Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
03 - Design Report - Walton Homestead - Drainage
----------------- DRAINAGE REPORT Walton Homestead Subdivision BOZEMAN, MONTANA July 2,2003 Prepared By: Rocky Mountain Engineers 1700 W. Koch Street, Suite 7 Bozeman,Montana, 59715 (406) 586-4859 Table of Contents INTRODUCTION ON-SITE RUNOFF AND DRAINAGE BASIN CALCULATIONS OFF-SITE STORM DRAINAGE SUPPLEMENTAL INFORMATION Drainage Basin Summary Drainage Basin Composite "C" Calculations Drainage Basin Detention Volume Calculations Time of Concentration Graph Intensity-Duration-Frequency Graphs Storm Drain Pipe Sizing Calculation Sheets Off-Site Basin Maps Off-Site Runoff Calculations Storm Water Maintenance Plan INTRODUCTION Walton Homestead Subdivision is a residential and commercial development on Tracts 1,2, 3, and 4 of Certificate of Survey No. 2085 and the Matheson parcel described in Book 144,Page 373 of Gallatin County records. The development is located in Bozeman, Montana on approximately thirty-five acres located north of Durston Road, south of Oak Street, west of the Gallatin County Rest Home, and east of the Covered Wagon Mobile Home Park. The site slopes downward to the north at a 1.3% grade. The property drains to the mouth of a drainage culvert under Oak Street about 95 feet west of the development's northwest corner. This report describes the storm drainage detention facilities planned for the development. The Rational Method was used in this report to determine the storm runoff quantities. This is the most widely used method of determining runoff from small drainage areas such as these. The Rational Formula is: Q =C I A, where Q is the calculated storm runoff, C is the coefficient of runoff for the basin, I is the rainfall intensity, and A is the basin area. Antecedent precipitation for the less frequent, higher intensity storms is accounted for by multiplying by a"frequency factor" (Cf). This factor is equal to 1.10 for the 25-year storm and 1.25 for the 100-year storm. The modified formula for the higher intensity storms is: Q = CfCIA ON-SITE RUNOFF AND DRAINAGE BASIN CALCULATIONS The runoff from the 10-year storm for each drainage basin within Walton Homestead Subdivision will be directed and detained in an underground structure or a grassed pond. The underground structures or detention ponds, and the grassed swale leading to them, will reduce the amount of settlable solids, silt, oils, grease, and other pollutants in the storm water runoff. Each detention area has an outlet structure consisting of a concrete pipe set vertically in the ground at the low point of the basin. The pipe extends out of the ground, and the top is covered with a concrete lid or metal grating. A vertical slot of sufficient width is cast in the pipe to allow calculated historic runoff to flow from the structure into a discharge pipe leading to a storm sewer or drainage ditch below the detention area. The acreage of each drainage basin was computed, and the historic runoff determined. A value of 0.20 was used for the Coefficient of Runoff(C) for historic conditions. A mass balance computation was then made to determine the required volume of storage. A Coefficient of Runoff for developed conditions was calculated based on the amount of pervious and impervious area within each basin. The following tables provide a summary of the areas, historic runoff, detention area storage volume, outlet structure slot width, etc. The other pages that follow show the mass balance computations for each drainage basin. Copies of Figures I-1, I-2 and I-3, and other references are included at the end of this report. U MMp _1 O 0O C. rn 4 N "7 (D S 2 v x• CO�� �g N r z � to f/7 v L!J in r to p` �•Q� i 0 Q. G N � ® w O r tm o z ® � a p > ""Em '�- \ ° r� C d o N N M ISM A- N 00 A uumawiwi- O .� OFF-SITE STORM DRAINAGE Walton Homestead Subdivision is a 35 acre parcel located north of Durston Road, south of Oak Street, west of the Gallatin County Rest Home, and east of the Covered Wagon Mobile Home Park. An irrigation ditch, which also carries storm runoff, enters the south end of the property at Durston Road, approximately 175 feet west of the southeast property corner. The ditch flows north and west through the property, exiting the west property line about 475 feet south of the northwest corner of the property. The ditch then flows north on the west side of the property line to Oak Street where the ditch turns west and flows about 95 feet to an existing 30 inch culvert under Oak Street. The drainage basin of this ditch is shown on the aerial photo contour maps that are a part of the City of Bozeman Stormwater Master Plan (1982). The basin above the subdivision is approximately 344 acres in size. It is a long and narrow basin which begins approximately `/2 mile south of Stucky Road on the east side of South 19`h Avenue. The basin extends northward through Bozeman, and is little more than 11/4 mile wide at its widest point near Bozeman High School. The attached calculations indicate the estimated storm runoff from the basin, and the storm drain pipe size through the Walton Homestead Subdivision. The runoff values were estimated using the Natural Resource Conservation Service TR-55 Chart Method. The 25-year flow was estimated to be 69 cubic feet per second (cfs), and the 100-year flow was estimated to be 98 cfs. The 24-hour, precipitation values were obtained from U.S. Weather Bureau isopluvial maps. The runoff curve number was determined assuming that 50% of the land within the basin would