Non-native pepper trees along western boundary of site, facing north (05.25.2021). Tree on left is offsite.
Scattered trees in the riparian area, facing south
(05.25.2021).
Burrowing owl observed onsite on May 30, 2018. The owl was not observed during subsequent surveys in 2018. No owls or owl sign were observed during surveys in 2019 and 2021.
Burrowing owl burrow in 2018. This burrow was not occupied during surveys in 2019 and 2021.
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Location of 2018 burrow in 2021 after agricultural fields were mowed, facing south (11.08.2021). There was no
evidence of occupation before or after mowing.
Potentially suitable burrow with no signs of occupation, after agricultural fields mowed, southeast area of site facing east (11.08.2021).
Potentially suitable habitat for burrowing owl and potential burrow locations were thoroughly searched and no evidence of occupation was found in 2019 and 2021.
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APPENDIX E: CNDDB FORMS
CNDDB forms for 20 21 observations are provided below. The forms were submitted to CDFW online. The CNDDB only tracks nesting for Cooper’s hawk and nesting was not observed, so a CNDDB form for this species is not required. The CNDDB does not track Nuttall’s woodpecker or wrentit, so CNDDB forms for these species are not required.
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APPENDIX F: RIVERSIDE COUNTY DOCUMENTATION
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Certification
Certification: I hereby certify that t he statements furnished above and in the attac hed exhibits present the d ata and information required for thi s biological evaluation, and that th e facts, statements, and information presented are true and c orrect to the b est of my k nowledge and belief.
DATE: March 18, 2022 SIGNED:
Leslie Irish, Principal, L&L Environmental, Inc.
909-335-9897
1) Fieldwork Performed By: 2) Fieldwork Performed By:
Guy Bruyea John Konecny
Name Name
3) Fieldwork Performed By: 4) Fieldwork Performed By:
Name Name
5) Fieldwork Performed By: 6) Fieldwork Performed By:
Name Name
Check here if adding any additional names / signatures below or on other side of page.
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BIOLOGICAL REPORT SUMMARY SHEET
Applicant Name: Richland Communities
Assessor’s Parcel Number(s): 360-300-002, -003, -004, -005, -006, -009, 360-350-001 Section, Township and Range: Sections 15 and 16, Township 6 South, Range 3 West Building and Safety Log Number: ____________________________________________ Case Number: TR 31194 Lot/Parcel _________ EA Number _________
MARK ITEM(S)
SURVEYED FOR
SPECIES or ENVIRONMENTAL ISSUE of
CONCERN
(Mark Yes, No, or N/A
regarding species findings on
the referenced site)
Yes No n/a
Arroyo Southwestern Toad X
X Blue-line Stream(s) X
X Burrowing Owl X (2018) X (2021)
Coachella Valley Fringed-toed Lizard X
X Coastal California Gnatcatcher X
X Coastal Sage Scrub X
Delhi Sands Flower-loving Fly X
Desert Pupfish X
Desert Slender Salamander X
Desert Tortoise X
Flat-tailed Horned Lizard X
X Least Bell’s Vireo (habitat) X
X Oak Woodlands X
X Quino Checkerspot Butterfly (2004 survey) X
X Riverside Fairy Shrimp (habitat) X
X Santa Ana River Woolystar X
San Bernardino Kangaroo Rat X
X Slender-horned Spineflower X
Stephens’ Kangaroo Rat X
X Vernal Pools X
X Wetlands X
X Long-spined spineflower X (2017) X (2021)
X Southern California black walnut X
X Coast Horned Lizard (previous survey) X
X Orange-throated Whiptail (previous survey) X
X Coastal (Western) Whiptail (previous survey) X
X Cooper’s Hawk X
X Northern Harrier (previous survey) X
X White-tailed Kite (previous survey) X
X California Horned Lark X
X Great Egret (previous survey) X
X Great Blue Heron (previous survey) X
X Lawrence’s Goldfinch (previous survey) X
X Loggerhead Shrike (previous survey) X
X California Thrasher (previous survey) X
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MARK ITEM(S)
SURVEYED FOR
SPECIES or ENVIRONMENTAL ISSUE of
CONCERN
(Mark Yes, No, or N/A
regarding species findings on
the referenced site)
Yes No n/a
X Southern California Rufous-crowned Sparrow
(previous survey) X
X Bell’s Sage Sparrow (previous survey) X
X Nuttall’s Woodpecker X
X Wrentit X
X Costa’s Hummingbird (previous survey) X
X Rufous Hummingbird (previous survey) X
X San Diego Black-tailed Jackrabbit X
Species of concern sh all be any uniq ue, rare, endangered, or threate ned species. It shall includ e species used to delineate wetlands and riparian corridors. It shall also include any hosts , p erching, or food pla nts used by any animals listed as rare, enda ngered, threatened, or candidate sp ecies by either state, or federa l regulations, or for Riverside County as listed by the California Department of Fish and Wildlife Natural Diversity Data Base (CNDDB).
I declar e under penalty of perjury that the in formation provided on this summary sheet is in accordance with the information provided in the biological report or habitat assessment.
L & L Environmental, Inc. March 18, 2022
Signature and Company Name Date
___________________________________________
10(a) Permit Number (if applicable) Permit Expiration Date
County Use Only
Received By: _________________________________________ Date: ____________________ PD-B# ______________________________________________
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Attachment E-4
LEVEL OF SIGNIFICANCE CHECKLIST
For Biological Resources
Case Number: TR 31194 Lot/Parcel No. _____________ EA Number _________ Assessor's Parcel Number(s): 360-300-002, -003, -004, -005, -006, -009, 360-350-001 Date: March 18, 2022
Biological Resources: (Check the level of impact that applies to the following questions.)
Potentially Less than Significant Less than No
Significant Impact with Mitigation Significant Impact
Impact Incorporated Impact
a) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Conservation Community Plan, or other approved local, regional, or state conservation plan?
b) Have a substantial adverse eff ect, either directly or thr ough hab itat mod ifications, o n any endangered, or threatened species, as listed in Tit le 14 o f the Californ ia Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12)?
c) Have a substanti al adverse effec t, either dir ectly o r th rough h abitat modifications, on any species identified as a candida te, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Depart ment of Fish and Wildlife, or U. S. Wildlife Service?
d) Interfere substantially with the movement of a ny native resident or migratory fish or wildlife species, or with established nati ve resident migr atory w ildlife corridors, or impede the use o f native wildlife nursery sites?
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LEVEL OF SIGNIFICANCE CHECKLIST
For Biological Resources
e) Have a substantial adverse effect o n any ripa rian habi tat, or other sensitive n atural community identifi ed i n l ocal o r regional plans, policies, regu lations, or by the Californ ia Department of Fish and Wildlife, or the U.S. Fish and Wildlife Service?
f) Have a substantial adverse effect on federally protected wetlands, as defined by Section 404 of the Clean Water Act (including, but not limite d to, marsh, vernal pools, coastal, etc.) through direct removal, filling, hydrological interruption)?
g) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
Findings of Fact:
The site is located within the area covered by the MSHCP but is not within the Criteria Area.
There is one area of PQP Conserved Lands approximately 0.68 miles north-northeast of the site (Ringing Rock Archaeological Site). Other than the Ringing Rock Site, t here are no other PQP or MSHCP Conserved Lands within a mile of the site. The site is not within or near any MSHCP Core Areas or Linkages.
There is one sensitive vegetation community present, arroyo willow thicket.
No state or federall y listed plants were observe d. Two speci al status plant species wer e observed, long-spined spineflower and southern California black walnut.
There is one immature coast live oak and other native and non-native trees present.
Coastal California gnatcatcher present and n esting o n the site. White -tailed kite o bserved during previous surveys, but no nesting detected.
No vernal pools or ponding areas and no fairy shrimp habitat.
Riparian birds ( least Bell's vi reo, southwestern willow flycatcher , western yellow-billed cuckoo) considered absent.
Special status wildlife species detected: orange-throated whiptail , coastal (western) whi ptail, coast horned lizard, Cooper’s hawk, southern California rufous-crowned sparrow, great egret, great blue heron (fly over), Bell’s sage sparrow , burrowing owl, Costa’s hummingbird, wrentit, northern harrie r, Nuttall’s woodpeck er, California horned lar k, loggerhead shrike , rufous hummingbird, Lawrence’s goldfinch, California thrasher, and San Diego black-tailed jackrabbit.
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One (1) adult burrowing owl and an occupied burrow observed in 2018. No owls or owl sign observed in 2019 or 2021.
There is habitat suitable for nesting birds (including raptors) within and adjacent to the site.
The site is not within or adjacent to a wildlife corridor.
A mapped blue -line stream is present and includes MSHCP riparian/riverine habitat as well as state waters/wetlands and federal waters. Regulatory permitting and a DBESP will be required.
Proposed Mitigation:
Preconstruction surveys for burrowing owl.
Preconstruction surveys for nesting birds during nesting season.
Avoidance of riparian habitat and offsite compensation for impacts.
Monitoring Recommended:
Monitoring of ac tive coastal California gnatcatcher nest sites during Project activities recommended.
Monitoring of Project activities that disturb vegetation or soil in an d adjacent to the Avoidance/Compatible Use Area is recommended.
Source: CGP Fig. VI.36-VI.40
Revised October 1999
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APPENDIX G: SITE PLAN
C:\Users\hillb\Documents\L&L\RLCC-03-187, Menifee Meadows\Jurisdictional Delineation\RLCC-03-R187.JD4.doc
Celebrating 20+ Years of Service to Southern CA and the Gre at Basin, WBE Certified (Caltrans, CPUC, WBENC) Mailing Address: 700 East Redlands Blvd, Suite U, PMB#351, Redlands CA 92373 Delivery Address: 721 Nevada Street, Suite 307, Redlands, CA 92373 Webpage: llenviroinc.com | Phone: 909-335-9897 | FAX: 909-335-9893
UPDATED JURISDICTIONAL DELINEATION FOR TR 31194,
GOLDEN MEADOWS, CITY OF MENIFEE, CALIFORNIA
±204.65-Acre Property, ±4.68 Acres Offsite, ±209.33 Acres Surveyed
APNs 360-300-002, -003, -004, -005, -006, -009, 360-350-001, and portions of offsite 360-180-009, 360-300-001, -008, 360-350-019, -022, -023, -024, 360-360-009, -010, -011, and 360-380-004, Tract 31194, Township 6 South, Range 3 West, Sections 15 and 16, USGS Romoland, 7.5’ Topographic Quadrangle
Prepared For:
Brian Hardy
Richland Communities
3161 Michelson Drive, Suite 425
Irvine, CA 92612
949-261-7010
Prepared By:
Leslie Irish, Principal
Guy Bruyea, Biological Investigator
Carla Wakeman, Senior Biologist
Jeffrey Sonnentag, Technical Editor
[email protected]
[email protected]
[email protected]
[email protected]
Report Summary:
The jurisdictional areas identified on the property include 18,814 sq. ft. (0. 43 acre) of ephemeral unvegetated CDFW state waters/streambed (which is also MSHCP Riverine habitat) and 40,451 sq. ft. (0.93 acres) of CDFW state wetland (which is also MSHCP Riparian habitat). Construction of the proposed project will impact 9,541 sq. ft. (0. 22 acre) of CDFW state water/streambed (which is also MSHCP Riverine h abitat) and 5,702 sq. ft. (0.13 acre) of CDFW state wetland ( which is also MSHCP Riparian habitat). The survey also identified 4,397 sq. ft. (0.10 acre) of USACE Waters of the U.S., none of which is USACE federal wetland. The development plan indicate s impacts to 1,301 sq. ft. (0.03 acre) of USACE W aters of the U.S. Remaining jurisdictional areas on the site will be incorporated into a Compatible Use Area.
Surveys Conducted By: Leslie Irish
Surveys Conducted On: February 7, 2018, May 4, 2019, May 21 and June 5, 2021 Report Date: March 2022
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TABLE OF CONTENTS
MANAGEMENT SUMMARY ................................ ................................ ................................ ......iv
1.0) INTRODUCTION ................................ ................................ ................................ ................ 1
1.1) Location................................ ................................ ................................ ........................... 1
1.2) Proposed Project Description ................................ ................................ .......................... 2
1.3) Project Setting ................................ ................................ ................................ ................. 2 Figure 1. Project Vicinity Map ................................ ................................ .............................. 3 Figure 2. Project Location Map ................................ ................................ ........................... 4 Figure 3. Aerial Photograph ................................ ................................ ................................ 5
1.4) Soils and Topography ................................ ................................ ................................ ...... 6 Figure 4. Soils Map ................................ ................................ ................................ ............. 7
2.0) REGULATORY ENVIRONMENT ................................ ................................ ........................ 8
2.1) Jurisdictional Determination of Wetlands, “Waters of the U.S.\ ................................ ........ 8
2.1.1) Federal Clean Water Act, Section 404 ................................ ................................ ...... 8
2.1.2) Federal Clean Water Act, Section 401 ................................ ................................ ...... 9
2.1.3) Evaluation Criteria ................................ ................................ ................................ ..... 9
2.1.4) Federal Clean Water Act, Section 401 ................................ ................................ .....15
2.1.5) California Fish and Game Code, Section 1600 ................................ ........................15
2.2) Western Riverside County Multiple Species Habitat Conservation Plan .........................16
3.0) METHODS ................................ ................................ ................................ .........................18
3.1) Literature Review ................................ ................................ ................................ ...........18
3.2) Jurisdictional Delineation Survey Methods ................................ ................................ .....18 Table 1. Summary of Wetlands Vegetation Criteria ................................ ............................19
3.3) MSHCP Riparian/Riverine and Vernal Pools ................................ ................................ ..19
4.0) RESULTS ................................ ................................ ................................ ..........................20
4.1) Literature Review Results ................................ ................................ ............................... 20
4.2) Vegetation Communities ................................ ................................ ................................ 20
4.2.1) California Buckwheat Scrub ................................ ................................ .....................21
4.2.2) Chamise Chaparral ................................ ................................ ................................ ..21
4.2.3) Arroyo Willow Thickets and Mulefat Thickets ................................ ...........................21
4.2.4) Agriculture and Disturbed/Ruderal ................................ ................................ ...........22 Figure 5. Habitat Map ................................ ................................ ................................ ........23
4.3) State and Federal Jurisdictional Areas ................................ ................................ ...........24 Figure 6. Connection to Pacific Ocean ................................ ................................ ...............25 Figure 7. Jurisdictional Areas Map ................................ ................................ .....................28
4.4) MSHCP Riparian/Riverine and Vernal Pool Habitat ................................ ........................29
5.0) AVOIDANCE MINIMIZATION AND MITIGATION STRATEGY ................................ .........30
5.1) Evaluated Alternatives ................................ ................................ ................................ ....30
5.2) Least Environmentally Damaging Practical Alternative ................................ ...................31
6.0) CONCLUSIONS ................................ ................................ ................................ ................32 Figure 8. Water Resources with Development ................................ ................................ ...33
7.0) REFERENCES ................................ ................................ ................................ ..................34 APPENDIX A ................................ ................................ ................................ ............................36 Updated Jurisdictional Delineation
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Table 2. Summary of Wetlands Criteria and Jurisdiction ................................ ....................37 Table 3. Summary of Impacts ................................ ................................ ............................38 Table 4. Areas to be Incorporated into Compatible Use Area ................................ .............38 Figure 9. Photograph Locations Along Features ................................ ................................ 39 Table 5. Photographs of Features ................................ ................................ ......................40 APPENDIX B ................................ ................................ ................................ ............................46 Site Photographs ................................ ................................ ................................ .................46 2018 Jurisdictional Area Photographs ................................ ................................ ...................49 Additional Photos of Feature 1b................................ ................................ .............................51 APPENDIX C ................................ ................................ ................................ ............................52 List of Plant and Wildlife Species ................................ ................................ ...........................52 APPENDIX D ................................ ................................ ................................ ............................60 Certification ................................ ................................ ................................ ...........................60 Biological Report Summary Sheet ................................ ................................ .........................61 Level of Significance Checklist ................................ ................................ .............................. 63
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MANAGEMENT SUMMARY
L&L Environmental, Inc. conducted a reconnaissance survey and de sktop analysis of Richland Communities ±20 9.33-acre project (and associated offsite improvement areas) in the City of Menifee, California. The purpose of this w ork effort was to update and verify a jurisdictional delineation conducted on the subject property by L&L in 2011 and 2019. A recent biological assessment (L&L 2021) addressed other biological resources on the proj ect site and relevant information from that report is included herein.
The purpose of a (prelim inary) jurisdictional delineation is to quantify the portion of a property that is subject t o the jurisdiction of the U. S. Army Corps of Engineers (USACE), the California Department of Fish and Wildli fe (CDFW), and the Regional Water Quality Control Board (RWQCB). A jurisdictional determination is perform ed to map the wetlands and non -wetland waters that may be subject to regulation by the state or federal agen cies, and that may require permits prior to disturba nce/construction. All jurisdictional deline ations are considered preliminary until verified and accepted by the agencies.
Land use vari es within and adjacent to the survey area and includes anthropogenic disturbances such as rural residential a reas, active and fallow agricultural areas, unimproved roads, power line easements, off-road vehicle activity, debris piles, and windblown debris. Two unimproved roads are present on the property.
A mapped blueli ne stream trending from south to north is present within the central portion of the site as well as various other jurisdictional features. No verna l pools or other areas of potential habitat for fairy shrimp are present on the site.
The jurisdictional areas identified on the property include 18,814 sq. ft. (0.43 acre) of ephemeral unvegetated CDFW state waters/streambed (which is also MSHCP Riverine habitat) and 40,451 sq. ft. ( 0.93 acres) of CDFW state wetland (which is also MSHCP Riparian habitat).
Construction of the propo sed project will impact 9,541 sq. ft. (0. 22 acre) of CDFW state water/streambed (which is also MSHCP Riverine habitat) and 5,702 sq. ft. (0.13 acre) of CDFW state wetland (which is also MSHCP Riparian habitat).
The survey also identified 4,397 sq. ft. (0.10 acre) of USACE Waters of th e U.S. (WoUS), none of which is USACE federa l wetland. The development plan indicates impa cts to 1,301 sq. ft. (0.03 acre) of WoUS.
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Per conversation with the agencies, the project proposes to incorpora te 9,273 sq. ft. (0.21 acre) of state streambed and 34,749 sq. ft. (0. 80 acre) of state wetland , which is also MSHCP Riparian/Riverine habitat, and includes 3,096 sq. ft. (0. 07 acre) of Wo US into the onsite Compatible Use Area.
Permits/agreements and a Determination of Biological Equivalence or Superior Preservation (DBESP) accord ing to the Weste rn Riverside County MSHCP will be required befo re project-related impacts occur.
This document has been prepared to assist in planning and to accompany permit applications or agreements under federal or state law.
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1.0) INTRODUCTION
The following report was prepared by L&L Environmental, Inc. (L&L) for Richland Communities.
It describes the results of a 2011 jurisdictional delineation conducted on a proposed development located on lands within the Cit y of Menifee as well as 2018/2019 and 2021 reconnaissance surveys and desktop analyses that were undertaken to update and verify the results. This report was prepared to accom pany notifications or applications to the U. S. Army Corps of Engineers (USACE), Regional Water Quality Control Board (RWQCB), and California Department of Fish and Wildlife (CDFW) for permits or agreements under applicable federal and state laws. The project site consists of APNs 360 -300-002, -003, -004, -005, -006, -009, and 360-350-001 (totaling ±204.65 acres) and portions of offsite APNs 360 -180-009, 360-300-001, -008, 360-350-019, -022, -023, -24, 360-360-009, -010, -011 and 360-380-004 (totaling ±4.68 acres) where improvements are planned.
Our assessment consisted of (1) a review of the jurisdi ctional delineation conducted by L&L in 2011 (L&L 2012 ) and 2018/201 9 (L&L 2019) and other a vailable information regarding the drainages, and (2) field reconnaissance surveys and desktop analyses, intended to verify and update information in the previous jurisdictional delineations.
1.1) Location
The site is loc ated in the City of Meni fee, in Paloma Valley west of Interstate Hig hway 215 (I-215), south of Newport Road, and east of Murrieta Road (Figure 1). The site is loca ted between Wickerd Road to the south and Garbani Road to the north. The project site is si tuated in Sec tions 15 an d 16, Township 6 South, Range 3 West, within the USGS Romoland 7.5’ series quadrangle map (Figure 2).
The site is generally bounded as follo ws: to the west by agricultural lands, Evans Road (unimproved), rural residential units and a school ; to the eas t by a mixture of disturbed and relatively undis turbed vacant land , Sherman Road (unimproved), and a Frontier Communications complex beyond; to the north by a mixture of disturbed and relatively undisturbed vacant lands, rural r esidential areas, Garbani Road (unimproved) and residential developments; and to t he south by Wickerd Road (unimproved), rural residential areas and a mix of disturbed and relatively undisturbed lands.
In addition to the main site, offsite improvements areas are included in the project. These are comprised of three separate area s: 1) a 0.5 mile section of Wickerd Road between the Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 2 L&L
southeast corner of the main site east to H aun Road ; 2) an are a south of the south-central portion of the main site boundary roughly located between the intersection of Wickerd Road and Bradley Road west to an area just west of Krubsack Road, and 3) an area near the northwest portion of the main si te, including Daniel Road to approximately Evans Road to the west w ith a small area north of and along the northwestern site boundary.
1.2) Proposed Project Description
The Project is identified as Golden Meadows (formerly known as Menifee Assemblage), Tract No. 3119 4, and con sists of construction of 572 single-family residential l ots and associated roads and infrastructure (Figure 3). The Project will be con structed in four (4) phases. Offsite impacts incl ude improvements to existing roads and installation of flood c ontrol structur es.
Approximately 32.3 acres in the northeastern portion of the will be designated as a natural open space area. An En vironmental Impa ct Rep ort for the Project was publis hed in 2006 (T& B 2006).
The property also inc ludes an Eastern M unicipal Wat er District (EM WD) tank site. The proposed tank site includes two large water tanks and an access road. The tanks will serve multiple developments, including Golden Mea dows. The tank site is located within the tract boundary, but it is not within the proposed Project boundary and is not a part of the Project.
1.3) Project Setting
Much of the subject property has been disturbed in association with historic and current dryland farming and sheep grazing. As a result, these areas do not support native habitat communities.
In the historically le ss disturbed areas of the property, remnants of California buckwheat scrub and chamise chaparral vegetation is present.
A shal low drainage feature a nd mapped blue -line stream is present trending from the southwest/central to the northwest portion of the site. Much of this area has been impacted by agricultural activities and invasi ve plants, but s everal woody r iparian species ar e present in association with this feature. In the offsite impact area, t wo small drainage features cross Wickerd Road, an exis ting n arrow dirt road that accesses the site from the east . These two drainages have been impacted by road ma intenance, invasive plants, and adjacent agricultural activities. The easternmost drainage includes limited riparian vegetation.
Land uses adjac ent to the survey area include rural residential, active and fallow a gricultural, large animal husbandry, unimproved roads, powerline easements, off-road vehicle activity, Updated Jurisdictional Delineation
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Figure 1
Project Vicinity Map
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
INVESTIGATIONS AND MONITORING
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Project Area
Updated Jurisdictional Delineation
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Figure 2
Project Location Map
(USGS Romoland 1979 quadrangle,
Sections 15 & 16, Township 6 South, Range 3 West)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
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March 2022
Project Area
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TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 5 L&L
Figure 3
Aerial Photograph
(Photo obtained from Google Earth, February 2018)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
INVESTIGATIONS AND MONITORING
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March 2022
Haun Road
Evans Road Garbani Road
Wickerd Road
Updated Jurisdictional Delineation
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storage, and debris piles. Two unimproved roads are present on the property. One is located along the northern and eastern portion of the property whe re agr icultural areas meet less disturbed sage scrub areas. This unimproved road begins at the eastern terminus of Daniel Road and exits at the south eastern corner of the site near the in tersection of Evans Road and Ascot Way. Krubsack Road (unimproved) trends north to south through previously c ultivated agricultural fields within the roughly west -central portion of the property and connects with Wickerd Road to the south and Daniel Road to the north.
1.4) Soils and Topography
Soils on the Project site were mapped as Wyman loam (WyC2), Vallecitos loam ( VeC2), Porterville clay (PsC ), Yokohl loam (Y bC and YbE3), Cajalco fine sandy loam (CaC2 and CaD2), Cajalco rocky fine sandy loam (CbF2), Honcut sandy loam (HnC and HnD2), Las Posas loam (LaD2), and Las Posas rocky loam (LkD2 and LkF3) (NRCS 2021) (Figure 4).
