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HomeMy WebLinkAbout6608; Northwest Quadrant Drainage Improvements; NW Quad Drainage - Valley St/Ocean St/Highland DR/Linda Ln; 2013-10-18 FINAL SUBMITTAL – OCTOBER 18, 2013 Table of Contents 1. Project Description .................................................................................................... 1  1.1 Project Background ............................................................................................ 1  1.2 Project Location .................................................................................................. 1  1.3 Existing Conditions ............................................................................................. 3  2. Study Objectives ....................................................................................................... 4  3. Methodology .............................................................................................................. 4  3.1 Hydrology ............................................................................................................ 4  3.2 Hydraulics ........................................................................................................... 5  3.2.1 Street Capacity ............................................................................................ 5  3.2.2 Storm Drain Sizing ....................................................................................... 5  3.2.3 Inlet Sizing ................................................................................................... 5  4. Results ...................................................................................................................... 6  4.1 Hydrology ............................................................................................................ 6  4.2 Hydraulics ........................................................................................................... 7  5. Conclusions and Recommendations ......................................................................... 7  6. References .............................................................................................................. 10  List of Tables Table 4-1 Hydrology Summary ......................................................................................... 6  Table 4-2 Street Capacity Summary ................................................................................. 7  List of Figures Figure 1-1 Vicinity Map ..................................................................................................... 2  Appendix APPENDIX A - NRCS Soils Information and FEMA Maps  APPENDIX B – Existing Condition Hydrology Maps  APPENDIX C - Existing Condition Street Capacity Calculations  APPENDIX D – Proposed Condition Pipe and Inlet Calculations  Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 1 1. Project Description 1.1 Project Background This project represents a portion of the overall plan for drainage improvements in Carlsbad’s Northwest Quadrant. Each site has experienced historically observed flooding conditions. Local residents have, in some instances, expressed concern regarding the extent and nature of drainage issues. The project’s overall goal is to alleviate, to the greatest extent practical, current deficiencies in drainage and resulting inundation. RBF has been hired by the City to identify the source of these deficiencies and work with staff to develop and implement design solutions. 1.2 Project Location The specific locations that are being addressed in this phase of work can be seen on the Vicinity Map (Figure 1-1):  3065 Ocean Street (Site 6) Ponding and inadequate drainage has been observed in front of the residence at 3065 Ocean Street. This residence is approximately 300’ south of the intersection with Carlsbad Village Drive.  Valley Street and Buena Vista Way (Site 7) Ponding and inadequate drainage have been observed on the east side of Valley Street approximately 50’ south of the intersection with Buena Vista Way. Sheet flow has also been observed crossing Buena Vista Way approximately 100’ east of the Valley Street intersection. This portion of Valley Street is considered an “Alternative Design”, based upon “the City of Carlsbad Street and Sidewalk Policy Committee (February 2003)”. As such, Valley Street is intended to retain its current “design in lieu of” categorization, with improvements only being initiated based upon certain prescribed triggers. One of these “triggers” is drainage problems.  Valley Street and McCauley Lane (Site 8) Ponding and inadequate drainage has been observed at two locations near the intersection of Valley Street and McCauley Lane. The first is the low point in the curb return at the north end of the cross gutter. The second is the low point in the berm on the west side of Valley Street approximately 75’ north of the intersection with McCauley Lane. This portion of Valley Street is also considered an “Alternative Design”, based upon “the City of Carlsbad Street and Sidewalk Policy Committee (February 2003)”. As such, Valley Street is intended to retain its current “design in lieu of” categorization, with improvements only being initiated based upon certain prescribed triggers. One of these “triggers” is drainage problems.  