ultimately be developed in city lot and commercial type development. A copy of the computation sheets are included with this report. The capacity of a 36 inch diameter reinforced concrete pipe was estimated using Flow Master, a Haestad Methods computer program. The calculated capacity was determined to be 64 cfs. This value is within 7% of the estimated 25-year runoff from the basin, and was determined to be acceptable because of the assumptions involved in determining the offsite runoff and the fact that no detention within the basin above the subdivision was accounted for in the runoff estimate. The 36 inch storm drain pipe proposed to carry the storm runoff through the subdivision discharges to-an open ditch approximately 700 feet south of Oak Street. The open ditch will be constructed to the northwest corner of the subdivision where it will meet the existing ditch from the south and the roadside ditch along the south side of Oak Street. SUPPLEMENTAL INFORMATION Co N C r 00 00 -0 00 CO CO 00 M N N CO 00 00 CO 00 00 O O U = M (h M M M Cl) M M .\- r r c7 r r M f� r rn ' < 0 0 0 U) O O O 00 O O O O (D O O a M d 1 - Lq - - P Lq P Ln to If) O o o cD u) Uf x 4 i r r r r r r O r v a M a A = n 0 0 0 0 0 0 00 0 00 u f r OoOc? o ryr U� 0l� 0 x + O r r O r r r r O O r A t M M O O V' (O V' M M N O O M O V' E V O V O N N (D V' V' O M (O O (D O (D O M r M U) (5 00 m M 00 "T r (D O r N M U) r h- O i r r M 00 N (D O U) U) U) V' M V' m M U) 0 U) (D 0 U) O CO m w (D N O U O U) w M (O O N M M r r 00 M 6) V' M N vA V' V' (O O (D (D O N O U) V' O N V' I� O r CO M r - O r r O N r Ox r O N — N O r r CDr O O O O O O O O O O O O O O O O O O O O O O O O O O O O i (0 N (D N M N M ti M U) O U) N CO U) h- N N O N V' O O N h- .� 00 O do r- r (() N o M V' O O O U) O O) O O Q. O N O M O r U) M O O r �- O r r r r r r O O O r O r O r r r r c- O O O� .y i C (() M O V' M Imo- N 1'- M N M O O V' O V' -,Zr (D O U) N M N 00 M co V' O M N V' U7 (n V' V' V' I`- O7 r N (D N Ih- r M V' M N U) U) co co y v N t!) r N U) O O M O 00 O O O r O 0 0 o — 0 0 0 0 0 0 G M O h O_ O V' U U)) 0 M M i- U) M M CO O M O W M U) U)0 M U) N A I'- N M V N O O O_ M 0 M N I� V to 0 V' M M to M V' I� M C w N V' O O) CO 0) N U) N M U) (D O I- cl) V' O I-- t-- O U) V' I- N N CO M N r CO U) M W I- M O M (D (D t-- 0) N h- (D Imo- I� r N to M Co o N (D 00 N r r (C) (D r r r M V' (n N Cl) (n r U) r N N r M ? r CN U � i Q ~ i 00 N O M O (D o N CO O N M U) m M N 00 m O O O) (D (D CO h t M IT N N (n N r N N r r M M M r N M N M r N N N r M N r M 0 N c Y� o c c U o m 1 '0 c e- N M tt' L Q (o h Go Cb O N M ('Q,) V' Q (f7 Co cO Q a) Q O N Cl) O t+ e- c- t+ e N N N N N p� S ' C , =3 C i (/) S C� N S (n p (n U) U) U) S Z U) S (n (n :3 U) S (n (n Z) II it Z U) :D cn (0 14- 0) "';r (D CN 0) "t rl- CN 0 (0 (D 0 (N LO CN C) 0 CT) I- (') CN Lf) (D il- t- q" r— r oo r OD "T 0) c4- r (14 r 0 1,- 0 r- CY) r- t- 00 CO (D CA 00 1- CA 0 LO 14- LO LO It It (D (10 U) LO It 'IT tl- (D (0 LO (0 U) (D (D LO (D U) (D It LO (0 (0 (D ri Q C) C) 0 C) C) C) C) 0 C) C) C) (D (D C) 0 C) C) 0 0 C) C) C) 0 C) C) C) 0 o') (o r- C) 0) "t Lo (o (D m Lo r- Lo (y) , co 00 0) 0) C) co co Lo CD co to cj Lo f- N CA r 44- N C) CF) 0 (Y) r (D (Y) N r- IT a) C) dr r lqr (y) (y) LO 0) q* [-- (y) tt N IT 0 0) Cl) 0) NLO — NCO LO (D 0 fl- M ',I- C) I-- r- CD LC) zT r-- N04 (D — 00 C14 r 00 LO 0) OD r- 00 C) cy) QO (0 r- CD C\J tl- (D t- t- r 04 U) CY')'OD C> U') (0 OD cl) r r to (o r r r M d LO CN CY) LO r U') r N N r M C14 N 0 0 C) 0 0 C) C) 0 0 C) 0 C) C) C) 0 C) C) C) 0 0 C) C) 0 C) 0 C) 0 0 0 0 C) 0 C) C) C) 0 0 C) C) 0 C) C) C) 0 0 C) 0 0 C) C) 0 C) C) (D C) 0 "T V' N CD M C) M r r M U) r M t- CO a) (o cy) a) 00 (D C) C) 00 0) "T cy) Co C) (O 0) f-- M r r r r- LO CM CC) r (r) r- Cl N CN C) q q. C) 0 00 — r- U) ',T t (0 — M (0 [1- CY) r LO — C) M M "q (N — C) N N r T M 0 "T .;t r- CN Gry (0 CD Cl) CN — CO (D (D LO C14 C14 LO C\J CY) M CO C14 CO C) cl) r 00 (0 (C) C) r- LO cl) (D N CO LO (D (D CY) r r r r r r r 04 zz � C) (D CD CD C) C) C) C) (D (D C> 0 a C) C) 0 0 0 a 0 C) CD CD CD C> C) C) C) 4 C) C) C) 0 CD C) C) CD 0 C) 0 C) CD CD CD 0 C) O C) 0 C) C) CD C) O C) (D C) 0) 0') 0') CY) 0) CY) 0) m 0) 0) a) CY) (3) 0) a) CY) 0) 0) m CF) 0) 0) 0) m 0) (3) 0) 0) 0 0 C> 0 0 0 0 0 C) 0 0 C) 6 0 0 0 0 0 0 0 0 ci 0 0 0 0 (D 0 6n 00 N (Y) 00 CY) (0 LO 00 LO C14 N CN IT C) "It C) CY) CO C) — C) N CIJ 0 C) (D 00 N Z: r- C\J Cl) r r- CO CY) r 0) (D (D CM LO — C) r- 00 00 C\J C) C, CF) CO LO r C14 0') 00 00 C) 'T r-- 0-) N 'T (0 0) (D (D LO t-- CY) CD 00 (D 04 N 00 M Cj C14 'q- C) M 0') LO CO 1,- (0 C) OD r CO CO U-) LO CY) � CY) C\l r- LO (D Cj cy) LO a) CD 'T N 00 r- ,;t CO CY) (14 CY) r— r OD CO It (D 'IT C) LO C%4 C\l(D C14 tt (D I- (o M CA cli N 'T CD N U') C4 00 (Y) 0 w C) 0 Cl (D w m m r rl- 00 b4 LO CN (Y) r Iq W r- CD LO LO W 14- 0 C14 N r- LO 0 CY) N 00 00 00 Cy) IT 144- CN "q* 00 0) d IT tj LO 00 a) fl- 0) M It LO LJO LO IT r- LO 00 LO C14 C14 (N r- N 1,- 0) C14 Co C) C) cli C14 rl- 0') LO U*) rl- IT LO '4- (D CIJ (D CO — G) (D r — C14 0 CD rl- d LO (C) 00 CY) r r CY) C) r ';T N N CY) tp C\j r- N C) CO C14 N '14' rl- OD rl- C) T- '44- IT Lo M Lo rl- (C) 0 cv) CM (C) — C) CY) Nr OD LO IT LO il- N m — M CD (D 00 rT CD (D Lo Lo co F- (::) a) (o co (c) LO CA C4 C14 N 00 00 0) 14) 141 N LO CY) C14 C) (D cr) C) Lo r 0 0) 0 (C) OD ce) r-- U') r cq N L() r r r r ce) r C14 'T C14 (l) 14t to Q co ti co 0) N Mto to N 00 Q 0) Q c, V LO N 04 C'M 04 Walto lomestead Subdivision - Basin 1 10-Jun-03 2.348 = BASIN AREA (A) 0.446 = COEFFICIENT OF RUNOFF (C) 0.402 