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HomeMy WebLinkAboutDrainage Report 102225CASTLE VALLEY PH2 SUBDIVISION CITY OF LITTLE ROCK, PULASKI COUNTY, ARKANSAS DRAINAGE REPORT October 2025 Vicinity Map Owner & Developer By: 129 N. Main Street Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com Engineering Certification Kazi Tamzidul Islam, Registered Professional Engineer No. 20876 in the State of Arkansas, hereby certify that this drainage report was conducted by me or directly under my supervision and attesting to the accuracy of the information within this report. 10-22-2025 Table of Contents- Drainage Summary Pre Development Area & Calculation Post Development Area & Calculation Ditch Details Hydrograph Summary Report Precipitation Data of NOAA DRAINAGE SUMMARY PROJECT TITLE 8500 CASTLE VALLEY ROAD PROJECT PROPERTY OWNER JACOB POWELL PROJECT LOCATION A Subdivision in The City of Little Rock, Pulaski County, Arkansas PROJECT DESCRIPTION The proposed development is on Castle Valley Road. The total development site area is 9.21 acres. DRAINAGE ANALYSIS On Site Drainage- Rational method was used to determine the existing and proposed flows from proposed site. There will be One detention ponds to detain water from this development. Detailed drainage calculations considering the future expected development have been conducted to determine the required detention volumes and culvert dimensions as required. Summary of the calculations are below: North West Detention Pond • A detention pond has been proposed on the South side of the property. • Pre-development area – A 5.46 acres. • Pre-development area – B 9.65 acres. • Post-development area – 15.10 acres. • Considering the existing condition, pre-development-A runoff coefficient 0.47. • pre-development-B runoff coefficient 0.66. • Post-development cumulative runoff coefficient 0.49. • Bottom elevation of detention facility is 298.50’. • One 18’’ RCP with 1.00% slope is proposed for outflow culvert. Peak flows for Pre and post development phase of onsite area have been tabulated below- Pre-development Dev. Generated Post-dev. After deten- tion Peak Flow (cfs) Peak Flow (cfs) Peak Flow (cfs) 2-Year 34.15 31.85 4.6 5-Year 40.69 37.98 6.737 10- Year 45.85 42.82 8.99 25- Year 52.61 49.12 13.61 50- Year 57.56 53.73 17.71 100- Year 62.43 58.26 21.72 CONCLUSION From the drainage calculation, it is seen that there is decrease in flow for all storm events due to the proposed detention pond. Hydrograph Summary Report SOUTH DETENTION N02°15'02"E 871.14'N02°32'46"E 9.75'S88°37'49"E 431.47'S45°19'05"W 130.14'S03°21'28"W 125.52'N84°44'25"E 30.01'S28°4 1 ' 36 "E 4 3 . 1 7 'S01°33'15"W 642.78'S12°28'09"W 122.29'N88°33'14"W 457.98'N02°09'42"E 267.13'S87°47'08"E 33.66'S87°36'49"E 119.81' S89°36'04"E 160.17'68.60'69.48'69.79'70.52'69.51'69.54'70.77'70.10'70.13'69.61'136.52'34.93'151.03'9.14'9.75'189.58'14.77'118.14'130.14'67.03'58.49'58.49'30.01'43.17 '47.26'70.53'69.88'70.00'69.96'69.89'70.17'69.95'70.24'34.90'35.40'86.89'118.69'58.63'280.66'267.13'153.47' DETENTION AREA 1.52 ACRES 66324 Sq. Ft.1.64'183.05'70.00'70.00'70.00'70.08'69.92'70.00'51.80'32.33'12.17'28 0.26 ACRES 11209 Sq. Ft. 27 0.23 ACRES 9994 Sq. Ft. 26 0.23 ACRES 10105 Sq. Ft. 24 0.23 ACRES 10022 Sq. Ft. 21 0.23 ACRES 9871 Sq. Ft. 20 0.23 ACRES 9820 Sq. Ft. 19 0.23 ACRES 9910 Sq. Ft. 6 0.21 ACRES 9073 Sq. Ft. 2 0.21 ACRES 9068 Sq. Ft. 3 0.21 ACRES 9069 Sq. Ft. 7 0.21 ACRES 9055 Sq. Ft. 15 0.42 ACRES 18288 Sq. Ft. 8 0.20 ACRES 8631 Sq. Ft. 9 0.17 ACRES 7463 Sq. Ft. 11 0.16 ACRES 6979 Sq. Ft. 23 0.23 ACRES 9958 Sq. Ft. 18 0.26 ACRES 11184 Sq. Ft. 12 0.21 ACRES 9302 Sq. Ft. 5 0.21 ACRES 9149 Sq. Ft. 13 0.29 ACRES 12827 Sq. Ft. 4 0.21 ACRES 9095 Sq. Ft. 1 0.21 ACRES 9302 Sq. Ft. 16 0.21 ACRES 9025 Sq. Ft. N88°00'36"W 138.34'70.00'70.00'70.00'70.00'70.00'70.00'70.00'77.22'58.64'47.14'50.28'22.33'44.50'N87°53'49"W 144.43' N87°58'05"W 143.19' S88°02'14"E 142.79' N87°59'33"W 141.95' N87°58'23"W 140.71' N87°55'29"W 140.09' N88°08'01"W 144.50' N87°47'19"W 130.18' S88°00'11"E 129.95' S87°04'55"E 131.36' S87°41'41"E 130.37' S87°55'24"E 129.69' S88°12'24"E 128.99'S2°03'41"W 96.01'S87°51'20"E 114.00' S87°47'17"E 101.98' S87°55'56"E 92.00' N81°50'44"E 1 0 9 . 7 1 ' N 4 9 ° 4 3 ' 0 3 "W 1 3 0 . 0 0 ' S88°03'18"E 130.41' N6 1 ° 3 8 ' 0 8 " W 6 8 . 7 3 '70.38'S87°57'48"E 130.60' 22 0.23 ACRES 9912 Sq. Ft. N87°58'33"W 141.33' 25 0.23 ACRES 10041 Sq. Ft. N87°59'22"W 143.81'17.63'10 0.16 ACRES 7122 Sq. Ft. S87°47'17"E 101.98' S87°42'44"E 101.52' 14 0.38 ACRES 16393 Sq. Ft.S2°03'41"W 96.01'N54° 0 8' 20" E 1 91. 1 2'70.00'17 0.18 ACRES 7718 Sq. Ft. N81°50'44"E 1 0 9 . 7 1 ' S87°55'55"E 116.06'Overland FlowShallow Con FlowChannel FlowPRE DEVELOPMENT AREA-B 9.65 ACRES PRE DEVELOPMENT AREA-A 5.46 ACRES Ch a n n e l F l o w - 2Channel F low-1 OverLand F l o w Shal low Con FLowBASIS OF BEARING:GRID NORTH, ARKANSASCOORDINATE SYSTEM, NORTH ZONEBY GPS OBSERVATIONVICINITY MAP: PROJECT LOCATION FOR USE AND BENEFIT OF: 129 N. Main Street, Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com C.A.D. BY:DRAWING NUMBER:DATE: SHEET: REVISED:E:\HOPE CONSULTING\0.OFFICE PROJECTS\ASSIGNED PROJECTS]\25-0107 JACOB POWELL-CASTLE VALLEY ROAD\WORKING\T02\CORRIDOR\FINAL 7\SAJ_MH_ABIR_08.04.2025_-25-0107_JACOB POWELL.DWG CHECKED BY: SCALE: A SUBDIVISION IN PULASKI COUNTY, ARKANSAS CASTLE VALLEY SUBDIVISION. JACOB POWELL 25-0107 500 01S 13W 0 06 340 62 1664 08/25/2025 ## C-9.0 PRE DEVELOPMENT DRAINAGE AREA MAP 1' = 70"CERTIFICATE O F AUTHORI Z ATIONNo. 1931 HOPE CONSULTING, INC. ARKAN S A S N02°15'02"E 871.14'N02°32'46"E 9.75'S88°37'49"E 431.47'S45°19'05"W 130.14'S03°21'28"W 125.52'N84°44'25"E 30.01'S28°4 1 ' 36 "E 4 3 . 