The most common soils mapped for the su bject property are Wyman loam on the c entral and western portion of the site (in agricultural areas) a nd Las Posas rocky loams on vegetated hillsides within the northern and eastern portions of the site. Clay soils are relatively uncommon on th e site, but Porterville c lay is mapped as present near the southeastern portion of the property. Soils observed onsite range from mostly sandy-loamy within the agricultural areas to rocky l oamy on the vegetated hillsides. Cryptobiotic c rusts are present, but only w ithin less disturbed portions of the site.
Topographically, much of the site is relatively flat and contains open l and with low-relief rocky outcrops. Gently to st eeply sloping h ills and ridgelines are pres ent within t he north eastern portion of the property. The site has a combined maximum vertical relief of roughly 220 feet (67 meters) between the highest and lowest points on the property, with elevation ranging f rom approximately 1,500 to 1,720 feet (457 to 524 meters) above mean sea level (AMSL).
Surrounding topographic features in the project vicinity include gently to steeply sloping hills and ridgelines interspersed with lower-lying relatively flat areas. Although most surrounding areas of the Paloma Valley are primarily flat, significant topograp hic features are present northwest and southwest of the property at eleva tions of approximately 1,760 to 1,820 feet AMSL. Bell Mountain, a significant topographic feature located approximately two ( 2) miles eas t of the subject property, lies at 1,848 feet AMSL.
Updated Jurisdictional Delineation
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CaC2 = Cajalco fine sandy loam, 2-8% slope, eroded
CaD2 = Cajalco fine sandy loam, 8-15% slope, eroded
CbD2 = Cajalco rocky fine sandy loam, 5-15% slope, eroded CbF2 = Cajalco rocky fine sandy loam, 15-50% slope, eroded CkD2 = Cieneba rocky sandy loam, 8-15% slope, eroded HnC = Honcut sandy loam, 2-8% slope
HnD2 = Honcut sandy loam, 8-15% slope, eroded
LaD2 = Las Posas loam, 8-15% slope, eroded
LaC = Las Posas loam, 2-8% slope
LaC2 = Las Posas loam, 5-8% slope, eroded
LkD2 = Las Posas rocky loam, 8-15% slope, eroded
LkF3 = Las Posas rocky loam, 15-50% slope, severely eroded PsC = Porterville clay
VeC2 = Vallecitos loam, eroded
WyC2 = Wyman loam, eroded
YbC = Yokohl loam, 2-8% slope
YbE3 = Yokohl loam, 8-25% slope, severely eroded
Figure 4
Soils Map
(Photo obtained from Google Earth, February 2016,
USDA Nat. Res. Cons. Serv. SSURGO Data)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
INVESTIGATIONS AND MONITORING
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March 2022
Updated Jurisdictional Delineation
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2.0) REGULATORY ENVIRONMENT
2.1) Jurisdictional Determination of Wetlands, “Waters of the U.S.” The foll owing section describes th e regula tory enviro nment prior to the U.S. Environmental Protection Agency ( EPA) Proposed Rule (described in Section 2.1.3, below ). Three agencies generally regulate activities within streams, wetlands, and riparian areas in California: (1) the U.
S. Army Corps o f Engineers (USACE) regulates acti vities under Section 404 of the federal Clean Water Act; (2) the Regional Water Quality Control Board (RWQCB) regulates activities under Section 401 of the federal Clean Water Act (CWA); a nd (3) the California Depa rtment of Fish and Wildlife (CDFW) regulat es act ivities within under California Fish and Game Code Sections 1600-1616.
2.1.1) Federal Clean Water Act, Section 404
Section 404 of the federal C lean Water Act appl ies to "Waters of the U nited States" (WoUS).
By definition these include waterways that could be used for interstate c ommerce and their tributaries, including any waters wi th a nexus with (ultimately flow into) traditional navigable waters. In non-tidal waters, the limits of j urisdiction are "ordinary high water marks" (OHWM) such as stream banks. Where wetlands occur a bove high water marks, they are considered "adjacent wetlands" and are included within USACE jurisdiction. USACE juri sdiction has often been extended to wetlan ds not adjacent to WoUS ("isolated wetlands"), such as vernal pools.
Under the current administ ration, there have been recent changes to the definition of USACE jurisdictional waters.
According to the Clean Water Act (as amended in 1977) and the Corps of Engineers Wetlands Delineation Manual (1987), a "wetland" is a site that is "inundated or satura ted . . . at a frequency and duration sufficient to support . . . vegetation typically adapt ed for life in saturated soil conditions. . . ." Soil saturation de prives plant roots of oxygen, limiting the types of plants that can grow. Absence of oxygen lea ds to reducing chemical conditions (rather th an oxidizing conditions) and development of uni que soil types (hydric soi ls). Th e USACE eva luates wetlands by thre e crit eria: hydrology, soils, and vegetation. Under the federal delineation procedure, a site must normally satisfy all three criteria to be classified as a wetland.
The hydrology criteri on evaluates the presence of water based on o bserved flooding or inundation or on indirect evidence such as high water marks, drift lines, or sediment deposits.
The soils criterion is based on "hydric" soil c haracteristics, such as certain colors and mott ling Updated Jurisdictional Delineation
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that develop under wetland conditions. These characteristics generally do not develop in sandy soils found in many southern California streambeds. The vegeta tion criterion evaluates plant species growing on a si te. Most plants cannot survive extend ed periods of root saturat ion and are called "obligate upland" species. Others grow almost exclusively in wetlands habitats, while still others may be found growin g in both wetlands and uplands. These are ca lled "obl igate wetlands" or "facultative wetland" species, respectively.
2.1.2) Federal Clean Water Act, Section 401
The RWQCB has jurisdiction over wetlands, WoUS, and Waters of the State un der Section 401 of the CWA and the Porter -Cologne Water Quality Control A ct (Port er-Cologne) under the California Water Code (§ 13000, et. seq.) Permitting is required for activities that will result in a discharge of soils, nutrients, chemicals, detrital materials, or other pollutants into WoUS, Waters of the State, or adjace nt wetla nds that wi ll affect the water qua lity o f those bodies and the watershed.
2.1.3) Evaluation Criteria
According to the Clean Wat er Act (a s amended in 1977) and the Army Corps of Engineers Wetlands Delineation Manual (1987), a "wetland" is a si te that is "inundated or saturated . . . at a frequency and duration sufficient to support . . . vegetation typically adapted for life in saturated soil conditions. . . ." Soil saturation deprives plant roots of o xygen, limiting the types of plants that c an grow. Absence of oxygen leads to reducing chemical conditions (rather than oxidizing conditions) and development of unique soil types (hydric soils). The USACE evaluates wetlands by t hree criteria: hydrology, soils, a nd vegetati on. Under the federal delineation procedure, a site must normally satisfy all three criteria to be classified as a wet land. At its discretion, CDFW may regard a site as a wetland based on only one listed criterion.
The hydrology criter ion eval uates the p resence of water based on obs erved flooding or inundation or on indirect evidence such as high water marks, drift lines , or sediment deposits.
The soils criterion is based on "hydric" soil characteristics, such as certain colors and mot tling that develop under wetland condition s. (T hese characteristics generally do not develop in sandy soils found in many southern Califo rnia streambeds.) The vegetation criterion e valuates plant species growing on a site. Most plants cannot survive extended periods of root saturation and are called "obligate upland" species. Others grow almost exclusively in wetlands habitats, while sti ll others may be found growing in both wetlan ds and up lands. These are called "obligate wet lands" or "facultative wet lands" s pecies, respectively. While the f ederal USACE Updated Jurisdictional Delineation
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criteria are used to evaluate the presence or absence of wetlands within the projec t site, the determination of state wetland st atus is n ot based on the combined presence of t he three criteria because the state can take jurisdiction of any one of the three: (1) the presence of water open or saturated soils, (2) presence of vegetation inc luding riparian or wetland species, and/or (3) water-modified or oxygen-depleted soils.
Traditional Navigable Waters ( TNWs) and Relatively Permanent Waters (RPW s), where water flows for three (3) or more months per year, are jurisdictional by definition; h owever, for Non - Relatively Permanent Waters ( Non-RPWs) data and analysis supporting a “signi ficant nexus” must be provided to justify USACE jurisdiction. Erosional features (i.e., small and large gullies), swales, and excavated roadside ditches are usually not considered jurisdictional.
According to the “U. S. Army Corps of Engineers Jurisdictional Determination Form Instructional Guidebook” (5/30/2007):
Ephemeral wat ers in the arid west that are tributaries may have a significant nexus to a TNW. For exam ple, in some cases they may serve as a critic al transitional area between the upland environ ment and the traditional n avigable waters. S uch ephemeral tributari es, with the associated riparian corridor, may provide refugia, foraging and breeding opportunit ies in areas that may have limited stands of vegetation and water due to the environmental c onditions of the arid southwest. During and following precipitation events, ephemeral tributaries collect and transport water or sometimes sediment from the upper reaches of the landscape to the traditional n avigable waters. These ephemeral tributaries, and associated riparian co rridors, may provid e habitat for wildlife and aq uatic organisms. These biological and physical processes may further support nutrient cycling, sediment retention and transport, pollu tant trap ping and filtration, and improvement of water quality, functions that may affect the integrity of a TNW. . . . S pecifically, an evaluation will be made of the frequency, volume, and duration of flow; pr oximity to the TNW; capacity to transfer nutr ients and organic carbon vital to support food webs; habitat services suc h as pro viding spawning areas for importan t aqua tic species; functions related to the maintenance of water quality such as sediment trappi ng; and other relevant factors. In some cases, even t ributaries that are relatively distant from a TNW may have a significant nexus with the TNW.
The following section describes the proposed changes to the Regulatory Environment which may occurred as a re sult of the EPA Proposed Rule. On December 1 1, 2018, the EPA and Department of the Army sig ned a proposed rule revisi ng the d efinition of "waters of the United States" to clarify federal authority under the Clean Water Act. The agencies’ proposal is the Updated Jurisdictional Delineation
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second step in a two -step process to review a nd revise the definition of “waters of the Unit ed States” consistent with the February 2017 Presidential Executive Order entitled “Restoring the Rule of Law, Federalism, and Economic Growth by Reviewing the ‘Wat ers of the United States’ Rule.” The propose d definition would replace the approach in the 2015 Rule and the pre -2015 regulations:
(a) F or purposes of the Clea n Wate r Act, 33 U.S.C. 1251 et seq. and it’s implementing regulations, subject to the exclusions in paragraph (b) of this section, the term “waters of the United States” means:
(1) Waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including the territorial seas and waters which are subject to the ebb and flow of the tide;
(2) Tributaries of waters identified in paragraph (a)(1) of this section; (3) Ditches that s atisfy any of the condi tions identified in paragraph (a)(1) of this section, ditches constructed in a tributary or that relocate or alter a tributary as long as tho se ditches also satisfy the conditions of the t ributary definition, and d itches constructed in an adjacent wetland as long as those ditches also satisfy the conditions of the tributary definition;
(4) Lakes and ponds that satisfy any of the conditions iden tified in paragraph (a)(1) of this section, lak es and ponds that contribu te peren nial or int ermittent flow to a wat er identified in paragraph (a)(1) of this section in a typical year either directly or indirectl y through a water(s) identified in paragraphs (a)(2) through (6) of this section or through water features identified in paragraph (b) of this section so long a s those water features convey perennial or intermittent flow downstream, and lakes and ponds tha t are flooded by a water identified in paragraphs (a)(1) through (5) of this section in a typical year; (5) Impoundments of w aters ident ified in paragraphs (a) (1) th rough (4) and (6) of this section; and (6) Adjacent wetlands to waters identified in parag raphs (a)(1) through (5) of this section.
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(b) The following are not “waters of the United States”:
(1) Waters or wate r features that are not identified in para graphs (a)(1) through (6) of this section;
(2) Groundwater, including groundwater drained through subsurface drainage systems; (3) Ephemeral features and diffuse stormwater run -off, including directional sheet flow over upland;
(4) Ditches that are not identified in paragraph (a)(3) of this section; (5) Prior converted cropland;
(6) Artificially irri gated areas, including fields flooded for ric e or cran berry growing, that would revert to upland should application of irrigation water to that area cease; (7) Artificial lakes and ponds constructed in upland (including water storage reservoirs, farm and stock watering ponds, and log cleaning ponds) which are not identified in paragraph (a)(4) or (a)(5) of this section;
(8) Water-filled depressions created in upl and incidental to mining or construction activity, and pits excavated in upland for the purpose of obtaining fill, sand, or gravel; (9) Stormwater control features excavated or constructed in upland to convey, treat, infiltrate or store stormwater run-off;
(10) Wastewater recycling structures constructed in upland, such as detention, retention and infiltration basins and ponds, and groundwater recharge basins; and (11) Waste treatment systems.
(c) Definitions. In this section, the following definitions apply:
(1) Adjacent wetlands. The term adjacent wetlands means wetlands that abut or have a direct hydrologic surface connection to a water ide ntified in paragraphs (a)(1) through (5) of this section in a typical year. Abut means to touch at least at one point or side of a water identified in paragraphs (a)(1) through (5) of this section. A direct hy drologic surface connection occurs as a resul t of inundation from a paragraph (a)(1) through (5) water to a wetland or via per ennial or i ntermittent flow betwee n a we tland and a Updated Jurisdictional Delineation
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paragraph (a)(1) through (5) water. Wetlands physically separated from a para graph (a)(1) through (5) water by upland or b y dikes, barriers, or similar structures and al so lacking a direct hydrologic surface connection to such waters are not adjacent. (2) Ditch. The term ditch means an artificial channel used to convey water. (3) Ephemeral. The term ephemeral means surface water flowing or pooling only in direct response to precipitation (e.g., rain or snow fall).
(4) High tide line. The term high tide line means the line of intersection of the land with the water’s surface at the maximum height reached by a rising tide. The high tide line may be determined, in the abs ence of actual data, by a line of oil or scum along shore objects, a more or less continuous deposit of fine shell or debris on the foreshore or berm, other physical markings or characteristics, vegetation lin es, tidal gages, or other suitable means that d elineate the general heigh t reache d by a risi ng tide. The line encompasses spring high tides and other high tides that occur with periodic frequency but does not in clude storm surges in which there is a depart ure from the normal or predicted reach of the tide due to the piling up of water against a coast by strong winds, such as those accompanying a hurricane or other intense storm. (5) Intermittent. The term interm ittent means surface water flowing continuous ly during certain times of a typical year and m ore than in direct respons e to pre cipitation (e.g., seasonally when the groundwater table is elevated or when snowpack melts). (6) Ordinary high water mark. The term ordinary high water mark means that line o n the shore established by the fluctuations of water and indicated by phy sical characteristics such as clear, natural line impressed on the bank, shelving, changes in the character of soil, destruction of terres trial vegetation, the presence of litter and debris, o r other appropriate means that consider the characteristics of the surrounding areas. (7) Perennial. The term perennial means surface water flowing continuously year -round during a typical year.
(8) Prior converted cropland . The term prior conve rted cropland means any area that, prior to December 23, 1985, was draine d or otherwise manipulated for the purpose , or having the effect, of making production of an agricultural product possible. EPA and the Corps will recognize designations of prior con verted cropland made by the Secretary of Agriculture. An area is no long er considered prior converted cropland for purposes of Updated Jurisdictional Delineation
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the Clean Water Act when the area is abandoned and has reverted to wetland, as defined in paragraph (c)(15) of this section. Abandonment occurs when prior converted cropland is not used for, or in sup port of, agricultural purposes at least on ce in the immediately preceding five years. For the purposes of the Clean Water Act, the EPA Administrator shall have the final authority to determine whether prior converted cropland has been abandoned.
(9) Snowpack. The term snowpack means layers of sn ow that accumulate over extended periods of time in certain geographic regions and high altitude s (e.g., in northern climes and mountainous regions).
(10) Tidal waters and waters subject to the ebb and flow of the tide. The terms tidal waters and waters subject to the ebb and flow of the tide mean those waters that rise and fall in a predictable and measurable rhythm or cycle due to the gravitational pulls of the moon and sun. Tidal waters and waters subject to the ebb and flow of the tide end where the rise and fall of the water surface can no longer be practically measured in a predictable rhythm due to masking by hydrologic, wind, or other effects. (11) Tributary. The term tributary me ans a river, stream, or si milar na turally occ urring surface water channel that contributes perennial or intermittent flow to a water identified in paragraph (a)(1) of this section in a typical year either dire ctly or indirectly through a water(s) identifie d in paragraphs (a)(2) thr ough (6) of this se ction or through water features identified in paragraph (b) of this section so long as those water features convey perennial or intermittent flow downstream. A tributary does not lose its status as a tributary if it flows through a culve rt, dam, or other similar artificial break or through a debris pile, boulder field, or similar natural break so long as the artificial or natural break conveys perennial or intermitte nt flow t o a tributary or other jurisdictional water at the downstream end of the break. The alteration or relocation of a tributary does not modify its status as a tributary as long as it continues to satisfy the elements of this definition. (12) Typical year. The term typical year means within the normal range of precipitat ion over a rolling thirty-year period for a particular geographic area. (13) Upland. The term upland means any land area that under norma l circumstances does not satisfy all three we tland delineation criteria (i.e., hydrology, hy drophytic vegetation, hydric soils) identified in paragraph (c)(15) of this section, and does not lie below the ordinary high water mark or the high tide line of a water identified in paragraph (a)(1) Updated Jurisdictional Delineation
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through (6) of th is section. Waters identified in parag raphs (a)(1) through (6) o f this section are not upland.
(14) Waste treatment system. The term waste treatment system includes all components, including lagoons and treatment ponds (such as settling or coolin g ponds), designed to convey or retain, concent rate, settle, reduce, or r emove po llutants, e ither actively or passively, from wastewater prior to discharge (or eliminating any such discharge). (15) Wetlands. The term wetlands means areas that are inundate d or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soi l conditions. Wetlands generally include swam ps, marsh es, bogs, and similar areas.
2.1.4) Federal Clean Water Act, Section 401
The RWQCB has jurisdiction over wetlands, WoUS, and Waters of th e State under Section 401 of the CWA and the Porter-Cologne Water Quality Control Act (Porte r-Cologne) under the California Water Code (§ 13000, et seq.) Permi tting is required for activities that will result in a discharge of soils, nutrients, chemicals, detrital materials, or other pollutants into WoUS, Waters of the State, or adjacent wetland s that will affect the wat er quali ty of those bodies and the watershed.
At the time of the publication of this report no clear direction as to the new rule was avai lable, consequently we have submitted this re port assuming the presence of Federal Waters of the US. In the event tha t the EP A Proposed Rule goes into effect, L&L will revise this report to indicate no Federal Waters are present on the property.
2.1.5) California Fish and Game Code, Section 1600
The CDFW, through provisions of the California Fish and Game Code (Sections 1600 -1616), is empowered to issue agreements (“Lake and Streambe d Alteration Agreements”) for projects that will adversely affect wildlife habitat associate d with any river, stream, or lake edges. The Lake and Streambed Alt eration Agreement will typically include required measures to mitigate impacts.
Sections 1600-1616 of the California Fish and Game Code apply to stream channels, defined elsewhere in the Code as follows:
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"A stream is a bod y of water that flows at least per iodically through a bed or channel having banks and supports fish or other aquatic life. This i ncludes watercourses having a surface or subsurface flow that supports or has supported riparian vegetation." The state definition does n ot specify a flow rate or inundation frequency and provides no clear distinction between jurisdictional and non-jurisdictional lands.
While the federal USACE criter ia (hydro logy, soils, and vegetation) are used to evaluate the presence o r absenc e of wetlan ds within the project s ite, t he determination of state wetland status is not based on the combined presence of the thre e criterion because the state can take jurisdiction of any one of the three: (1) the presenc e of open water or saturat ed soils , (2) presence of vegetation inclu ding r iparian or wetland species, and/or (3) water -modified or oxygen-depleted soils.
2.2) Western Riverside County Multiple Species Habitat Conservation Plan The County of Riverside, including eight (8) additional land jurisdictions and 14 cities, have prepared a Multiple Species Habitat Conservation Plan (MSHCP) for western Riverside County (Dudek 2003a, 2003b). The MSHCP will build upon existing preserves and provide connectivity and wildlife corridors throughout the region. The MSHCP proposes to conserv e approximately 500,000 acres and 146 different species.
The MSHCP was approved by the cou nty on June 17, 2003 and an Implementation Agreement (IA) between the USFWS, the CDFW, and the County was executed and an associated USFWS Section 10(a)(1)(B) Permi t (No. TE -088609) was issued on June 22, 2004. The pe rmit grants take authorization for cer tain species identified in the permit as "Covered Species Adequately Conserved."
The MSH CP establis hes seven (7) core reserve areas and associated linkages between proposed and existing core areas. The MSHCP divides a reas into Cells using USGS coordinates. Acco rding to the Riverside County Integrated Project website parc els th at compose the current pr oject site are located within Sun City/Menifee Valley Area Plan.
Conservation efforts for the project site will be eva luated with regard to sensitive specie s identified as not adequately conserved and observed onsite, riveri ne/riparian or verna l pool habitat and their associated sensitive species (if located onsite), f airy shrimp, jurisdictional areas, and sage scrub.
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MSHCP Section 6.1.2 (Riparian/Riverine Habitat)
Section 6.1.2 of the MSHCP requires an assessment of the potentially significant effects of the proposed project on Riparian/riverine areas, and vernal pools as curr ently required by C EQA using available information augmented by project-specific mapping. Riparian/riverine areas and vernal pools are defined as follows:
• Riparian/riverine Areas are lands that have flow for all or a portion o f the year and which contain habitat dominated by trees, shrubs, persistent emergents, or emergent mosses and lichens, which occur close to or which depend upon soil moisture from a nearby fresh water source; or areas with fresh water flow during all or a portion of the year. • Vernal p ools are season al w etlands that occur in depression areas that have wetlands indicators of al l three p arameters (soi ls, vegetation, and hydrology) during the wett er portion of the gro wing sea son but normally lack wetlands ind icators o f h ydrology and/or vegetation during the drier portio n of the growing seas on. Obligate h ydrophytes and facultative wetlands plant species are normally dominant during the wetter portion of the growing season, while upland species (annuals) may be dominant during the drier portion of the growing season. The determination that an area exhibits vernal pool characteristics, and the definition of the wa tershed supporting vernal pool hydrology, must be made on a case-by case basis. Such determinations should consider the length of the time the ar ea exhibits upland and we tland characteristics and t he manner in which the area fits in to the overall ecological system as a wetland. Evidence concerning the persistence of an area’s wetness can be obtained from its history, vegetation, soils, and drainage ch aracteristics, uses, to which it has been subjected, and weather and hydrologic records.
With the exception of wetlands created for the purpose of providing wetlands habitat or resulting from hu man actions to create open waters or fr om t he alteration o f na tural stream courses, areas demon strating charac teristics as described abo ve which are artificially create d a re n ot included in these definitions.
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3.0) METHODS
3.1) Literature Review
Potential occ urrence of state and federal wetlands and waters on the proj ect site were evaluated through a literature review including the jurisdictional delineation conducted by L&L in 2011 (L&L 2012) and updated in 201 8/2019 (L&L 2019) as well as reports of other previous surveys of the site, as needed (L&L 2003-2021). Literature reviewed also included soils maps and descriptions (Knecht 1971), topographic maps ( USGS 1979), and the list of wetland plants in California (Appendix O to the Delineation Manual). Recent and historical aerial photographs of the project site and jurisdictional areas were reviewed and helped document the slow decline of the riparian habitat onsite. These images dated from 1938 through 2021 (Google Earth 2021, NETRonline 2021).
3.2) Jurisdictional Delineation Survey Methods
Soil maps and descriptions of local soils were reviewed (NRCS 2018). Soils mapped on the project si te were listed and evaluated for their properties rela ting to potential wetlands. Soil conditions onsite were noted during field visits. Soil color characteristics were evaluated using a “Munsell color chart.”
During field surveys, vegetation growing within features was examined. Dominant plant species were listed along with any potential indi cators of wetland conditions. The U. S. Army Corps of Engineers (Co rps), as part of an interagency effort with the U. S. Enviro nmental Protection Agency (EPA), the U. S. Fish and Wildlife Serv ice (FWS) , and the U. S. Department of Agriculture Natural Reso urces Conservation Service (NRCS), has developed a Nati onal Wetland Plant List (NWPL). The NWPL is used to determine whether th e hydrophytic vegetation parameter i s met when conducting wetland determinations under the Clean Water Act and the Wetland Conse rvation Provisions of the Food Security Act. Other app lications of the li st include wetland restoration, establishment, and enh ancement projects. The list was effective on May 1, 2016 and is used in a ny wetland delin eation performed after this date.