Highland Drive (Site 9) There is an existing inlet approximately half way between Magnolia Avenue and Tamarack Avenue on Highland Drive. The inlet currently discharges to the adjacent property to the west. The intent is to capture the runoff at that same location, but instead of discharging on the property to the west, pipe the runoff along Highland Drive toward Magnolia Avenue. The system will discharge through the curb on Magnolia Avenue. Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 2  Linda Lane (Site 10) During wet weather conditions, ponding has been observed within the northwest and southeast cul-de-sac ends of Linda Lane. This is created by extensive sections of excessively flat gradient within the gutter. Additionally, groundwater has been observed seeping up through the pavement near an existing AT&T utility trench that traverses the northwest cul-de-sac. It is speculated that the recent installation of the AT&T trench has provided a hydraulic connection to an older utility trench that was installed previously within Linda Lane. The influx of groundwater within the cul-de- sac area, along with wet weather conditions creates an almost constant occurrence of standing water within the gutter. When ponding groundwater reaches the relatively steeper eastern leg of Linda Lane, it has been observed to flow at a rate producing a “gutter full” condition. Figure 1-1 Vicinity Map Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 3 1.3 Existing Conditions The existing drainage areas are described as follows and can be seen on the map included in APPENDIX B:  3065 Ocean Street (Site 6) This area consists of single family homes along the west side of Ocean Street. Runoff currently flows along the fronts of the residences in either a ribbon gutter or along the edge of pavement. Runoff is conveyed to the south and is eventually collected in an existing storm drain system that discharges to the beach.  Valley Street and Buena Vista Way (Site 7) This area consists of both single family residential and agricultural development. Runoff in Buena Vista Way generally flows east to west and runoff in Valley Street generally flows southeast to northwest. The flow is collected in an existing storm drain system located in Buena Vista Way that conveys flow back down Valley Street toward Carlsbad Village Drive (bucking grade).  Valley Street and McCauley Lane (Site 8) This area consists of both single family homes and a church. Runoff in McCauley Lane generally flows east to west and runoff in Valley Street generally flows southeast to northwest. Runoff from Site 8 is conveyed to the same storm drain system as Site 7.  Highland Drive (Site 9) This area consists of single family homes. Runoff currently flows toward an existing inlet on Highland Drive located approximately half way between Magnolia Avenue and Tamarack Avenue. The existing inlet currently discharges to an adjacent lot (APN 205-280-32).  Linda Lane (Site 10) This area consists of single family homes. Runoff on Linda Lane currently flows southwest towards Monroe Street in existing gutters. Runoff is eventually collected in an existing storm drain system on Monroe Street. As mentioned above, groundwater intrusion and standing water have historically been a concern at this location. FEMA has mapped the project sites and surrounding areas as Unshaded “Zone X” (i.e. outside the 500 year floodplain). Refer to APPENDIX A. Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 4 2. Study Objectives The objectives for this study include the following:  Document the location(s) of run-on, run-off for each site.  Develop hydrologic parameters and calculate 2, 10, and 100-year flow rates for existing conditions.  Within the problem areas noted for each site, assess the hydraulic capacity of existing gutters, curb inlets and pipes during the 2, 10, and 100-year storms. Determine if any existing facilities warrant replacement or improvement based upon compliance with City standards or other reasonable engineering judgment.  Alternatively, see if drainage problems at any of the sites could be alleviated through curb replacement or other minor surface improvements.  Serve as a technical basis of design for completion of final improvement plans. 3. Methodology 3.1 Hydrology Existing hydrologic parameters have been developed using the Rational Method procedures according to 2003 County of San Diego Hydrology Manual (SDCHM), as adapted within Volume 1, Chapter 5 of the City of Carlsbad Engineering Standards. Calculations have been performed utilizing these parameters within a standard excel spreadsheet.  Soils information to develop loss rates has been taken from the Natural Resource Conservation Service (NRCS) web soil survey. Refer to the soils map and NRCS descriptions in APPENDIX A.  Precipitation values from the 100-year 6 hour Rainfall Isopluvial map in Appendix B of the SDCHM.  C values were determined from Table 3-1 in the SDHM, in conjunction with impervious area estimates from public domain aerial photographs. A summary of these values can be found within Table 4-1.  For smaller drainage areas, the time of concentration (Tc) has been conservatively assumed to be 5 minutes. For larger drainage areas, the initial time (Ti)was determined based on Table 3-2 in the SDCHM, with additional travel time (Tt) based on a conservative assumption of 5 ft/sec. All calculated values can be found on Table 4-1 Hydrology Summary.  