17 'S01°33'15"W 642.78'S12°28'09"W 122.29'N88°33'14"W 457.98'N02°09'42"E 267.13'S87°47'08"E 33.66'S87°36'49"E 119.81' S89°36'04"E 160.17'68.60'69.48'69.79'70.52'69.51'69.54'70.77'70.10'70.13'69.61'136.52'34.93'151.03'9.14'9.75'189.58'14.77'118.14'130.14'67.03'58.49'58.49'30.01'43.17 '47.26'70.53'69.88'70.00'69.96'69.89'70.17'69.95'70.24'34.90'35.40'86.89'118.69'58.63'280.66'267.13'153.47' DETENTION AREA 1.52 ACRES 66324 Sq. Ft.1.64'183.05'70.00'70.00'70.00'70.08'69.92'70.00'51.80'32.33'12.17'28 0.26 ACRES 11209 Sq. Ft. 27 0.23 ACRES 9994 Sq. Ft. 26 0.23 ACRES 10105 Sq. Ft. 24 0.23 ACRES 10022 Sq. Ft. 21 0.23 ACRES 9871 Sq. Ft. 20 0.23 ACRES 9820 Sq. Ft. 19 0.23 ACRES 9910 Sq. Ft. 6 0.21 ACRES 9073 Sq. Ft. 2 0.21 ACRES 9068 Sq. Ft. 3 0.21 ACRES 9069 Sq. Ft. 7 0.21 ACRES 9055 Sq. Ft. 15 0.42 ACRES 18288 Sq. Ft. 8 0.20 ACRES 8631 Sq. Ft. 9 0.17 ACRES 7463 Sq. Ft. 11 0.16 ACRES 6979 Sq. Ft. 23 0.23 ACRES 9958 Sq. Ft. 18 0.26 ACRES 11184 Sq. Ft. 12 0.21 ACRES 9302 Sq. Ft. 5 0.21 ACRES 9149 Sq. Ft. 13 0.29 ACRES 12827 Sq. Ft. 4 0.21 ACRES 9095 Sq. Ft. 1 0.21 ACRES 9302 Sq. Ft. 16 0.21 ACRES 9025 Sq. Ft. N88°00'36"W 138.34'70.00'70.00'70.00'70.00'70.00'70.00'70.00'77.22'58.64'47.14'50.28'22.33'44.50'N87°53'49"W 144.43' N87°58'05"W 143.19' S88°02'14"E 142.79' N87°59'33"W 141.95' N87°58'23"W 140.71' N87°55'29"W 140.09' N88°08'01"W 144.50' N87°47'19"W 130.18' S88°00'11"E 129.95' S87°04'55"E 131.36' S87°41'41"E 130.37' S87°55'24"E 129.69' S88°12'24"E 128.99'S2°03'41"W 96.01'S87°51'20"E 114.00' S87°47'17"E 101.98' S87°55'56"E 92.00' N81°50'44"E 1 0 9 . 7 1 ' N 4 9 ° 4 3 ' 0 3 "W 1 3 0 . 0 0 ' S88°03'18"E 130.41' N6 1 ° 3 8 ' 0 8 " W 6 8 . 7 3 '70.38'S87°57'48"E 130.60' 22 0.23 ACRES 9912 Sq. Ft. N87°58'33"W 141.33' 25 0.23 ACRES 10041 Sq. Ft. N87°59'22"W 143.81'17.63'10 0.16 ACRES 7122 Sq. Ft. S87°47'17"E 101.98' S87°42'44"E 101.52' 14 0.38 ACRES 16393 Sq. Ft.S2°03'41"W 96.01'N54° 0 8'2 0" E 19 1. 1 2'70.00'17 0.18 ACRES 7718 Sq. Ft. N81°50'44"E 1 0 9 . 7 1 ' S87°55'55"E 116.06' Ov e r l a n d F l o w Shallow Con FlowChannel Flow-3Pipe FlowCh a n n e l F l o w - 2 Ch a n n e l F l o w - 1 POST DEVELOPMENT AREA 15.10 ACRES 32533029930030130230 5 31 0 31 5 3 2 0 325 330 320325310315320310 315320325330 BASIS OF BEARING:GRID NORTH, ARKANSASCOORDINATE SYSTEM, NORTH ZONEBY GPS OBSERVATIONVICINITY MAP: PROJECT LOCATION FOR USE AND BENEFIT OF: 129 N. Main Street, Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com C.A.D. BY:DRAWING NUMBER:DATE: SHEET: REVISED:E:\HOPE CONSULTING\0.OFFICE PROJECTS\ASSIGNED PROJECTS]\25-0107 JACOB POWELL-CASTLE VALLEY ROAD\WORKING\T02\CORRIDOR\FINAL 7\SAJ_MH_ABIR_08.04.2025_-25-0107_JACOB POWELL.DWG CHECKED BY: SCALE: A SUBDIVISION IN PULASKI COUNTY, ARKANSAS CASTLE VALLEY SUBDIVISION. JACOB POWELL 25-0107 500 01S 13W 0 06 340 62 1664 08/25/2025 ## C-9.1 POST DEVELOPMENT DRAINAGE AREA MAP 1' = 30"CERTIFICATE O F AUTHOR I Z ATIONNo. 1931 HOPE CONSULTING, INC. ARKAN S A S 3 0 0 300 3 0 5310315320 320320325 325325330335 340 DETENTION AREA 1.52 ACRES 66324 Sq. Ft. 6 0.21 ACRES 9073 Sq. Ft. 2 0.21 ACRES 9068 Sq. Ft. 3 0.21 ACRES 9069 Sq. Ft. 7 0.21 ACRES 9055 Sq. Ft. 8 0.20 ACRES 8631 Sq. Ft. 9 0.17 ACRES 7463 Sq. Ft. 11 0.16 ACRES 6979 Sq. Ft. 12 0.21 ACRES 9302 Sq. Ft. 5 0.21 ACRES 9149 Sq. Ft. 13 0.29 ACRES 12827 Sq. Ft. 4 0.21 ACRES 9095 Sq. Ft. 1 0.21 ACRES 9302 Sq. Ft. 10 0.16 ACRES 7122 Sq. Ft. 143' OF 18" HDPE @ 11.44% CB-5 7+45.92 Storm RIM:307.47 INV IN:301.50 N INV IN:302.02 E INV OUT:301.00 S 117' OF 18" HDPE @ 1.53%42' OF 18" RCP @ 1 . 4 6 %397' OF 18" HDPE @ 3.35%91' OF 18" HDPE @ 0.50%43' OF 18" HDPE @ 0.50%325330299300301302310 315320325330 SPILLWAY FL 298.5' 48' OF 24" RCP PIPE FL 296.26' FL 298.2' FL 298.5' 32' LF OF 18" RCP @1.0% CB-6 8+62.78 Storm RIM:304.77 INV IN:299.21 N INV IN:299.73 E INV OUT:299.11 W DITCH-1 0+001+00 2+003+004+005+006+007+008+00 9+009+05 32' OF 18" RCP @ 1.00% 32' OF 18" RCP @ 1.00% 33' OF 18" RCP @ 1.00%216' OF 18" HDPE @ 1.93%Area : 17.38 BASIS OF BEARING:GRID NORTH, ARKANSASCOORDINATE SYSTEM, NORTH ZONEBY GPS OBSERVATIONVICINITY MAP: PROJECT LOCATION FOR USE AND BENEFIT OF: 129 N. Main Street, Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com C.A.D. BY:DRAWING NUMBER:DATE: SHEET: REVISED:E:\HOPE CONSULTING\0.OFFICE PROJECTS\ASSIGNED PROJECTS]\25-0107 JACOB POWELL-CASTLE VALLEY ROAD\WORKING\T02\CORRIDOR\FINAL 7\SAJ_MH_ABIR_08.04.2025_-25-0107_JACOB POWELL.DWG CHECKED BY: SCALE: A SUBDIVISION IN PULASKI COUNTY, ARKANSAS CASTLE VALLEY SUBDIVISION. JACOB POWELL 25-0107 500 01S 13W 0 06 340 62 1664 08/25/2025 ## C-9.2 DITCH DETAILS 1' = 30"CERTIFICATE O F AUTHORI Z ATIONNo. 1931 HOPE CONSULTING, INC. ARKAN S A SHDPE RCP 12' WIDE 2' DEEP DITCH SECTION S88°37'49"E 431.47'S45°19'05"W 130.14'S03°21'28"W 125.52'N84°44'25"E 30.01'S28°4 1 ' 36 "E 4 3 . 17 ' 189.58'14.77'118.14'130.14'67.03'58.49'58.49'30.01'43.17 ' 15 0.42 ACRES 18288 Sq. Ft. 16 0.21 ACRES 9025 Sq. Ft. N81°50'44"E 1 0 9 . 7 1 ' N6 1 ° 3 8 ' 0 8 " W 6 8 . 7 3 ' 14 0.38 ACRES 16393 Sq. Ft. N54° 0 8' 2 0" E 1 9 1. 1 2' 17 0.18 ACRES 7718 Sq. Ft. N81°50'44"E 1 0 9 . 7 1 ' S87°55'55"E 116.06' DITCH-2 DITCH-2 DITCH-2 DITCH-2 N84°44'25"E 30.01'S28°4 1 ' 36 "E 4 3 . 17 'S01°33'15"W 642.78'58.49'58.49'30.01'43.17 '47.26'70.53'69.88'70.00'69.96'21 0.23 ACRES 9871 Sq. Ft. 20 0.23 ACRES 9820 Sq. Ft. 19 0.23 ACRES 9910 Sq. Ft. 18 0.26 ACRES 11184 Sq. Ft. N87°59'33"W 141.95' N87°58'23"W 140.71' N87°55'29"W 140.09' N88°08'01"W 144.50' N81°50'44"E 1 0 9 . 7 1 ' 22 0.23 ACRES 9912 Sq. Ft. N87°58'33"W 141.33' 0.18 ACRES 7718 Sq. Ft. N81°50'44"E 1 0 9 . 