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cuft) (tuft.) (cuft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 3.367 1010 121 889 10 2.05 2.146 1287 241 1046 15 1.58 1.649 1484 362 1122 20 1.31 1.367 1641 483 1158 25 1.13 1.183 1774 603 1171 30 1.00 1.051 1891 724 1167 35 0.91 0.950 1996 845 1151 40 0.83 0.871 2091 965 1126 45 0.77 0.807 2179 1086 1093 50 0.72 0.754 2261 1207 1055 55 0.68 0.708 2338 1327 1011 60 0.64 0.670 2410 1448 962 Basin 2 10-Jun-03 5.887 = BASIN AREA (A) 0.571 = COEFFICIENT OF RUNOFF (C) 0.950 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cuff) (alit.) (tuft.) ------ --------------- --------------- --------------- --------------- --------------- 5 3.22 10.824 3247 285 2962 10 2.05 6.898 4139 570 3569 15 1.58 5.300 4770 855 3915 20 1.31 4.396 5275 1140 4135 25 1.13 3.802 5704 1425 4279 30 1.00 3.378 6080 1710 4369 35 0.91 3.056 6417 1995 4421 40 0.83 2.802 6724 2280 4443 45 0.77 2.595 7007 2565 4441 50 0.72 2.423 7270 2850 4419 55 0.68 2.278 7516 3136 4381 60 0.64 2.152 7749 3421 4328 Walto Tomestead Subdivision - Basin 3 10-Jun-03 1.403 = BASIN AREA (A) 0.514 = COEFFICIENT OF RUNOFF (C) 0.287 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (ruin) (in/hr) (cfs) (cu Jt) (cu ft.) (cu fz) --------------- --------------- --------------- --------------- --------------- -------------- 5 3.22 2.322 697 86 611 10 2.05 1.480 888 172 716 15 1.58 1.137 1023 258 765 20 1.31 0.943 1131 344 787 25 1.13 0.816 1223 430 793 30 1.00 0.724 1304 516 788 35 0.91 0.655 1376 602 774 40 0.83 0.601 1442 688 754 45 0.77 0.557 1503 774 729 50 0.72 0.520 1559 860 699 55 0.68 0.489 1612 946 666 60 0.64 0.462 1662 1032 630 Basin 4 10-Jun-03 2.041 = BASIN AREA (A) 0.489 = COEFFICIENT OF RUNOFF (C) 0.433 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft.) (cu ft.) (cu ft) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 3.213 964 130 834 10 2.05 2.048 1229 260 969 15 1.58 1.573 1416 390 1026 20 1.31 1.305 1566 520 1046 25 1.13 1.129 1693 650 1043 30 1.00 1.003 1805 780 1025 35 0.91 0.907 1905 910 995 40 0.83 0.832 1996 1040 956 45 0.77 0.770 2080 1170 910 50 0.72 0.719 2158 1300 858 55 0.68 0.676 2231 1430 801 60 0.64 0.639 2300 1559 741 Waltc lomestead Subdivision - Basin 5 17-Jun-03 5.334 = BASIN AREA (A) 0.414 = COEFFICIENT OF RUNOFF(C) 0.768 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft.) (cu ft.) (cuff.) -------------- -------------- --------------- --------------- --------------- --------------- 5 3.22 7.104 2131 230 1901 10 2.05 4.528 2717 461 2256 15 1.58 3.479 3131 691 2440 20 1.31 2.885 3462 921 2541 25 1.13 2.496 3744 1151 2592 30 1.00 2.217 3990 1382 2609 35 0.91 2.005 4212 1612 2600 40 0.83 1.839 4413 1842 2571 45 0.77 1.703 4599 2072 2526 50 0.72 1.590 4771 2303 2469 55 0.68 1.495 4933 2533 2401 60 0.64 1.413 5086 2763 2323 Basin 6 9-Jun-03 0.418 = BASIN AREA (A) 0.642 = COEFFICIENT OF RUNOFF(C) 0.126 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (inAr) (cfs) (cuff) (tuft.) (cu ft.) --------------- --------------- --------------- --------------- ------------- --------------- 5 3.22 0.864 259 38 221 10 2.05 0.550 330 76 255 15 1.58 0.423 381 113 267 20 1.31 0.351 421 151 270 25 1.13 0.303 455 189 266 30 1.00 0.269 485 227 258 35 0.91 0.244 512 265 247 40 0.83 0.223 536 303 234 45 0.77 0.207 559 340 218 50 0.72 0.193 580 378 202 55 0.68 0.182 600 416 183 60 0.64 0.172 618 454 164 Basin 5A 17-Jun-03 0.274 = BASIN AREA (A) 0.686 = COEFFICIENT OF RUNOFF (C) 0.062 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (ruin) 01",r) (efs) (cu.ft.) (tuft.) (cuft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.605 181 18 163 10 2.05 0.385 231 37 194 15 1.58 0.296 266 55 211 20 1.31 0.246 295 74 221 25 1.13 0.212 319 92 226 30 1.00 0.189 340 ill 229 35 0.91 0.171 358 129 229 40 0.83 0.157 376 148 228 45 0.77 0.145 391 166 225 50 0.72 0.135 406 185 221 55 0.68 0.127 420 203 217 60 0.64 0.120 433 222 211 Walto romestead Subdivision - Basin 7 17-Jun-03 3.572 = BASIN AREA (A) 0.599 = COEFFICIENT OF RUNOFF(C) 0.868 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in✓hr) (cfs) (cu.}t.) (cuff.) (tuft) ------- ------ --------------- --------------- --------------- --------------- -------------- 5 3.22 6.883 2065 261 1804 10 2.05 4.386 2632 521 2111 15 1.58 3.370 3033 782 2251 20 1.31 2.795 3354 1042 2312 25 1.13 2.418 3627 1303 2324 30 1.00 2.148 3866 1563 2303 35 0.91 1.943 4080 1824 2256 40 0.83 1.781 4275 2084 2191 45 0.77 1.650 4455 2345 2110 50 0.72 1.541 4622 2605 2017 55 0.68 1.448 4779 2866 1914 60 0.64 1.369 4927 3126 1801 Basin 8 9-Jun-03 1.586 = BASIN AREA (A) 0.544 = COEFFICIENT OF RUNOFF (C) 0.335 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/kr) (cfs) (tuft) (tuft.) (tuft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 2.779 834 101 733 10 2.05 _ 1.771 1063 201 861 15 1.58 1.361 1225 302 923 20 1.31 1.129 1355 403 952 25 1.13 0.976 1465 503 961 30 1.00 0.867 1561 604 957 35 0.91 0.785 1648 705 943 40 0.83 0.719 1726 805 921 45 0.77 0.666 1799 906 893 50 0.72 0.622 1867 1006 860 55 0.68 0.585 1930 1107 823 60 0.64 0.553 1990 1208 782 Walta Iomestead Subdivision - Basin 9 9-Jun-03 0.419 = BASIN AREA (A) 0.417 =COEFFICIENT OF RUNOFF(C) 0.115 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) 0101r) (cfs) (cu ft.) (cuff.) (cu ft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.562 169 34 134 10 2.05 0.358 215 69 146 15 1.58 0.275 248 103 145 20 1.31 0.228 274 138 137 25 1.13 0.198 296 172 124 30 1.00 0.175 316 206 110 35 0.91 0.159 333 241 93 40 0.83 0.146 349 275 74 45 0.77 0.135 364 309 55 50 0.72 0.126 378 