Delineations received prior to this date may still use the 2014 NWPL or may choose to use the 2016 list. The reference list used m ust be identified on any wetland del ineation/determination forms. The vegetation criterion for wetlands is satisfied if half or more of the dominant plant species in an area are rank ed as "obliga te wet land," "facultative wetland," or "facultative" species (OBL, FACW, or FAC, respectively, see Table 1).
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 19 L&L
A recent biological asses sment (L&L 2021) field reconnaissance, May and June 2021, addressed vegetation and other biolog ical resources on the proje ct sit e, which aided in the mapping of reduced arroyo willow/mulefat wetland habitats. This field reconnaissance supported by a desktop analysis of re cent aerial images (Google Earth 2021) was used to map current conditions and identify changes from the 2011 and 2018/2019 jurisdictional delineations.
Table 1. Summary of Wetlands Vegetation Criteria
Category Probability
Obligate Wetland (OBL) Almost always occur in wetlands (estimated probability >99%) Facultative Wetland (FACW) Usually occur in wetlands (Estimated probability 67%-99%) Facultative (FAC) Equally likely to occur in wetlands and non-wetlands (est. probability 34%-66%) Facultative Upland (FACU) Usually occur in non-wetlands (estimated probability 67%-99%) Obligate Upland (UPL) Almost always occur in non-wetlands (estimated probability >99%)
3.3) MSHCP Riparian/Riverine and Vernal Pools
In conformance with the MSHCP, this report addresses riparian/riverine areas a nd vernal pools within the feature des criptions of each system. Where rip arian vegetation i s associated with features (and to the extent that it is native to California), we considered it suitable for a designation as riparian under the MSHCP. Where flows evidence some level of energy, at least ephemerally, we considered them riverine in the broadest sense.
To meet the defini tion of a vernal pool, three (3) factors must be addressed: suitable soi ls and soils conditions, proper hydrology, and one or more indicator species.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 20 L&L
4.0) RESULTS
4.1) Literature Review Results
The 2011 jurisdictional delineation conducted b y L&L found that the jurisdictional areas identified on the project site were calculated as 6,080 sq. ft. (0.140 acre) of CDFW unvegetated state streambed and 50,634 sq. ft. (1.162 acre) o f CDFW state wetland. The survey also identified 2,631 sq. ft. (0.060 acre) of USACE WoUS, none of which is USACE federal wetland.
The 2018 update to the jurisdictional delineation incorporated two culverts along Wickerd Road, resulting in increased offsite impacts to state and federal jurisdictional features. Jurisdictional areas identified within the property include 6,657 sq. ft. (0.153 acre) of CDFW unvegetated state waters/streambed (which is also MSHCP Riverine habitat) and 52,627 sq. ft. (1.208 acres) of CDFW state wetland (which is also MSHCP Riparian habitat). The survey also identified 2,828 sq. ft. (0.065 acre) of USACE WoUS, none of which is USACE federal wetland.
A review of re cent and historic aerial s shows that the project site has been under cultivation since at least 1938 (Google Earth 2021, NETRonline 2021). The drainage is visible in 1938 but appears to include little shrubby vegetation. On the aerials taken in 1967 and 1 978, the drainage does not appear to include any shrubby vegetation. By 1996, the drainage appears to have patches of vegetation, assu med to be native riparian shrubs and trees , alon g some portions of its length on the proje ct site . In aerials dated from 2002 through 2021, the vegetation in the drainage becomes vi sibly less dense and shrinks in most places to individua l or very small bunches of trees and bushes. This corresponds to observations during surveys by L&L from 2003 through 2021, which indicate that riparian vegetation has declined considerably in recent years and portions of the riparian area have been incorporated into the croplands.
4.2) Vegetation Communities
Much of the s ubject property has been disturbed by his toric and current cultivation an d sheep grazing and does not support native habitat. Less disturbed areas are present, primarily in the northeastern portions of the site, with a mixture of disturbed and relatively undisturbed California buckwheat scrub and chamise chaparral. Sparse riparian vegetation and trees are found along a portion of the USGS mapped blue-line stream area in the northwestern/central portion of the site (Figure 5). A list of all plants and wildlife observed on the site is provided in Appendix C.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 21 L&L
4.2.1) California Buckwheat Scrub
Relatively undisturbed California buckwheat scrub (previously Holland Riversidean sage scrub) is present on the eastern and northern (primarily northeastern) portion of the site on south, west, and east -facing slopes containing numerous rocky outcrops. Native shrubs and other conspicuous plants commonly observed in these areas include California buckwhe at (Eriogonum fasciculatum), California sagebrush ( Artemisia californica), and white sage ( Salvia apiana). Other conspicuous plants include brittlebush ( Encelia fari nosa), yellow bush penstemon ( Keckiella antirrhinoides ), wishbone bush ( Mirabilis laevis var. crassifolia), sweetbush ( Bebbia juncea ), blue elde rberry ( Sambucus nigra ssp. cerulea), and black sage (Salvia mellifera ). Open patches can be found throug hout p ortions of the b uckwheat scrub onsite containing a mixture of native and non-native annuals.
4.2.2) Chamise Chaparral
Small patches (or islands) of remnant chamise chaparral (Adenostema fasciculatum Shrubland Alliance) or chamise –black sage chaparral ( Adenostema fascicul atum–Salvia mellifera Shrubland Alliance) (previously Holland northern mixed chaparral) were observed, excluding the east-central property boundary where some relatively dense stand s remain and m ix with California buckwheat scrub (especially just offsite to the east). Common species found in the chaparral areas onsite are chamise ( Adenostoma fasciculatum ), black sage, and o ther perennials. A poorly developed understory is usually present i n asso ciation with cha parral areas and is characteristic of areas observed on the subject site and in adjacent areas.
4.2.3) Arroyo Willow Thickets and Mulefat Thickets
Arroyo willow thickets ( Salix lasiolepis Shrubland All iance) and mulefat thickets ( Baccharis salicifolia Shrubland Alliance) (previously Holland sou thern arroyo wi llow riparian and mulefat scrub) are dependent on the presence of at least periodic surface or subsurface water. The northwestern portion of the site contains a degraded USGS mapped blue-line stream sp arsely inhabited by arroyo willow ( Salix lasiolepis), mulefat (Baccharis salicifolia), or a combination of these species. A single Fremont cottonwood tree ( Populus f remontii ssp. fremontii) and scattered non -native tamarisks ( Tamarix species) were also ob served. The understory is dominated by mostly weedy a nnuals, including (but not limited to) short-pod mustard, annual sunflower, fiddleneck, Spanish clover ( Acmispon americanus), wild radish ( Raphanus sativus), mayweed (Anthemis cotula), prickly lettuce ( Lactuca serriola), and several non -native grasses, including common wheat (Triticum aestivum) and oat (Avena species).
Updated Jurisdictional Delineation
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Surface water was not observed within any of the onsite drainage features during biological surveys in 2013 or 2017 an d none was observed during the jurisdictional delinea tion in 2011 and fie ld reconnaissance in 2018 or 2021 . These areas app eared to be considerably less densely populated with riparian shrubs and trees in 2021, when compared to previous surveys.
This may be due to the prolonged drought that affected this area in recent years (approximately 2010 to 2016).
4.2.4) Agriculture and Disturbed/Ruderal
Agriculture is not included under the more recent Sawyer et al. (2009 ) classification utilized by CDFW. Disturbed/ruderal areas that ar e strongly dominated by a nnual non -natives may be classified as semi -natural stands, such as Brassica (nigra) and Other Mustar ds Semi -natural Herbaceous Stands or Bromus rubens —Schismus (arabicus, barbatus) Semi -natural Herbaceous Stands.
The majority of the site has been under consistent cultivation, mainly dry-farmed wheat crops.
Invasive plants were observed uncommonly within flatland p ortions of the site, i ncluding lamb’s quarters ( Chenopodium murale ), cala bazilla ( Cucurbita foetidissima ), and knotweed (Polygonum aviculare).
Disturbed habitat includes unvegetated areas (such as roads) and area s that contain mostly non-native plant species, including ornamentals and ruderal invasive species. Some non-native and weedy species have invaded th ese areas, including short -pod mustard, foxtail chess, red - stemmed filaree (Erodium cicutarium), and various non-native grasses. Other non -native plant species obs erved in these areas include horehound (Marrubium v ulgare), Russian thistle (Salsola tragus), and tumbling pigweed (Amaranthus albus).
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 23 L&L
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
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Figure 5
Vegetation Community Map
(Photo obtained from Google Earth, August 2021)
Golden Meadows, TT 31194
City of Menifee, California
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 24 L&L
4.3) State and Federal Jurisdictional Areas
The nearest Traditionally Navigable Water (TNW) is Canyon Lake (the nearest point of which i s approximately 3 miles straight northwest o f the project area). Ca nyon Lake connects to Lake Elsinore and on to the Pacific Ocean (Figure 6). However, between th e Paloma Valley High School Channel and Canyon Lake th ere is a flood plain, so very high pre cipitation would be required for any surface water to reach Canyon Lake. All features onsite match Cowardin Code R6 (Riverine, Ephemeral).
Land use and cultivation patterns changed slightly over the years of L&L studies on the property beginning in 2003, during which annual rainfall levels have fluctuated. During each of the calendar years between 2003, 2006, 2011, 2017, 2 018 and 2019 when L&L studied or otherwise visited the property, wheat crop propagation was occur ring on the cleared portions of land surrounding the riparian vegetation. Dry areas and gaps in the veget ation appear to have been incorporated into t he wheat crop production. Downstream, the developm ent of the adjacent tract has created a large paseo an d this is “misaligned” with the histor ic blue-line, resulting in some shifting of the waters/riparian vegetation in our study area.
Jurisdictional areas identified w ithin the property include 18,814 sq. ft. (0. 43 acre) of CDFW unvegetated state waters/streambed (which is also MSHCP Riverine habitat) and 40,451 sq. ft. (0.93 acres) of CDFW state wetland (which is also MSHCP Riparian habitat). The survey also identified 4,397 sq. ft. (0. 10 acre) of USACE WoUS, none of which is USACE federal wetland.
Feature 1
Feature 1 (F1) runs from the center portion of the property to the northwestern boundary. This feature measures 1,128 linear feet (lf) and runs from south to north . Feature 1 is comprised of 6,842 sq. ft. of CDFW state streambed (MSHCP Riverine habitat), 15,916 sq. ft. of CDFW wetland (MSHCP Riparian habitat) and 1290 sq. ft. (430 lf) of WoUS.
Feature 1b
Feature 1b (F1b) is an isolated fea ture that measures 358 lf . and runs from south east to northwest within the center of the site. It is comprised of 1,797 sq. ft. of CDFW state streambed (MSHCP Riverine habitat), 2,751 sq. ft. of CDFW wetland (MSHCP Riparian habitat) and 716 sq. ft. (358 lf) of WoUS . Observations in the field, verified by agency personnel, have determined that the feature is isolated and there is no evidence of surface connection.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 25 L&L
Figure 6
Connection to Pacific Ocean
(Photo obtained from Google Earth, 6-7-2012)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
INVESTIGATIONS AND MONITORING
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Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 26 L&L
Feature 2
Feature 2 (F2) measures 1042 lf and runs from south to north within the northwestern portion of the site parallel to Feature 1. Feature 2 is comprised of 8,275 sq. ft. of CDFW state streambed (MSHCP Riverine habitat), 20,913 sq. ft. of CDFW wetland (MSHCP Riparian habitat) and 1806 sq. ft. (602 lf) of WoUS.
Feature 3
This “feature” shows no evidence of beds or banks. No jurisdictional streambed is present.
Feature 4
This offsite feature is the easternmost of the two sma ll drainages that cross Wickerd Road. It measures 188 lf; 1,289 sq. ft. of CDFW state streambed (MSHCP Riverine habitat), 871 sq. ft. of CDFW wetland (MSHCP Riparian habitat) and 325 sq. ft. of WoUS (130 lf).
Feature 5
This offsite f eature is the westernmost of th e two small drainages that cross Wickerd Road. It measures 130 lf; 611 sq. ft. of CDFW state streambed (MSHCP Rive rine habitat), with no CDFW wetland or MSHCP Riparian habitat present and 260 sq. ft. WoUS (130 lf).
Cubic yards (cy) of fill is calculated for WoUS as follows: Feature 1 - 0 cy, Feature 1b - 239 cy, Feature 2 - 0 cy, Feature 3 - 0 cy, Feature 4 – 45 cy, and Feature 5 - 5 cy, for a total proposed fill in WoUS of 289 cy of fill.
Unconnected Features
Several other unconnected features were identified from aerial photos and were analyzed in the field (Figure 7). All of these feature s appear to be erosional and related to an unimproved road system. The area surrounding these features is highly disturbed and, at the time o f our fieldwork, show ed no connection to other features. F urther, they neither received nor transported flows off property. As a result, we did not include them in further discussions.
Post-project BMPs
Post-construction BMPs include minimizing urban runoff, minimizing impervious footprint, conserving natural areas, and minimizing Directly Connected Impervious Areas (DCIAs). BMPs Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 27 L&L
have been provided in order to address water quality in low flows and first flush storm runoff, as well as to control post-construction peak flow volumes.
A combination of dete ntion basins and infiltration basins will be constructed on site as post- construction Best Management Practice s. The design of these facilities is in accordance with published standards from the Riverside County Flood Control and Water Conservation District.
The project proponent will construct the facility according to local standards, requi rements, and specifications, and will maintain the facility until the Homeowner’s Association is established.
Upon formation of the HOA, they will assume maintenance responsibilities, which will be funded through monthly homeowner assessments.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 28 L&L
1 Figure 7
Jurisdictional Delineation
(Photo obtained from Google Earth, 3-9-2011)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
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INVESTIGATIONS AND MONITORING
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1 1b
4 2
3 5
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 29
4.4) MSHCP Riparian/Riverine and Vernal Pool Habitat
Under MSHCP Volume 1 Section 6.1.2, areas associated with wetland and streambed systems must be evaluated for consideration as riparian/riverine or vernal pool habitat. Riparian/riverine areas are defined within the MSHCP as:
“. . . lands which contain Habitat dominated by trees, sh rubs, persiste nt emergents, or emergent mosses and lichens, which occur c lose to or which depend upon soil moisture from a nea rby fresh water source; or areas with fresh water flow during all or a portion of the year.” MSHCP Vol. 1, Section 6.1.2.
The subject site cont ains woody water dependen t vegetation. Arroyo willow (Salix lasiolepis), cottonwood (Populus fremontii ), and mu lefat (Baccharis salicifolia ) are present within th e mapped features (Figure 5). Fresh water flows through the ephemeral stream t hat is present and mapped as a USGS blueline.
Vernal pools are defined within the MSHCP as:
“. . . seasonal wetlands that occu r in depression areas that have wetlands indicators of all thre e parameters (soils, vegetation and hydrology) during the wetter po rtion of the g rowing season but normall y lack wetla nds indicators of hydrology and/or vegetation during the drier portion of t he growing season.
Obligate hydrophytes and facult ative wetlan ds plant species are normally dominant during the wetter portion of the growing s eason, while upland speci es (annuals) may be dominant durin g the drier portion of the growing season. . . .” MSHCP Vol. 1, Section 6.1.2.
Soil types within the st udy area are not consistent with an alkali playa or vernal pool complex and poo ls or depressi ons characteristic of ver nal habitat were not noted as pres ent on the subject property. No MSHCP species listed for protection associated with riparian/riverine areas and ver nal pools were observed. No fairy shrimp or fairy shrimp habitat w as observed during this study.
The updated jurisdictional delineation fou nd 18,814 sq. ft. (0. 43 acre) of Western Riverside County MSHCP Riverine habitat and 40,451 sq. ft. (0.93 acres) of MSHCP Riparian habitat.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 30
5.0) AVOIDANCE MINIMIZATION AND MITIGATION STRATEGY
5.1) Evaluated Alternatives
Five (5) altern atives were examined during development planning regarding impacts to jurisdictional areas:
1. Proposed Action entails use of the ent ire area of all owned parcels for a housing development and the impact of all features. Since the entire site would be utiliz ed, the only post-project flow of water onsite would be associated with storm water runoff a nd water quality basins ne cessary to r educe flooding and fo r so me nutrient and waste processing. All mitigation for impacts would occur offsite. This alternative was judged to be infeasible because it failed to achieve the requirement to mi nimize and avoid impacts to jurisdictional areas.
2. Reduced Federal Action includes avoidance of most jurisdictional features (particularly the higher quality portions) and onsite reconstruction and restoration of a significant area surrounding avoided juri sdictional are a. This alternative would impact 2,657 sq. ft. (0.061 acre) of CDFW state streambed and 10,983 sq. ft. ( 0.252 acre) of CDFW state wetland. A total of 1,521 sq. ft. (0.035 acre) of federal WoUS would be impacted. The project proposes to avo id 41,644 sq. ft. (0.956 acre) of riparian habitat and 4,000 sq. ft. (0.092 a cre) of unvegetated drainages. Onsite mitigation includes a total area of 156,380 sq. ft. (3.59 acre and 416 lf), of which 0.96 acre of state wetland is avoided and preserved, 0. 092 acre of st ate streambed and 0.03 acr e of WoUS is avoided and restored, and an additional 2.63 acres of state streambed/WoUS is restored by the removal of debris, exotic tamarisk, and weeds. This alternative is feasible because it minimizes impacts and avoids, enhan ces, and restores jurisdic tional areas and riparian/riverine ha bitat that have been damaged by dryland farming i n the area.
However, p reserved and restored habitat would be su rrounded by residential development and habitat value would subseq uently be much lower than habitat that i s part of a larger contiguous block of open space.
3. No Jurisdictional Impacts Alternat ive would require avoidance of all jurisdictional areas within t he owned parcels. Dryland farming and /or grazing activities would continue to occur, no conservation of the remaining riparian vegetation would occur, and no reconstruction or restoration act ivities would occur. This option is considered impractical beca use it would not allow for infrastructure and circulation elements Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 31
required to s upport housing in the area and the red uction of allowed uni ts m akes this project alternative infeasible.
4. Offsite Alternative would involve purchasing an equivalent sized property with no jurisdictional areas present. This alternative was jud ged to be impractical when the cost of engineering, land planning, and the value of the current land was considered.
5. Compatible Use Alternative would incorporate the existing ons ite drainages into the compatible use areas. This alternative would impact 9,541 sq. ft. (0.22 acre) of CDFW streambed and 5,702 sq. ft. (0.13 acre) of CDFW state wetland. A total of 1,301 sq. ft. (0.03 acre) of federal WoUS would be impacted. Further, the project proposes to incorporate the remaining jurisdictional areas on the site into the Compatible Use Area:
9,273 sq. ft. (0 .21 acre) of stat e streamb ed and 34,749 sq. ft. (0.80 acre) of state wetland, including 3,096 sq. ft. (0.07 acre) of WoUS. Offsite mitigation at no net loss to functions and values would be accomplished through purchase of credits at an approved mitigation bank. This is feasible because it compensates for impacted jurisdi ctional areas through offsite preservation of habitat that is part of a larger contiguous area of habitat. Habitat value would co nsequently be substantially higher than onsite habitat surrounded by deve lopment ( i.e., Alternative 2). This alternative was discussed and agreed to at a meeting between Richland, L&L , USFWS, CDFW, RWQCB, USACE, and the Western Riverside County Regional Conservation Authority on April 11, 2018.
5.2) Least Environmentally Damaging Practical Alternative L&L evaluated all five alternatives and found that Alternative 5, the Compatible Use Alternative, meets the project goal of providing residential housing in the Menifee area and compensates for impacts to jurisdictional areas and riparian/riverine habitat by providing increased habitat value.
Compatible Use
Compatible use areas allow for the continued use of the land as has been occurr ing but in general allow for non-destructive uses.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 32
6.0) CONCLUSIONS
The purpose of th is study was to verify and update the results of a 2011 jurisdictional delineation tha t identified jurisdictional wate rs/wetlands and MSHCP Riparian/Riverine areas present onsite and to determine wh ich areas of the property would be impacted by planned development.
The jurisdictional areas identified on the project site were updated as 18,814 sq. ft. (0.43 acre) of CDFW unvegetated state streambed and 40,451 sq. ft. (0.93 acres) of CDFW state wetland.
The survey also identified 4,397 sq. ft. (0.10 acre) of USACE WoUS, none of which is USACE federal wetland. A total of 59,265 sq. ft. (1. 361 acres) of Western Riverside Cou nty MSHCP Riparian/Riverine habitat w as identified within the proposed project area (see Figure 7 and Table 2 in Appendix A).
The curren t developmen t plan indicates impacts to 9,541 sq. ft. (0. 22 acre) of CDFW state streambed, 5,702 sq. ft. (0. 13 acre) o f CDFW state wetland, and 1,301 sq. f t. (0. 03 acre) of USACE WoUS. Further, the project proposes to retain 9,273 sq. ft. (0. 21 acre) of s tate streambed and 34,749 sq. ft. (0.80 acre) of state wetland, including 3,096 sq. ft. (0.07 acre) of WoUS, by incorporating these areas onsite within a Compatible Use Area.
Regulatory agency permits/agreements and an MSHCP Determination of Biologically Equivalent or Superior Preservation (DBESP) will be required before project-related impacts occur.
This document has been prepared to assist in planning and to accompany permit applications or agreements under federal or state law.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 33
Figure 8
Water Resources with Dev.
(Plan obtained from Hunsaker & Assoc. Irvine, Inc., 2021)
Menifee Assemblage, TT 31194
City of Menifee, California
L&L Environmental, Inc.
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1 1b
4 2
5 Compatible Use Area
Updated Jurisdictional Delineation
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7.0) REFERENCES
CDFW (C alifornia Dep artment of Fish an d Wildlife). 2018. California Natural Diversity Database. RareFind 5. https://www.wildlife.ca.gov/Data/CNDDB/Maps-and-Data.
Dudek (Dudek & Associates, Inc.). 2003a. Western Riv erside County MSHCP, Vol. I. The Plan.
_____. 2003b. Western Riverside County MSHCP, Vol. II-A through E, The MSHCP Reference Document.
Environmental Laboratory. (1987). Corps of Enginee rs Wetland s Delineation Manual, Technical Report Y -87-1, U. S. Army Engineer Waterways Experiment Station, Vicksburg, MS.
Waters of the US Rulemaking: EPA and Army Propose Revised: Waters of t he US Definiti on. https://www.epa.gov/wotus-rule
Google Earth. 2018. Google Earth Pro 7.3.1.4507.
Knecht, A. A. 1971. Soil survey of western Riverside area, Calif ornia. U. S. Department of Agriculture, Soil Conservation Service. https://casoilresource.lawr.ucdavis.edu/gmap/
L&L (L&L Environmental, Inc.). 2003a. General Biological Survey Report for the Menifee Tract 31194 Riverside County, California.
_____. 2003b. Jurisdictional Delineation for the Menifee Assemblage APN #360-300-002, 003- 006, 008, and 360-350-001, Menifee, Riverside County, California.
_____. 2 004a. A Spring Botanical Survey, on Tract 31194, Men ifee Assemblage, Riverside County, California.
_____. 2004b. Focused Su rvey for the Quino Checkerspot Butterfly on Tract 31194, Menifee Assemblage, Riverside County, California.
_____. 2004c. Focused Survey for the Coastal California Gnatcatcher on Tract 31194, Menifee Assemblage, Riverside County, California.
_____. 2005. A Burrowing Owl Species Survey for the Menifee Assem blage Project Menifee, Riverside County, California.
_____. 2 006a. Foc used Breeding Season Burrowing Owl Habitat Assessment and Burrow Survey for Menifee Assemblage, Riverside County, California.
_____. 2006b. Focused Least Bell’s Vireo and Southwest ern Willow Fly catcher Survey and Habitat Assessment for Yellow-Billed Cuckoo for the Menifee Assemblage Site, County of Riverside, California.
_____. 2007. Focused Br eeding Season Burrowing Owl Hab itat Assessment and Burrow Survey for Menifee Assemblage, Riverside County, California.
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_____. 2012. Rev ised Updated Biological Assessment, Burrowing Owl, and Jurisdictional Delineation Surveys for TR 31194, Golden Meadows, City of Menifee, California.