7 1 ' DITCH-3 DITCH-3 DITCH-3 DITCH-2 BASIS OF BEARING:GRID NORTH, ARKANSASCOORDINATE SYSTEM, NORTH ZONEBY GPS OBSERVATIONVICINITY MAP: PROJECT LOCATION FOR USE AND BENEFIT OF: 129 N. Main Street, Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com C.A.D. BY:DRAWING NUMBER:DATE: SHEET: REVISED:E:\HOPE CONSULTING\0.OFFICE PROJECTS\ASSIGNED PROJECTS]\25-0107 JACOB POWELL-CASTLE VALLEY ROAD\WORKING\T02\CORRIDOR\FINAL 7\SAJ_MH_ABIR_08.04.2025_-25-0107_JACOB POWELL.DWG CHECKED BY: SCALE: A SUBDIVISION IN PULASKI COUNTY, ARKANSAS CASTLE VALLEY SUBDIVISION. JACOB POWELL 25-0107 500 01S 13W 0 06 340 62 1664 08/25/2025 ## C-9.2 DITCH DETAILS 1' = 30"CERTIFICATE O F AUTHORI Z ATIONNo. 1931 HOPE CONSULTING, INC. ARKAN S A SHDPE RCP 3' WIDE 0.5' DEEP DITCH SECTION 2 & 3 DITCH- 2 PLAN DITCH- 3 PLAN DETENTION AREA 1.52 ACRES 66324 Sq. Ft. 28 0.26 ACRES 11209 Sq. Ft. 27 0.23 ACRES 9994 Sq. Ft. 26 0.23 ACRES 10105 Sq. Ft. 24 0.23 ACRES 10022 Sq. Ft. 21 0.23 ACRES 9871 Sq. Ft. 20 0.23 ACRES 9820 Sq. Ft. 19 0.23 ACRES 9910 Sq. Ft. 6 0.21 ACRES 9073 Sq. Ft. 2 0.21 ACRES 9068 Sq. Ft. 3 0.21 ACRES 9069 Sq. Ft. 7 0.21 ACRES 9055 Sq. Ft. 15 0.42 ACRES 18288 Sq. Ft. 8 0.20 ACRES 8631 Sq. Ft. 9 0.17 ACRES 7463 Sq. Ft. 11 0.16 ACRES 6979 Sq. Ft. 23 0.23 ACRES 9958 Sq. Ft. 18 0.26 ACRES 11184 Sq. Ft. 12 0.21 ACRES 9302 Sq. Ft. 5 0.21 ACRES 9149 Sq. Ft. 13 0.29 ACRES 12827 Sq. Ft. 4 0.21 ACRES 9095 Sq. Ft. 1 0.21 ACRES 9302 Sq. Ft. 16 0.21 ACRES 9025 Sq. Ft. 22 0.23 ACRES 9912 Sq. Ft. 25 0.23 ACRES 10041 Sq. Ft. 10 0.16 ACRES 7122 Sq. Ft. 14 0.38 ACRES 16393 Sq. Ft. 17 0.18 ACRES 7718 Sq. Ft.8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S 8S 8S 8S 8S 143' OF 18" HDPE @ 11.44% CB-01 0+00.00 Storm RIM:326.67 INV IN:320.36 W INV OUT:320.26 S CB-02 0+42.85 Storm RIM:326.10 INV IN:320.05 N INV OUT:319.95 E DITCH-2 DITCH-2 DITCH-3 DITCH-3 DITCH-3 CB-10 0+00.00 Storm RIM:305.12 INV OUT:300.05 W CB-9 0+00.00 Storm RIM:307.47 INV OUT:302.34 W CB-5 7+45.92 Storm RIM:307.47 INV IN:301.50 N INV IN:302.02 E INV OUT:301.40 S CB-08 0+00.00 Storm RIM:320.33 INV OUT:315.25 W CB-4 3+49.30 Storm RIM:320.31 INV IN:314.92 E INV IN:315.29 N INV OUT:314.79 S 117' OF 18" HDPE @ 1.88%42' OF 18" RCP @ 1 . 4 6 %397' OF 18" HDPE @ 3.35%91' OF 18" HDPE @ 0.50%43' OF 18" HDPE @ 0.50%CB-03 1+33.60 Storm RIM:324.28 INV IN:319.50 W INV IN:318.89 E INV OUT:318.79 S DITCH-2 SPILLWAY DITCH-2 48' OF 24" RCP PIPE FL 296.26' FL 298.2' FL 298.5' CB-6 8+62.78 Storm RIM:304.77 INV IN:299.21 N INV IN:299.73 E INV OUT:299.11 W DITCH-1 PROPOSED INLET AREA-CB-03 0.79 ACRES PROPOSED INLET AREA-CB-04 0.7 ACRES PROPOSED INLET AREA-CB-05 1.02 ACRES PROPOSED INLET AREA-CB-06 0.67 ACRES PROPOSED INLET AREA-CB-07 0.76 ACRES PROPOSED INLET AREA-CB-09 0.97 ACRES PROPOSED INLET AREA-CB-10 1.06 ACRES EXISTING INLET AREA-CB-01 1.77 ACRES 32' OF 18" RCP @ 1.00% 32' OF 18" RCP @ 1.00% 33' OF 18" RCP @ 1.00%216' OF 18" HDPE @ 1.62%PROPOSED INLET AREA-CB-08 0.59 ACRES CB-07 0+00.00 Storm RIM:324.23 INV OUT:319.21 W 32' LF OF 18" RCP @1.0% FL 298.5'BASIS OF BEARING:GRID NORTH, ARKANSASCOORDINATE SYSTEM, NORTH ZONEBY GPS OBSERVATIONFOR USE AND BENEFIT OF: 129 N. Main Street, Benton, Arkansas 72015 PH. (501)315-2626 FAX (501) 315-0024 www.hopeconsulting.com C.A.D. BY:DRAWING NUMBER:DATE: SHEET: REVISED:E:\HOPE CONSULTING\0.OFFICE PROJECTS\ASSIGNED PROJECTS]\25-0107 JACOB POWELL-CASTLE VALLEY ROAD\WORKING\T02\CORRIDOR\FINAL 8\SAJ_MH_ABIR_08.04.2025_-25-0107_JACOB POWELL.DWG CHECKED BY: SCALE: A SUBDIVISION IN PULASKI COUNTY, ARKANSAS CASTLE VALLEY SUBDIVISION. JACOB POWELL 25-0107 500 01S 13W 0 06 340 62 1664 09/08/2025 ## C-3.0 INLET CALCULATION 1' = 60"CERTIFICATE O F AUTHORI Z ATIONNo. 1931 HOPE CONSULTING, INC. ARKAN S A SVICINITY MAP: PROJECT LOCATION HDPE RCP 8W 8" WATER LINE 8S 8" SWERE LINE INLET ANALYSIS PIPE ANALYSIS Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 13.84 cfs Time to peak = 0.12 hrs Hyd. Volume = 5,811 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 4.59 cfs Time to peak = 0.37 hrs Hyd. Volume = 22,916 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 12.00 12.00 14.00 14.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 2-yr frequency Hyd No. 1 Hyd No. 5 Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 16.45 cfs Time to peak = 0.12 hrs Hyd. Volume = 6,908 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 6.74 cfs Time to peak = 0.37 hrs Hyd. Volume = 27,330 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 3.00 3.00 6.00 6.00 9.00 9.00 12.00 12.00 15.00 15.00 18.00 18.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 5-yr frequency Hyd No. 1 Hyd No. 5 Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 18.52 cfs Time to peak = 0.12 hrs Hyd. Volume = 7,777 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 8.99 cfs Time to peak = 0.35 hrs Hyd. Volume = 30,811 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 3.00 3.00 6.00 6.00 9.00 9.00 12.00 12.00 15.00 15.00 18.00 18.00 21.00 21.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 10-yr frequency Hyd No. 1 Hyd No. 5 Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 21.27 cfs Time to peak = 0.12 hrs Hyd. Volume = 8,932 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 13.61 cfs Time to peak = 0.35 hrs Hyd. Volume = 35,348 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 25-yr frequency Hyd No. 1 Hyd No. 5 Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 23.29 cfs Time to peak = 0.12 hrs Hyd. Volume = 9,780 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 17.71 cfs Time to peak = 0.33 hrs Hyd. Volume = 38,668 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 50-yr frequency Hyd No. 1 Hyd No. 5 Multi-Hydrograph Plot Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 25.27 cfs Time to peak = 0.12 hrs Hyd. Volume = 10,614 cuft Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 21.72 cfs Time to peak = 0.33 hrs Hyd. Volume = 41,932 cuft 0.0 0.1 0.2 0.3 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 28.00 28.