344 34 55 0.68 0.118 390 378 12 60 0.64 0.112 403 413 -10 Basin 10 9-Jun-03 0.409 = BASIN AREA (A) 0.422 = COEFFICIENT OF RUNOFF(C) 0.115 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft.) (cuft.) (tuft) ------ --------------- --------------- --------------- --------------- --------------- 5 3.22 0.556 167 34 132 10 2.05 0.354 213 69 144 15 1.58 0.272 245 103 142 20 1.31 0.226 271 138 133 25 1.13 0.195 293 172 121 30 1.00 0.174 312 207 105 35 0.91 0.157 330 241 88 40 0.83 0.144 345 276 70 45 0.77 0.133 360 310 50 50 0.72 0.124 373 345 29 55 0.68 0.117 386 379 7 60 0.64 0.111 398 414 -16 Walt Homestead Subdivision - Basin 11 9-Jun-03 0.426 = BASIN AREA (A) 0.710 = COEFFICIENT OF RUNOFF (C) 0.084 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu fr.) (cu ft.) (cu ft.) --------------- --------------- -------------- --------------- --------------- --------------- 5 3.22 0.974 292 25 267 10 2.05 0.621 373 51 322 15 1.58 0.477 429 76 353 20 1.31 0.396 475 101 374 25 1.13 0.342 513 127 387 30 1.00 0.304 547 152 395 35 0.91 0.275 578 177 400 40 0.83 0.252 605 202 403 45 0.77 0.234 631 228 403 50 0.72 0.218 654 253 401 55 0.68 0.205 677 278 398 60 0.64 0.194 697 304 394 Basin 12 9-Jun-03 0.703 = BASIN AREA (A) 0.606 = COEFFICIENT OF RUNOFF (C) 0.133 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft) (cu ft.) (cu ft.) --------------- --------------- --------------- -------------- --------------- --------------- 5 3.22 1.371 411 40 371 10 2.05 0.874 524 80 444 15 1.58 0.671 604 120 484 20 1.31 0.557 668 160 508 25 1.13 0.482 722 200 522 30 1.00 0.428 770 240 530 35 0.91 0.387 813 280 533 40 0.83 0.355 852 320 532 45 0.77 0.329 887 360 528 50 0.72 0.307 921 400 521 55 0.68 0.288 952 440 512 60 0.64 0.273 981 480 502 Walt Flomestead Subdivision - Basin 13 9-Jun-03 0.990 = BASIN AREA (A) 0.676 = COEFFICIENT OF RUNOFF(C) 0.194 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu.ft) (cu.Jt.) (cuff) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 2.153 646 58 588 10 2.05 1.372 823 116 707 15 1.58 1.054 949 174 774 20 1.31 0.874 1049 232 817 25 1.13 0.756 1135 291 844 30 1.00 0.672 1209 349 861 35 0.91 0.608 1276 407 870 40 0.83 0.557 1337 465 872 45 0.77 0.516 1394 523 871 50 0.72 0.482 1446 581 865 55 0.68 0.453 1495 639 856 60 0.64 0.428 1541 697 844 Basin 14 27-Jun-03 1.289 = BASIN AREA (A) 0.672 = COEFFICIENT OF RUNOFF (C) 0.263 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft.) (cuJt) (twit.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 2.788 837 79 757 10 2.05 1.777 1066 158 908 15 1.58 1.365 1229 237 992 20 1.31 1.132 1359 316 1043 25 1.13 0.980 1469 395 1074 30 1.00 0.870 1566 474 1092 35 0.91 0.787 1653 553 1100 40 0.83 0.722 1732 632 1100 45 0.77 0.668 1805 711 1094 50 0.72 0.624 1873 790 1083 55 0.68 0.587 1936 869 1067 60 0.64 0.554 1996 948 1048 Walton Homestead Subdivision - Basin 13A 27-Jun-03 0.139 = BASIN AREA (A) 0.500 = COEFFICIENT OF RUNOFF (C) 0.043 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (tuft) (cu ft.) (cn,ft.) --------------- --------------- --------------- -------------- --------------- --------------- 5 3.22 0.224 67 13 54 10 2.05 0.143 86 26 60 15 1.58 0.110 99 39 60 20 1.31 0.091 109 52 57 25 1.13 0.079 118 65 53 30 1.00 0.070 126 78 48 35 0.91 0.063 133 91 42 40 0.83 0.058 139 104 35 45 0.77 0.054 145 117 28 50 0.72 0.050 151 130 21 55 0.68 0.047 156 143 13 60 0.64 0.045 161 156 5 Walton Homestead Subdivision - Basin 14A 27-Jun-03 0.638 = BASIN AREA (A) 0.595 =COEFFICIENT OF RUNOFF (C) 0.125 =HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (tuft.) (cuff) (cuff) 5 3.22 1.222 367 37 329 10 2.05 0.779 467 75 393 15 1.58 0.598 539 112 426 20 1.31 0.496 596 150 446 25 1.13 0.429 644 187 457 30 1.00 0.381 686 224 462 35 0.91 0.345 725 262 463 40 0.83 0.316 759 299 460 45 0.77 0.293 791 337 454 50 0.72 0.274 821 374 447 55 0.68 0.257 849 411 437 60 0.64 0.243 875 449 426 F 'on Homestead Subdivision - Basin 15 9-Jun-03 0.214 = BASIN AREA (A) 0.672 = COEFFICIENT OF RUNOFF (C) 0.045 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (tuft.) (tuft.) (cuff.) --------------- -------------- -------------- --------------- --------------- --------------- 5 3.22 0.463 139 13 125 10 2.05 0.295 177 27 150 15 1.58 0.226 204 40 164 20 1.31 0.188 225 54 172 25 1.13 0.162 244 67 177 30 1.00 0.144 260 81 179 35 0.91 0.131 274 94 180 40 0.83 0.120 287 107 180 45 0.77 0.111 299 121 179 50 0.72 0.104 311 134 176 55 0.68 0.097 321 148 174 60 0.64 0.092 331 161 170 Basin 96 9-Jun-03 0.745 = BASIN AREA (A) 0.679 = COEFFICIENT OF RUNOFF (C) 0.145 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) 0"r) (cfs) (cuft.) (tuft.) (cu;Jt.) ------ --------------- --------------- --------------- --------------- --------------- 5 3.22 1.629 489 43 445 10 2.05 1.038 623 87 536 15 1.58 0.797 718 130 587 20 1.31 0.661 794 174 620 25 1.13 0.572 858 217 641 30 1.00 0.508 915 261 654 35 0.91 0.460 965 304 661 40 0.83 0.422 1012 348 664 45 0.77 0.390 1054 391 663 50 0.72 0.365 1094 435 659 55 0.68 0.343 1131 478 653 60 0.64 0.324 1166 521 645 Walto: Tomestead Subdivision - Basin 17 9-Jun-03 0.161 = BASIN AREA (A) 0.580 =COEFFICIENT OF RUNOFF(C) 0.046 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft.) (cu,ft) (cu ft.) --------------- --------------- -------------- --------------- -------------- --------------- 5 3.22 0.300 90 14 76 10 2.05 0.191 115 27 87 15 1.58 0.147 132 41 91 20 1.31 0.122 146 55 91 25 1.13 0.105 158 69 90 30 1.00 0.094 169 82 86 35 0.91 0.085 178 96 82 40 0.83 0.078 186 110 77 45 0.77 0.072 194 124 71 50 