_____. 2017. Biological Assessment and Botanical Surv eys for Tract 31194, Golden Meadows, City of Menifee, California.
_____. 201 9. Updated Jurisdictional Delineation for TR 31194, Golden Meadows, City of Menifee, California.
NETRonline (Nationwide Environmental Title Research, LLC). 2017. Historical aerials. https://www.historicaerials.com/viewer
NRCS (USDA Natur al Resources Conservation Service). 2017. Soil Survey Geogr aphic [SSURGO] Database.
http://www.ncgc.nrcs.usda.gov/products/datasets/ssurgo/index.html
NWPL 2018 National Wetland Plant List:
http://wetland-plants.usace.army.mil/nwpl_static/v33/home/home.html
Sawyer, John O., T. Keeler-Wolf, and J. M. Even s. 2009. A Manual of California Ve getation, 2nd Edition. California Native Plant Society, Sacramento, California. 1300 pp.
USGS (U. S. Department of the Interior Geological Survey). 1979. Romoland California 7.5 - Minute topographic map. USGS, Denver, Colorado.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 36
APPENDIX A
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 37
Table 2. Summary of wetlands criteria and jurisdiction.
Feature
Lat/Long
(UTM)
Cowardin
Code
HGM
Code
Length
(ft.)
State
Streambed
Area
(sq. ft.) / Avg.
Width (ft.)
Federal
Feature
Area (sq.
ft.) / Avg.
Width (ft.)
Hydro
Veg
Soils
State
Wetland
(sq. ft.) /
Avg.
Width (ft.)
Federal
Wetland
(sq. ft.) /
Avg. Width
(ft.)
MSHCP
Riverine
(sq. ft.) /
Avg. Width (ft.)
MSHCP
Riparian
(sq. ft.) /
Avg. Width (ft.)
1 33.652423
R6 Riverine 1,128 6,842 /
11.9 1,290 /
3 X X 15,916 /
28.73 ----- 6,842 /
11.9 15,916 /
28.73 -117.19284
1b
33.654232
R6 Riverine 358 1,797 /
9.6 716 /
2 X X 2,751/
16.2 ----- 1,797 /
9.6 2,751/
16.2 -117.19348
2 33.65357
R6 Riverine 1,042 8,275 /
16.6 1,806 /
3 X X 20,913 /
38.4 ----- 8,275 /
16. 20,913 /
38.4 -117.19258
3 33.651763
N/A N/A ---- ----- ----- ----- ----- ----- -----
-117.1909
4 33.648827
R6 Riverine 188 1,289 /
12.5 325 /
2.5 X X 871 /
10.25 ----- 1,289 /
12.5 871 /
10.25 -117.18092
5 33.648654
R6 Riverine 130 611 /
4.7 260 /
2 X ---- ---- 611 /
4.7 ----
-117.18552
TOTAL 2,846 18,814
(0.43 acre)
4,397
(0.10 acre)
40,451
(0.93
acres)
----- 18,814
(0.43 acre)
40,451
(0.93 acres)
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 38
Table 3. Summary of impacts.
Feature
Total Impacted [sq. ft (acres)]
State Streambed /
MSHCP Riverine
State Wetland /
MSHCP Riparian Federal Waters Federal Wetland
1 5498 1824 0 0
1b 1797 2751 716 0
2 346 256 0 0
3 0 0 0 0
4 (offsite) 1289 871 325 0
5 (offsite) 611 0 260 0
TOTALS* 9,541 (0.219 ac) 5,702 (0.131 ac) 1,301 (0.03 ac) 0
Table 4. Areas to be incorporated into Compatible Use Area.
Feature
Total Incorporated into the Avoidance/Compatible Use Area [sq. ft (acres)] State Streambed /
MSHCP Riverine
State Wetland /
MSHCP Riparian Federal Waters Federal Wetland
1 1344 14,092 1290 0
1b 0 0 0 0
2 7929 20,657 1806 0
3 0 0 0 0
4 (offsite) 0 0 0 0
5 (offsite) 0 0 0 0
TOTALS* 9,273 (0.21 ac) 34,749 (0.80 ac) 3,096 (0.07 ac) 0
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 39
Figure 9
Photograph Locations
(Photo obtained from Google Earth, 3-9-2011)
Golden Meadows, TT 31194
City of Menifee, California
L&L Environmental, Inc.
BIOLOGICAL AND CULTURAL
INVESTIGATIONS AND MONITORING
RLCC-03-187
March 2022
1 1b
2 3
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 40
Table 5. Photographs of features (December 14, 2011).
Data Point /
GPS Location
(WGS 84)
North West South East Comments
Feature 1 - PP 1
33.655946°
-117.194387°
PP 2
33.655420°
-117.193964°
PP 3
33.655025°
-117.193915°
North – patch of
mulefat present
PP 4
33.654590°
-117.193731°
South - tamarisk
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 41
Data Point /
GPS Location
(WGS 84)
North West South East Comments
PP 5
33.654335°
-117.193251°
South – willows begin
PP 6
33.653907°
-117.192852°
PP 7
33.653740°
-117.192704°
North – mulefat and
willows mix
South – mulefat and
willows mix
PP 8
33.653480°
-117.192530°
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 42
Data Point /
GPS Location
(WGS 84)
North West South East Comments
PP 9
33.653230°
-117.192437°
East - mulefat
Feature 1b –
PP 11
33.652246°
-117.191637°
South – group of
willows
PP 12
33.651649°
-117.190779°
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 43
Data Point /
GPS Location
(WGS 84)
North West South East Comments
Feature 2 - PP 1
33.651927°
-117.193294°
North - willows
PP 2
33.652347°
-117.192941°
PP 3
33.652741°
-117.192733°
North – some
eucalyptus
South - mulefat
PP 4
33.653259°
-117.192854°
North – willow and
cottonwood
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 44
Data Point /
GPS Location
(WGS 84)
North West South East Comments
PP 5
33.653540°
-117.192882°
PP 6
33.653926°
-117.193140°
PP 7
33.654155°
-117.193459°
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 L&L 45
Data Point /
GPS Location
(WGS 84)
North West South East Comments
Feature 3 - PP 8
33.654344°
-117.193689°
PP 9
33.654484°
-117.194388°
West – all signs of
feature end
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 46 L&L
APPENDIX B
Site Photographs
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 47 L&L
(0004) Wheat field 03.28.2017
(3902) Trees along riparian area (background)
within the open field 05.14.2019
(895) Trees in riparian area (from L&L 2013)
(0025) Wheat field 03.28.2017
(3892) Trees along riparian area within the
open field 05.14.2019
Potential raptor nest in eucalyptus tree within
riparian area (from L&L 2013)
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 48 L&L
(0033) California buckwheat scrub 03.28.17
(0056) “Island” of California buckwheat scrub
within wheat field 03.28.2017
(0022) Chaparral (foreground) open field
beyond 12.19.2020
(0042) California buckwheat scrub with wheat
field to the right 03.28.2017
(0058) “Island” of California buckwheat scrub
(foreground) within wheat field, hills with
buckwheat scrub in background
(0023) Chaparral (foreground) open field
beyond 12.19.2020
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 49 L&L
2018 Jurisdictional Area Photographs
February 7, 2018
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 50 L&L
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 51 L&L
Additional Photos of Feature 1b
View of south end of Feature 1b from the southwest, looking northeast, showing the terrain to the south (02.07.2019).
View of west side of Feature 1b, looking northeast, showing the terrain to the west (02.07.2019)
View of east side of Feature 1b, looking northeast, showing the terrain to the east (02.07.2019).
View of the north end of Feature 1b, looking northeast, showing the terrain to the north (02.07.2019).
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 52 L&L
APPENDIX C
List of plant and wildlife species identified on the Golden Meadows site.
Plants [N=115]
Scientific Name Common Name
VASCULAR PLANTS
Dicotyledons
ADOXACEAE MUSKROOT FAMILY
Sambucus nigra ssp. cerulea
(S. mexicana) Mexican elderberry, blue elderberry
AMARANTHACEAE AMARANTH FAMILY
* Amaranthus albus
Tumbleweed, tumbling pigweed
ANACARDIACEAE SUMAC or CASHEW FAMILY
* Schinus molle Peruvian pepper tree
APIACEAE CELERY FAMILY
Daucus pusillus Rattlesnake weed, wild carrot
ASTERACEAE ASTER FAMILY
Acourtia microcephala
(Perezia microcephala) Scapellote, perezia
Ambrosia acanthicarpa
Annual bur-sage, annual sandbur
* Anthemis cotula Mayweed, dog mayweed
Artemisia californica
California sagebrush
Baccharis salicifolia (B.
glutinosa)
Mulefat
Bebbia juncea Sweetbush
* Centaurea melitensis Tocalote
Chaenactis artemisiifolia White pincushion, wormwood pincushion Corethrogyne filaginifolia var.
filaginifolia
(Lessingia filaginifolia)
California-aster, sand-aster
Deinandra fasciculata
(Hemizonia fasciculata) Fascicled tarplant, slender tarweed Encelia farinosa Brittlebush
Erigeron canadensis
(Conyza canadensis)
Horseweed, mare's tail
Eriophyllum confertiflorum Golden-yarrow
Eriophyllum multicaule Many-stem woolly daisy
Gutierrezia californica (G.
bracteata) California matchweed
Helianthus annuus
Western sunflower
* Lactuca serriola
Prickly lettuce
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 53 L&L
Scientific Name Common Name
Lasthenia californica
(L. chrysostoma) California goldfields
Layia platyglossa Tidy-tips
Logfia filaginoides
(Filago californica) California filago
*
Matricaria discoidea
(Chamomilla suaveolens,
M. matricarioides) Pineapple weed
Rafinesquia californica
California chicory
* Senecio vulgaris Common groundsel
* Sonchus oleraceus
Common sow thistle
Stephanomeria virgata Wreath plant
Stylocline gnaphaloides
Everlasting neststraw
Tetradymia comosa Hairy horsebrush, common-thorn
Uropappus lindleyi
(Microseris lindleyi, M.
linearifolia) Silverpuffs
*? Xanthium spinosum Spiny cocklebur
BORAGINACEAE BORAGE OR WATERLEAF FAMILY
Amsinckia intermedia
(A. menziesii var. intermedia) Large flower rancher's fiddleneck Cryptantha intermedia
Common cryptantha
Heliotropium curassavicum Wild heliotrope
Pectocarya linearis Slender pectocarya
Phacelia minor
Wild Canterbury bells
Phacelia ramosissima Branching phacelia
Plagiobothrys sp.
Popcornflower
BRASSICACEAE MUSTARD FAMILY
* Brassica nigra Black mustard
* Hirschfeldia incana
(Brassica geniculata)
Shortpod mustard
Lepidium nitidum Shining peppergrass
* Raphanus sativus Wild radish
* Sisymbrium irio
London rocket
* Sisymbrium orientale Wild mustard, hare's ear cabbage Thysanocarpus curvipes Lacepod
CACTACEAE CACTUS FAMILY
Cylindropuntia californica var.
parkeri (Opuntia parryi) Valley cholla
CHENOPODIACEAE GOOSEFOOT FAMILY
* Chenopodium murale Nettle-leaved goosefoot, lamb's quarters * Salsola tragus
Russian thistle
CONVOLVULACEAE MORNING-GLORY FAMILY
Calystegia macrostegia Morning-glory
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 54 L&L
Scientific Name Common Name
Cuscuta californica Chaparral dodder, witch's hair
CRASSULACEAE STONECROP FAMILY
Crassula connata (C. erecta) Pygmy-weed, pygmy stonecrop
CUCURBITACEAE GOURD FAMILY, CUCUMBER FAMILY
Cucurbita foetidissima
Calabazilla
Marah macrocarpa
Chilicothe, wild cucumber
EUPHORBIACEAE SPURGE FAMILY
Croton setiger (C. setigerus,
Eremocarpus setiger, E.
setigerus)
Turkey-mullein, doveweed
Euphorbia albomarginata
(Chamaesyce
albomarginata)
Rattlesnake sandmat, rattlesnake weed
FABACEAE LEGUME FAMILY, PEA FAMILY
Acmispon americanus
(Lotus purshianus, L.
unifoliatus) "Spanish" clover
Acmispon glaber
(Lotus scoparius) Deerweed
Lupinus sp. Unid. lupine
Lupinus bicolor Miniature lupine, dove lupine
* Medicago polymorpha California burclover
* Vicia villosa Winter vetch
GERANIACEAE GERANIUM FAMILY
* Erodium botrys Long-beak filaree
* Erodium cicutarium
Redstem filaree
LAMIACEAE MINT FAMILY
* Marrubium vulgare
Horehound
Salvia apiana
White sage
Salvia columbariae
Chia
Salvia mellifera Black sage
Trichostema lanceolatum Vinegar weed
MALVACEAE MALLOW FAMILY
* Malva parviflora
Cheeseweed
MYRSINACEAE MYRSINE FAMILY
* Anagallis arvensis Scarlet pimpernel
MYRTACEAE MYRTLE FAMILY, EUCALYPTUS FAMILY
* Eucalyptus sp.
Ornamental eucalyptus
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 55 L&L
Scientific Name Common Name
NYCTAGINACEAE FOUR O'CLOCK FAMILY
Mirabilis laevis var. crassifolia
(M. californica) Wishbone bush
ONAGRACEAE EVENING-PRIMROSE FAMILY
Camissonia sp.
Unid. evening-primrose
Eulobus californica
(Camissonia
californica)
California false mustard, mustard evening primrose
PAPAVERACEAE POPPY FAMILY
Eschscholzia californica California poppy
PHRYMACEAE LOPSEED FAMILY
Mimulus aurantiacus
(M. puniceus, M. longiflorus) Bush monkeyflower,sticky monkeyflower Mimulus guttatus Seep monkeyflower
PLANTAGINACEAE PLANTAIN FAMILY
Antirrhinum nuttallianum Nuttall snapdragon, violet snapdragon Keckiella antirrhinoides Yellow bush-penstemon
Plantago erecta California plantain
POLEMONIACEAE PHLOX FAMILY
Eriastrum sapphirinum
Sapphire woollystar
Navarretia hamata Hooked navarretia
POLYGONACEAE BUCKWHEAT FAMILY
Chorizanthe fimbriata Fringed spineflower
**
Chorizanthe polygonoides var.
longispina Long-spined spineflower
Eriogonum fasciculatum
var. foliolosum
Leafy California wild buckwheat, interior California
buckwheat
Eriogonum fasciculatum
var. polifolium
Mojave Desert California buckwheat
*
Polygonum aviculare ssp.
depressum (P. arenastrum) Common knotweed
* Rumex crispus Curly dock
ROSACEAE ROSE FAMILY
Adenostoma fasciculatum Chamise
RUBIACEAE MADDER FAMILY, COFFEE FAMILY
*? Galium aparine Goose grass, annual bedstraw
SALICACEAE WILLOW FAMILY
Populus fremontii ssp.
fremontii
Fremont cottonwood
Salix lasiolepis Arroyo willow
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 56 L&L
Scientific Name Common Name
SCROPHULARIACEAE FIGWORT FAMILY, SNAPDRAGON FAMILY
Scrophularia californica California figwort, coast figwort
SOLANACEAE NIGHTSHADE FAMILY
Datura wrightii (D. meteloides)
Jimsonweed, tolguacha
* Nicotiana glauca
Tree tobacco
*?
Solanum americanum
(S. nodiflorum) White nightshade
TAMARICACEAE TAMARISK FAMILY
* Tamarix species
Tamarisk
URTICACEAE NETTLE FAMILY
* Urtica urens Dwarf nettle
ZYGOPHYLLACEAE CALTROP FAMILY
* Tribulus terrestris
Puncture vine
Monocotyledons
AGAVACEAE CENTURY PLANT FAMILY, AGAVE FAMILY
Hesperoyucca whipplei
(Yucca whipplei)
Chaparral yucca
LILIACEAE LILY FAMILY
Calochortus splendens Splendid mariposa lily
POACEAE GRASS FAMILY
* Avena barbata Slender wild oat
* Avena fatua Wild oat
* Bromus species Non-native brome
* Bromus diandrus (B. rigidus) Ripgut brome
* Bromus madritensis ssp.
rubens (B. rubens)
Red brome
* Hordeum murinum Wall barley, hare barley
* Lamarckia aurea Goldentop grass
* Phalaris species Unid. canary grass
* Schismus barbatus Mediterranean schismus
* Triticum aestivum Common wheat (cultivated)
THEMIDACEAE BRODIAEA FAMILY
Dichelostemma capitatum
(D. pulchella, Brodiaea
pulchella)
Blue dicks, wild hyacinth
Muilla maratima Common muilla
* non-native species ** special status species
Wildlife [N=54]
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 57 L&L
Scientific Name Common Name
VERTEBRATES
Reptiles [N=3]
Iguanidae Iguanid Lizards
Sceloporus orcutti Granite spiny lizard
Uta stansburiana Side-blotched lizard
Phrynosomatidae Spiny Lizards
** Phrynosoma blainvillii Coast horned lizard
Birds [N=45]
Accipitridae Hawks, Eagles, and Harriers
** Accipiter cooperii Cooper’s hawk
Buteo jamaicensis Red-tailed hawk
** Circus cyaneus Northern harrier
** Elanus leucurus White-tailed kite (fly over)
Aegithalidae Long-tailed Tits
Psaltriparus minimus Bushtit
Alaudidae Larks
** Eremophila alpestris actia California horned lark
Ardeidae Herons
** Ardea herodias Great blue heron (fly over)
Cathartidae Vultures
Cathartes aura Turkey vulture
Charadriidae Plovers
Charadrius vociferus Killdeer
Columbidae Pigeons and Doves
* Columba livia Rock dove, common pigeon
Zenaida macroura Mourning dove
Corvidae Crows and Jays
Aphelocoma californica California scrub jay
Corvus brachyrhynchos American crow
Corvus corax Common raven
Cuculidae Cuckoos
Geococcyx californianus Greater roadrunner
Emberizidae Emberizine Sparrows
Amphispiza belli Sage sparrow
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 58 L&L
Scientific Name Common Name
Melospiza melodia Song sparrow
Pipilo crissalis senicula California towhee
Zonotrichia leucophrys White-crowned sparrow
Falconidae Falcons
Falco sparverius American kestrel
Fringillidae Finches
Carduelis psaltria Lesser goldfinch
Haemorhous (Carpodacus)
mexicanus House finch
Hirundinidae Swallows
Stelgidopteryx serripennis Northern rough-winged swallow
Icteridae Icterids
Agelaius phoeniceus Red-winged blackbird
Euphagus cyanocephalus Brewer's blackbird
Icterus bullockii Bullock's oriole
Sturnella neglecta Western meadowlark
Mimidae Mockingbirds
Mimus polyglottos polyglottos Northern mockingbird
Toxostoma redivivum California thrasher
Odontophoridae Quail
Callipepla californica californica California quail
Parulidae Wood Warblers
Dendroica coronata Yellow-rumped warbler
Picidae Woodpeckers
Colaptes auratus Northern flicker
Picoides nuttallii Nuttall's woodpecker
Polioptilidae Gnatcatchers
Polioptila caerulea Blue-gray gnatcatcher
** Polioptila californica californica Coastal California gnatcatcher
Sturnidae Starlings
* Sturnus vulgaris European starling
Timaliidae Babblers
Chamaea fasciata Wrentit
Trochilidae Hummingbirds
Calypte anna Anna's hummingbird
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 59 L&L
Scientific Name Common Name
** Calypte costae Costa's hummingbird
Troglodytidae Wrens
Catherpes mexicanus Canyon wren
Thryomanes bewickii Bewick's wren
Turdidae Thrushes
Sialia mexicana Western bluebird
Tyrannidae Tyrant Flycatchers
Sayornis nigricans Black phoebe
Sayornis saya Say's phoebe
Tyrannus verticalis Western kingbird
Mammals [N=6]
Canidae Dogs, Foxes, and Coyotes
* Canis domesticus Domestic dog
Canis latrans Coyote
Geomyidae Pocket Gophers
Thomomys bottae Botta's pocket gopher (sign)
Leporidae Rabbits
** Lepus californicus bennettii Black-tailed jackrabbit Sylvilagus audubonii Audubon's cottontail
Sciuridae Squirrels
Spermophilus beecheyi California ground squirrel
* non-native species
** special status species
Wildlife species list excludes invertebrates.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 60 L&L
APPENDIX D
Certification
Certification: I hereby certify that the statements furnished above and in the attached exhibits present the data and i nformation required for this biological evaluation, and that the fac ts, statements, and informatio n presented are true and correct to the best of my knowledge and belief.
DATE: _March 22, 2022_ SIGNED: __________________________________________ Leslie Irish, Principal, L&L Environmental, Inc.
909-335-9897
1) Fieldwork Performed By: 2) Fieldwork Performed By:
Leslie Irish
Name Name
3) Fieldwork Performed By: 4) Fieldwork Performed By:
Name Name
5) Fieldwork Performed By: 6) Fieldwork Performed By:
Name Name
Check here if adding any additional names / signatures below or on other side of page.
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 61 L&L
BIOLOGICAL REPORT SUMMARY SHEET
Applicant Name: _Richland Communities______________________________________ Assessor’s Parcel Number(s): __360-300-002, -003, -004, -005, -006, -009, 360-350-001 Section, Township and Range: ___Sections 15 and 16, Township 6 South, Range 3 West Building and Safety Log Number: ____________________________________________ Case Number: _TR 31194___________ Lot/Parcel _________ EA Number _________
MARK ITEM(S)
SURVEYED FOR
SPECIES or ENVIRONMENTAL ISSUE of
CONCERN
(Mark Yes, No, or N/A
regarding species findings on
the referenced site)
Yes No n/a
Arroyo Southwestern Toad Yes No n/a
X Blueline Stream(s) Yes No n/a
X Burrowing Owl (previous surveys) Yes No n/a
Coachella Valley Fringed-toed Lizard Yes No n/a
X Coastal California Gnatcatcher (previous surveys) Yes No n/a X Coastal Sage Scrub (previous surveys) Yes No n/a
Delhi Sands Flower-loving Fly Yes No n/a
Desert Pupfish Yes No n/a
Desert Slender Salamander Yes No n/a
Desert Tortoise Yes No n/a
Flat-tailed Horned Lizard Yes No n/a
Least Bell’s Vireo Yes No n/a
X Oak Woodlands (previous surveys) Yes No n/a
Quino Checkerspot Butterfly Yes No n/a
Riverside Fairy Shrimp Yes No n/a
Santa Ana River Woolystar Yes No n/a
San Bernardino Kangaroo Rat Yes No n/a
Slender-horned Spineflower Yes No n/a
Stephens’ Kangaroo Rat Yes No n/a
X Vernal Pools Yes No n/a
X Wetlands Yes No n/a
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 62 L&L
MARK ITEM(S)
SURVEYED FOR
SPECIES or ENVIRONMENTAL ISSUE of
CONCERN
(Mark Yes, No, or N/A
regarding species findings on
the referenced site)
X Cooper’s Hawk (previous surveys) Yes No n/a
X California Horned Lark (previous surveys) Yes No n/a
X Black-tailed Jackrabbit (previous surveys) Yes No n/a X Coastal California Gnatcatcher (previous surveys) Yes No n/a X White-tailed Kite (previous surveys) Yes No n/a
Other Yes No n/a
Species of concern s hall be any unique, rare, endangered, or threatened species. It shall include species used to delineate wetlands and riparian corridors. It shall also in clude any host s, perching, or food plants used by any animals listed as r are, endangered, threatened, or candidate species by either state, or federal regulations, or for Riverside County as listed by the California Department of Fish and Wildlife Natural Diversity Data Base (CNDDB).
I declare under penalty of perjury that th e information provided on th is summary s heet is in accordance with the information provided in the biological report or habitat assessment.
_____________________L & L Environmental, Inc. March 22, 2022 ________ Signature and Company Name Date
___________________________________________ _________________________ 10(a) Permit Number (if applicable) Permit Expiration Date
County Use Only
Received By: _________________________________________ Date: ____________________ PD-B# ______________________________________________
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 63 L&L
Attachment E-4
LEVEL OF SIGNIFICANCE CHECKLIST
For Biological Resources
(Submit two copies to the County)
Case Number: _TR 31194___ Lot/Parcel No. _____________ EA Number _________ Assessor's Parcel Number(s): 360-300-002, -003, -004, -005, -006, -009, 360-350-001 Date: _June 20, 2019_
Biological Resources: (Check the level of impact that applies to the following questions.)
Potentially Less than Significant Less than No
Significant Impact with Mitigation Significant Impact
Impact Incorporated Impact
a) Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Conservation Community Plan, or other approved local, regional, or state conservation plan?
b) Have a substantial adverse effect, either directly or through habitat modifications, on any endangered, or threatened species, as listed in Title 14 of the California Code of Regulations (Sections 670.2 or 670.5) or in Title 50, Code of Federal Regulations (Sections 17.11 or 17.12)?
c) Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Wildlife, or U. S. Wildlife Service?
d) Interfere substantially with the movement of any native resident or migratory fish or wildlife species, or with established native resident migratory wildlife corridors, or impede the use of native wildlife nursery sites?