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A and Reservior 100-yr frequency Hyd No. 1 Hyd No. 5 1 2 3 4 5 1 Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Project: POND 5.gpw Tuesday, 08 / 26 / 2025 Hyd.Origin Description Legend 1 Rational PRE DEVELOPMENT A 2 Rational PRE DEVELOPMENT B 3 Combine Combine 4 Rational POST DEVELOPMENT 5 Reservoir Reservior Hydrograph Return Period Recap 2 Hyd. Hydrograph Inflow Peak Outflow (cfs) Hydrograph No. type hyd(s) Description (origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 Rational ------ ------- 13.84 ------- 16.45 18.52 21.27 23.29 25.27 PRE DEVELOPMENT A 2 Rational ------ ------- 28.22 ------- 33.64 37.91 43.50 47.58 51.60 PRE DEVELOPMENT B 3 Combine 1, 2 ------- 34.15 ------- 40.69 45.85 52.61 57.56 62.43 Combine 4 Rational ------ ------- 31.85 ------- 37.98 42.82 49.12 53.73 58.26 POST DEVELOPMENT 5 Reservoir 4 ------- 4.593 ------- 6.737 8.991 13.61 17.71 21.72 Reservior Proj. file: POND 5.gpw Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Summary Report 3 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 13.84 1 7 5,811 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 28.22 1 11 18,624 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 34.15 1 11 24,435 1, 2 ------ ------ Combine 4 Rational 31.85 1 12 22,934 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 4.593 1 22 22,916 4 300.47 20,028 Reservior POND 5.gpw Return Period: 2 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 13.84 cfs Storm frequency = 2 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 5,811 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 5.391 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 4 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 2.00 2.00 4.00 4.00 6.00 6.00 8.00 8.00 10.00 10.00 12.00 12.00 14.00 14.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 2 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 28.22 cfs Storm frequency = 2 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 18,624 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 4.477 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 5 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 5.00 5.00 10.00 10.00 15.00 15.00 20.00 20.00 25.00 25.00 30.00 30.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 2 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 34.15 cfs Storm frequency = 2 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 24,435 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 6 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 5.00 5.00 10.00 10.00 15.00 15.00 20.00 20.00 25.00 25.00 30.00 30.00 35.00 35.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 2 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 31.85 cfs Storm frequency = 2 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 22,934 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 4.305 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 7 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 5.00 5.00 10.00 10.00 15.00 15.00 20.00 20.00 25.00 25.00 30.00 30.00 35.00 35.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 2 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 4.593 cfs Storm frequency = 2 yrs Time to peak = 0.37 hrs Time interval = 1 min Hyd. volume = 22,916 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 300.47 ft Reservoir name = <New Pond> Max. Storage = 20,028 cuft Storage Indication method used. 8 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 Q (cfs) 0.00 0.00 5.00 5.00 10.00 10.00 15.00 15.00 20.00 20.00 25.00 25.00 30.00 30.00 35.00 35.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 2 Year Hyd No. 5 Hyd No. 4 Total storage used = 20,028 cuft Pond Report 9 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Pond No. 1 - <New Pond> Pond Data Contours -User-defined contour areas. Average end area method used for volume calculation. Begining Elevation = 298.50 ft Stage / Storage Table Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft) 0.00 298.50 9,000 0 0 1.00 299.50 10,176 9,588 9,588 2.00 300.50 11,424 10,800 20,388 3.00 301.50 12,744 12,084 32,472 4.00 302.50 14,136 13,440 45,912 Culvert / Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise (in)Inactive 0.00 0.00 0.00 Span (in)= 18.00 0.00 0.00 0.00 No. Barrels = 1 0 0 0 Invert El. (ft)= 298.50 0.00 0.00 0.00 Length (ft)= 40.00 0.00 0.00 0.00 Slope (%)= 1.00 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff.= 0.60 0.60 0.60 0.60 Multi-Stage = n/a No No No Crest Len (ft)= 0.50 2.50 6.00 0.00 Crest El. (ft)= 298.50 300.50 301.00 0.00 Weir Coeff.= 3.33 3.33 3.33 3.33 Weir Type = Rect Rect Rect --- Multi-Stage = No No No No Exfil.(in/hr)= 0.000 (by Wet area) TW Elev. (ft)= 0.00 Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s). 0.00 7.00 14.00 21.00 28.00 35.00 42.00 49.00 56.00 63.00 70.00 77.00 Stage (ft) 0.00 298.50 1.00 299.50 2.00 300.50 3.00 301.50 4.00 302.50 Elev (ft) Discharge (cfs) Stage / Discharge Total Q Hydrograph Summary Report 10 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 16.45 1 7 6,908 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 33.64 1 11 22,201 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 40.69 1 11 29,108 1, 2 ------ ------ Combine 4 Rational 37.98 1 12 27,348 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 6.737 1 22 27,330 4 300.76 23,482 Reservior POND 5.gpw Return Period: 5 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 16.45 cfs Storm frequency = 5 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 6,908 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 6.409 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 11 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 3.00 3.00 6.00 6.00 9.00 9.00 12.00 12.00 15.00 15.00 18.00 18.