Drainage areas (A) were determined based on available topographic information for each project site. Site inspections were conducted to verify the potential presence of physical drainage features capable of impacting flow paths, but too insignificant to be identified as part of an area-wide aerial topographic survey. Drainage area delineations can be found in APPENDIX B. Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 5 3.2 Hydraulics 3.2.1 Street Capacity The City of Carlsbad Engineering Standards require that an inlet to an underground storm system be provided when enough flow has accumulated within the gutter to cause the depth to approach or exceed the top of curb elevation during the 100 year, 6 hour event. Street capacity was analyzed at various cross sections for the existing conditions at each site using Flowmaster software, which determines flow depth based upon Manning’s equation for uniform channel conditions. Street capacity calculations for each site can be found within APPENDIX C and are summarized in Table 4-2. The calculations were performed for the 100 year event, as well as the 10 year and 2 year. In locations where there is no curb, street capacity is determined based on either the existing berm, or in the case of Ocean Street, finished grade in front of the resident’s garage. 3.2.2 Storm Drain Sizing The City of Carlsbad Engineering Standards requires that public drainage facilities contain the 10 year, 6 hour event “underground”. The proposed storm drain pipes have been sized according to this criterion. The results of the calculations can be found in APPENDIX D. 3.2.3 Inlet Sizing The inlet capacity calculations have been performed based on the City of Carlsbad Engineering Standards (Chapter 5, Section 4). The results of the calculations can be found in APPENDIX D. Inlets should also be sized to capture the 10 year, 6 hour event (at a minimum) without bypass, and while maintaining the maximum permissible flow depth. Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 64. Results 4.1 Hydrology Table 4-1 Hydrology Summary Basin ID Area C Ti Tt Tc 2 Year 10 Year 100 Year P6 I Q2 P6 I Q10 P6 I Q100 6 0.15 0.90 - - 5 1.2 3.16 0.4 1.6 4.22 0.6 2.4 6.32 0.9 7A 1.86 0.85 5 2 7 1.2 2.54 4.0 1.8 3.82 6.0 2.6 5.51 8.7 7B 5.08 0.50 5 2.9 7.9 1.2 2.35 6.0 1.8 3.53 9.0 2.6 5.10 13.0 8 3.17 0.78 5 1.8 6.8 1.2 2.59 6.4 1.8 3.89 9.6 2.6 5.62 13.9 9A 1.38 0.54 7.9 0.9 8.8 1.2 2.20 1.6 1.8 3.29 2.5 2.6 4.76 3.5 9B 0.45 0.54 7.9 1.5 9.4 1.2 2.10 0.5 0.8 1.40 0.3 1.6 2.81 0.7 9C 0.26 0.77 - - 5 1.2 3.16 0.6 1.8 4.74 0.9 2.6 6.85 1.4 10A 1.37 0.77 - - 5 1.2 3.16 3.3 1.8 4.74 5.0 2.6 6.85 7.2 10B 1.50 0.67 - - 5 1.2 3.16 3.2 1.8 4.74 4.8 2.6 6.85 6.9 10C 2.87 0.77 - - 5 1.2 3.16 7.0 1.8 4.74 10.5 2.6 6.85 15.1 Where: Area: Tributary drainage area in acres Tt: Travel time of concentration in minutes I: Rainfall intensity in inches per hour C: Runoff coefficient Tc: Total time of concentration in minutes Q: Flow rate in cubic feet per second Ti: Initial time of concentration in minutes P6: 6-hour rainfall depth Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 7 4.2 Hydraulics Table 4-2 Street Capacity Summary Section Location 100-Year Event 10-Year Event 2-Year Event 6-1 Ocean Street Yes Yes Yes 7-1 Buena Vista Way Yes Yes Yes 7-2 Valley Street No No No 8-1 McCauley Street Yes Yes Yes 8-2 Valley Street No No No 10-1 Linda Lane Yes Yes Yes 10-2 Linda Lane Yes Yes Yes 10-3 Linda Lane Yes Yes Yes Note: Due to the fact that there is no consistent curb/berm on Highland Drive, street capacity calculations are not warranted. 5. Conclusions and Recommendations The following are summaries of the factors that contribute to the drainage issues at each location:  3065 Ocean Street (Site 6) The observed ponding is a result of a low point in front of the garage for the residence at 3065 Ocean Street. The low point is approximately 1’ upstream of the planter that is located immediately to the south of the garage. Without this isolated low point, the typical street section is adequate to convey the required flow.  Valley Street and Buena Vista Way (Site 7) There are two separate drainage issues at Site 7. The first is a low point on Valley Street that results in ponded water after a rain event. The hydraulic calculations also show substandard conveyance capacity within the street section due to the minimal longitudinal slope (0.3%) and the lack of a pronounced crown. The second is sheet flow crossing Buena Vista Way upstream of Valley Street. The sheet flow condition is a result of the fact that much of Buena Vista Way between Crest Drive and Valley Street has a pronounced crown causing drainage to travel down either side of the road. As Buena Vista Way approaches the intersection with Valley Street, it transitions out of the crowned condition and becomes superelevated. The superelevated condition causes runoff to sheet flow across the road from south to north.  Valley Street and McCauley Lane (Site 8) There are two separate drainage issues at Site 8. The first is a low point in the cross gutter at the intersection with McCauley Lane. The isolated low point causes ponded water after a rain event. The second is a low point in the flowline of the AC berm on the west side of Valley Street approximately 75’ north of the intersection with McCauley Lane. This isolated low point also causes ponded water after a rain event. Both low points are likely due to the fact that the longitudinal slope of Valley Street generally is very flat, and over time, settling has occurred within the asphalt. Without the isolated low points, the typical street section for McCauley Lane is adequate to convey the required flow, but the typical street section for Valley Street is not, due primarily to the extremely flat longitudinal gradient (0.8%). Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 8  Highland Drive (Site 9) The drainage issue at this site is simply the location of the discharge (adjacent property to the west). The City would prefer not to discharge to the adjacent private property. There are no concerns with the hydraulics of the existing pipe or inlet. There is also a low point in the existing street approximately 400’ from the intersection with Magnolia Avenue. The low point can cause several inches of ponding after a rain event.  Linda Lane (Site 10) The primary issue at this site is the minimal longitudinal slope (some portions have a negative slope) in the gutter around the two cul-de-sacs. This causes inadequate conveyance of the 10 and 100 year storm events as well as isolated ponding. This issue is compounded by the frequent presence of groundwater, which also causes algae growth in the gutters. As discussed previously, the recent utility trenching that intersected the existing subdrain is suspected to have allowed the groundwater to seep to the surface with little hydraulic resistance. The project geotechnical engineer attempted to sample the groundwater, but did not encounter any water in their well after two weeks. The presence of non-visible pollutants could impact the feasibility of discharging this water within the City’s MS4 (Municipal Separate Storm Sewer System). The following are recommendations for addressing the drainage issues at each location:  3065 Ocean Street (Site 6) Three conceptual drainage alternatives have been developed for Site 6. A schematic mark-up of the alternatives is included in APPENDIX C: o Alternative #1 - Inlet and Pipe – install an inlet at the low point in front of the garage. Additional storm drain pipe would also be required in order to convey flow to the existing system to the south. o Alternative #2 - Lower the high point – the existing high point at the corner of the planter would be lowered. Some modifications to the planter would be required as well as a step going into the existing gate. This alternative would likely involve pavement replacement. o Alternative #3 - Fill the low point – the existing low point would be raised with a grind and variable AC overlay. The existing utilities to the north of the garage would need to be raised to match finished grade. This alternative would reduce the conveyance capacity compared to the existing condition but not to the extent where performance with City standards would be compromised given the minimal flow rate. This alternative would have very little construction tolerance for plan deviation or for long term grade settlement.  Valley Street and Buena Vista Way (Site 7) A new inlet is recommended at the low point in Valley Street along with a new pipe to connect to the existing system. The inlet will be “Type F” per SDRSD D-7. Curb cuts will be installed in the existing AC berm allowing runoff to enter into proposed concrete ditches located immediately behind the existing curb. The ditches will convey runoff to the proposed inlet. Setting the ditch and inlet behind the existing berm is assumed to help maintain the current character of this Alternative Design Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 9 Street. There is also a small point repair proposed for the existing storm drain in Valley Street. No improvements are proposed on Buena Vista Way.  Valley Street and McCauley Lane (Site 8) On the west side of Valley Street, a new inlet and pipe are recommended. The inlet will be a 5’ Regional Standard Type B inlet and the pipe will be 12” PVC. A new pipe and inlet is also recommended on the east side of Valley Street. The pipe will be 24” PCV and the inlet will be a 14’ Regional Standard Type B-1 inlet. Other proposed improvements include widening both Valley Street and McCauley at the northeast corner of the intersection, new curb and gutter, AC berm transitions, new sidewalk, new pedestrian ramp, and a small Regional Standard retaining wall.  Highland Drive (Site 9) A new pipe and two 24 x 24 Grated Brooks Box inlets are recommended for this site. The pipe system will convey the flow along Highland Drive toward Magnolia Avenue through an 18” RCP. The first inlet will be in the same approximate location as the existing inlet. The second inlet will be located at the low point on the northeast side of the street, approximately 400’ south of the intersection with Magnolia Avenue. The pipe will pick up flow captured by the second inlet and also connect with the existing pipe coming from the inlet at the southeast corner of Highland Drive and Magnolia Avenue. Approaching Magnolia Avenue the 18” RCP downsizes to a 12” RCP. Although downsizing is not typical, it is necessary to maintain cover over the pipe as it approaches the D-25 curb outlet to Magnolia Avenue. The downsize will also cause the system to flow under pressure in the 100-year event, but the HGL will still be well below the existing ground.  