0.72 0.067 202 137 64 55 0.68 0.063 208 151 57 60 0.64 0.060 215 165 50 Basin 18 9-Jun-03 1.303 = BASIN AREA (A) 0.639 =COEFFICIENT OF RUNOFF(C) 0.266 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) 0,11hr) (efs) (cu ff) (cu ff) (cu.fl.) --------------- --------------- --------------- -------------- --------------- --------------- 5 3.22 2.680 804 80 724 10 2.05 1.708 1025 159 865 15 1.58 1.312 1181 239 942 20 1.31 1.088 1306 319 987 25 1.13 0.941 1412 398 1014 30 1.00 0.836 1505 478 1027 35 0.91 0.756 1589 558 1031 40 0.83 0.694 1665 637 1027 45 0.77 0.642 1735 717 1018 50 0.72 0.600 1800 797 1003 55 0.68 0.564 1861 876 985 60 0.64 0.533 1918 956 963 Walton Homestead Subdivision - Basin 18A 27-Jun-03 0.407 = BASIN AREA (A) 0.567 =COEFFICIENT OF RUNOFF(C) 0.105 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cu ft) (cu ft.) (cic ft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.393 118 20 98 10 2.05 0.251 150 41 110 15 1.58 0.193 173 61 112 20 1.31 0.160 192 82 110 25 1.13 0.138 207 102 105 30 1.00 0.123 221 123 98 35 0.91 0.111 233 143 90 40 0.83 0.102 244 164 81 45 0.77 0.094 255 184 71 50 0.72 0.088 264 204 60 55 0.68 0.083 273 225 48 60 0.64 0.078 282 245 36 Basin 19A 27-Jun-03 0.254 = BASIN AREA (A) 0.482 = COEFFICIENT OF RUNOFF(C) 0.068 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) 0101r) (cfs) (cu ft.) (cu ft.) (cu ft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.743 223 31 191 10 2.05 0.473 284 63 221 15 1.58 0.364 327 94 233 20 1.31 0.302 362 126 236 25 1.13 0.261 391 157 234 30 1.00 0.232 417 189 228 35 0.91 0.210 440 220 220 40 0.83 0.192 461 252 210 45 0.77 0.178 481 283 198 50 0.72 0.166 499 314 184 55 0.68 0.156 516 346 170 60 0.64 0.148 532 377 154 Walto 'omestead Subdivision - Basin 19 9-Jun-03 1.312 = BASIN AREA (A) 0.693 =COEFFICIENT OF RUNOFF(C) 0.269 = HISTORIC RUNOFF (H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cult.) (cuff.) (cuff) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 2.925 878 81 797 10 2.05 1.864 1118 161 957 15 1.58 1.432 1289 242 1047 20 1.31 1.188 1426 323 1103 25 1.13 1.028 1541 403 1138 30 1.00 0.913 1643 484 1159 35 0.91 0.826 1734 564 1170 40 0.83 0.757 1817 645 1172 45 0.77 0.701 1893 726 1168 50 0.72 0.655 1965 806 1158 55 0.68 0.616 2031 887 1144 60 0.64 0.582 2094 968 1126 Basin 20 9-Jun-03 0.519 = BASIN AREA (A) 0.575 =COEFFICIENT OF RUNOFF(C) 0.103 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/hr) (cfs) (cuff.) (cuft.) (cuft.) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.960 288 31 257 10 2.05 0.612 367 62 305 15 1.58 0.470 423 93 331 20 1.31 0.390 468 124 344 25 1.13 0.337 506 154 352 30 1.00 0.300 539 185 354 35 0.91 0.271 569 216 353 40 0.83 0.249 596 247 349 45 0.77 0.230 622 278 344 50 0.72 0.215 645 309 336 55 0.68 0.202 667 340 327 60 0.64 0.191 687 371 317 Wa t Homestead Subdivision - Basin 21 9-Jun-03 0.584 = BASIN AREA (A) 0.696 = COEFFICIENT OF RUNOFF (C) 0.128 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (inl7z r) (cfs) (cu ft.) (cu ft.) (cu ft.) -------------- -------------- --------------- --------------- --------------- --------------- 5 3.22 1.308 392 38 354 10 2.05 0.834 500 77 423 15 1.58 0.641 577 115 461 20 1.31 0.531 638 154 484 25 1.13 0.460 689 192 497 30 1.00 0.408 735 231 504 35 0.91 0.369 776 269 506 40 0.83 0.339 813 308 505 45 0.77 0.314 847 346 501 50 0.72 0.293 879 385 494 55 0.68 0.275 908 423 485 60 0.64 0.260 937 462 475 Basin 22 9-Jun-03 0.316 = BASIN AREA (A) 0.607 = COEFFICIENT OF RUNOFF (C) 0.096 = HISTORIC RUNOFF(H) I0 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) (in/lir) (cfs) (cu ft) (cu ft.) (cn ft) --------------- --------------- --------------- --------------- --------------- --------------- 5 3.22 0.617 185 29 156 10 2.05 0.393 236 58 178 15 1.58 0.302 272 86 186 20 1.31 0.251 301 115 186 25 1.13 0.217 325 144 181 30 1.00 0.193 347 173 174 35 0.91 0.174 366 201 165 40 0.83 0.160 383 230 153 45 0.77 0.148 399 259 141 50 0.72 0.138 414 288 127 55 0.68 0.130 429 316 112 60 0.64 0.123 442 345 97 Wale Homestead Subdivision - Basin 23 25-Jun-03 0.878 = BASIN AREA(A) 0.657 = COEFFICIENT OF RUNOFF(C) 0.152 = HISTORIC RUNOFF(H) 10 yr. Developed Developed Historic Time Intensity Runoff Runoff Runoff Storage (min) 0101r) (cfs) (tuft.) (tuft.) (tuft.) --------------- --------------- --------------- --------------- -------------- --------------- 5 3.22 1.857 557 46 511 10 2.05 1.183 710 91 619 15 1.58 0.909 818 137 681 20 1.31 0.754 905 183 722 25 1.13 0.652 979 229 750 30 1.00 0.579 1043 274 769 35 0.91 0.524 1101 320 781 40 0.83 0.481 1154 366 788 45 0.77 0.445 1202 412 791 50 0.72 0.416 1247 457 790 55 0.68 0.391 1290 503 787 60 0.64 0.369 1329 549 781 1200 140 120 W °\ cn w f- 1800 :I:00 z t- z w w w t= 2..:600 a 80- _ ;� cwi a � G U. w. p 400 _ :60, cr a L`' 200 w 40 0 O 20 C - 0 FIGURE I-1 TIME OF CONCENTRATION (Rational Formula) 28 0 W LO U N 'ZI, 00 N X �x M V� �G N C O O � CD C/) w w LO WU L ':juZ�- a p O v'i O N CD O rGQ. Q LO z ,Q W o� =5 o � � Lo z coz Ems- z U) �3 m ww a N LO }- .p' N z 'm J C L ¢ NIL d z O N r O p C) r O Cfl tO C7 CV r O �=H N::Icl S3.1-13NI NJ JIIISNDIN1 lld�NlbZ{ .FIGURE I-2 RAINFALL INTENSITY-DURATION IN MINUTES 29 ' µ nJ W I � o - � e00 e e w e .� �O i CD X �+ �" �' 5 ✓" N 'h 0 U Q2 CO " � � ` o C'4N � z LO ! r Q i CO c- Q v! 73 Q zW iW- N W 7 zm o uQ. C `� C o i N � O r. O co Cfl N r O O O O O O O O O O �JnOH Ndd SDHONi NI kJ-lSNj1NI 11VANMI - FIGURE I-3 RAINFALL INTENSITY=DURATION IN HOURS. 