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 5 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 33.64 cfs Storm frequency = 5 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 22,201 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 5.337 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 12 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 5.00 5.00 10.00 10.00 15.00 15.00 20.00 20.00 25.00 25.00 30.00 30.00 35.00 35.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 5 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 40.69 cfs Storm frequency = 5 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 29,108 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 13 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 5 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 37.98 cfs Storm frequency = 5 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 27,348 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 5.134 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 14 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 5 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 6.737 cfs Storm frequency = 5 yrs Time to peak = 0.37 hrs Time interval = 1 min Hyd. volume = 27,330 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 300.76 ft Reservoir name = <New Pond> Max. Storage = 23,482 cuft Storage Indication method used. 15 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 5 Year Hyd No. 5 Hyd No. 4 Total storage used = 23,482 cuft Hydrograph Summary Report 16 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 18.52 1 7 7,777 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 37.91 1 11 25,023 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 45.85 1 11 32,800 1, 2 ------ ------ Combine 4 Rational 42.82 1 12 30,829 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 8.991 1 21 30,811 4 300.96 25,905 Reservior POND 5.gpw Return Period: 10 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 18.52 cfs Storm frequency = 10 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 7,777 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 7.216 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 17 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 3.00 3.00 6.00 6.00 9.00 9.00 12.00 12.00 15.00 15.00 18.00 18.00 21.00 21.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 10 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 37.91 cfs Storm frequency = 10 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 25,023 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 6.015 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 18 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 10 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 45.85 cfs Storm frequency = 10 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 32,800 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 19 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 10 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 42.82 cfs Storm frequency = 10 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 30,829 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 5.787 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 20 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 10 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 8.991 cfs Storm frequency = 10 yrs Time to peak = 0.35 hrs Time interval = 1 min Hyd. volume = 30,811 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 300.96 ft Reservoir name = <New Pond> Max. Storage = 25,905 cuft Storage Indication method used. 21 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 10 Year Hyd No. 5 Hyd No. 4 Total storage used = 25,905 cuft Hydrograph Summary Report 22 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 21.27 1 7 8,932 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 43.50 1 11 28,708 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 52.61 1 11 37,640 1, 2 ------ ------ Combine 4 Rational 49.12 1 12 35,367 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 13.61 1 21 35,348 4 301.18 28,642 Reservior POND 5.gpw Return Period: 25 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 21.27 cfs Storm frequency = 25 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 8,932 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 8.287 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 23 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 25 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 43.50 cfs Storm frequency = 25 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 28,708 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 6.901 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 24 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 25 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 52.61 cfs Storm frequency = 25 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 37,640 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 25 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 25 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 49.12 cfs Storm frequency = 25 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 35,367 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 6.639 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 26 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 25 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 13.61 cfs Storm