Updated Jurisdictional Delineation
TR 31194, Golden Meadows (Menifee Assemblage), Menifee, California March 2022 RLCC-03-R187.JD4 64 L&L
LEVEL OF SIGNIFICANCE CHECKLIST
For Biological Resources
(Submit two copies to the County)
e) Have a substantial adverse effect on any riparian habitat, or other sensitive natural community identified in local or regional plans, policies, regulations, or by the California Department of Fish and Wildlife, or the U.S. Fish and Wildlife Service?
f) Have a substantial adverse effect on federally protected wetlands, as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pools, coastal, etc.) through direct removal, filling, hydrological interruption)
g) Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance?
Findings of Fact:
A mapped blueline stream is present onsite and associated with riparian/riverine vegetation.
Six (6) special status species have been identified onsite during past and present surveys (burrowing owl, coastal California gnatcatcher, Cooper’s hawk, white-tailed kite, California horned lark, and black-tailed jackrabbit).
Potential nesting habitat for burrowing owl and other bird species protected by the migratory bird treaty act is present onsite.
Proposed Mitigation:
Avoidance and/or onsite or offsite restoration of riparian habitat is recommended.
Preconstruction surveys for burrowing owl and other nesting bird species are recommended prior to disturbance of the site.
Monitoring Recommended:
Source: CGP Fig. VI.36-VI.40
Revised October 1999
This page intentionally left blank.
Appendix D. Cultural Resources Assessment and
Paleontological Resources
Assessment
CONFIDENTIAL -
CONTACT CITY STAFF
Appendix E. Hydrology Analysis Report
Preliminary Hydrology Analysis
Tract Map No. 31194
Golden Meadows – Phase 4
Major Modification
Prepared for
Richland Communities, Inc.
November 2021
Hunsaker &
Associates
PreliminaryHydrologyAnalysis
TractMapNo.31194
GoldenMeadows–Phase4
MajorModification
November2021Hunsaker&
Associates
H:\00546\Planning\Drainage\Parts\00546-Preliminary Hydrology - Section 1 Report - 2021-11-08.docx W.O. # 3763- 3194
PRELIMINARY HYDROLOGY ANALYSIS
FOR THE MAJOR MODIFICATION OF THE
“G OLDEN MEADOWS” DEVELOPMENT
TRACT 31194
PREPARED FOR
RICHLAND COMMUNITIES, INC.
23121 ANTONIO PARKWAY
RANCHO SANTA MARGARITA, CA 92688
PHONE NUMBER: (949) 858-4980
RIVERSIDE COUNTY FLOOD CONTROL DISTRICT
COUNTY OF RIVERSIDE, CALIFORNIA
PREPARED BY:
2900 ADAMS STREET; SUITE A-15
RIVERSIDE CA, 92504
PHONE NUMBER: (951) 352-7200
________________________________________________________ PREPARED UNDER THE SUPERVISION OFBRIAN R. LOWELL, R.C.E. 74550 MAY 2021
REVISION: NOVEMBER 2021
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification Page ii
Table of Contents
Section 1 – Introduction ________________________________________________________ 1-1 Project Description __________________________________________________________ 1-1 Pre-Developed Condition _____________________________________________________ 1-1 Post-Developed Condition ____________________________________________________ 1-2 Analysis ___________________________________________________________________ 1-3 Conclusion _________________________________________________________________ 1-4 Section 2 – Riverside County Flood Division Data __________________________________ 2-1 Hydrologic Soils Group Map __________________________________________________ 2-2 Precipitation Intensity Data ___________________________________________________ 2-4 Section 3 – Hydrology Calculations
Area ‘A’ Analysis ____________________________________________________ Area ‘A’ - 3-1 Area ‘C’ Analysis ____________________________________________________ Area ‘C’ - 3-1 Area ‘D’ Analysis ____________________________________________________ Area ‘D’ - 3-1 Section 4 – Hydrology Maps ____________________________________________________ 4-1 Existing Conditions Hydrology Map ____________________________________________ 4-2 Proposed Conditions Hydrology Map ___________________________________________ 4-3 Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
SECTION 1 - Project Description
Introduction
The purpose of this report is to present the backup hydrology that will be used for the planning and design of the major modification to the existing ‘Golden Meadows’, tract 31194 p r o j e c t . T h i s r e p o r t a l s o s e r v e s a s t h e b a s i s f o r a n a l y z i n g a n d d e s i g n i n g t h e s t o r m d r a i n , retention systems and earthen channel within the project site.
Project Description
The proposed modification to the approved hydrology analysis for tract 31194 consists of m o d i f y i n g d r a i n a g e m a n a g e m e n t a r e a s ‘ A ’ , ‘ C ’ a n d ‘ D ’ . T h e p r o p o s e d m o d i f i c a t i o n s w i l l increase the residential density and therefore change the hydraulic modeling of the project. This supplemental analysis is intended to provide the backup hydrology calculations to support the proposed modifications to the residential development.
The underlying project known as Tract 31194 “Golden Meadows” consists of 206.8 acres, and proposes the construction of 474 single family homes (103.2 ac.), 7.3 acres of park,
50.0 acres of open space, 2.7 acres of basins and 43.6 acres of paved streets, un-paved trails, and general improvements related to a residential development. The proposed project site is located wi th i n th e S an J a ci n to w a te r s h e d p or ti on S an ta A n a Ri v e r , wi th i n th e Ci ty of M en i f e e , i n th e County of Riverside, California. The project site is bounded by Wickerd Road to the north, Ascot Way to the east, vacant land to the south and Evans Road to the west (see included vicinity map).
Existing Conditions
The site is currently in a natural condition, containing grasses and brush. Topographically, th e s i te i s g en e r al l y h i l l y , wi th a m i l d s l op e t ow a r d th e n or th w i th a t op og r a p h i c r el i ef on th e order of 300 feet. The lowest elevation of approximately 1,500 feet above mean sea level (msl) is located in the northwest corner of the site. The highest elevation of approximately 1,800 feet (msl) is located along the westerly property line. The existing drainage pattern of the m o d i f i c a t i o n a r e a d i v i d e s t h e s i t e i n t o t h r e e d i s t i n c t d r a i n a g e a r e a s , D M A ‘ A ’ , ‘ C ’ a n d ‘ D ’ .
DMA ‘A’ consists of the eastern most portion of the site, approximately 173.2 acres and drains n or th w e s te r l y . D M A ‘ C ’ c on s i s ts of th e w e s te r n m os t p or ti on of th e s i te , a p p r ox i m a tel y 1 8 . 6 a c r e s a n d d r a i n s s o u t h e a s t e r l y . D M A ‘ D ’ c o n s i s t s o f t h e s o u t h p o r t i o n o f t h e s i t e a n d i s approximately 60.0 acres and drains northerly. All three drainage areas generally drain as sheet flow or in small natural gullies directly into natural creeks throughout the site.
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
Proposed Conditions
On-Site
As required by the Riverside Regional Water Quality Control Board (Santa Ana W a t e r s h e d ) , a n d t h e M S 4 P e r m i t ( M u n i c i p a l S e p a r a t e S t o r m S e w e r S y s t e m ) , t h e p r o p o s e d grading of this site has been designed to be consistent with the existing drainage patterns. The proposed development will further subdivide the overall hydrological drainage areas into smaller drainage management areas, designated ‘A’ through ‘L’. The major modification to Tract 31194 will revise the drainage pattern of the proposed condition DMA’A’, ‘C’ and ‘D’. We are limiting our supplemental analysis to these three areas, please refer to the underlying hydrology analysis prepared by Hunsaker & Associates for information and calculations pertaining to the rest of the development. The revised DMA ‘A’ comprises of 95.88 acres and is tributary to water quality and detention basin ‘A’ located in the northwestern most corner of the project. The revised DMA ‘C’ comprises of 14.19 acres and is tributary to water quality and detention basin ‘C’ located in the southeastern most corner of the project. The revised DMA ‘D’ comprises of
54.51 acres and is tributary to water quality and detention ‘D’ located in the center of the project.
The proposed on-site water quality and detention basins are being designed to meet water quality requirements and mitigate for any increase in run-off associated with the development of areas ‘A’, ‘C’ and ‘D’. Furthermore, basins A and C are being designed as ‘Extended Detention Basins’, each which will include a concrete lined forebay, low flow gravel diversion channels, and a sand filter with a metered outlet structure. Please refer to the WQMP and Storm Drain Plans for this project for complete basin design and outlet structure details. Basin D is designed as an infiltration basin, which is sized to capture and infiltrate the water quality volume in its entirety.
The proposed facilities are designed to convey the 100-year storm event, we have analyzed the site based on the pre and post development conditions for the 2-year, 10-year, and 100-year storm events. RCFC&WCD rational and unit hydrograph methodologies were utilized to determine pre and post development flow rates. The results of this analysis are summarized in the following tables.
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
Analysis – Drainage Management Area ‘A’
DMA ‘A’ is comprised of 95.88 acres. The proposed development will increase the peak flow rate and volume of storm water run- off, the largest peak flow rate increase was experienced during the 2 -year 24-hour storm event, where the anticipated flow rate increased by 7.5 cfs, as compared to natural condition. This increase is being mitigated by the proposed extended detention and water quality basin located on the northerly most portion of the site.
DRAINAGE MANAGEMENT AREA ‘A’
UNIT HYDROGRAPH – PEAK FLOW RATE (cfs)
2 YEAR 10 YEAR 100 YEAR
Ex Pro. Routed Ex Pro. Routed Ex Pro. Routed
1 HOUR 108.4 90.4 -18.0 232.9 167.3 -65.6 389.4 274.5 -114.9 3 HOUR 51.6 39.3 -12.3 144.6 89.1 -55.5 256.5 155.7 -100.8 6 HOUR 44.6 34.4 -10.2 140.1 81.9 -58.2 255.6 148.5 -107.1 24 HOUR 4.6 12.1 7.5 44.4 24.8 -19.6 102.6 57.2 -45.4
The largest storm volume incre ase was experienced during the 2 year 24 hour storm event, where the anticipat ed run -off is increased by 4.51 acre feet from the natural condition.
This increase is being mitigated by the proposed extended detention and water quality basin located on the northerly most portion of the site.
DRAINAGE MANAGEMENT AREA ‘A’
UNIT HYDROGRAPH – STORM VOLUME (Ac-Ft)
2 YEAR 10 YEAR 100 YEAR
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
1 HOUR 3.23 2.62 -0.61 9.46 5.25 -4.21 17.46 9.69 -7.77 3 HOUR 2.60 3.31 0.71 10.6 6.50 -4.10 25.00 13.62 -11.38 6 HOUR 2.89 4.53 1.64 12.6 8.99 -3.61 35.67 19.15 -16.52 24 HOUR 2.89 7.40 4.51 13.0 12.3 -0.70 46.32 27.29 -19.03
DRAINAGE MANAGEMENT AREA ‘A’
DEVELOPED CONDITION RATIONAL METHOD SUMMARY
AREA (ac.) TIME OF
CONCENTRATION
%
IMPERVIOUS Q (cfs)
2 YEAR 95.88 ac. 14.85 min. 27.6% 57.4 cfs
10 YEAR 95.88 ac. 13.66 min. 27.6% 114.8 cfs
100 YEAR 95.88 ac. 12.98 min. 27.6% 192.3 cfs
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
Drainage Management Area ‘C’
DMA ‘C’ is comprised of 14.19 acres. The proposed development will increase the peak flow rate and volume of storm water run -off, the largest peak flow rate increase was experienced during the 2- year 1-hour storm event, where the anticipated flow rate increased by 2.8 cfs, as compared to natural condition. This increase is being mitigated by the proposed e xtended detention and water quality basin located on the northerly most portion of the site.
DRAINAGE MANAGEMENT AREA ‘C’
UNIT HYDROGRAPH – PEAK FLOW RATE (cfs)
2 YEAR 10 YEAR 100 YEAR
Ex Pro. Routed Ex Pro. Routed Ex Pro. Routed
1 HOUR 14.7 17.5 2.8 31.2 31.8 0.6 51.9 51.5 -0.4
3 HOUR 6.0 6.5 0.5 17.4 14.6 -2.8 30.9 25.4 -5.5
6 HOUR 5.1 5.9 0.8 16.9 14.4 -2.5 31.0 25.5 -5.5
24 HOUR 0.5 1.8 1.3 4.4 3.5 -0.9 10.9 8.3 -2.6
The largest storm volume increase was experienced during the 2 year 24 hour storm event, where the anticipated run -off is increased by 0.76 acre feet from the natural condition.
This increase is being mitigated by the proposed sand filter basin located on the southeasterly most portion of the site.
DRAINAGE MANAGEMENT AREA ‘C’
UNIT HYDROGRAPH – STORM VOLUME (Ac-Ft)
2 YEAR 10 YEAR 100 YEAR
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
1 HOUR 0.32 0.38 0.06 0.96 0.74 -0.22 1.84 1.39 -0.45
3 HOUR 0.25 0.47 0.22 0.99 0.92 -0.07 2.57 1.94 -0.63
6 HOUR 0.28 0.65 0.37 1.21 1.28 0.07 3.60 2.72 -0.88
24 HOUR 0.31 1.07 0.76 1.12 1.76 0.64 4.48 3.87 -0.61
DRAINAGE MANAGEMENT AREA ‘C’
DEVELOPED CONDITION RATIONAL METHOD SUMMARY
AREA (ac.) TIME OF
CONCENTRATION
%
IMPERVIOUS Q (cfs)
2 YEAR 14.19 ac. 10.38 min. 29.2 % 11.3 cfs
10 YEAR 14.19 ac. 10.25 min. 29.2 % 20.1 cfs
100 YEAR 14.19 ac. 10.17 min. 29.2 % 36.9 cfs
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
Drainage Management Area ‘D’
DMA ‘D’ is comprised of 54.51 acres. The proposed development will increase the peak flow rate and volume of storm water run- off, the largest peak flow rate increase was experienced during the 2-year 3-hour storm event, where the anticipated flow rate increased by 9.8 cfs, as compared to natural condition. This increase is being mitigated by the proposed extended detention and water quality basin located on the northerly most portion of the site.
DRAINAGE MANAGEMENT AREA ‘D’
UNIT HYDROGRAPH – PEAK FLOW RATE (cfs)
2 YEAR 10 YEAR 100 YEAR
Ex Pro. Routed Ex Pro. Routed Ex Pro. Routed
1 HOUR 45.0 54.0 9.0 97.0 98.4 1.4 166.5 161.5 -5.0
3 HOUR 13.2 23.0 9.8 48.0 50.9 2.9 92.1 89.4 -2.7
6 HOUR 10.7 19.8 9.1 43.8 47.6 3.8 88.0 86.4 -1.6
24 HOUR 1.6 7.6 6.0 9.6 13.8 4.2 32.3 32.3 0.0
The largest storm volume increase was experienced during the 10 year 24 hour storm event, where the anticipated run -off is increased by 5.26 acre feet from the natural condition.
This increase is being mitigated by the proposed infiltration basin located on the easterly most portion of the drainage management area.
DRAINAGE MANAGEMENT AREA ‘D’
UNIT HYDROGRAPH – STORM VOLUME (Ac-Ft)
2 YEAR 10 YEAR 100 YEAR
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
Ex Pro.
Mitigation
Volume
1 HOUR 0.90 1.56 0.66 2.69 2.97 0.28 5.68 5.50 -0.18
3 HOUR 0.64 2.03 1.39 2.49 3.77 1.28 7.56 7.66 0.10
6 HOUR 0.73 2.82 2.09 3.06 5.27 2.21 10.16 10.74 0.58
24 HOUR 1.00 4.65 3.65 2.32 7.58 5.26 12.13 15.59 3.46
DRAINAGE MANAGEMENT AREA ‘D’
DEVELOPED CONDITION RATIONAL METHOD SUMMARY
AREA (ac.) TIME OF
CONCENTRATION
%
IMPERVIOUS Q (cfs)
2 YEAR 54.51 ac. 19.12 min. 45.0 % 36.3 cfs
10 YEAR 54.51 ac. 18.19 min. 45.0 % 71.1 cfs
100 YEAR 54.51 ac. 17.56 min. 45.0 % 122.1 cfs
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 1
Methodology
This hydrology report is to be used only to analyze flow to, through, and out of the site using the Riverside County Rational Method. In regard to pipe sizing, the hydrology programs were utilized only as a tool for obtaining preliminary sizing of the storm drain facilities by allowing the program to determine minimum pipe sizes. The actual storm drain system and pipe sizes shall be designed per Riverside County Flood Control District criteria. Civil Design Version 7.0 Computer Software Program and AES Engineering Software 2011 version were used in generating the hydrological and hydraulic analysis for this report.
Conclusion
The development of this project does not propose a significant change over the existing conditions as illustrated in the previous tables. Peak flow rates however, did increase as would be expected with the addition of impervious area. This increase in flow rate and any increase in run-off volume will be mitigated by the proposed detention and water quality basins throughout the site.
Based upon the results of this report, it is concluded that drainage facilities discussed above will adequately protect the site area from flood damage associated with the 100-year storm e v e n t . T h e p r o p o s e d f a c i l i t i e s , w i t h u l t i m a t e d e v e l o p m e n t a n d a d e q u a t e m a i n t e n a n c e , w i l l convey flows safely through the site area in accordance with Riverside County requirements.
NOT TO SCALE
HUNSAKER & ASSOCIATESINLAND EMPIRE REGIONIRVINE, INCFIGURE 1: VICINITY MAPHUNSAKERENWS THOMAS BROTHERS MAPS:PAGE 868, GRID B-6, B-7, C-6, C-7, D-6 & D-7
INDEX MAP
HUNSAKERENWSHUNSAKER & ASSOCIATESINLAND EMPIRE REGIONIRVINE, INCFIGURE 2: AERIAL PHOTOGRAPH
PROJECTSITE
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 2
SECTION 2 - Riverside County Flood Control Data
Hydrologic Soils Group Map
Precipitation Intensity Data
PROJECTSITE
PROJECTSITE
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/10/2018
3723100 3723300 3723500 3723700 3723900 3724100
3723100 3723300 3723500 3723700 3723900 3724100
481300 481500 481700 481900 482100 482300 482500 482700 482900 481300 481500 481700 481900 482100 482300 482500 482700 482900 33° 39' 28'' N
117° 12' 9'' W
33° 39' 28'' N
117° 10' 57'' W
33° 38' 49'' N
117° 12' 9'' W
33° 38' 49'' N
117° 10' 57'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 400 800 1600 2400
Feet
0 100 200 400 600
Meters
Map Scale: 1:8,490 if printed on A landscape (11" x 8.5") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:15,800.
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 map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.
Soil Survey Area: Western Riverside Area, California
Survey Area Data: Version 11, Sep 12, 2018
Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.
Date(s) aerial images were photographed: Feb 24, 2015—Feb 26, 2015
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—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/10/2018
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CaC2 Cajalco fine sandy loam,
2 to 8 percent slopes,
eroded
C 7.5 3.3%
CaD2 Cajalco fine sandy loam,
8 to 15 percent
slopes, eroded
C 7.3 3.3%
CbD2 Cajalco rocky fine sandy
loam, 5 to 15 percent
slopes, eroded
D 0.6 0.3%
CbF2 Cajalco rocky fine sandy
loam, 15 to 50 percent
slopes, eroded
D 13.6 6.1%
CkD2 Cieneba rocky sandy
loam, 8 to 15 percent
slopes, eroded
D 2.5 1.1%
GtA Grangeville fine sandy
loam, drained, 0 to 2
percent sl opes
A/D 0.2 0.1%
HcD2 Hanford coarse sandy
loam, 8 to 15 percent
slopes, eroded
A 2.8 1.2%
HnC Honcut sandy loam, 2 to
8 percent slopes
A 13.6 6.1%
HnD2 Honcut sandy loam, 8 to
15 percent slopes,
eroded
A 7.6 3.4%
LaC Las Posas loam, 2 to 8
percent slopes
D 0.2 0.1%
LaD2 Las Posas loam, 8 to 15
percent slopes,
eroded
D 6.7 3.0%
LkD2 Las Posas rocky loam, 8
to 15 percent slopes,
eroded
D 3.8 1.7%
LkF3 Las Posas rocky loam,
15 to 50 percent
slopes, severely
eroded
D 0.4 0.2%
PsC Porterville clay,
moderately deep, 2 to
8 percent slopes
D 4.8 2.2%
VeC2 Vallecitos loam, thick
solum variant, 2 to 8
percent slopes,
eroded
C 9.1 4.1%
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/10/2018
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI WyC2 Wyman loam, 2 to 8
percent slopes,
eroded
C 79.8 35.7%
YbC Yokohl loam, 2 to 8
percent slopes
D 57.0 25.5%
YbE3 Yokohl loam, 8 to 25
percent slopes,
severely eroded
D 5.9 2.6%
Totals for Area of Interest 223.4 100.0%
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
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/10/2018
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
10/10/2018
PROJECT SITE
SAN JACINTO
RIVER BASIN
PROJECT SITE
SLOPE=0.53
PROJECT SITE
INTENSITY = 0.55
PROJECT SITE
INTENSITY = 1.3
PROJECT SITE
INTENSITY = 0.85
PROJECT SITE
INTENSITY = 2.0
PROJECT SITE
INTENSITY = 1.2
PROJECT SITE
INTENSITY = 3.0
PROJECT SITE
INTENSITY = 2.0
PROJECT SITE
INTENSITY = 5.0
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
SECTION 3 – Hydrology Calculations
· Rational Hydrology Analysis
· Unit-Hydrograph Analysis
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Area A
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
· Area ‘A’ – 2 Year Pre-Development Condition – Rational Method Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Riverside County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 02/08/19 File:EXA002.out ------------------------------------------------------------------------ TRACT 31194 - 'GOLDEN MEADOWS' HYDROLOGY STUDY – AREA ‘A’ EXISTING CONDITION RATIONAL METHOD - 2 YEAR STORM
HUNSAKER & ASSOCIATES, FEBRUARY 2019
BY: BRIAN LOWELL, PE
------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file
------------------------------------------------------------------------ Program License Serial Number 6407
------------------------------------------------------------------------ Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District 1978 hydrology manual
Storm event (year) = 2.00 Antecedent Moisture Condition = 1 2 year, 1 hour precipitation = 0.550(In.)
100 year, 1 hour precipitation = 1.300(In.)
Storm event year = 2.0
Calculated rainfall intensity data:
1 hour intensity = 0.550(In/Hr)
Slope of intensity duration curve = 0.5300
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 101.000 to Point/Station 102.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 800.000(Ft.)
Top (of initial area) elevation = 1758.000(Ft.)
Bottom (of initial area) elevation = 1590.000(Ft.)
Difference in elevation = 168.000(Ft.)
Slope = 0.21000 s(percent)= 21.00
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 10.497 min.
Rainfall intensity = 1.386(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.554
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 6.021(CFS)
Total initial stream area = 7.850(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.000 to Point/Station 103.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1590.000(Ft.)
End of natural channel elevation = 1533.000(Ft.)
Length of natural channel = 1213.000(Ft.)
Estimated mean flow rate at midpoint of channel = 22.164(CFS) Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 6.68(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0470
Corrected/adjusted channel slope = 0.0470
Travel time = 3.03 min. TC = 13.52 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.554
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.750
Decimal fraction soil group C = 0.050
Decimal fraction soil group D = 0.200
RI index for soil(AMC 1) = 63.84
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.211(In/Hr) for a 2.0 year storm Subarea runoff = 28.268(CFS) for 42.090(Ac.)
Total runoff = 34.289(CFS) Total area = 49.940(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1533.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 1843.000(Ft.)
Estimated mean flow rate at midpoint of channel = 60.239(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 4.15(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0103
Corrected/adjusted channel slope = 0.0103
Travel time = 7.41 min. TC = 20.93 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.580
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.100
Decimal fraction soil group D = 0.650
RI index for soil(AMC 1) = 71.52
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 0.961(In/Hr) for a 2.0 year storm Subarea runoff = 42.120(CFS) for 75.590(Ac.)
Total runoff = 76.408(CFS) Total area = 125.530(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 125.530(Ac.)
Runoff from this stream = 76.408(CFS)
Time of concentration = 20.93 min.
Rainfall intensity = 0.961(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Process from Point/Station 105.000 to Point/Station 106.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 500.000(Ft.)
Top (of initial area) elevation = 1525.000(Ft.)
Bottom (of initial area) elevation = 1519.000(Ft.)
Difference in elevation = 6.000(Ft.)
Slope = 0.01200 s(percent)= 1.20
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 15.418 min.