30 to M r- M 4;r N LOr a -,T LO '-I- V' It It M rl- M f,- LO It M M a (0r M (PN r d "l: C) r Lr) - r"-: r--: *,t 04 ") co 't O " t- 00 't a, LO r N M 0 It C) C) 0 C) - C) CD - C) - a N C) 0 C) 0 0 tj q- LO (0 m w 'T C, w w I'- t-- N N C> I-- tj a O r C) (D M 0 W r-- (D N (D M r- M 0 M M N 0 .t3 Q 4 - CO 4 6 N 6 6 6 w - 6 m 6 m 6 6 6 4 N N CN r - C14 - - - - - - - - - r - - - - - - - M CD q- M I'- N rl- M N r M CD m cY M M N M N W M w 'I- m N 1* LO 10 "t -,t 'It r- m ID m 'I- m " (n LO m w ttl N LO r N LO Co 0 M - 0 CD (D 0 0 0 r (D a 0 0 a 0 C) 0 0 Z M M tl- 0 M 'IT Lo 0 (0 M LO r- m m - W W M M 0 W M M 0 M LO N M N M - V* N (D M C) M - (D M N r- 'It M C) "T - "T M M LO M q- r- M �T 0a) M0) N LO - N00 LO CO - 0 - r- M IT CD r- t-- - 0 LO V' t- CN M - OC) C\l - 00 (f) a) 00 r- 00 C) M (D (0 r- a) CN I- (D P- rl, - C14 LO M CO C) LO M OD cl) to N Cl) LO - to - CN C\) r M C; C) Q W 0 M it 00 M W M LO M W M C' m cf) It N CN LO N 0- CI N J N cl) Cl) Cl) - N Cl) N Cl N) -W C\j N N - - cl) C14 cl) 0 0 to (o N 00 0 O 't- N m Q it C4 ) (o N 00 0) Zt o N CN N N p M O ,..t O O _: cm M N t N � � o wtri o Og ii U m °v CO Q tl NN CO r 'v ain 0 E Y C `~ 3� � o 0 a+ C wo- CNN �m0 -b s MM Q tSM AMMtM Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Subdivision Comment : Walton Homestead Sub. - Det . Outlet Pipe Solve For Full Flow Capacity Given Input Data : Diameter. . . . . . . . . . 1 . 00 ft Slope . . . . . . . . . . . . . 0 . 0050 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge . . . . . . . . . 3 . 28 cfs Computed Results : Full Flow Capacity. . . . . 3 . 28 cfs Full Flow Depth. . . . . . . . 1 . 00 ft Velocity. . . . . . . . . . 4 . 17 fps Flow Area. . . . . . . . . 0 . 79 sf Critical Depth. . . . 0 . 77 ft Percent Full . . . . . . 100 . 00 Full Capacity. . . . . 3 .28 cfs QMAX @. 94D. . . . . . . . 3 . 52 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Subdivision Comment : Walton Homestead Sub. - Det . Outlet Pipe Solve For Full Flow Capacity Given Input Data : Diameter. . . . . . . . . . 1 . 00 ft Slope . . . . . . . . . . . . . 0 . 0100 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge . . . . . . . . . 4 . 63 cfs Computed Results : Full Flow Capacity. . . . . 4 . 63 cfs Full Flow Depth. . . . . . . . 1 . 00 ft Velocity. . . . . . . . . . 5 . 90 fps Flow Area. . . . . . . . . 0 . 79 sf Critical Depth. . . . 0 . 90 ft Percent Full . . . . . . 100 . 00 Full Capacity. . . . . 4 . 63 cfs QMAX @. 94D. . . . . . . . 4 . 98 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Subdivision Comment : Walton Homestead Sub. - Det . Outlet Pipe Solve For Full Flow Capacity Given Input Data: Diameter. . . . . . . . . . 1 . 25 ft Slope . . . . . . . . . . . . . 0 . 0050 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge . . . . . . . . . 5 . 94 cfs Computed Results : Full Flow Capacity. . . . . 5 . 94 cfs Full Flow Depth. . . . . . . . 1 . 25 ft Velocity. . . . . . . . . . 4 . 84 fps Flow Area. . . . . . . . . 1 . 23 sf Critical Depth. . . . 0 . 99 ft Percent Full . . . . . . 100 . 00 Full Capacity. . . . . 5 . 94 cfs QMAX @. 94D. . . . . . . . 6 . 39 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Subdivision Comment : Walton Homestead Sub. - Det . Outlet Pipe Solve For Full Flow Capacity Given Input Data : Diameter. . . . . . . . . . 1 . 25 ft Slope . . . . . . . . . . . . . 0 . 0100 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge . . . . . . . . . 8 . 40 cfs Computed Results : Full Flow Capacity. . . . . 8 .40 cfs Full Flow Depth. . . . . . . . 1 . 25 ft Velocity. . . . . . . . . . 6 . 84 fps Flow Area. . . . . . . . . 1 . 23 sf Critical Depth. . . . 1 . 13 ft Percent Full . . . . . . 100 . 00 0 Full Capacity. . . . . 8 . 40 cfs QMAX @. 94D. . . . . . . . 9 . 03 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Homestead Sub Comment : 21" RCP Storm Drain Pipe from Walton Way Solve For Full Flow Capacity Given Input Data: Diameter. . . . . . . . . . 1 . 75 ft Slope. . . . . . . . . . . . . 0 . 0040 ft/ft Manning' s n. . . . . . . 0 . 013 Discharge . . . . . . . . . 10 . 02 cfs Computed Results : Full Flow Capacity. . . . . 10 . 02 cfs Full Flow Depth. . . . . . . . 1 . 75 ft Velocity. . . . . . . . . . 4 . 17 fps Flow Area. . . . . . . . . 2 .41 sf Critical Depth. . . . 1 . 18 ft Percent Full . . . . . . 100 . 00 Full Capacity. . . . . 10 . 02 cfs QMAX @. 94D. . . . . . . . 10 . 78 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Homestead Sub Comment : 21" PE Pipe-Basins 7, 9, 10 , 12 , 13, 13A, 14 , 14A Solve For Full Flow Capacity Given Input Data: Diameter. . . . . . . . . . 1 . 75 ft Slope . . . . . . . . . . . . . 0 . 0050 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge . . . . . . . . . 14 . 57 cfs Computed Results : Full Flow Capacity. . . . . 14 . 57 cfs Full Flow Depth. . . . . . . . 1 . 75 ft Velocity. . . . . . . . . . 6 . 06 fps Flow Area. . . . . . . . . 2 .41 sf Critical Depth. . . . 1 .42 ft Percent Full . . . . . . 100 . 00 Full Capacity. . . . . 14 . 57 cfs QMAX @. 94D. . . . . . . . 15 . 67 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Homestead Sub Comment : 21" PE Storm Drain Pipe - North End Block 4 Solve For Full Flow Capacity Given. Input Data : Diameter. . . . . . . . . . 1 . 75 ft Slope . . . . . . . . . . . . . 0 . 0050 ft/ft Manning' s n. . . . . . . 0 . 010 Discharge. . . . . . . . . 14 . 57 cfs Computed Results : Full Flow Capacity. . . . . 14 . 57 cfs Full Flow Depth. . . . . . . . 1 . 75 ft Velocity. . . . . . . . . . 6 . 06 fps Flow Area. . . . . . . . . 2 . 41 sf Critical Depth. . . . 1 . 42 ft Percent Full . . . . . . 100 . 00 0 Full Capacity. . . . . 14 . 