Linda Lane (Site 10) The drainage issues at this site cannot be fixed with surface improvements alone without replacing a significant portion of the existing curb and pavement within both cul-de-sacs. A combination of minor surface improvements, pipes, and inlets is recommended. Additional perforated sub-drain pipe should be located at each end of the existing subdrain so that flow can be intercepted prior to entering the AT&T trench. Inlets should also be placed at isolated low spots within the gutters, per the project survey information. Runoff collected in the inlets and sub-drain within the upper cul-de-sac areas will be conveyed in a “tight-line” pipe that will run down the eastern leg of Linda Lane and ultimately connect to the existing system in Monroe Street. The 10-year peak flow rate will be captured by 4 – 24 x 24” Grated Brooks Box inlets located at both the north and south ends of the cul-de-sac and conveyed by a system of pipes ranging from 10”-18”. The 100-year peak flow rate will be conveyed below the top of curb elevation by a combination of pipe and gutter flow. If the project geotechnical engineer believes that elevated groundwater levels also currently exist within the “eastern leg”, then an alternative approach should be considered within this area. This alternative approach might involve use of a perforated sub-drain with periodic installation of small cutoff structures to prevent transport of trench material by rapidly flowing groundwater (aka “piping”). Since no non-visible pollutants have been identified, a diversion of flow to treatment Best Management Practices in order to maintain compliance with the Regional Groundwater Extraction NPDES Permit is not warranted. Carlsbad Northwest Quadrant Improvements Hydrology and Hydraulics Study Valley Street, Ocean Street, Highland Drive, and Linda Lane 10 6. References San Diego County Department of Public Works Flood Control Section. Hydrology Manual (SDCHM). June 2003. San Diego County. Drainage Design Manual (SDCDDM). July 2005 Soil Conservation Service (SCS). Soil Survey San Diego Area, California. December 1973. City of Carlsbad Engineering Standards, Volume 1, Chapter 5, 2008. APPENDIX A - NRCS Soils Information and FEMA Maps MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Units Soil Ratings A A/D B B/D C C/D D Not rated or not available Political Features Cities Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Map Scale: 1:2,500 if printed on A size (8.5" × 11") sheet. The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for accurate map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: UTM Zone 11N NAD83 This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 6, Dec 17, 2007 Date(s) aerial images were photographed: 6/7/2005 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/18/2012 Page 2 of 4 Hydrologic Soil Group Hydrologic Soil Group— Summary by Map Unit — San Diego County Area, California (CA638) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CbC Carlsbad gravelly loamy sand, 5 to 9 percent slopes C 7.8 65.0% MlC Marina loamy coarse sand, 2 to 9 percent slopes B 1.4 11.7% MlE Marina loamy coarse sand, 9 to 30 percent slopes B 2.8 23.3% Totals for Area of Interest 12.0 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/18/2012 Page 3 of 4 Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/18/2012 Page 4 of 4 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Units Soil Ratings A A/D B B/D C C/D D Not rated or not available Political Features Cities Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Map Scale: 1:1,740 if printed on A size (8.5" × 11") sheet. The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for accurate map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: UTM Zone 11N NAD83 This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 6, Dec 17, 2007 Date(s) aerial images were photographed: 6/7/2005 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/7/2012 Page 2 of 4 Hydrologic Soil Group Hydrologic Soil Group— Summary by Map Unit — San Diego County Area, California (CA638) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CgC Chesterton-Urban land complex, 2 to 9 percent slopes D 0.0 0.2% MlC Marina loamy coarse sand, 2 to 9 percent slopes B 0.1 1.6% MlE Marina loamy coarse sand, 9 to 30 percent slopes B 4.2 98.2% Totals for Area of Interest 4.3 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/7/2012 Page 3 of 4 Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/7/2012 Page 4 of 4 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Units Soil Ratings A A/D B B/D C C/D D Not rated or not available Political Features Cities Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Map Scale: 1:1,860 if printed on A size (8.5" × 11") sheet. The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for accurate map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: UTM Zone 11N NAD83 This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 6, Dec 17, 2007 Date(s) aerial images were photographed: 6/7/2005 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/7/2012 Page 2 of 3 Hydrologic Soil Group Hydrologic Soil Group— Summary by Map Unit — San Diego County Area, California (CA638) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI MlC Marina loamy coarse sand, 2 to 9 percent slopes B 7.3 100.0% Totals for Area of Interest 7.3 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group–San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/7/2012 