 Existing (Q50) Churn Upper 1034 Proposed (Q50) Churn Upper 1034 Existing (Q100) Churn Upper 1034 Proposed (Q100) Churn Upper 500 Existing (Q10) Churn Upper 500 Proposed (Q10) Churn Upper 500 Existing (Q50) Churn Upper 500 Proposed (Q50) Churn Upper 500 Existing (Q100) Churn Upper 500 Proposed (Q100) Churn Lower Existing (Q10) Churn Lower Proposed (Q10) Churn Lower Existing (Q50) Churn Lower Proposed (Q50) Churn Lower Existing (Q100) Churn Lower Proposed (Q100) Churn Lower * Existing (Q10) Churn Lower * Proposed (Q10) Churn Lower * Existing (Q50) Churn Lower * Proposed (Q50) Churn Lower * Existing (Q100) Churn Lower * Proposed (Q100) Churn Lower Existing (Q10) Churn Lower Proposed (Q10) Churn Lower Existing (Q50) Churn Lower Proposed (Q50) Churn Lower Existing (Q100) Churn Lower Proposed (Q100)

The Basics. HECRAS Basis Input. Geometry Data - the basics. Geometry Data. Flow Data. Perform Hydraulic Computations. Viewing the Output

The Basics. HECRAS Basis Input. Geometry Data - the basics. Geometry Data. Flow Data. Perform Hydraulic Computations. Viewing the Output The Basics HECRAS Basis Input Geometry Data. Flow Data. Perform Hydraulic Computations by G. Parodi WRS ITC The Netherlands Viewing the Output ITC Faculty of Geo-Information Science and Earth Observation