57 cfs QMAX @. 94D. . . . . . . . 15 . 67 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton Homestead Sub Comment : 30" RCP Storm Drain in Oak St . Solve For Full Flow Capacity Given Input Data: Diameter. . . . . . . . . . 2 . 50 ft Slope . . . . . . . . . . . . . 0 . 0030 ft/ft Manning' s n. . . . . . . 0 . 013 Discharge. . . . . . . . . 22 .47 cfs Computed Results: Full Flow Capacity. . . . . 22 . 47 cfs Full Flow Depth. . . . . . . . 2 . 50 ft Velocity. . . . . . . . . . 4 . 58 fps Flow Area. . . . . . . . . 4 . 91 sf •Critical Depth. . . . 1 . 61 ft Percent Full . . . . . . 100 . 00 0 Full Capacity. . . . . 22 .47 cfs QMAX @. 94D. . . . . . . . 24 . 17 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 CHART 2 180 10,000 168 8,000 EXAMPLE 6. 156 6,000 0=42 inches (3.5 feet) 6 5,000 a=l2o cfs 5. 144 6. 5. 4,000 * HW 132 D feel 3,000 5. 4. (1) 2.5 8.8 4. 120 (2) 2.1 7.4 2,000 (3) 2.2 7.7 4. 108 3. 3*D in feet 96 1,000 3. 800 - ---Y --->- 84 600 j 2• 2- 500 72 400 a 2. � 3 _ 300 E� / = 1.5 1.5 N 60 0 200 / 1.5 z / w_ 54 a z .: ,7 ,, 0 0 )�. ~ w L00 w 4 8 ca — a _ 60 I.0 LU- LL.c� v _ /2 rn 50 HW ENTRANCE O O o 40 D SCALE TYPE w - 9 9 H 36 30 (I) Square edge�wit Q w heo all 9 � O Q 33 roove end with w 2 0' headwall _ $ $ 30 6 iP(2) Groova end 27 j projecting F T T 8 ? 24/f% / 6 To use scale (2) or(3) project J 5 horizontally to scale(1),then 4 use straight inclined line through D and a scales,or reverse as •6 .6 3 illustrated. .6 18 2 15 5 5 .5 1.0 12 HEADWATER DEPTH FOR HEADWATER SCALES 2&3 CONCRETE PIPE CULVERTS BUREAU 6F PUBLIC ROADS JAN.1963 REVISED MAY 1964 WITH INLET CONTROL 5-�22 ?'� L�T�'�;r• -:-'T�{..i �, y �k-.R.V��F � _' S„<?a � ,I i'r.,'S�:'�'' � 5 .f= r= 't art•_, r�� L r :■� it z ,�_ - , y Jti :{ ', ice■' �-T' ?����� '`� 7 'r= ,_ �■ Y•• ' ' ,r_✓t-'- Ir'�d_ -S _f'i. _.���� ice - •• t �� ; �.,--_ -t _ T r- �'- �[�_� �.'_..�_ ,,.,�. }�� rr tip- L S,'�Trrr _ �..¢�:—• *� ,3: - t I - •■., ,t1 �. j1- ,tip- 'ry:, Y" _ -i- �_ _ I .Y-a-t-s" -, :r.� �'„tea^ `-�-1 -. •4, _ C {y i i 'air _ . _ .,,-2 i a��', ,_,s-• �`�, _ .J7`. teyr'_■mac 1 .�.-S#_] •'■ ,4'-a� r �� �K' - fie ' •r s'l■M �� 7 I_„_v_ •GI:�� �,. "t�i-1- �' - �� -� r'-'. 1 'T_a_ J ��7 p� -r S, `41,I "-q,',�-. _ ,,��� [ sr�■--,r_■L: J ��_, _� ��'.■• l _Yr .r i.I11 ■ > > '-�{-•fJ�_�:•;J __ _ ,i i•ri_ - ,L�, '_S L- ':- y� I S1• •1'IF r; ,-AT f lr'L'rrr ,ti ��� r. }!•'T .1.• _ 1. r � r .Y� - •+_ r 11 tiV a •t �L { u411 �ri7 r� r r = r 7RI 1 4��,' 7 - lr � r_. If`, :, rM• � ■ � „' 7 � 4r 3 V fir+ �'" • i Cam?' N,� :T •_yL r. ��i�� ,� 1 T'�f- 1 r'� �r- ■ ti u�,�' 1 '�,r •.?��� ti� - �� �it ' L Q r=ti., _� -', ,:F_+1 ,�: N PL-5 � .•yet �+Er T 1e•�.~•l'�' •�� x :rl� I� k 'c- I`c' - i - '�,Y,Y.'.�'� _ ,�{�J •�� �� SLj'!. _ y R . y�_ 1 L'.• Y: -R 'c 't•'_ � ~'�s,'rr" ��J� _%.�' r- i�-� •�G ITS -'ram. -��;•_7 I� PI �- -"��' �� SY=- I - ��y.L�x1' ��y_�"�•�'~ J ��_',„ Y F` -_r_ r' _.�,- ■ .L!a l�.r■'. �'`�a�.r c:+� '�=. .�' !E..? � •�1. �4 ts:°�_` 1 fw �" ._: - {'#1 �iPJ- ~''k. sF� re rl w' 7 '_,'r -JK 5 -��� i -0'�,...4�, J� F-',�j`7r fj;-!__■ �=,•, '1 '+-- r'#7�J� �__�'ir. �, �, !-. .�."T r �''.- tip- _ -rr y= J:, -,��A', ��' '•'L a' ,�' aj-ti --r.�_ i"�.■� y �-r -•••c � �i�` I 7\-�� ti3-�� c�.. ..tip � „� �,-. .,. r• r, -,:-'f�• '-`� -t'J-.�,�5 ':r��' �r �-• L'-5[YTi� r• CAI R: - - • ��- 4 <. r,r���•ti _ ■ _=a r� 7.,_ r- =`� ��__�'S`���'-.;'} r.-:' ■•i � _': S - -� ,'',-� �_� _ _1 I '1-'7(77•r_ , �i1i '3,1_ , ,ti. a+_r,-,� -=.7=-. � '�r :�r. II __r �• - - - }t'u_ ,i, _ _ 1 _S -f, ,;'- ,'s_., _ LT': _ I:. .qr__ _ LI-'_ l- ._ _,_`-1 _ IG�'Ai =F-�,?' I _ `� J ��',`.`1-j1,_C��• - ,rx,• �I��� _i r .■ I -r7:r ',�.ti,7rf ;`;,_� '.- �■�- 17�'I y� t��'-I+c":•,7:.. - _ _ �_�`� _,4{ _ _0�'• �_� :I' r ' ,_ ?:} L• �- xrrl-5^,. 2,1�'��`��r,J.'F K_ s. � �-'7'' �!^r►J "^'," � �'F�i' � },. Y;•�.� y4,�': r'.�r 1l �, .E �.•r J_• _= j L,t -�J�''ij� f 1: 'f4�*= .I. _ ti• iF r J '17[ 7� �,4',•. I� r _ _.Q .-r'�'-[J ti,•�z?-,- `` �-�:�•J...'n.'., li 1' V- ..� ■ �_- - -f',f '_ �i __ - '•� - YJ FI'' � 1•' - .rr�' -ram_ r_-Jt= J�' _ �J. _ -r _ �1 �- s �: 1�- -J _s_y._,.'.`-'= ram:,_i .,�-'-,/�- ' •F_,,___.. � ■ +■� -ter_, '-'xt5',` T• r =4 �_�=�4, �� r 'i •'~ 5�-�-• .gyp„ t~' - _- 1- .� w - '� . of 1 �_r+-, .'�_ ._J; _ �- C , r ti, - r.�.r r��•,�' �:, '.r •YL;F_= .'� ,`71 _ I. � ,�: : '.T F. J. .��r,�1��-�+r r r �ti 4ti �r,"�� _ ram_•-�,•-y t` 1:-,. ,i. I'' -� � �l; _ _1 ..•J - ' r r S� .3.'.rx - -a�' l ��_i}R:�, �i I,,� F T '`Y'i-._� - �..:5-a`l y► RY. r, V"I L'J-~I ifJr 4'� �yl_,'�_=2 _� S-.�'c, _.:- 1T-L'r 1. •F} - s T�;'t Ti ■,� � �_ -�. i ..,zi•t F�....- �'• -_"-rlle'• _ ��,rv�N�e -L-r.� = r F �i: � s f �, y x ��.:•.% i• /�T b-T. _� \ c' L t3t' � 81� .: �1 f-•. ���� . `t..lOti `�♦ +�. 5. t_ 5 _ ...,o.s c_ "" .,'.r..... w �.we..rrL � 9�t•'�. 1 :_ -i � ,a x 1 - t, .r ww .� r�y KI T �.. am .a.. . Mm -• y: i - `• ( .'S _ � "c -tti C 4 y - a '•!. . ••� . e--' `y -ASZ. R1- .-.-' ` Z Q OW N I "s-�. ♦ t.z�.x• a'-: f E'.:r �y �,r.vv�.x t' ��:'�:"" x 1 � a.-< � �Y. t fill '!• '� �r ; �� ��� Tx 5..: � f>��r- '� t �t $:J� •sL 1iy:� �� `E_ WWIN �'. �, �'S ���0\ \ �. ':. ..3 ± - �J� �.•,.y� � 1 �~T L� 1'.L :`Y� .L x s S. 0 Co '•y 'e "eS<asfi3r-_-�•.: �'e '•r.r i - _ _ ..` _ L••�i- - .' 'L. . . O .. :,.. �,-ks_,,,:-. F '�.-'_-?`_ o •.?�l"`.w`a�' x,..:cP'_ . .¢Y<*'�t�. T : .'�7 t3 �if.��..:. .=.-{! .. _ _.._.�,- 3 T... x3: ,-,,: .. : ,1: .. A•Y. _ �/_ _ - •_ram c'• - HIM.- :. '_•,.i ter.:�.- .:>`' <. •'. z.- .,...........:. •: ��-s�. '- 1 _ •.r _ H , d ' . f1N3AV / 3fN�r`v°` #� 81 g rc -: .1 r.5. .,r.� ., :, ',';` .....'-'.,:' �=.