Page 3 of 3 Project Site Project Site Project Site Project Site APPENDIX B – Existing Condition Hydrology Maps APPENDIX C - Existing Condition Street Capacity Calculations Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00800 ft/ft Normal Depth 0.07 ft Discharge 0.40 ft³/s Cross Section Image Cross Section 6-1 - 2-year 6/18/2012 5:46:46 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00800 ft/ft Normal Depth 0.08 ft Discharge 0.60 ft³/s Cross Section Image Cross Section 6-1 - 10-year 6/18/2012 5:43:43 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00800 ft/ft Normal Depth 0.09 ft Discharge 0.90 ft³/s Cross Section Image Cross Section 6-1 - 100-year 6/18/2012 5:38:32 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05800 ft/ft Normal Depth 0.20 ft Discharge 4.00 ft³/s Cross Section Image Cross Section 7-1 - 2-year 9/20/2012 8:20:55 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05800 ft/ft Normal Depth 0.23 ft Discharge 6.00 ft³/s Cross Section Image Cross Section 7-1 - 10-year 9/20/2012 8:22:20 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05800 ft/ft Normal Depth 0.25 ft Discharge 8.70 ft³/s Cross Section Image Cross Section 7-1 - 100-year 9/20/2012 8:22:36 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00300 ft/ft Normal Depth 0.26 ft Discharge 6.00 ft³/s Cross Section Image Cross Section 7-2 - 2-year 9/20/2012 8:24:36 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00300 ft/ft Normal Depth 0.32 ft Discharge 9.00 ft³/s Cross Section Image Cross Section 7-2 - 10-year 9/20/2012 8:25:36 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.00300 ft/ft Normal Depth 0.40 ft Discharge 13.00 ft³/s Cross Section Image Cross Section 7-2 - 100-year 9/20/2012 8:25:54 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05000 ft/ft Normal Depth 0.23 ft Discharge 6.40 ft³/s Cross Section Image Cross Section 8-1 - 2-year 9/20/2012 8:27:44 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05000 ft/ft Normal Depth 0.26 ft Discharge 9.60 ft³/s Cross Section Image Cross Section 8-1 - 10-year 9/20/2012 8:27:16 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.05000 ft/ft Normal Depth 0.29 ft Discharge 13.90 ft³/s Cross Section Image Cross Section 8-1 - 100-year 9/20/2012 8:26:46 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.39 ft Discharge 7.80 ft³/s Cross Section Image Cross Section 8-2 - 2-year 6/18/2012 5:49:32 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.44 ft Discharge 11.70 ft³/s Cross Section Image Cross Section 8-2 - 10-year 6/18/2012 5:46:13 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.50 ft Discharge 16.90 ft³/s Cross Section Image Cross Section 8-2 - 100-year 6/18/2012 5:43:08 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.37 ft Discharge 3.30 ft³/s Cross Section Image Cross Section for Linda 10-1 - 2-Year 5/1/2013 1:22:56 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.46 ft Discharge 5.00 ft³/s Cross Section Image Cross Section for Linda 10-1 - 10-Year 5/1/2013 1:21:44 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.51 ft Discharge 7.20 ft³/s Cross Section Image Cross Section for Linda 10-1 - 100-Year 5/1/2013 1:18:23 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.37 ft Discharge 3.20 ft³/s Cross Section Image Cross Section for Linda 10-2 - 2-Year 5/1/2013 1:25:28 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.43 ft Discharge 4.80 ft³/s Cross Section Image Cross Section for Linda 10-2 - 10-Year 5/1/2013 1:24:46 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.01000 ft/ft Normal Depth 0.49 ft Discharge 6.90 ft³/s Cross Section Image Cross Section for Linda 10-2 - 100-Year 5/1/2013 1:24:09 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.04000 ft/ft Normal Depth 0.32 ft Discharge 7.00 ft³/s Cross Section Image Cross Section for Linda 10-3 - 2-Year 5/1/2013 1:32:16 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.04000 ft/ft Normal Depth 0.36 ft Discharge 10.50 ft³/s Cross Section Image Cross Section for Linda 10-3 - 10-Year 5/1/2013 1:31:21 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.04000 ft/ft Normal Depth 0.40 ft Discharge 15.10 ft³/s Cross Section Image Cross Section for Linda 10-3 - 100-Year 5/1/2013 1:30:36 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Ocean Street APPENDIX D – Proposed Condition Pipe and Inlet Calculations Inlet Capacity Page 1 of 7 Site 7A - Curb Inlet in Sag (Valley Street Flow From North) San Diego County Drainage Design Manual Q = inlet capacity (cfs) h = curb opening height (ft) L = curb opening length (ft) g = gravitational acceleration (ft2/s) do = effective depth of flow at curb face (ft) h = 0.75 ft L = 3.0 ft g 32.2 ft2/s do =1.0 ft Q =12.1 cfs Capacity of one opening Q10 = 6.0 cfs 10-year flow rate at this location Q100 = 8.7 cfs 100-year flow rate at this location Use 3' wide 1' deep Type D ditch with one opening on Type F inlet. (Inlet will completely capture both the 10-year and 100-year event) 2 1 )2(67.0 ogdhLQ Inlet Capacity Page 2 of 7 Site 7B - Curb Inlet in Sag (Valley Street Flow From South) San Diego County Drainage Design Manual Q = inlet capacity (cfs) h = curb opening height (ft) L = curb opening length (ft) g = gravitational acceleration (ft2/s) do = effective depth of flow at curb face (ft) h = 0.75 ft L = 3.0 ft g 32.2 ft2/s do =1.0 ft Q =12.1 cfs Capacity of one opening Q10 = 9.0 cfs 10-year flow rate at this location Q100 = 13.0 cfs 100-year flow rate at this location Use 4' wide 1' deep Type D ditch with one opening on Type F inlet. (Inlet will completely capture the 10-year event, 0.9 cfs will flow in the street during the 100-year event.) 