Rainfall intensity = 1.130(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.617
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.750
RI index for soil(AMC 1) = 72.00
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 6.749(CFS)
Total initial stream area = 9.680(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1519.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 634.000(Ft.)
Estimated mean flow rate at midpoint of channel = 11.909(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 2.32(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0079
Corrected/adjusted channel slope = 0.0079
Travel time = 4.55 min. TC = 19.97 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.549
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 1) = 67.90
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 0.985(In/Hr) for a 2.0 year storm Subarea runoff = 8.004(CFS) for 14.800(Ac.)
Total runoff = 14.753(CFS) Total area = 24.480(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 24.480(Ac.)
Runoff from this stream = 14.753(CFS)
Time of concentration = 19.97 min.
Rainfall intensity = 0.985(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
1 76.408 20.93 0.961
2 14.753 19.97 0.985
Largest stream flow has longer time of concentration
Qp = 76.408 + sum of
Qb Ia/Ib
14.753 * 0.975 = 14.391
Qp = 90.800
Total of 2 streams to confluence:
Flow rates before confluence point:
76.408 14.753
Area of streams before confluence:
125.530 24.480
Results of confluence:
Total flow rate = 90.800(CFS)
Time of concentration = 20.929 min.
Effective stream area after confluence = 150.010(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 107.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1514.000(Ft.)
End of natural channel elevation = 1504.000(Ft.)
Length of natural channel = 897.000(Ft.)
Estimated mean flow rate at midpoint of channel = 98.326(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 4.99(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0111
Corrected/adjusted channel slope = 0.0111
Travel time = 3.00 min. TC = 23.93 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.531
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.400
Decimal fraction soil group C = 0.300
Decimal fraction soil group D = 0.300
RI index for soil(AMC 1) = 68.18
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 0.895(In/Hr) for a 2.0 year storm Subarea runoff = 11.822(CFS) for 24.870(Ac.)
Total runoff = 102.622(CFS) Total area = 174.880(Ac.) End of computations, total study area = 174.88 (Ac.) The following figures may
be used for a unit hydrograph study of the same area.
Area averaged pervious area fraction(Ap) = 1.000
Area averaged RI index number = 83.8
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
R
· Area ‘A’ – 10 Year Pre-Development Condition – Rational Method Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Riverside County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 04/30/21 File:EXA010.out ------------------------------------------------------------------------ TRACT 31194 - 'GOLDEN MEADOWS' HYDROLOGY STUDY – AREA ‘A’ EXISTING CONDITION RATIONAL METHOD - 100 YEAR STORM
HUNSAKER & ASSOCIATES,
BY: BRIAN LOWELL, PE
------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file
------------------------------------------------------------------------ Program License Serial Number 6406
------------------------------------------------------------------------ Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District 1978 hydrology manual
Storm event (year) = 10.00 Antecedent Moisture Condition = 2 2 year, 1 hour precipitation = 0.550(In.)
100 year, 1 hour precipitation = 1.300(In.)
Storm event year = 10.0
Calculated rainfall intensity data:
1 hour intensity = 0.859(In/Hr)
Slope of intensity duration curve = 0.5300
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 101.000 to Point/Station 102.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 800.000(Ft.)
Top (of initial area) elevation = 1758.000(Ft.)
Bottom (of initial area) elevation = 1590.000(Ft.)
Difference in elevation = 168.000(Ft.)
Slope = 0.21000 s(percent)= 21.00
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 10.497 min.
Rainfall intensity = 2.163(In/Hr) for a 10.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.767
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 2) = 78.00
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 13.017(CFS)
Total initial stream area = 7.850(Ac.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.000 to Point/Station 103.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1590.000(Ft.)
End of natural channel elevation = 1533.000(Ft.)
Length of natural channel = 1213.000(Ft.)
Estimated mean flow rate at midpoint of channel = 47.773(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 8.28(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0470
Corrected/adjusted channel slope = 0.0470
Travel time = 2.44 min. TC = 12.94 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.772
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.750
Decimal fraction soil group C = 0.050
Decimal fraction soil group D = 0.200
RI index for soil(AMC 2) = 80.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.936(In/Hr) for a 10.0 year storm Subarea runoff = 62.653(CFS) for 41.920(Ac.)
Total runoff = 75.670(CFS) Total area = 49.770(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1533.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 1843.000(Ft.)
Estimated mean flow rate at midpoint of channel = 131.620(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 5.24(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0103
Corrected/adjusted channel slope = 0.0103
Travel time = 5.87 min. TC = 18.80 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Runoff Coefficient = 0.791
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.100
Decimal fraction soil group D = 0.650
RI index for soil(AMC 2) = 85.95
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.588(In/Hr) for a 10.0 year storm Subarea runoff = 92.490(CFS) for 73.600(Ac.)
Total runoff = 168.160(CFS) Total area = 123.370(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 123.370(Ac.)
Runoff from this stream = 168.160(CFS)
Time of concentration = 18.80 min.
Rainfall intensity = 1.588(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 106.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 790.000(Ft.)
Top (of initial area) elevation = 1543.000(Ft.)
Bottom (of initial area) elevation = 1522.000(Ft.)
Difference in elevation = 21.000(Ft.)
Slope = 0.02658 s(percent)= 2.66
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 15.791 min.
Rainfall intensity = 1.742(In/Hr) for a 10.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.802
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.750
RI index for soil(AMC 2) = 86.25
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 9.082(CFS)
Total initial stream area = 6.500(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1519.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 634.000(Ft.)
Estimated mean flow rate at midpoint of channel = 21.881(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 2.73(Ft/s)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0079
Corrected/adjusted channel slope = 0.0079
Travel time = 3.88 min. TC = 19.67 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.769
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 2) = 83.50
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.551(In/Hr) for a 10.0 year storm Subarea runoff = 21.854(CFS) for 18.320(Ac.)
Total runoff = 30.936(CFS) Total area = 24.820(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 24.820(Ac.)
Runoff from this stream = 30.936(CFS)
Time of concentration = 19.67 min.
Rainfall intensity = 1.551(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 168.160 18.80 1.588
2 30.936 19.67 1.551
Largest stream flow has longer or shorter time of concentration Qp = 168.160 + sum of
Qa Tb/Ta
30.936 * 0.956 = 29.580
Qp = 197.740
Total of 2 streams to confluence:
Flow rates before confluence point:
168.160 30.936
Area of streams before confluence:
123.370 24.820
Results of confluence:
Total flow rate = 197.740(CFS)
Time of concentration = 18.804 min.
Effective stream area after confluence = 148.190(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 107.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1514.000(Ft.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
End of natural channel elevation = 1504.000(Ft.)
Length of natural channel = 897.000(Ft.)
Estimated mean flow rate at midpoint of channel = 214.446(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 6.33(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0111
Corrected/adjusted channel slope = 0.0111
Travel time = 2.36 min. TC = 21.17 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.767
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.400
Decimal fraction soil group C = 0.300
Decimal fraction soil group D = 0.300
RI index for soil(AMC 2) = 83.70
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.491(In/Hr) for a 10.0 year storm Subarea runoff = 28.626(CFS) for 25.040(Ac.)
Total runoff = 226.366(CFS) Total area = 173.230(Ac.) End of computations, total study area = 173.23 (Ac.) The following figures may
be used for a unit hydrograph study of the same area.
Area averaged pervious area fraction(Ap) = 1.000
Area averaged RI index number = 83.7
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
· Area ‘A’ – 100 Year Pre-Development Condition – Rational Method Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Riverside County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 04/30/21 File:EXA100.out ------------------------------------------------------------------------ TRACT 31194 - 'GOLDEN MEADOWS' HYDROLOGY STUDY – AREA ‘A’ EXISTING CONDITION RATIONAL METHOD - 100 YEAR STORM
HUNSAKER & ASSOCIATES,
BY: BRIAN LOWELL, PE
------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file
------------------------------------------------------------------------ Program License Serial Number 6406
------------------------------------------------------------------------ Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District 1978 hydrology manual
Storm event (year) = 100.00 Antecedent Moisture Condition = 3 2 year, 1 hour precipitation = 0.550(In.)
100 year, 1 hour precipitation = 1.300(In.)
Storm event year = 100.0
Calculated rainfall intensity data:
1 hour intensity = 1.300(In/Hr)
Slope of intensity duration curve = 0.5300
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 101.000 to Point/Station 102.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 800.000(Ft.)
Top (of initial area) elevation = 1758.000(Ft.)
Bottom (of initial area) elevation = 1590.000(Ft.)
Difference in elevation = 168.000(Ft.)
Slope = 0.21000 s(percent)= 21.00
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 10.497 min.
Rainfall intensity = 3.275(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.860
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 3) = 89.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 22.114(CFS)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Total initial stream area = 7.850(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.000 to Point/Station 103.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1590.000(Ft.)
End of natural channel elevation = 1533.000(Ft.)
Length of natural channel = 1213.000(Ft.)
Estimated mean flow rate at midpoint of channel = 81.161(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 9.67(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0470
Corrected/adjusted channel slope = 0.0470
Travel time = 2.09 min. TC = 12.59 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.863
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.750
Decimal fraction soil group C = 0.050
Decimal fraction soil group D = 0.200
RI index for soil(AMC 3) = 91.36
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 2.974(In/Hr) for a 100.0 year storm Subarea runoff = 107.650(CFS) for 41.920(Ac.)
Total runoff = 129.765(CFS) Total area = 49.770(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1533.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 1843.000(Ft.)
Estimated mean flow rate at midpoint of channel = 225.713(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 6.18(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0103
Corrected/adjusted channel slope = 0.0103
Travel time = 4.97 min. TC = 17.56 min.
Adding area flow to channel
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.872
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.100
Decimal fraction soil group D = 0.650
RI index for soil(AMC 3) = 94.38
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 2.494(In/Hr) for a 100.0 year storm Subarea runoff = 160.075(CFS) for 73.600(Ac.)
Total runoff = 289.840(CFS) Total area = 123.370(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 123.370(Ac.)
Runoff from this stream = 289.840(CFS)
Time of concentration = 17.56 min.
Rainfall intensity = 2.494(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 106.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 790.000(Ft.)
Top (of initial area) elevation = 1543.000(Ft.)
Bottom (of initial area) elevation = 1522.000(Ft.)
Difference in elevation = 21.000(Ft.)
Slope = 0.02658 s(percent)= 2.66
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 15.791 min.
Rainfall intensity = 2.638(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.874
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.250
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.750
RI index for soil(AMC 3) = 94.50
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 14.989(CFS)
Total initial stream area = 6.500(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1519.000(Ft.)
End of natural channel elevation = 1514.000(Ft.)
Length of natural channel = 634.000(Ft.)
Estimated mean flow rate at midpoint of channel = 36.112(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Velocity using mean channel flow = 3.13(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0079
Corrected/adjusted channel slope = 0.0079
Travel time = 3.37 min. TC = 19.16 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.864
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 3) = 93.10
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 2.380(In/Hr) for a 100.0 year storm Subarea runoff = 37.683(CFS) for 18.320(Ac.)
Total runoff = 52.672(CFS) Total area = 24.820(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 104.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 24.820(Ac.)
Runoff from this stream = 52.672(CFS)
Time of concentration = 19.16 min.
Rainfall intensity = 2.380(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 289.840 17.56 2.494
2 52.672 19.16 2.380
Largest stream flow has longer or shorter time of concentration Qp = 289.840 + sum of
Qa Tb/Ta
52.672 * 0.916 = 48.252
Qp = 338.092
Total of 2 streams to confluence:
Flow rates before confluence point:
289.840 52.672
Area of streams before confluence:
123.370 24.820
Results of confluence:
Total flow rate = 338.092(CFS)
Time of concentration = 17.556 min.
Effective stream area after confluence = 148.190(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 107.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Top of natural channel elevation = 1514.000(Ft.)
End of natural channel elevation = 1504.000(Ft.)
Length of natural channel = 897.000(Ft.)
Estimated mean flow rate at midpoint of channel = 366.656(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 7.49(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.0111
Corrected/adjusted channel slope = 0.0111
Travel time = 2.00 min. TC = 19.55 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.864
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.400
Decimal fraction soil group C = 0.300
Decimal fraction soil group D = 0.300
RI index for soil(AMC 3) = 93.22
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 2.355(In/Hr) for a 100.0 year storm Subarea runoff = 50.978(CFS) for 25.040(Ac.)
Total runoff = 389.070(CFS) Total area = 173.230(Ac.) End of computations, total study area = 173.23 (Ac.) The following figures may
be used for a unit hydrograph study of the same area.
Area averaged pervious area fraction(Ap) = 1.000
Area averaged RI index number = 83.7
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
· Area ‘A’ – 2 Year Post-Development Condition – Rational Method Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Riverside County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 11/08/21 File:PR002.out ------------------------------------------------------------------------ TRACT 31194 - 'GOLDEN MEADOWS' MAJOR MODIFICATION
PRELIMINARY HYDROLOGY STUDY – AREA ‘A’
DEVELOPED CONDITION RATIONAL METHOD - 2 YEAR STORM
HUNSAKER & ASSOCIATES, MAY 2021, BRIAN LOWELL, PE
------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file
------------------------------------------------------------------------ Program License Serial Number 6406
------------------------------------------------------------------------ Rational Method Hydrology Program based on
Riverside County Flood Control & Water Conservation District 1978 hydrology manual
Storm event (year) = 2.00 Antecedent Moisture Condition = 1 2 year, 1 hour precipitation = 0.550(In.)
100 year, 1 hour precipitation = 1.300(In.)
Storm event year = 2.0
Calculated rainfall intensity data:
1 hour intensity = 0.550(In/Hr)
Slope of intensity duration curve = 0.5300
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 100.000 to Point/Station 101.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 448.000(Ft.)
Top (of initial area) elevation = 1800.000(Ft.)
Bottom (of initial area) elevation = 1660.000(Ft.)
Difference in elevation = 140.000(Ft.)
Slope = 0.31250 s(percent)= 31.25
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 7.688 min.
Rainfall intensity = 1.634(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.588
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 3.152(CFS)
Total initial stream area = 3.280(Ac.)
Pervious area fraction = 1.000
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 101.000 to Point/Station 102.000 **** NATURAL CHANNEL TIME + SUBAREA FLOW ADDITION ****
______________________________________________________________________ Top of natural channel elevation = 1660.000(Ft.)
End of natural channel elevation = 1565.300(Ft.)
Length of natural channel = 618.000(Ft.)
Estimated mean flow rate at midpoint of channel = 7.534(CFS) Natural valley channel type used
L.A. County flood control district formula for channel velocity:
Velocity(ft/s) = (7 + 8(q(English Units)^.352)(slope^0.5) Velocity using mean channel flow = 8.61(Ft/s)
Correction to map slope used on extremely rugged channels with drops and waterfalls (Plate D-6.2)
Normal channel slope = 0.1532
Corrected/adjusted channel slope = 0.1366
Travel time = 1.20 min. TC = 8.88 min.
Adding area flow to channel
UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.572
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.514(In/Hr) for a 2.0 year storm Subarea runoff = 7.899(CFS) for 9.120(Ac.)
Total runoff = 11.051(CFS) Total area = 12.400(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.000 to Point/Station 102.100 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1565.300(Ft.)
Downstream point/station elevation = 1563.000(Ft.)
Pipe length = 123.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 11.051(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 11.051(CFS)
Normal flow depth in pipe = 11.84(In.)
Flow top width inside pipe = 17.08(In.)
Critical Depth = 15.27(In.)
Pipe flow velocity = 8.96(Ft/s)
Travel time through pipe = 0.23 min.
Time of concentration (TC) = 9.11 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.100 to Point/Station 102.100 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.624
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Pervious area fraction = 0.500; Impervious fraction = 0.500 Time of concentration = 9.11 min.
Rainfall intensity = 1.493(In/Hr) for a 2.0 year storm Subarea runoff = 0.960(CFS) for 1.030(Ac.)
Total runoff = 12.011(CFS) Total area = 13.430(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.100 to Point/Station 103.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1563.000(Ft.)
Downstream point/station elevation = 1549.000(Ft.)
Pipe length = 671.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 12.011(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 12.011(CFS)
Normal flow depth in pipe = 12.09(In.)
Flow top width inside pipe = 16.90(In.)
Critical Depth = 15.76(In.)
Pipe flow velocity = 9.52(Ft/s)
Travel time through pipe = 1.17 min.
Time of concentration (TC) = 10.29 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 102.100 to Point/Station 103.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 13.430(Ac.)
Runoff from this stream = 12.011(CFS)
Time of concentration = 10.29 min.
Rainfall intensity = 1.400(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 12.011 10.29 1.400
Largest stream flow has longer time of concentration
Qp = 12.011 + sum of
Qp = 12.011
Total of 1 streams to confluence:
Flow rates before confluence point:
12.011
Area of streams before confluence:
13.430
Results of confluence:
Total flow rate = 12.011(CFS)
Time of concentration = 10.288 min.
Effective stream area after confluence = 13.430(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 105.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 425.000(Ft.)
Top (of initial area) elevation = 1572.000(Ft.)
Bottom (of initial area) elevation = 1556.200(Ft.)
Difference in elevation = 15.800(Ft.)
Slope = 0.03718 s(percent)= 3.72
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 8.479 min.
Rainfall intensity = 1.551(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.628
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 0.926(CFS)
Total initial stream area = 0.950(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 103.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1549.200(Ft.)
Downstream point/station elevation = 1549.000(Ft.)
Pipe length = 15.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 0.926(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 0.926(CFS)
Normal flow depth in pipe = 4.42(In.)
Flow top width inside pipe = 9.00(In.)
Critical Depth = 5.29(In.)
Pipe flow velocity = 4.29(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 8.54 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 103.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 0.950(Ac.)
Runoff from this stream = 0.926(CFS)
Time of concentration = 8.54 min.
Rainfall intensity = 1.546(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 12.011 10.29 1.400
2 0.926 8.54 1.546
Largest stream flow has longer time of concentration
Qp = 12.011 + sum of
Qb Ia/Ib
0.926 * 0.906 = 0.839
Qp = 12.849
Total of 2 streams to confluence:
Flow rates before confluence point:
12.011 0.926
Area of streams before confluence:
13.430 0.950
Results of confluence:
Total flow rate = 12.849(CFS)
Time of concentration = 10.288 min.
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Effective stream area after confluence = 14.380(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 106.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1549.000(Ft.)
Downstream point/station elevation = 1548.700(Ft.)
Pipe length = 29.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 12.849(CFS)
Nearest computed pipe diameter = 21.00(In.)
Calculated individual pipe flow = 12.849(CFS)
Normal flow depth in pipe = 14.18(In.)
Flow top width inside pipe = 19.67(In.)
Critical Depth = 16.03(In.)
Pipe flow velocity = 7.44(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 10.35 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 106.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 14.380(Ac.)
Runoff from this stream = 12.849(CFS)
Time of concentration = 10.35 min.
Rainfall intensity = 1.396(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 107.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 553.000(Ft.)
Top (of initial area) elevation = 1572.000(Ft.)
Bottom (of initial area) elevation = 1564.600(Ft.)
Difference in elevation = 7.400(Ft.)
Slope = 0.01338 s(percent)= 1.34
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 11.557 min.
Rainfall intensity = 1.317(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.611
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 0.949(CFS)
Total initial stream area = 1.180(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 107.000 to Point/Station 108.000 **** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION **** ______________________________________________________________________ Top of street segment elevation = 1564.600(Ft.)
End of street segment elevation = 1556.200(Ft.)
Length of street segment = 684.000(Ft.)
Height of curb above gutter flowline = 6.0(In.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Width of half street (curb to crown) = 18.000(Ft.)
Distance from crown to crossfall grade break = 16.000(Ft.) Slope from gutter to grade break (v/hz) = 0.020
Slope from grade break to crown (v/hz) = 0.020
Street flow is on [1] side(s) of the street
Distance from curb to property line = 10.000(Ft.)
Slope from curb to property line (v/hz) = 0.020
Gutter width = 2.000(Ft.)
Gutter hike from flowline = 2.000(In.)
Manning's N in gutter = 0.0130
Manning's N from gutter to grade break = 0.0130
Manning's N from grade break to crown = 0.0130
Estimated mean flow rate at midpoint of street = 1.553(CFS) Depth of flow = 0.269(Ft.), Average velocity = 2.459(Ft/s) Streetflow hydraulics at midpoint of street travel:
Halfstreet flow width = 7.105(Ft.)
Flow velocity = 2.46(Ft/s)
Travel time = 4.64 min. TC = 16.19 min.
Adding area flow to street
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.612
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.750
Decimal fraction soil group C = 0.050
Decimal fraction soil group D = 0.200
RI index for soil(AMC 1) = 40.45
Pervious area fraction = 0.500; Impervious fraction = 0.500 Rainfall intensity = 1.101(In/Hr) for a 2.0 year storm Subarea runoff = 1.152(CFS) for 1.710(Ac.)
Total runoff = 2.101(CFS) Total area = 2.890(Ac.) Street flow at end of street = 2.101(CFS)
Half street flow at end of street = 2.101(CFS)
Depth of flow = 0.291(Ft.), Average velocity = 2.621(Ft/s) Flow width (from curb towards crown)= 8.214(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 108.000 to Point/Station 106.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1549.200(Ft.)
Downstream point/station elevation = 1548.700(Ft.)
Pipe length = 42.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 2.101(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 2.101(CFS)
Normal flow depth in pipe = 6.28(In.)
Flow top width inside pipe = 11.99(In.)
Critical Depth = 7.43(In.)
Pipe flow velocity = 5.04(Ft/s)
Travel time through pipe = 0.14 min.
Time of concentration (TC) = 16.33 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 108.000 to Point/Station 106.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 2.890(Ac.)
Runoff from this stream = 2.101(CFS)
Time of concentration = 16.33 min.
Rainfall intensity = 1.096(In/Hr)
Summary of stream data:
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 12.849 10.35 1.396
2 2.101 16.33 1.096
Largest stream flow has longer or shorter time of concentration Qp = 12.849 + sum of
Qa Tb/Ta
2.101 * 0.634 = 1.332
Qp = 14.181
Total of 2 streams to confluence:
Flow rates before confluence point:
12.849 2.101
Area of streams before confluence:
14.380 2.890
Results of confluence:
Total flow rate = 14.181(CFS)
Time of concentration = 10.353 min.
Effective stream area after confluence = 17.270(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 109.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1548.700(Ft.)
Downstream point/station elevation = 1523.000(Ft.)
Pipe length = 620.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 14.181(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 14.181(CFS)
Normal flow depth in pipe = 10.71(In.)
Flow top width inside pipe = 17.67(In.)
Critical Depth = 16.64(In.)
Pipe flow velocity = 12.94(Ft/s)
Travel time through pipe = 0.80 min.
Time of concentration (TC) = 11.15 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 106.000 to Point/Station 109.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 17.270(Ac.)
Runoff from this stream = 14.181(CFS)
Time of concentration = 11.15 min.
Rainfall intensity = 1.342(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 110.000 to Point/Station 111.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 530.000(Ft.)
Top (of initial area) elevation = 1540.000(Ft.)
Bottom (of initial area) elevation = 1530.000(Ft.)
Difference in elevation = 10.000(Ft.)
Slope = 0.01887 s(percent)= 1.89
TC = k(0.710)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 19.312 min.
Rainfall intensity = 1.003(In/Hr) for a 2.0 year storm UNDEVELOPED (fair cover) subarea
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Runoff Coefficient = 0.529
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.150
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.850
RI index for soil(AMC 1) = 65.45
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 1.560(CFS)
Total initial stream area = 2.940(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 111.000 to Point/Station 109.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1523.400(Ft.)
Downstream point/station elevation = 1523.000(Ft.)
Pipe length = 40.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.560(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.560(CFS)
Normal flow depth in pipe = 6.95(In.)
Flow top width inside pipe = 7.55(In.)
Critical Depth = 6.90(In.)
Pipe flow velocity = 4.26(Ft/s)
Travel time through pipe = 0.16 min.
Time of concentration (TC) = 19.47 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 111.000 to Point/Station 109.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 2.940(Ac.)
Runoff from this stream = 1.560(CFS)
Time of concentration = 19.47 min.
Rainfall intensity = 0.999(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 14.181 11.15 1.342
2 1.560 19.47 0.999
Largest stream flow has longer or shorter time of concentration Qp = 14.181 + sum of
Qa Tb/Ta
1.560 * 0.573 = 0.893
Qp = 15.074
Total of 2 streams to confluence:
Flow rates before confluence point:
14.181 1.560
Area of streams before confluence:
17.270 2.940
Results of confluence:
Total flow rate = 15.074(CFS)
Time of concentration = 11.151 min.
Effective stream area after confluence = 20.210(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Process from Point/Station 109.000 to Point/Station 112.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1523.000(Ft.)