frequency = 25 yrs Time to peak = 0.35 hrs Time interval = 1 min Hyd. volume = 35,348 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 301.18 ft Reservoir name = <New Pond> Max. Storage = 28,642 cuft Storage Indication method used. 27 0.0 0.7 1.3 2.0 2.7 3.3 4.0 4.7 5.3 6.0 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 25 Year Hyd No. 5 Hyd No. 4 Total storage used = 28,642 cuft Hydrograph Summary Report 28 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 23.29 1 7 9,780 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 47.58 1 11 31,405 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 57.56 1 11 41,185 1, 2 ------ ------ Combine 4 Rational 53.73 1 12 38,687 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 17.71 1 20 38,668 4 301.32 30,296 Reservior POND 5.gpw Return Period: 50 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 23.29 cfs Storm frequency = 50 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 9,780 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 9.074 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 29 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 50 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 47.58 cfs Storm frequency = 50 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 31,405 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 7.549 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 30 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 50 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 57.56 cfs Storm frequency = 50 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 41,185 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 31 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 50 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 53.73 cfs Storm frequency = 50 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 38,687 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 7.262 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 32 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 50 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 17.71 cfs Storm frequency = 50 yrs Time to peak = 0.33 hrs Time interval = 1 min Hyd. volume = 38,668 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 301.32 ft Reservoir name = <New Pond> Max. Storage = 30,296 cuft Storage Indication method used. 33 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 50 Year Hyd No. 5 Hyd No. 4 Total storage used = 30,296 cuft Hydrograph Summary Report 34 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 25.27 1 7 10,614 ------ ------ ------ PRE DEVELOPMENT A 2 Rational 51.60 1 11 34,057 ------ ------ ------ PRE DEVELOPMENT B 3 Combine 62.43 1 11 44,671 1, 2 ------ ------ Combine 4 Rational 58.26 1 12 41,951 ------ ------ ------ POST DEVELOPMENT 5 Reservoir 21.72 1 20 41,932 4 301.44 31,704 Reservior POND 5.gpw Return Period: 100 Year Tuesday, 08 / 26 / 2025 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 1 PRE DEVELOPMENT A Hydrograph type = Rational Peak discharge = 25.27 cfs Storm frequency = 100 yrs Time to peak = 0.12 hrs Time interval = 1 min Hyd. volume = 10,614 cuft Drainage area = 5.460 ac Runoff coeff. = 0.47 Intensity = 9.848 in/hr Tc by User = 7.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 35 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 0.2 Q (cfs) 0.00 0.00 4.00 4.00 8.00 8.00 12.00 12.00 16.00 16.00 20.00 20.00 24.00 24.00 28.00 28.00 Q (cfs) Time (hrs) PRE DEVELOPMENT A Hyd. No. 1 -- 100 Year Hyd No. 1 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 2 PRE DEVELOPMENT B Hydrograph type = Rational Peak discharge = 51.60 cfs Storm frequency = 100 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 34,057 cuft Drainage area = 9.550 ac Runoff coeff. = 0.66 Intensity = 8.187 in/hr Tc by User = 11.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 36 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) PRE DEVELOPMENT B Hyd. No. 2 -- 100 Year Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 3 Combine Hydrograph type = Combine Peak discharge = 62.43 cfs Storm frequency = 100 yrs Time to peak = 0.18 hrs Time interval = 1 min Hyd. volume = 44,671 cuft Inflow hyds. = 1, 2 Contrib. drain. area = 15.010 ac 37 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 70.00 70.00 Q (cfs) Time (hrs) Combine Hyd. No. 3 -- 100 Year Hyd No. 3 Hyd No. 1 Hyd No. 2 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 4 POST DEVELOPMENT Hydrograph type = Rational Peak discharge = 58.26 cfs Storm frequency = 100 yrs Time to peak = 0.20 hrs Time interval = 1 min Hyd. volume = 41,951 cuft Drainage area = 15.100 ac Runoff coeff. = 0.49 Intensity = 7.875 in/hr Tc by User = 12.00 min IDF Curve = IDF.IDF Asc/Rec limb fact = 1/1 38 0.0 0.0 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.3 0.4 0.4 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) POST DEVELOPMENT Hyd. No. 4 -- 100 Year Hyd No. 