2 1 )2(67.0 ogdhLQ Inlet Capacity Page 3 of 7 Site 8 - Curb Inlet (Valley Street East) Interim Condition - Sump Condition Ultimate Condition - On-Grade Condition City of Carlsbad Engineering Standards Manual City of Carlsbad Engineering Standards Manual Criteria is 2 cfs per lineal foot of opening Q = interception capacity of the curb inlet (cfs) Q100 = 13.9 cfs y = depth of flow approaching the curb inlet (ft) L(min) = 7.0 ft Min for 100-yr a = depth of depression of curb at inlet (ft) LT = length of clear opening of inlet for total interception (ft) y =0.50 ft a = 0.33 ft Q100 = 13.9 cfs LT = 26.1 cfs Length required for full capture of 100-year event County of San Diego Drainage Design Manual equation for partial interception A 13' inlet opening will provide sufficient partial E = curb-opening inlet efficiency interception capacity to capture the peak 10-year L' = Length of clear opening of installed inlet (ft) flow rate in the ultimate condition, while also LT = Length of clear opening for total interception (ft) providing sufficient capacity to capture the peak 100-year flow rate in the interim condition.L'=13 ft actual inlet opening E=0.710785 Q=9.9 cfs partial capture rate Q10 = 9.6 cfs TLyaQ2 3 )(7.0  8.1'11       TL LE Inlet Capacity Page 4 of 7 Site 8 - Curb Inlet on Grade (Valley Street West) City of Carlsbad Engineering Standards Manual Q = interception capacity of the curb inlet (cfs) y = depth of flow approaching the curb inlet (ft) a = depth of depression of curb at inlet (ft) LT = length of clear opening of inlet for total interception (ft) y =0.50 ft a = 0.0 ft LT =4.0 ft Q = 1.0 cfs Use a 4' curb inlet with 6" opening. Q at location of inlet is 1 cfs. TLyaQ2 3 )(7.0  Inlet Capacity Page 5 of 7 Site 9 - Grated Inlet in Sag (Highland Drive, End of Main Line) FHWA HEC-22 and San Diego County Drainage Design Manual Try a 24" x 24" grated inlet Weir Orifice Q = inlet capacity of the grated inlet (cfs)Q = inlet capacity of the grated inlet (cfs) Cw = weir coefficient = 3.0 Co = orifice coefficient = 0.67 Pe = effective grate perimeter (ft) w/ 50% clogging factor Ae = effective grate area (ft2) w/ 50% clogging factor d = flow depth approaching inlet (ft)g = gravitational acceleration (ft2/s) d = flow depth above inlet (ft) Pe =4 ft (4 sides) Cw =3.0 Ae =2 ft2 d = 0.5 ft Co =0.67 g =32.2 ft2/s Q = 4.2 cfs d =0.5 ft Q = 7.6 cfs The weir equation governs (Q = 4.2 cfs). Q100 at location of inlet is 3.5 cfs. Use a 24" x 24" grated inlet. 2 3 dPCQew2 1 )2(gdACQeo Inlet Capacity Page 6 of 7 Site 9 - Grated Inlet in Sag (Highland Drive, Lateral) FHWA HEC-22 and San Diego County Drainage Design Manual Try a 12" x 12" grated inlet Weir Orifice Q = inlet capacity of the grated inlet (cfs)Q = inlet capacity of the grated inlet (cfs) Cw = weir coefficient = 3.0 Co = orifice coefficient = 0.67 Pe = effective grate perimeter (ft) w/ 50% clogging factor Ae = effective grate area (ft2) w/ 50% clogging factor d = flow depth approaching inlet (ft)g = gravitational acceleration (ft2/s) d = flow depth above inlet (ft) Pe =2 ft (4 sides) Cw =3.0 Ae =0.5 ft2 d = 0.5 ft Co =0.67 g =32.2 ft2/s Q = 2.1 cfs d =0.5 ft Q = 1.9 cfs The orifice equation governs (Q = 1.9 cfs). Q100 at location of inlet is 0.7 cfs. Use a 24" x 24" grated inlet for ease of maintenance. 2 3 dPCQew2 1 )2(gdACQeo Inlet Capacity Page 7 of 7 Site 10 - Grated Inlet in Sag (Linda Lane) FHWA HEC-22 and San Diego County Drainage Design Manual Try a 24" x 24" grated inlet Weir Orifice Q = inlet capacity of the grated inlet (cfs)Q = inlet capacity of the grated inlet (cfs) Cw = weir coefficient = 3.0 Co = orifice coefficient = 0.67 Pe = effective grate perimeter (ft) w/ 50% clogging factor Ae = effective grate area (ft2) w/ 50% clogging factor d = flow depth approaching inlet (ft)g = gravitational acceleration (ft2/s) d = flow depth above inlet (ft) Pe =3 ft (3 sides) Cw =3.0 Ae =2 ft2 d = 0.5 ft Co =0.67 g =32.2 ft2/s Q = 3.2 cfs d =0.5 ft Q = 7.6 cfs The weir equation governs (Q = 3.2 cfs). Q100 2.5 cfs to each of the 4 inlets. Use a 24" x 24" grated inlets. 2 3 dPCQew2 1 )2(gdACQeo Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.00400 ft/ft Constructed Depth 1.00 ft Normal Depth 0.96 ft Constructed Top Width 3.00 ft Discharge 8.70 ft³/s Cross Section Image Cross Section Site 7A Ditch (Valley St Flow From North) 9/20/2012 11:11:19 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.00400 ft/ft Constructed Depth 1.00 ft Normal Depth 0.99 ft Constructed Top Width 4.00 ft Discharge 13.00 ft³/s Cross Section Image Cross Section Site 7B Ditch (Valley St Flow From South) 9/20/2012 11:12:13 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.01000 ft/ft Normal Depth 1.57 ft Diameter 2.00 ft Discharge 21.70 ft³/s Cross Section Image Cross Section Site 7 Valley Street Proposed Pipe 9/20/2012 1:30:46 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.01000 ft/ft Normal Depth 1.13 ft Diameter 2.00 ft Discharge 13.90 ft³/s Cross Section Image Cross Section Site 8 Valley Street East Proposed Pipe 9/20/2012 1:30:11 PM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.01000 ft/ft Normal Depth 0.36 ft Diameter 1.00 ft Discharge 1.00 ft³/s Cross Section Image Cross Section Site 8 Valley Street West Proposed Pipe 9/28/2012 9:02:17 AM Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.01000 ft/ft Normal Depth 0.61 ft Diameter 0.83 ft Discharge 2.50 ft³/s Cross Section Image Cross Section for Site 10A - Linda lane 10" - 10 year 9/5/2013 4:00:55 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page The 10" pipe can successfully convey the 10yr event. Based on the street capacity (Appendix C), the 100yr event is still conveyed below the top of curb per city design standards. Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.02720 ft/ft Normal Depth 0.74 ft Diameter 1.00 ft Discharge 6.90 ft³/s Cross Section Image Cross Section for Site 10A - Linda lane 12" - 100 year 9/5/2013 3:58:23 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.01000 ft/ft Normal Depth 0.59 ft Diameter 0.83 ft Discharge 2.40 ft³/s Cross Section Image Cross Section for Site 10B - Linda lane 10" - 10 year 9/5/2013 4:02:08 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page The 10" pipe can successfully convey the 10yr event. Based on the street capacity (Appendix C), the 100yr event is still conveyed below the top of curb per city design standards. Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.03310 ft/ft Normal Depth 0.71 ft Diameter 1.00 ft Discharge 7.20 ft³/s Cross Section Image Cross Section for Site 10B - Linda Lane 12" - 100 year 9/5/2013 3:50:35 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.013 Channel Slope 0.04500 ft/ft Normal Depth 0.91 ft Diameter 1.50 ft Discharge 15.10 ft³/s Cross Section Image Cross Section for Site 10C - Linda Lane 18" - 100 year 9/5/2013 3:46:13 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1of1Page 1 2 3 4 5 6 Outfall Hydraflow Storm Sewers Extension for AutoCAD® Civil 3D® 2009 Plan Project File: Highland.stm Number of lines: 6 Date: 09-05-2013 Hydraflow Storm Sewers Extension v6.066 Storm Sewer Summary Report Page 1 Line Line ID Flow Line Line Line Invert Invert Line HGL HGL Minor HGL Dns Junction No.rate size shape length EL Dn EL Up slope down up loss Junct line Type (cfs)(in)(ft)(ft)(ft)(%)(ft)(ft)(ft)(ft)No. 1 5.60 12 Cir 60.000 162.28 162.46 0.300 163.48*164.96*n/a 165.02 i End Manhole 2 5.60 18 Cir 18.000 162.47 162.52 0.278 165.02*165.07*0.12 165.18 1 Manhole 3 4.20 18 Cir 265.000 162.53 163.33 0.302 165.18*165.61*0.09 165.70 2 Manhole 4 3.50 18 Cir 238.000 163.34 164.05 0.298 165.70*165.96*0.05 166.01 3 Manhole 5 3.50 18 Cir 15.000 164.06 164.13 0.467 166.01*166.02*0.06 166.08 4 Manhole 6 0.70 8 Cir 15.000 164.71 165.01 2.000 165.70*165.75*0.06 165.81 3 Manhole Project File: Highland.stm Number of lines: 6 Run Date: 09-05-2013 NOTES:  Return period = 100 Yrs.  ; *Surcharged (HGL above crown).  ; i ­ Inlet control. Hydraflow Storm Sewers Extension v6.066 Hydraulic Grade Line Computations Page 1 Line Size Q Downstream Len Upstream Check JL Minor coeff loss Invert HGL Depth Area Vel Vel EGL Sf Invert HGL Depth Area Vel Vel EGL Sf Ave Enrgy elev elev head elev elev elev head elev Sf loss (in)(cfs)(ft)(ft)(ft)(sqft)(ft/s)(ft)(ft)(%)(ft)(ft)(ft)(ft)(sqft)(ft/s)(ft)(ft)(%)(%)(ft)(K)(ft) 1 12 5.60 162.28 163.48 1.00 0.79 7.13 0.79 164.27 n/a 60.000 162.46 164.96 1.00 0.79 7.13 0.79 165.75i n/a n/a 0.694 0.75 n/a 2 18 5.60 162.47 165.02 1.50 1.77 3.17 0.16 165.17 0.285 18.000 162.52 165.07 1.50 1.77 3.17 0.16 165.22 0.284 0.284 0.051 0.75 0.12 3 18 4.20 162.53 165.18 1.50 1.77 2.38 0.09 165.27 0.160 265.000163.33 165.61 1.50 1.77 2.38 0.09 165.70 0.160 0.160 0.424 1.00 0.09 4 18 3.50 163.34 165.70 1.50 1.77 1.98 0.06 165.76 0.111 238.000164.05 165.96 1.50 1.77 1.98 0.06 166.02 0.111 0.111 0.264 0.75 0.05 5 18 3.50 164.06 166.01 1.50 1.77 1.98 0.06 166.07 0.111 15.000 164.13 166.02 1.50 1.77 1.98 0.06 166.08 0.111 0.111 0.017 1.00 0.06 6 8 0.70 164.71 165.70 0.67 0.35 2.01 0.06 165.76 0.336 15.000 165.01 165.75 0.67 0.35 2.01 0.06 165.81 0.336 0.336 0.050 1.00 0.06 Project File: Highland.stm Number of lines: 6 Run Date: 09-05-2013   ;  c  =  c ir  e  =  e llip   b  =  b o x Hydraflow Storm Sewers Extension v6.066 Storm Sewer Tabulation Page 1 Station Len Drng Area Rnoff Area x C Tc Rain Total Cap Vel Pipe Invert Elev HGL Elev Grnd / Rim Elev Line ID coeff (I)flow full Line To Incr Total Incr Total Inlet Syst Size Slope Dn Up Dn Up Dn Up Line (ft)(ac)(ac)(C)(min)(min)(in/hr)(cfs)(cfs)(ft/s)(in)(%)(ft)(ft)(ft)(ft)(ft)(ft) 1 End 60.000 0.00 0.00 0.00 0.00 0.00 0.0 4.1 0.0 5.60 1.95 7.13 12 0.30 162.28 162.46 163.48 164.96 163.40 169.30 2 1 18.000 0.00 0.00 0.00 0.00 0.00 0.0 4.0 0.0 5.60 5.53 3.17 18 0.28 162.47 162.52 165.02 165.07 169.30 170.11 3 2 265.000 0.00 0.00 0.00 0.00 0.00 0.0 2.1 0.0 4.20 5.77 2.38 18 0.30 162.53 163.33 165.18 165.61 170.11 170.37 4 3 238.000 0.00 0.00 0.00 0.00 0.00 0.0 0.1 0.0 3.50 5.74 1.98 18 0.30 163.34 164.05 165.70 165.96 170.37 167.56 5 4 15.000 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 3.50 7.17 1.98 18 0.47 164.06 164.13 166.01 166.02 167.56 166.88 6 3 15.000 0.00 0.00 0.00 0.00 0.00 0.0 0.0 0.0 0.70 1.71 2.01 8 2.00 164.71 165.01 165.70 165.75 170.37 169.30 Project File: Highland.stm Number of lines: 6 Run Date: 09-05-2013 NOTES: Intensity = 127.16 / (Inlet time + 17.80) ^ 0.82;  R e tu rn  p e rio d  =   100 Yrs.   ;  c  =  c ir  e  =  e llip   b  =  b o x Hydraflow Storm Sewers Extension v6.066