Downstream point/station elevation = 1520.800(Ft.)
Pipe length = 38.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 15.074(CFS)
Nearest computed pipe diameter = 15.00(In.)
Calculated individual pipe flow = 15.074(CFS)
Normal flow depth in pipe = 11.91(In.)
Flow top width inside pipe = 12.14(In.)
Critical depth could not be calculated.
Pipe flow velocity = 14.43(Ft/s)
Travel time through pipe = 0.04 min.
Time of concentration (TC) = 11.20 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 109.000 to Point/Station 112.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 20.210(Ac.)
Runoff from this stream = 15.074(CFS)
Time of concentration = 11.20 min.
Rainfall intensity = 1.339(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 113.000 to Point/Station 114.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 965.000(Ft.)
Top (of initial area) elevation = 1567.900(Ft.)
Bottom (of initial area) elevation = 1556.000(Ft.)
Difference in elevation = 11.900(Ft.)
Slope = 0.01233 s(percent)= 1.23
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 14.678 min.
Rainfall intensity = 1.160(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.650
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.300
Decimal fraction soil group C = 0.300
Decimal fraction soil group D = 0.400
RI index for soil(AMC 1) = 48.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 2.135(CFS)
Total initial stream area = 2.830(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 114.000 to Point/Station 115.000 **** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION **** ______________________________________________________________________ Top of street segment elevation = 1556.000(Ft.)
End of street segment elevation = 1529.800(Ft.)
Length of street segment = 610.000(Ft.)
Height of curb above gutter flowline = 6.0(In.)
Width of half street (curb to crown) = 18.000(Ft.)
Distance from crown to crossfall grade break = 16.000(Ft.) Slope from gutter to grade break (v/hz) = 0.020
Slope from grade break to crown (v/hz) = 0.020
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Street flow is on [1] side(s) of the street
Distance from curb to property line = 10.000(Ft.)
Slope from curb to property line (v/hz) = 0.020
Gutter width = 2.000(Ft.)
Gutter hike from flowline = 2.000(In.)
Manning's N in gutter = 0.0130
Manning's N from gutter to grade break = 0.0130
Manning's N from grade break to crown = 0.0130
Estimated mean flow rate at midpoint of street = 2.847(CFS) Depth of flow = 0.267(Ft.), Average velocity = 4.581(Ft/s) Streetflow hydraulics at midpoint of street travel:
Halfstreet flow width = 7.035(Ft.)
Flow velocity = 4.58(Ft/s)
Travel time = 2.22 min. TC = 16.90 min.
Adding area flow to street
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.615
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.700
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.300
RI index for soil(AMC 1) = 41.70
Pervious area fraction = 0.500; Impervious fraction = 0.500 Rainfall intensity = 1.077(In/Hr) for a 2.0 year storm Subarea runoff = 1.330(CFS) for 2.010(Ac.)
Total runoff = 3.465(CFS) Total area = 4.840(Ac.) Street flow at end of street = 3.465(CFS)
Half street flow at end of street = 3.465(CFS)
Depth of flow = 0.282(Ft.), Average velocity = 4.772(Ft/s) Flow width (from curb towards crown)= 7.743(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 115.000 to Point/Station 112.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1521.200(Ft.)
Downstream point/station elevation = 1520.800(Ft.)
Pipe length = 30.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 3.465(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 3.465(CFS)
Normal flow depth in pipe = 8.44(In.)
Flow top width inside pipe = 10.97(In.)
Critical Depth = 9.55(In.)
Pipe flow velocity = 5.87(Ft/s)
Travel time through pipe = 0.09 min.
Time of concentration (TC) = 16.98 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 115.000 to Point/Station 112.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 4.840(Ac.)
Runoff from this stream = 3.465(CFS)
Time of concentration = 16.98 min.
Rainfall intensity = 1.074(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 127.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Initial area flow distance = 623.000(Ft.)
Top (of initial area) elevation = 1572.000(Ft.)
Bottom (of initial area) elevation = 1552.000(Ft.)
Difference in elevation = 20.000(Ft.)
Slope = 0.03210 s(percent)= 3.21
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 10.175 min.
Rainfall intensity = 1.409(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.618
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.549(CFS)
Total initial stream area = 1.780(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 127.000 to Point/Station 128.000 **** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION **** ______________________________________________________________________ Top of street segment elevation = 1552.000(Ft.)
End of street segment elevation = 1529.800(Ft.)
Length of street segment = 518.000(Ft.)
Height of curb above gutter flowline = 6.0(In.)
Width of half street (curb to crown) = 18.000(Ft.)
Distance from crown to crossfall grade break = 16.000(Ft.) Slope from gutter to grade break (v/hz) = 0.020
Slope from grade break to crown (v/hz) = 0.020
Street flow is on [1] side(s) of the street
Distance from curb to property line = 10.000(Ft.)
Slope from curb to property line (v/hz) = 0.020
Gutter width = 2.000(Ft.)
Gutter hike from flowline = 2.000(In.)
Manning's N in gutter = 0.0130
Manning's N from gutter to grade break = 0.0130
Manning's N from grade break to crown = 0.0130
Estimated mean flow rate at midpoint of street = 2.352(CFS) Depth of flow = 0.254(Ft.), Average velocity = 4.407(Ft/s) Streetflow hydraulics at midpoint of street travel:
Halfstreet flow width = 6.381(Ft.)
Flow velocity = 4.41(Ft/s)
Travel time = 1.96 min. TC = 12.13 min.
Adding area flow to street
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.633
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.700
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.300
RI index for soil(AMC 1) = 41.70
Pervious area fraction = 0.500; Impervious fraction = 0.500 Rainfall intensity = 1.283(In/Hr) for a 2.0 year storm Subarea runoff = 1.552(CFS) for 1.910(Ac.)
Total runoff = 3.101(CFS) Total area = 3.690(Ac.) Street flow at end of street = 3.101(CFS)
Half street flow at end of street = 3.101(CFS)
Depth of flow = 0.274(Ft.), Average velocity = 4.658(Ft/s) Flow width (from curb towards crown)= 7.343(Ft.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 128.000 to Point/Station 112.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1521.200(Ft.)
Downstream point/station elevation = 1520.800(Ft.)
Pipe length = 45.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 3.101(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 3.101(CFS)
Normal flow depth in pipe = 9.09(In.)
Flow top width inside pipe = 10.28(In.)
Critical Depth = 9.06(In.)
Pipe flow velocity = 4.85(Ft/s)
Travel time through pipe = 0.15 min.
Time of concentration (TC) = 12.29 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 128.000 to Point/Station 112.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 3
Stream flow area = 3.690(Ac.)
Runoff from this stream = 3.101(CFS)
Time of concentration = 12.29 min.
Rainfall intensity = 1.274(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 15.074 11.20 1.339
2 3.465 16.98 1.074
3 3.101 12.29 1.274
Largest stream flow has longer or shorter time of concentration Qp = 15.074 + sum of
Qa Tb/Ta
3.465 * 0.659 = 2.284
Qa Tb/Ta
3.101 * 0.911 = 2.825
Qp = 20.184
Total of 3 streams to confluence:
Flow rates before confluence point:
15.074 3.465 3.101
Area of streams before confluence:
20.210 4.840 3.690
Results of confluence:
Total flow rate = 20.184(CFS)
Time of concentration = 11.195 min.
Effective stream area after confluence = 28.740(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 112.000 to Point/Station 116.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1520.800(Ft.)
Downstream point/station elevation = 1520.000(Ft.)
Pipe length = 32.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 20.184(CFS)
Nearest computed pipe diameter = 21.00(In.)
Calculated individual pipe flow = 20.184(CFS)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Normal flow depth in pipe = 14.27(In.)
Flow top width inside pipe = 19.60(In.)
Critical Depth = 19.24(In.)
Pipe flow velocity = 11.59(Ft/s)
Travel time through pipe = 0.05 min.
Time of concentration (TC) = 11.24 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 112.000 to Point/Station 116.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 28.740(Ac.)
Runoff from this stream = 20.184(CFS)
Time of concentration = 11.24 min.
Rainfall intensity = 1.336(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 117.000 to Point/Station 118.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 500.000(Ft.)
Top (of initial area) elevation = 1543.800(Ft.)
Bottom (of initial area) elevation = 1539.300(Ft.)
Difference in elevation = 4.500(Ft.)
Slope = 0.00900 s(percent)= 0.90
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 12.017 min.
Rainfall intensity = 1.290(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.651
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 1) = 45.60
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 0.748(CFS)
Total initial stream area = 0.890(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 118.000 to Point/Station 119.000 **** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION **** ______________________________________________________________________ Top of street segment elevation = 1539.300(Ft.)
End of street segment elevation = 1529.800(Ft.)
Length of street segment = 933.000(Ft.)
Height of curb above gutter flowline = 8.0(In.)
Width of half street (curb to crown) = 38.000(Ft.)
Distance from crown to crossfall grade break = 20.000(Ft.) Slope from gutter to grade break (v/hz) = 0.020
Slope from grade break to crown (v/hz) = 0.020
Street flow is on [1] side(s) of the street
Distance from curb to property line = 40.000(Ft.)
Slope from curb to property line (v/hz) = 0.020
Gutter width = 2.000(Ft.)
Gutter hike from flowline = 2.000(In.)
Manning's N in gutter = 0.0130
Manning's N from gutter to grade break = 0.0130
Manning's N from grade break to crown = 0.0130
Estimated mean flow rate at midpoint of street = 1.339(CFS) Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Depth of flow = 0.265(Ft.), Average velocity = 2.215(Ft/s) Streetflow hydraulics at midpoint of street travel:
Halfstreet flow width = 6.914(Ft.)
Flow velocity = 2.21(Ft/s)
Travel time = 7.02 min. TC = 19.04 min.
Adding area flow to street
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.645
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.300
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.700
RI index for soil(AMC 1) = 50.16
Pervious area fraction = 0.500; Impervious fraction = 0.500 Rainfall intensity = 1.011(In/Hr) for a 2.0 year storm Subarea runoff = 1.101(CFS) for 1.690(Ac.)
Total runoff = 1.849(CFS) Total area = 2.580(Ac.) Street flow at end of street = 1.849(CFS)
Half street flow at end of street = 1.849(CFS)
Depth of flow = 0.288(Ft.), Average velocity = 2.369(Ft/s) Flow width (from curb towards crown)= 8.085(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 119.000 to Point/Station 116.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1521.400(Ft.)
Downstream point/station elevation = 1520.000(Ft.)
Pipe length = 57.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.849(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.849(CFS)
Normal flow depth in pipe = 5.62(In.)
Flow top width inside pipe = 8.72(In.)
Critical Depth = 7.46(In.)
Pipe flow velocity = 6.38(Ft/s)
Travel time through pipe = 0.15 min.
Time of concentration (TC) = 19.19 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 119.000 to Point/Station 116.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 2.580(Ac.)
Runoff from this stream = 1.849(CFS)
Time of concentration = 19.19 min.
Rainfall intensity = 1.006(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 20.184 11.24 1.336
2 1.849 19.19 1.006
Largest stream flow has longer or shorter time of concentration Qp = 20.184 + sum of
Qa Tb/Ta
1.849 * 0.586 = 1.083
Qp = 21.267
Total of 2 streams to confluence:
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Flow rates before confluence point:
20.184 1.849
Area of streams before confluence:
28.740 2.580
Results of confluence:
Total flow rate = 21.267(CFS)
Time of concentration = 11.241 min.
Effective stream area after confluence = 31.320(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 116.000 to Point/Station 120.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1520.000(Ft.)
Downstream point/station elevation = 1519.500(Ft.)
Pipe length = 54.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 21.267(CFS)
Nearest computed pipe diameter = 24.00(In.)
Calculated individual pipe flow = 21.267(CFS)
Normal flow depth in pipe = 19.17(In.)
Flow top width inside pipe = 19.24(In.)
Critical Depth = 19.82(In.)
Pipe flow velocity = 7.90(Ft/s)
Travel time through pipe = 0.11 min.
Time of concentration (TC) = 11.36 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 116.000 to Point/Station 120.000 **** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 1
Stream flow area = 31.320(Ac.)
Runoff from this stream = 21.267(CFS)
Time of concentration = 11.36 min.
Rainfall intensity = 1.329(In/Hr)
Program is now starting with Main Stream No. 2
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 121.000 to Point/Station 122.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 193.000(Ft.)
Top (of initial area) elevation = 1546.000(Ft.)
Bottom (of initial area) elevation = 1544.700(Ft.)
Difference in elevation = 1.300(Ft.)
Slope = 0.00674 s(percent)= 0.67
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 8.702 min.
Rainfall intensity = 1.530(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.722
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 1.000
RI index for soil(AMC 1) = 57.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.071(CFS)
Total initial stream area = 0.970(Ac.)
Pervious area fraction = 0.500
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 122.000 to Point/Station 123.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1537.700(Ft.)
Downstream point/station elevation = 1531.700(Ft.)
Pipe length = 496.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.071(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.071(CFS)
Normal flow depth in pipe = 4.96(In.)
Flow top width inside pipe = 8.95(In.)
Critical Depth = 5.70(In.)
Pipe flow velocity = 4.28(Ft/s)
Travel time through pipe = 1.93 min.
Time of concentration (TC) = 10.63 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 122.000 to Point/Station 123.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 1
Stream flow area = 0.970(Ac.)
Runoff from this stream = 1.071(CFS)
Time of concentration = 10.63 min.
Rainfall intensity = 1.376(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 124.000 to Point/Station 125.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 960.000(Ft.)
Top (of initial area) elevation = 1549.500(Ft.)
Bottom (of initial area) elevation = 1539.000(Ft.)
Difference in elevation = 10.500(Ft.)
Slope = 0.01094 s(percent)= 1.09
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 15.003 min.
Rainfall intensity = 1.147(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.649
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.400
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.600
RI index for soil(AMC 1) = 47.88
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 3.413(CFS)
Total initial stream area = 4.590(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 125.000 to Point/Station 123.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1532.000(Ft.)
Downstream point/station elevation = 1531.700(Ft.)
Pipe length = 26.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 3.413(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 3.413(CFS)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Normal flow depth in pipe = 8.84(In.)
Flow top width inside pipe = 10.57(In.)
Critical Depth = 9.48(In.)
Pipe flow velocity = 5.51(Ft/s)
Travel time through pipe = 0.08 min.
Time of concentration (TC) = 15.08 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 125.000 to Point/Station 123.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 2
Stream flow area = 4.590(Ac.)
Runoff from this stream = 3.413(CFS)
Time of concentration = 15.08 min.
Rainfall intensity = 1.143(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 124.000 to Point/Station 126.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 1000.000(Ft.)
Top (of initial area) elevation = 1549.500(Ft.)
Bottom (of initial area) elevation = 1539.000(Ft.)
Difference in elevation = 10.500(Ft.)
Slope = 0.01050 s(percent)= 1.05
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 15.375 min.
Rainfall intensity = 1.132(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.657
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.300
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.700
RI index for soil(AMC 1) = 50.16
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 3.720(CFS)
Total initial stream area = 5.000(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 126.000 to Point/Station 123.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1532.000(Ft.)
Downstream point/station elevation = 1531.700(Ft.)
Pipe length = 20.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 3.720(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 3.720(CFS)
Normal flow depth in pipe = 8.52(In.)
Flow top width inside pipe = 10.89(In.)
Critical Depth = 9.85(In.)
Pipe flow velocity = 6.24(Ft/s)
Travel time through pipe = 0.05 min.
Time of concentration (TC) = 15.43 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 126.000 to Point/Station 123.000 **** CONFLUENCE OF MINOR STREAMS ****
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 3
Stream flow area = 5.000(Ac.)
Runoff from this stream = 3.720(CFS)
Time of concentration = 15.43 min.
Rainfall intensity = 1.130(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 1.071 10.63 1.376
2 3.413 15.08 1.143
3 3.720 15.43 1.130
Largest stream flow has longer time of concentration
Qp = 3.720 + sum of
Qb Ia/Ib
1.071 * 0.821 = 0.879
Qb Ia/Ib
3.413 * 0.988 = 3.373
Qp = 7.971
Total of 3 streams to confluence:
Flow rates before confluence point:
1.071 3.413 3.720
Area of streams before confluence:
0.970 4.590 5.000
Results of confluence:
Total flow rate = 7.971(CFS)
Time of concentration = 15.429 min.
Effective stream area after confluence = 10.560(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 123.000 to Point/Station 120.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1531.700(Ft.)
Downstream point/station elevation = 1519.500(Ft.)
Pipe length = 800.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 7.971(CFS)
Nearest computed pipe diameter = 15.00(In.)
Calculated individual pipe flow = 7.971(CFS)
Normal flow depth in pipe = 15.00(In.)
Flow top width inside pipe = 0.00(In.)
Critical Depth = 13.37(In.)
Pipe flow velocity = 6.50(Ft/s)
Travel time through pipe = 2.05 min.
Time of concentration (TC) = 17.48 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 123.000 to Point/Station 120.000 **** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 2
Stream flow area = 10.560(Ac.)
Runoff from this stream = 7.971(CFS)
Time of concentration = 17.48 min.
Rainfall intensity = 1.057(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
No. (CFS) (min) (In/Hr)
1 21.267 11.36 1.329
2 7.971 17.48 1.057
Largest stream flow has longer or shorter time of concentration Qp = 21.267 + sum of
Qa Tb/Ta
7.971 * 0.650 = 5.178
Qp = 26.445
Total of 2 main streams to confluence:
Flow rates before confluence point:
21.267 7.971
Area of streams before confluence:
31.320 10.560
Results of confluence:
Total flow rate = 26.445(CFS)
Time of concentration = 11.355 min.
Effective stream area after confluence = 41.880(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 120.000 to Point/Station 128.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1519.500(Ft.)
Downstream point/station elevation = 1509.000(Ft.)
Pipe length = 1360.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 26.445(CFS)
Nearest computed pipe diameter = 27.00(In.)
Calculated individual pipe flow = 26.445(CFS)
Normal flow depth in pipe = 21.47(In.)
Flow top width inside pipe = 21.79(In.)
Critical Depth = 21.54(In.)
Pipe flow velocity = 7.80(Ft/s)
Travel time through pipe = 2.91 min.
Time of concentration (TC) = 14.26 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 120.000 to Point/Station 128.000 **** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 1
Stream flow area = 41.880(Ac.)
Runoff from this stream = 26.445(CFS)
Time of concentration = 14.26 min.
Rainfall intensity = 1.178(In/Hr)
Program is now starting with Main Stream No. 2
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 158.000 to Point/Station 159.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 245.000(Ft.)
Top (of initial area) elevation = 1720.000(Ft.)
Bottom (of initial area) elevation = 1659.000(Ft.)
Difference in elevation = 61.000(Ft.)
Slope = 0.24898 s(percent)= 24.90
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Initial area time of concentration = 6.320 min.
Rainfall intensity = 1.813(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.609
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 1.225(CFS)
Total initial stream area = 1.110(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 158.000 to Point/Station 159.000 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ COMMERCIAL subarea type
Runoff Coefficient = 0.849
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.100; Impervious fraction = 0.900 Time of concentration = 6.32 min.
Rainfall intensity = 1.813(In/Hr) for a 2.0 year storm Subarea runoff = 0.631(CFS) for 0.410(Ac.)
Total runoff = 1.856(CFS) Total area = 1.520(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 158.000 to Point/Station 159.000 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ COMMERCIAL subarea type
Runoff Coefficient = 0.849
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.100; Impervious fraction = 0.900 Time of concentration = 6.32 min.
Rainfall intensity = 1.813(In/Hr) for a 2.0 year storm Subarea runoff = 1.093(CFS) for 0.710(Ac.)
Total runoff = 2.949(CFS) Total area = 2.230(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 160.000 to Point/Station 161.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1650.000(Ft.)
Downstream point/station elevation = 1512.000(Ft.)
Pipe length = 965.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 2.949(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 2.949(CFS)
Normal flow depth in pipe = 4.35(In.)
Flow top width inside pipe = 8.99(In.)
Critical depth could not be calculated.
Pipe flow velocity = 13.95(Ft/s)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Travel time through pipe = 1.15 min.
Time of concentration (TC) = 7.47 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 160.000 to Point/Station 161.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 1
Stream flow area = 2.230(Ac.)
Runoff from this stream = 2.949(CFS)
Time of concentration = 7.47 min.
Rainfall intensity = 1.659(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 162.000 to Point/Station 163.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 945.000(Ft.)
Top (of initial area) elevation = 1717.700(Ft.)
Bottom (of initial area) elevation = 1520.000(Ft.)
Difference in elevation = 197.700(Ft.)
Slope = 0.20921 s(percent)= 20.92
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 11.229 min.
Rainfall intensity = 1.337(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.573
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.700
Decimal fraction soil group C = 0.300
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 63.56
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 3.552(CFS)
Total initial stream area = 4.640(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 163.000 to Point/Station 161.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1513.000(Ft.)
Downstream point/station elevation = 1512.000(Ft.)
Pipe length = 23.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 3.552(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 3.552(CFS)
Normal flow depth in pipe = 5.85(In.)
Flow top width inside pipe = 12.00(In.)
Critical Depth = 9.66(In.)
Pipe flow velocity = 9.35(Ft/s)
Travel time through pipe = 0.04 min.
Time of concentration (TC) = 11.27 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 163.000 to Point/Station 161.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 2
Stream flow area = 4.640(Ac.)
Runoff from this stream = 3.552(CFS)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Time of concentration = 11.27 min.
Rainfall intensity = 1.334(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 2.949 7.47 1.659
2 3.552 11.27 1.334
Largest stream flow has longer time of concentration
Qp = 3.552 + sum of
Qb Ia/Ib
2.949 * 0.804 = 2.372
Qp = 5.924
Total of 2 streams to confluence:
Flow rates before confluence point:
2.949 3.552
Area of streams before confluence:
2.230 4.640
Results of confluence:
Total flow rate = 5.924(CFS)
Time of concentration = 11.270 min.
Effective stream area after confluence = 6.870(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 163.000 to Point/Station 161.000 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.556
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 1.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 61.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Time of concentration = 11.27 min.
Rainfall intensity = 1.334(In/Hr) for a 2.0 year storm Subarea runoff = 0.445(CFS) for 0.600(Ac.)
Total runoff = 6.370(CFS) Total area = 7.470(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 161.000 to Point/Station 128.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1512.000(Ft.)
Downstream point/station elevation = 1509.000(Ft.)
Pipe length = 567.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 6.370(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 6.370(CFS)
Normal flow depth in pipe = 12.56(In.)
Flow top width inside pipe = 16.53(In.)
Critical Depth = 11.71(In.)
Pipe flow velocity = 4.84(Ft/s)
Travel time through pipe = 1.95 min.
Time of concentration (TC) = 13.22 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 161.000 to Point/Station 128.000 Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
**** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 2
Stream flow area = 7.470(Ac.)
Runoff from this stream = 6.370(CFS)
Time of concentration = 13.22 min.
Rainfall intensity = 1.226(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 26.445 14.26 1.178
2 6.370 13.22 1.226
Largest stream flow has longer time of concentration
Qp = 26.445 + sum of
Qb Ia/Ib
6.370 * 0.961 = 6.119
Qp = 32.565
Total of 2 main streams to confluence:
Flow rates before confluence point:
26.445 6.370
Area of streams before confluence:
41.880 7.470
Results of confluence:
Total flow rate = 32.565(CFS)
Time of concentration = 14.262 min.
Effective stream area after confluence = 49.350(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 128.000 to Point/Station 129.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1509.000(Ft.)
Downstream point/station elevation = 1499.100(Ft.)
Pipe length = 333.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 32.565(CFS)
Nearest computed pipe diameter = 24.00(In.)
Calculated individual pipe flow = 32.565(CFS)
Normal flow depth in pipe = 16.76(In.)
Flow top width inside pipe = 22.03(In.)
Critical Depth = 22.74(In.)
Pipe flow velocity = 13.90(Ft/s)
Travel time through pipe = 0.40 min.
Time of concentration (TC) = 14.66 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 128.000 to Point/Station 129.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1
Stream flow area = 49.350(Ac.)
Runoff from this stream = 32.565(CFS)
Time of concentration = 14.66 min.
Rainfall intensity = 1.161(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Process from Point/Station 130.000 to Point/Station 131.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 994.000(Ft.)
Top (of initial area) elevation = 1521.000(Ft.)
Bottom (of initial area) elevation = 1508.600(Ft.)
Difference in elevation = 12.400(Ft.)
Slope = 0.01247 s(percent)= 1.25
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 14.819 min.