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Hyd. No. 5 Reservior Hydrograph type = Reservoir Peak discharge = 21.72 cfs Storm frequency = 100 yrs Time to peak = 0.33 hrs Time interval = 1 min Hyd. volume = 41,932 cuft Inflow hyd. No. = 4 - POST DEVELOPMENT Max. Elevation = 301.44 ft Reservoir name = <New Pond> Max. Storage = 31,704 cuft Storage Indication method used. 39 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Q (cfs) 0.00 0.00 10.00 10.00 20.00 20.00 30.00 30.00 40.00 40.00 50.00 50.00 60.00 60.00 Q (cfs) Time (hrs) Reservior Hyd. No. 5 -- 100 Year Hyd No. 5 Hyd No. 4 Total storage used = 31,704 cuft Hydraflow Rainfall Report 40 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Return Intensity-Duration-Frequency Equation Coefficients (FHA) Period (Yrs)B D E (N/A) 1 22.9744 4.8000 0.6387 -------- 2 26.8470 5.0000 0.6460 -------- 3 0.0000 0.0000 0.0000 -------- 5 33.8942 5.5000 0.6594 -------- 10 39.0884 5.7000 0.6648 -------- 25 43.0825 5.4000 0.6547 -------- 50 45.2011 5.1000 0.6440 -------- 100 47.7442 4.9000 0.6374 -------- File name: IDF.IDF Intensity = B / (Tc + D)^E Return Intensity Values (in/hr) Period (Yrs) 5 min 10 15 20 25 30 35 40 45 50 55 60 1 5.35 4.11 3.41 2.95 2.63 2.38 2.18 2.03 1.89 1.78 1.68 1.60 2 6.07 4.67 3.88 3.36 2.98 2.70 2.48 2.30 2.14 2.02 1.91 1.81 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 7.19 5.56 4.63 4.01 3.56 3.22 2.95 2.73 2.55 2.40 2.27 2.15 10 8.09 6.27 5.21 4.52 4.01 3.63 3.33 3.08 2.88 2.70 2.55 2.42 25 9.30 7.19 5.98 5.18 4.61 4.17 3.82 3.54 3.31 3.11 2.94 2.79 50 10.19 7.87 6.54 5.67 5.05 4.57 4.19 3.89 3.63 3.42 3.23 3.07 100 11.07 8.53 7.10 6.15 5.47 4.96 4.55 4.22 3.95 3.72 3.52 3.34 Tc = time in minutes. Values may exceed 60. Rainfall Precipitation Table (in) Precip. file name: Sample.pcp Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 0.00 2.20 0.00 3.30 4.25 5.77 6.80 7.95 SCS 6-Hr 0.00 1.80 0.00 0.00 2.60 0.00 0.00 4.00 Huff-1st 0.00 1.55 0.00 2.75 4.00 5.38 6.50 8.00 Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-4th 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Custom 0.00 1.75 0.00 2.80 3.90 5.25 6.00 7.10 Hydraflow Table of Contents POND 5.gpw Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2026 Tuesday, 08 / 26 / 2025 Watershed Model Schematic...................................................................................... 1 Hydrograph Return Period Recap............................................................................. 2 2 - Year Summary Report......................................................................................................................... 3 Hydrograph Reports................................................................................................................... 4 Hydrograph No. 1, Rational, PRE DEVELOPMENT A............................................................. 4 Hydrograph No. 2, Rational, PRE DEVELOPMENT B............................................................. 5 Hydrograph No. 3, Combine, Combine.................................................................................... 6 Hydrograph No. 4, Rational, POST DEVELOPMENT.............................................................. 7 Hydrograph No. 5, Reservoir, Reservior.................................................................................. 8 Pond Report - <New Pond>................................................................................................. 9 5 - Year Summary Report.......................................................................................................................10 Hydrograph Reports.................................................................................................................11 Hydrograph No. 1, Rational, PRE DEVELOPMENT A...........................................................11 Hydrograph No. 2, Rational, PRE DEVELOPMENT B...........................................................12 Hydrograph No. 3, Combine, Combine..................................................................................13 Hydrograph No. 4, Rational, POST DEVELOPMENT............................................................14 Hydrograph No. 5, Reservoir, Reservior................................................................................15 10 - Year Summary Report.......................................................................................................................16 Hydrograph Reports.................................................................................................................17 Hydrograph No. 1, Rational, PRE DEVELOPMENT A...........................................................17 Hydrograph No. 2, Rational, PRE DEVELOPMENT B...........................................................18 Hydrograph No. 3, Combine, Combine..................................................................................19 Hydrograph No. 4, Rational, POST DEVELOPMENT............................................................20 Hydrograph No. 5, Reservoir, Reservior................................................................................21 25 - Year Summary Report.......................................................................................................................22 Hydrograph Reports.................................................................................................................23 Hydrograph No. 1, Rational, PRE DEVELOPMENT A...........................................................23 Hydrograph No. 2, Rational, PRE DEVELOPMENT B...........................................................24 Hydrograph No. 3, Combine, Combine..................................................................................25 Hydrograph No. 4, Rational, POST DEVELOPMENT............................................................26 Hydrograph No. 5, Reservoir, Reservior................................................................................27 50 - Year Summary Report.......................................................................................................................28 Hydrograph Reports.................................................................................................................29 Hydrograph No. 1, Rational, PRE DEVELOPMENT A...........................................................29 Hydrograph No. 2, Rational, PRE DEVELOPMENT B...........................................................30 Hydrograph No. 3, Combine, Combine..................................................................................31 Hydrograph No. 4, Rational, POST DEVELOPMENT............................................................32 Contents continued...POND 5.gpw Hydrograph No. 5, Reservoir, Reservior................................................................................33 100 - Year Summary Report.......................................................................................................................34 Hydrograph Reports.................................................................................................................35 Hydrograph No. 1, Rational, PRE DEVELOPMENT A...........................................................35 Hydrograph No. 2, Rational, PRE DEVELOPMENT B...........................................................36 Hydrograph No. 3, Combine, Combine..................................................................................37 Hydrograph No. 4, Rational, POST DEVELOPMENT............................................................38 Hydrograph No. 5, Reservoir, Reservior................................................................................39 IDF Report..................................................................................................................40 NOAA Atlas 14, Volume 9, Version 2 Location name: Mabelvale, Arkansas, USA* Latitude: 34.6229°, Longitude: -92.3945° Elevation: 352 ft** * source: ESRI Maps ** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Deborah Martin, Sandra Pavlovic, Ishani Roy, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Michael Yekta, Geoffery Bonnin NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 5.36 (4.39‑6.55) 6.08 (4.97‑7.43) 7.21 (5.87‑8.82) 8.12 (6.58‑9.97) 9.32 (7.27‑11.7) 10.2 (7.80‑13.0) 11.1 (8.18‑14.4) 11.9 (8.45‑15.9) 13.0 (8.87‑17.8) 13.8 (9.18‑19.2) 10-min 3.93 (3.22‑4.79) 4.45 (3.64‑5.44) 5.28 (4.30‑6.46) 5.95 (4.81‑7.30) 6.83 (5.32‑8.56) 7.48 (5.71‑9.52) 8.11 (5.99‑10.6) 8.74 (6.19‑11.6) 9.52 (6.49‑13.0) 10.1 (6.72‑14.1) 15-min 3.20 (2.61‑3.90) 3.62 (2.96‑4.42) 4.29 (3.49‑5.25) 4.83 (3.91‑5.94) 5.55 (4.33‑6.96) 6.08 (4.64‑7.74) 6.60 (4.87‑8.58) 7.10 (5.03‑9.47) 7.74 (5.28‑10.6) 8.20 (5.46‑11.4) 30-min 2.38 (1.95‑2.91) 2.71 (2.21‑3.31) 3.22 (2.62‑3.95) 3.64 (2.94‑4.47) 4.18 (3.26‑5.24) 4.58 (3.50‑5.83) 4.97 (3.67‑6.46) 5.34 (3.78‑7.12) 5.81 (3.96‑7.95) 6.15 (4.10‑8.58) 60-min 1.60 (1.31‑1.95) 1.81 (1.48‑2.21) 2.15 (1.75‑2.63) 2.43 (1.97‑2.98) 2.80 (2.18‑3.52) 3.08 (2.35‑3.92) 3.35 (2.47‑4.36) 3.62 (2.56‑4.82) 3.96 (2.70‑5.42) 4.21 (2.81‑5.87) 2-hr 1.00 (0.825‑1.21) 1.13 (0.933‑1.37) 1.35 (1.10‑1.64) 1.52 (1.24‑1.85) 1.75 (1.38‑2.19) 1.93 (1.49‑2.44) 2.10 (1.57‑2.72) 2.28 (1.63‑3.02) 2.50 (1.72‑3.41) 2.67 (1.79‑3.70) 3-hr 0.752 (0.622‑0.907) 0.850 (0.702‑1.02) 1.01 (0.832‑1.22) 1.14 (0.936‑1.39) 1.33 (1.05‑1.65) 1.47 (1.14‑1.85) 1.61 (1.20‑2.08) 1.75 (1.26‑2.32) 1.94 (1.34‑2.64) 2.09 (1.40‑2.88) 6-hr 0.452 (0.377‑0.541) 0.514 (0.428‑0.615) 0.617 (0.512‑0.741) 0.705 (0.582‑0.850) 0.830 (0.664‑1.03) 0.930 (0.726‑1.17) 1.03 (0.778‑1.33) 1.14 (0.823‑1.50) 1.28 (0.892‑1.73) 1.39 (0.944‑1.91) 12-hr 0.264 (0.222‑0.314) 0.304 (0.255‑0.361) 0.371 (0.310‑0.442) 0.430 (0.357‑0.514) 0.515 (0.416‑0.638) 0.584 (0.460‑0.732) 0.656 (0.499‑0.841) 0.732 (0.534‑0.961) 0.836 (0.587‑1.13) 0.919 (0.627‑1.25) 24-hr 0.155 (0.131‑0.182) 0.179 (0.151‑0.211) 0.221 (0.186‑0.261) 0.258 (0.216‑0.306) 0.312 (0.254‑0.385) 0.357 (0.283‑0.445) 0.403 (0.309‑0.514) 0.453 (0.333‑0.592) 0.522 (0.369‑0.700) 0.577 (0.396‑0.781) 2-day 0.090 (0.077‑0.105) 0.104 (0.088‑0.122) 0.128 (0.108‑0.150) 0.149 (0.126‑0.175) 0.180 (0.148‑0.220) 0.206 (0.164‑0.254) 0.232 (0.179‑0.294) 0.261 (0.193‑0.339) 0.301 (0.214‑0.401) 0.333 (0.230‑0.448) 3-day 0.066 (0.056‑0.077) 0.076 (0.065‑0.088) 0.092 (0.079‑0.108) 0.107 (0.091‑0.126) 0.129 (0.106‑0.157) 0.147 (0.118‑0.180) 0.165 (0.128‑0.208) 0.185 (0.137‑0.239) 0.212 (0.151‑0.281) 0.233 (0.162‑0.313) 4-day 0.053 (0.045‑0.061) 0.060 (0.052‑0.070) 0.074 (0.063‑0.086) 0.085 (0.072‑0.099) 0.102 (0.084‑0.123) 0.115 (0.093‑0.141) 0.129 (0.100‑0.162) 0.144 (0.107‑0.185) 0.165 (0.118‑0.217) 0.181 (0.126‑0.241) 7-day 0.035 (0.030‑0.040) 0.040 (0.034‑0.046) 0.048 (0.041‑0.055) 0.055 (0.047‑0.064) 0.065 (0.054‑0.078) 0.073 (0.059‑0.089) 0.081 (0.063‑0.101) 0.090 (0.067‑0.115) 0.101 (0.073‑0.133) 0.110 (0.077‑0.147) 10-day 0.027 (0.024‑0.031) 0.031 (0.027‑0.036) 0.037 (0.032‑0.043) 0.042 (0.036‑0.049) 0.049 (0.041‑0.059) 0.055 (0.044‑0.066) 0.060 (0.047‑0.075) 0.066 (0.050‑0.085) 0.075 (0.054‑0.097) 0.081 (0.057‑0.107) 20-day 0.018 (0.016‑0.021) 0.020 (0.018‑0.023) 0.023 (0.020‑0.027) 0.026 (0.023‑0.030) 0.030 (0.025‑0.035) 0.033 (0.027‑0.039) 0.035 (0.028‑0.043) 0.038 (0.029‑0.048) 0.042 (0.030‑0.054) 0.045 (0.032‑0.059) 30-day 0.015 (0.013‑0.017) 0.016 (0.014‑0.019) 0.019 (0.016‑0.021) 0.021 (0.018‑0.024) 0.023 (0.019‑0.027) 0.025 (0.021‑0.030) 0.027 (0.022‑0.033) 0.029 (0.022‑0.037) 0.032 (0.023‑0.041) 0.034 (0.024‑0.044) 45-day 0.012 (0.010‑0.013) 0.013 (0.012‑0.015) 0.015 (0.013‑0.017) 0.017 (0.015‑0.019) 0.019 (0.016‑0.022) 0.021 (0.017‑0.024) 0.022 (0.018‑0.027) 0.024 (0.018‑0.030) 0.026 (0.019‑0.033) 0.027 (0.019‑0.035) 60-day 0.010 (0.009‑0.011) 0.011 (0.010‑0.013) 0.013 (0.012‑0.015) 0.015 (0.013‑0.017) 0.017 (0.014‑0.019) 0.018 (0.015‑0.022) 0.020 (0.016‑0.024) 0.021 (0.016‑0.026) 0.023 (0.016‑0.029) 0.024 (0.017‑0.031) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical 6/13/25, 12:13 PM Precipitation Frequency Data Server https://hdsc.nws.noaa.gov/pfds/pfds_printpage.html?lat=34.6229&lon=-92.3945&data=intensity&units=english&series=pds 1/3