Rainfall intensity = 1.154(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.622
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.700
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.300
RI index for soil(AMC 1) = 41.70
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.680(CFS)
Total initial stream area = 2.340(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 131.000 to Point/Station 129.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1499.400(Ft.)
Downstream point/station elevation = 1499.100(Ft.)
Pipe length = 22.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.680(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.680(CFS)
Normal flow depth in pipe = 6.49(In.)
Flow top width inside pipe = 8.07(In.)
Critical Depth = 7.14(In.)
Pipe flow velocity = 4.93(Ft/s)
Travel time through pipe = 0.07 min.
Time of concentration (TC) = 14.89 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 131.000 to Point/Station 129.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2
Stream flow area = 2.340(Ac.)
Runoff from this stream = 1.680(CFS)
Time of concentration = 14.89 min.
Rainfall intensity = 1.151(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 132.000 to Point/Station 133.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 636.000(Ft.)
Top (of initial area) elevation = 1526.500(Ft.)
Bottom (of initial area) elevation = 1519.100(Ft.)
Difference in elevation = 7.400(Ft.)
Slope = 0.01164 s(percent)= 1.16
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 12.569 min.
Rainfall intensity = 1.259(In/Hr) for a 2.0 year storm Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.700
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 1.000
RI index for soil(AMC 1) = 57.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.199(CFS)
Total initial stream area = 1.360(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 133.000 to Point/Station 134.000 **** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION **** ______________________________________________________________________ Top of street segment elevation = 1519.100(Ft.)
End of street segment elevation = 1510.100(Ft.)
Length of street segment = 806.000(Ft.)
Height of curb above gutter flowline = 6.0(In.)
Width of half street (curb to crown) = 18.000(Ft.)
Distance from crown to crossfall grade break = 16.000(Ft.) Slope from gutter to grade break (v/hz) = 0.020
Slope from grade break to crown (v/hz) = 0.020
Street flow is on [1] side(s) of the street
Distance from curb to property line = 10.000(Ft.)
Slope from curb to property line (v/hz) = 0.020
Gutter width = 2.000(Ft.)
Gutter hike from flowline = 2.000(In.)
Manning's N in gutter = 0.0130
Manning's N from gutter to grade break = 0.0130
Manning's N from grade break to crown = 0.0130
Estimated mean flow rate at midpoint of street = 3.498(CFS) Depth of flow = 0.337(Ft.), Average velocity = 2.833(Ft/s) Streetflow hydraulics at midpoint of street travel:
Halfstreet flow width = 10.527(Ft.)
Flow velocity = 2.83(Ft/s)
Travel time = 4.74 min. TC = 17.31 min.
Adding area flow to street
SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.630
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 1) = 45.60
Pervious area fraction = 0.500; Impervious fraction = 0.500 Rainfall intensity = 1.063(In/Hr) for a 2.0 year storm Subarea runoff = 4.501(CFS) for 6.720(Ac.)
Total runoff = 5.701(CFS) Total area = 8.080(Ac.) Street flow at end of street = 5.701(CFS)
Half street flow at end of street = 5.701(CFS)
Depth of flow = 0.385(Ft.), Average velocity = 3.176(Ft/s) Flow width (from curb towards crown)= 12.915(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 134.000 to Point/Station 129.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1499.400(Ft.)
Downstream point/station elevation = 1499.100(Ft.)
Pipe length = 25.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 5.701(CFS)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Nearest computed pipe diameter = 15.00(In.)
Calculated individual pipe flow = 5.701(CFS)
Normal flow depth in pipe = 10.20(In.)
Flow top width inside pipe = 14.00(In.)
Critical Depth = 11.60(In.)
Pipe flow velocity = 6.41(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 17.38 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 134.000 to Point/Station 129.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 1 in normal stream number 3
Stream flow area = 8.080(Ac.)
Runoff from this stream = 5.701(CFS)
Time of concentration = 17.38 min.
Rainfall intensity = 1.061(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 32.565 14.66 1.161
2 1.680 14.89 1.151
3 5.701 17.38 1.061
Largest stream flow has longer or shorter time of concentration Qp = 32.565 + sum of
Qa Tb/Ta
1.680 * 0.984 = 1.654
Qa Tb/Ta
5.701 * 0.844 = 4.810
Qp = 39.029
Total of 3 streams to confluence:
Flow rates before confluence point:
32.565 1.680 5.701
Area of streams before confluence:
49.350 2.340 8.080
Results of confluence:
Total flow rate = 39.029(CFS)
Time of concentration = 14.661 min.
Effective stream area after confluence = 59.770(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 129.000 to Point/Station 135.100 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1499.100(Ft.)
Downstream point/station elevation = 1498.000(Ft.)
Pipe length = 107.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 39.029(CFS)
Nearest computed pipe diameter = 30.00(In.)
Calculated individual pipe flow = 39.029(CFS)
Normal flow depth in pipe = 23.06(In.)
Flow top width inside pipe = 25.30(In.)
Critical Depth = 25.29(In.)
Pipe flow velocity = 9.63(Ft/s)
Travel time through pipe = 0.19 min.
Time of concentration (TC) = 14.85 min.
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 129.000 to Point/Station 135.100 **** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 1
Stream flow area = 59.770(Ac.)
Runoff from this stream = 39.029(CFS)
Time of concentration = 14.85 min.
Rainfall intensity = 1.153(In/Hr)
Program is now starting with Main Stream No. 2
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 136.000 to Point/Station 137.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 616.000(Ft.)
Top (of initial area) elevation = 1515.100(Ft.)
Bottom (of initial area) elevation = 1506.700(Ft.)
Difference in elevation = 8.400(Ft.)
Slope = 0.01364 s(percent)= 1.36
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 12.021 min.
Rainfall intensity = 1.289(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.521
Decimal fraction soil group A = 1.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 16.20
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.202(CFS)
Total initial stream area = 1.790(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 137.000 to Point/Station 138.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1498.900(Ft.)
Downstream point/station elevation = 1498.400(Ft.)
Pipe length = 47.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.202(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.202(CFS)
Normal flow depth in pipe = 5.57(In.)
Flow top width inside pipe = 8.74(In.)
Critical Depth = 6.05(In.)
Pipe flow velocity = 4.18(Ft/s)
Travel time through pipe = 0.19 min.
Time of concentration (TC) = 12.21 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 137.000 to Point/Station 138.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 1
Stream flow area = 1.790(Ac.)
Runoff from this stream = 1.202(CFS)
Time of concentration = 12.21 min.
Rainfall intensity = 1.279(In/Hr)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 139.000 to Point/Station 140.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 701.000(Ft.)
Top (of initial area) elevation = 1512.200(Ft.)
Bottom (of initial area) elevation = 1506.700(Ft.)
Difference in elevation = 5.500(Ft.)
Slope = 0.00785 s(percent)= 0.78
TC = k(0.390)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 14.139 min.
Rainfall intensity = 1.183(In/Hr) for a 2.0 year storm SINGLE FAMILY (1/4 Acre Lot)
Runoff Coefficient = 0.600
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 36.00
Pervious area fraction = 0.500; Impervious fraction = 0.500 Initial subarea runoff = 1.675(CFS)
Total initial stream area = 2.360(Ac.)
Pervious area fraction = 0.500
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 140.000 to Point/Station 138.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1498.600(Ft.)
Downstream point/station elevation = 1498.400(Ft.)
Pipe length = 10.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 1.675(CFS)
Nearest computed pipe diameter = 9.00(In.)
Calculated individual pipe flow = 1.675(CFS)
Normal flow depth in pipe = 5.63(In.)
Flow top width inside pipe = 8.71(In.)
Critical Depth = 7.14(In.)
Pipe flow velocity = 5.76(Ft/s)
Travel time through pipe = 0.03 min.
Time of concentration (TC) = 14.17 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 140.000 to Point/Station 138.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 2 in normal stream number 2
Stream flow area = 2.360(Ac.)
Runoff from this stream = 1.675(CFS)
Time of concentration = 14.17 min.
Rainfall intensity = 1.182(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 1.202 12.21 1.279
2 1.675 14.17 1.182
Largest stream flow has longer time of concentration
Qp = 1.675 + sum of
Qb Ia/Ib
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
1.202 * 0.924 = 1.111
Qp = 2.786
Total of 2 streams to confluence:
Flow rates before confluence point:
1.202 1.675
Area of streams before confluence:
1.790 2.360
Results of confluence:
Total flow rate = 2.786(CFS)
Time of concentration = 14.168 min.
Effective stream area after confluence = 4.150(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 138.000 to Point/Station 135.200 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1498.400(Ft.)
Downstream point/station elevation = 1498.000(Ft.)
Pipe length = 40.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 2.786(CFS)
Nearest computed pipe diameter = 12.00(In.)
Calculated individual pipe flow = 2.786(CFS)
Normal flow depth in pipe = 7.98(In.)
Flow top width inside pipe = 11.33(In.)
Critical Depth = 8.59(In.)
Pipe flow velocity = 5.02(Ft/s)
Travel time through pipe = 0.13 min.
Time of concentration (TC) = 14.30 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 138.000 to Point/Station 135.200 **** CONFLUENCE OF MAIN STREAMS ****
______________________________________________________________________ The following data inside Main Stream is listed:
In Main Stream number: 2
Stream flow area = 4.150(Ac.)
Runoff from this stream = 2.786(CFS)
Time of concentration = 14.30 min.
Rainfall intensity = 1.176(In/Hr)
Program is now starting with Main Stream No. 3
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 146.000 to Point/Station 147.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 1000.000(Ft.)
Top (of initial area) elevation = 1744.000(Ft.)
Bottom (of initial area) elevation = 1579.000(Ft.)
Difference in elevation = 165.000(Ft.)
Slope = 0.16500 s(percent)= 16.50
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 12.044 min.
Rainfall intensity = 1.288(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.538
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Initial subarea runoff = 2.959(CFS)
Total initial stream area = 4.270(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 147.000 to Point/Station 148.000 **** IMPROVED CHANNEL TRAVEL TIME ****
______________________________________________________________________ Upstream point elevation = 1579.000(Ft.)
Downstream point elevation = 1568.000(Ft.)
Channel length thru subarea = 185.000(Ft.)
Channel base width = 0.000(Ft.)
Slope or 'Z' of left channel bank = 1.000
Slope or 'Z' of right channel bank = 1.000
Estimated mean flow rate at midpoint of channel = 3.196(CFS) Manning's 'N' = 0.013
Maximum depth of channel = 1.500(Ft.)
Flow(q) thru subarea = 3.196(CFS)
Depth of flow = 0.576(Ft.), Average velocity = 9.644(Ft/s) Channel flow top width = 1.151(Ft.)
Flow Velocity = 9.64(Ft/s)
Travel time = 0.32 min.
Time of concentration = 12.36 min.
Sub-Channel No. 1 Critical depth = 0.914(Ft.)
' ' ' Critical flow top width = 1.828(Ft.) ' ' ' Critical flow velocity= 3.826(Ft/s) ' ' ' Critical flow area = 0.836(Sq.Ft) Adding area flow to channel
UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.437
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 49.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.270(In/Hr) for a 2.0 year storm Subarea runoff = 0.422(CFS) for 0.760(Ac.)
Total runoff = 3.381(CFS) Total area = 5.030(Ac.) Depth of flow = 0.588(Ft.), Average velocity = 9.781(Ft/s) Sub-Channel No. 1 Critical depth = 0.938(Ft.)
' ' ' Critical flow top width = 1.875(Ft.) ' ' ' Critical flow velocity= 3.847(Ft/s) ' ' ' Critical flow area = 0.879(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 147.000 to Point/Station 148.000 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.535
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Time of concentration = 12.36 min.
Rainfall intensity = 1.270(In/Hr) for a 2.0 year storm Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Subarea runoff = 1.631(CFS) for 2.400(Ac.)
Total runoff = 5.012(CFS) Total area = 7.430(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 148.000 to Point/Station 149.000 **** IMPROVED CHANNEL TRAVEL TIME ****
______________________________________________________________________ Upstream point elevation = 1568.000(Ft.)
Downstream point elevation = 1560.000(Ft.)
Channel length thru subarea = 220.000(Ft.)
Channel base width = 0.000(Ft.)
Slope or 'Z' of left channel bank = 1.000
Slope or 'Z' of right channel bank = 1.000
Estimated mean flow rate at midpoint of channel = 5.147(CFS) Manning's 'N' = 0.013
Maximum depth of channel = 1.500(Ft.)
Flow(q) thru subarea = 5.147(CFS)
Depth of flow = 0.755(Ft.), Average velocity = 9.035(Ft/s) Channel flow top width = 1.510(Ft.)
Flow Velocity = 9.04(Ft/s)
Travel time = 0.41 min.
Time of concentration = 12.77 min.
Sub-Channel No. 1 Critical depth = 1.102(Ft.)
' ' ' Critical flow top width = 2.203(Ft.) ' ' ' Critical flow velocity= 4.242(Ft/s) ' ' ' Critical flow area = 1.213(Sq.Ft) Adding area flow to channel
UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.433
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 49.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.249(In/Hr) for a 2.0 year storm Subarea runoff = 0.217(CFS) for 0.400(Ac.)
Total runoff = 5.229(CFS) Total area = 7.830(Ac.) Depth of flow = 0.759(Ft.), Average velocity = 9.071(Ft/s) Sub-Channel No. 1 Critical depth = 1.109(Ft.)
' ' ' Critical flow top width = 2.219(Ft.) ' ' ' Critical flow velocity= 4.249(Ft/s) ' ' ' Critical flow area = 1.231(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 149.000 to Point/Station 150.000 **** IMPROVED CHANNEL TRAVEL TIME ****
______________________________________________________________________ Upstream point elevation = 1560.000(Ft.)
Downstream point elevation = 1555.000(Ft.)
Channel length thru subarea = 190.000(Ft.)
Channel base width = 0.000(Ft.)
Slope or 'Z' of left channel bank = 1.000
Slope or 'Z' of right channel bank = 1.000
Estimated mean flow rate at midpoint of channel = 5.531(CFS) Manning's 'N' = 0.013
Maximum depth of channel = 1.500(Ft.)
Flow(q) thru subarea = 5.531(CFS)
Depth of flow = 0.824(Ft.), Average velocity = 8.148(Ft/s) Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Channel flow top width = 1.648(Ft.)
Flow Velocity = 8.15(Ft/s)
Travel time = 0.39 min.
Time of concentration = 13.16 min.
Sub-Channel No. 1 Critical depth = 1.141(Ft.)
' ' ' Critical flow top width = 2.281(Ft.) ' ' ' Critical flow velocity= 4.251(Ft/s) ' ' ' Critical flow area = 1.301(Sq.Ft) Adding area flow to channel
UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.430
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 49.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.229(In/Hr) for a 2.0 year storm Subarea runoff = 0.534(CFS) for 1.010(Ac.)
Total runoff = 5.763(CFS) Total area = 8.840(Ac.) Depth of flow = 0.837(Ft.), Average velocity = 8.232(Ft/s) Sub-Channel No. 1 Critical depth = 1.156(Ft.)
' ' ' Critical flow top width = 2.313(Ft.) ' ' ' Critical flow velocity= 4.310(Ft/s) ' ' ' Critical flow area = 1.337(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 149.000 to Point/Station 150.000 **** SUBAREA FLOW ADDITION ****
______________________________________________________________________ UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.528
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 60.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Time of concentration = 13.16 min.
Rainfall intensity = 1.229(In/Hr) for a 2.0 year storm Subarea runoff = 2.206(CFS) for 3.400(Ac.)
Total runoff = 7.968(CFS) Total area = 12.240(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 150.000 to Point/Station 151.000 **** IMPROVED CHANNEL TRAVEL TIME ****
______________________________________________________________________ Upstream point elevation = 1555.000(Ft.)
Downstream point elevation = 1536.000(Ft.)
Channel length thru subarea = 330.000(Ft.)
Channel base width = 0.000(Ft.)
Slope or 'Z' of left channel bank = 1.000
Slope or 'Z' of right channel bank = 1.000
Estimated mean flow rate at midpoint of channel = 8.131(CFS) Manning's 'N' = 0.013
Maximum depth of channel = 1.500(Ft.)
Flow(q) thru subarea = 8.131(CFS)
Depth of flow = 0.822(Ft.), Average velocity = 12.034(Ft/s) Channel flow top width = 1.644(Ft.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Flow Velocity = 12.03(Ft/s)
Travel time = 0.46 min.
Time of concentration = 13.62 min.
Sub-Channel No. 1 Critical depth = 1.328(Ft.)
' ' ' Critical flow top width = 2.656(Ft.) ' ' ' Critical flow velocity= 4.610(Ft/s) ' ' ' Critical flow area = 1.764(Sq.Ft) Adding area flow to channel
UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.426
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 1.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 49.80
Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 1.207(In/Hr) for a 2.0 year storm Subarea runoff = 0.257(CFS) for 0.500(Ac.)
Total runoff = 8.225(CFS) Total area = 12.740(Ac.) Depth of flow = 0.826(Ft.), Average velocity = 12.069(Ft/s) Sub-Channel No. 1 Critical depth = 1.328(Ft.)
' ' ' Critical flow top width = 2.656(Ft.) ' ' ' Critical flow velocity= 4.663(Ft/s) ' ' ' Critical flow area = 1.764(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 151.000 to Point/Station 152.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1534.000(Ft.)
Downstream point/station elevation = 1533.000(Ft.)
Pipe length = 104.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 8.225(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 8.225(CFS)
Normal flow depth in pipe = 12.16(In.)
Flow top width inside pipe = 16.85(In.)
Critical Depth = 13.33(In.)
Pipe flow velocity = 6.47(Ft/s)
Travel time through pipe = 0.27 min.
Time of concentration (TC) = 13.88 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 151.000 to Point/Station 152.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 1
Stream flow area = 12.740(Ac.)
Runoff from this stream = 8.225(CFS)
Time of concentration = 13.88 min.
Rainfall intensity = 1.195(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 153.000 to Point/Station 152.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 727.000(Ft.)
Top (of initial area) elevation = 1707.000(Ft.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Bottom (of initial area) elevation = 1537.000(Ft.)
Difference in elevation = 170.000(Ft.)
Slope = 0.23384 s(percent)= 23.38
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 9.888 min.
Rainfall intensity = 1.430(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.625
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.500
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 0.500
RI index for soil(AMC 1) = 67.90
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 3.037(CFS)
Total initial stream area = 3.400(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 153.000 to Point/Station 152.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 2
Stream flow area = 3.400(Ac.)
Runoff from this stream = 3.037(CFS)
Time of concentration = 9.89 min.
Rainfall intensity = 1.430(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 8.225 13.88 1.195
2 3.037 9.89 1.430
Largest stream flow has longer time of concentration
Qp = 8.225 + sum of
Qb Ia/Ib
3.037 * 0.835 = 2.537
Qp = 10.763
Total of 2 streams to confluence:
Flow rates before confluence point:
8.225 3.037
Area of streams before confluence:
12.740 3.400
Results of confluence:
Total flow rate = 10.763(CFS)
Time of concentration = 13.883 min.
Effective stream area after confluence = 16.140(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 152.000 to Point/Station 154.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1533.000(Ft.)
Downstream point/station elevation = 1519.500(Ft.)
Pipe length = 440.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 10.763(CFS)
Nearest computed pipe diameter = 15.00(In.)
Calculated individual pipe flow = 10.763(CFS)
Normal flow depth in pipe = 11.70(In.)
Flow top width inside pipe = 12.43(In.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Critical depth could not be calculated.
Pipe flow velocity = 10.49(Ft/s)
Travel time through pipe = 0.70 min.
Time of concentration (TC) = 14.58 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 152.000 to Point/Station 154.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 1
Stream flow area = 16.140(Ac.)
Runoff from this stream = 10.763(CFS)
Time of concentration = 14.58 min.
Rainfall intensity = 1.164(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 155.000 to Point/Station 156.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 320.000(Ft.)
Top (of initial area) elevation = 1575.000(Ft.)
Bottom (of initial area) elevation = 1528.000(Ft.)
Difference in elevation = 47.000(Ft.)
Slope = 0.14688 s(percent)= 14.69
TC = k(0.710)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 10.470 min.
Rainfall intensity = 1.387(In/Hr) for a 2.0 year storm UNDEVELOPED (fair cover) subarea
Runoff Coefficient = 0.625
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 0.000
Decimal fraction soil group D = 1.000
RI index for soil(AMC 1) = 68.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.477(CFS)
Total initial stream area = 0.550(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 156.000 to Point/Station 154.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1528.000(Ft.)
Downstream point/station elevation = 1519.500(Ft.)
Pipe length = 36.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 0.477(CFS)
Nearest computed pipe diameter = 6.00(In.)
Calculated individual pipe flow = 0.477(CFS)
Normal flow depth in pipe = 1.70(In.)
Flow top width inside pipe = 5.41(In.)
Critical Depth = 4.22(In.)
Pipe flow velocity = 10.44(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 10.53 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 156.000 to Point/Station 154.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 2
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Stream flow area = 0.550(Ac.)
Runoff from this stream = 0.477(CFS)
Time of concentration = 10.53 min.
Rainfall intensity = 1.383(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 10.763 14.58 1.164
2 0.477 10.53 1.383
Largest stream flow has longer time of concentration
Qp = 10.763 + sum of
Qb Ia/Ib
0.477 * 0.841 = 0.401
Qp = 11.164
Total of 2 streams to confluence:
Flow rates before confluence point:
10.763 0.477
Area of streams before confluence:
16.140 0.550
Results of confluence:
Total flow rate = 11.164(CFS)
Time of concentration = 14.582 min.
Effective stream area after confluence = 16.690(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 154.000 to Point/Station 157.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1519.500(Ft.)
Downstream point/station elevation = 1509.800(Ft.)
Pipe length = 660.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 11.164(CFS)
Nearest computed pipe diameter = 18.00(In.)
Calculated individual pipe flow = 11.164(CFS)
Normal flow depth in pipe = 13.05(In.)
Flow top width inside pipe = 16.07(In.)
Critical Depth = 15.34(In.)
Pipe flow velocity = 8.13(Ft/s)
Travel time through pipe = 1.35 min.
Time of concentration (TC) = 15.94 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 154.000 to Point/Station 157.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 1
Stream flow area = 16.690(Ac.)
Runoff from this stream = 11.164(CFS)
Time of concentration = 15.94 min.
Rainfall intensity = 1.111(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 158.000 to Point/Station 159.000 **** INITIAL AREA EVALUATION ****
______________________________________________________________________ Initial area flow distance = 442.000(Ft.)
Top (of initial area) elevation = 1640.000(Ft.)
Bottom (of initial area) elevation = 1535.000(Ft.)
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification
Section 3
Difference in elevation = 105.000(Ft.)
Slope = 0.23756 s(percent)= 23.76
TC = k(0.530)*[(length^3)/(elevation change)]^0.2
Initial area time of concentration = 8.078 min.
Rainfall intensity = 1.592(In/Hr) for a 2.0 year storm UNDEVELOPED (poor cover) subarea
Runoff Coefficient = 0.676
Decimal fraction soil group A = 0.000
Decimal fraction soil group B = 0.000
Decimal fraction soil group C = 1.000
Decimal fraction soil group D = 0.000
RI index for soil(AMC 1) = 71.60
Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 2.205(CFS)
Total initial stream area = 2.050(Ac.)
Pervious area fraction = 1.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 159.000 to Point/Station 157.000 **** PIPEFLOW TRAVEL TIME (Program estimated size) **** ______________________________________________________________________ Upstream point/station elevation = 1533.000(Ft.)
Downstream point/station elevation = 1509.800(Ft.)
Pipe length = 65.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow = 2.205(CFS)
Nearest computed pipe diameter = 6.00(In.)
Calculated individual pipe flow = 2.205(CFS)
Normal flow depth in pipe = 3.55(In.)
Flow top width inside pipe = 5.90(In.)
Critical depth could not be calculated.
Pipe flow velocity = 18.22(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 8.14 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 159.000 to Point/Station 157.000 **** CONFLUENCE OF MINOR STREAMS ****
______________________________________________________________________ Along Main Stream number: 3 in normal stream number 2
Stream flow area = 2.050(Ac.)
Runoff from this stream = 2.205(CFS)
Time of concentration = 8.14 min.
Rainfall intensity = 1.586(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr)
1 11.164 15.94 1.111
2 2.205 8.14 1.586
Largest stream flow has longer time of concentration
Qp = 11.164 + sum of
Qb Ia/Ib
2.205 * 0.700 = 1.544
Qp = 12.708
Total of 2 streams to confluence:
Flow rates before confluence point:
11.164 2.205
Area of streams before confluence:
16.690 2.050
Results of confluence:
Preliminary Hydrology Analysis – Golden Meadows – Tract 31194 – Major Modification