• _. <3-'.ss n+r r-r.lrr'r..rreu_ei_cni'r r `�- _ w. �I :� i. i. 2.. � � �:•_ - � tr � ,.� .._312'� .ks., �`L � '..p'�61' {_ y`k;`t�" S.sS,` ,Yh �(' i,.'. > ,.�.i-.�,.. -i1_ � '. � '•_ :� '?. .- � ': -• �': {(.-; .Yl_ 'p?�' ;try. �i •! l yF�F,� '�,^`�',. ...:!._' • r ..'t :. ^� ... ..' .te- I� .: �.• # .-. '.. I \ Z .,,.:.. YT -,::� � M T. F - ?3• ._%l� {jj�� � 1 �����))''tt ��,;:,ij``JT� r(-n`:• "2'> .�" 6' In LL_L x: s : .. .. .. _.... .\ ,. ,-_ ...-.�.;.�..., 1. '• .'9•__.. 'T_ ,:C'� .t`l. 8 tC?" -:T,,n �•rJ_ C� Piz , .., .. r ,-. -,� .t.+ __,♦. .:_. ..+-.. : � . .. ,-� a-.�-::;. ';s>,.r .•�'� _ 'r1i .t x:t :x. PI -'{:RM :'1 re - .� y. - .. .. .. (): \:' � _ �� jf{l,.\f/`� •�i__'�d, .''^"i .':�- 4-=�a.., -- _i Ei V it ..3t �'x t _ L. .'?'ry�.- t �'- ^.-„��� -*yam•=re>-x. .y�'£a:s - 7,;.Y"'-; ",a:�_. 'Ly ,_ � `�'-�• - ��. � 'F _ i E- 1t. _ .-4�..•. ,r .� ^v '-tG ,•�.� _" r :a r.. '��. t C't - 5:, r� �= z o - • \ y `w_,._ !� ._ •I _. ,.., .. .. . '�!'. ...... :. .h.- ..,_ .L. ..:.: :r ..-. �. z-Y '.?s �: %',s,�'+c•�s, .-t �su� F:.r..a e. p *�i. ,, �..+,. �i t,•a - �.` 'P,��1 +1 1 =.�?L. s• �. ! J- .a, h. Yam,.-�• ,k ���i,��• n. .1' -�k :�:`' •i'�:- 1 '-��.^�"-.�E _ �.+�, •;'L:*t t_ �,� -5.. � n :... .. i. iti"v---C. 5� ::r�s�•Y�`{T.� _ _ �� V�:r_. O,`. '.3 - 4•" 'r•a-, ... w- .�� : '..- .. .-.,� .... .: .. .. .,: , _,... � .m. > � -, � .. t.•., ..y, _ `;ems_ i�a. { �j,�l� f �.: .:.�_.�'> '.'.'.r �� r/.•,.1`..,',♦ -.1:.., �'R"- �?:" r5^ }x•-r'iCt� H`. Y3'i A'�.§ _ f - ,...r,. �^�• -r1 �- �y?.' -•Ft+' l.. '':yt '� ,a :° i�i.k X�"' .,-. c:L`- j-•-"r.- f t-'sr A'k R� 1 r 'r - Viz.:•' �c k' - 11 Val•' -=b'•�.- ''�` �. 4 _ E — Rq 0 N� I i L���. (�r��� - F.. {y�ry.'.. '1,L': _ -�,-y-�:.,�' -� {�,�:.t'.4: Y'•'f"fl- / a '"„ - :'.�':,:-^-`�. - .� ♦ f :x':-�. �VNFE� S2,�tN Vd "t, .S.t"..e - '�i�v.-+.T''♦-'I a Q S9 X O£ „SQE X o£ 30N3AV �— t £L X,S� FI1N3313N{N O Y s cu N x i N i "'!—'� X- b l: t t_ 1 04 -40 ch CL £L X„SIs, I f xFf-, r` ;,,,--s".�' {'' � \i•- •� �„' C - - 48I ... St SI I ( J �191t0 NOIlVJl2iiil � gt k s err, M L G j/r rra _��T t � L �L'_C.�-_ [,`�_ �-- ✓� L-- L.� G� ' ` �?. �',�`.�� zr , ,� r= `\.Z L N '?r 7 •c� Q O ; t�6 9£ ,Z.Z k _ tQ, 0 � N; II �:� {r T 0 4— U? 0 (6 0ca _ E 1 W ddl, Z p 0 0 J Q U • U � W Z J U F— Q t LLr r i...Fl 4 S.. _ - .. r ".--.t - -•7 s '.'#'*!.r •.<: Y K - :4: 7 T .. v�{=Fz�.tiu' fv�i.°ii;`:gt+' 31 (' t .,:_gib r - 3nN3AV - -:,; - __ I -� _n+ �, R p r-R.,�..y .. ..:1. } _ a *.."fir ,�•t -x<� \ m s ate. � .,:� ... .. •.:z ':.:.:.: .. .. :.... ::'; � .. _,;.... ,^-S:.` ....-i :.:� ,.:`F. �� � __�u GG,,.. {��. ..: O�% i � �15% rs--''1�;: •1 h�� yt,�. t _ 1- cli r [ aat ....�.. 8 £<y .. 1 ,_ l � •,,,r , :,X. \, 7' X , .;I�__ I I. }ate'• 1 r. H0110>13383 IOQ:iW w is rl - nv- 81 -- p 3f1N3nV — H1 61 t z>< ...r ., - ,. +gin :._,.. ._ ._ .,. ., -. -, •:-•- r. __ Si>.._ v..:- r2sP-. t. r f , 3 Z ? i r . v- ^i _ w 4 .:.:, ,: � ..•�. -<•_ram.,<,. ,.... ... ..�'�<. ;.:+........ `'F�� �,,.-. 't- '+f � � r r.>!Ei_a eti..ra _:. �:, .....:-: ... ._._. .. _..`e.._ ._. -, ..,, _.__ -. _.f•. ,..; . ems•.. _ :�.. .:-`x�'• -rS } 'hi ... '-.. ,' .,>' .-tia:.:�: .: ,.. .._,., _ ,. ... ......�- ,.r..r :. .-...,,i .,. ,,:,.._u - _ .x-.. #' •J ..+ ,.:Y.x 'r�ri�z.+ Q O } W � Z F21 U H Q - TABLE 5. COMPUTATION SHEET FOR CHART METHOD PROJECT ��✓�; r a J �t !� p,.> `��J Computed By '' , Date Checked By Date 1. Required Input A = 3 3* Acres Drainage Area T = 2 6- Years Design Frequency (return period) P = 2.3 Inches: Rainfall depth for 24-hour, T-year event Y = t_¢ % Average watershed slope CN = 07 Runoff Curve Number 2. Compute Volume of Runoff, Q Q = ©-r' r Inches: Use CN and P as input to Fig. 5 3. Watershed Shape Adjustment (Optional: if adjustment is not made, set EA = A) HL = /?,mac J feet Hydraulic Length EA = Acres Equivalent Drainage Area (use Fig. 10) HF = 0_ 3- HF = A/FA 4. Obtain Unit Peak Discharge, QU QU = j,/G! cfs/inch Q : Use EA with Fig. 11 (Sheet 1, 2, and 3 for flat, moderate, and steep slopes, respectively) 5. Watershed Slope Interpolation Factor, SF (Optional: if adjustment is not made, set SF = 1.0) SF = /-/;7 : Use Y and EA with Table 7 6. Ponding and Swag Stora e Adjustment Factor, PF (Optional: if adjustment is not made, set PF = 1.0 PPS = / % : % of Ponds and Swampy Area (Based on actual drainage area A) Location in watershed (check one): Design Point (6-a)_; Center or Spread out (6-b)—; Upper Reaches (6-c)_ PF = / : Use PPS and T with Table 6-a, 6-b, or 6-c. 7. Peak Discharge QP, Calculation with Adjustments QP = QU x Q x HF x SF x PF _ 14-4 x o,8.9�- x 0.3 7 x I /Z x Z- 0 _ .53 cfs 8. Modifications for Urbanization IMP = b % Percentage of Impervious Area (based on actual drainage area A) IMPF = /_ 3 Impervious Area Adjustment Factor (Fig. 12) HLM = % Percentage of Hydraulic Length Modified HL4F = — Hydraulic Length Modified Factor (Fig. 13) QPU = QP x IMPF x HLMF x /_ 3 x _ �9 fs 29 TABLE 5. COMPUTATION SHEET FOR CHART METHOD PROJECT J -5✓iZ_ Computed By e Date Checked By Date 1. Required Input - A = 53-el- Acres Drainage Area T = /O-0 Years Design Frequency (return period) P = 2.9 Inches: Rainfall depth for 24-hour, T-year event Y = /,¢ % Average watershed slope CN = P_ Z Runoff Curve Number /— C^.✓ ou/� �' 2. Compute Volume of Runoff, Q �'-:5 �? SiFi ���F' d' �¢° /�� `: ca J? l Q = 1. 2 Inches: Use CN and P as input to Fig. 5 3. Watershed Shape Adjustment (Optional: if adjustment is not made, set EA = A) HL = /2, E00 feet Hydraulic Length EA = q d pd p Acres Equivalent Drainage Area (use Fig. 10) HF = (9-,:,,,7 HF = A/EA 4. Obtain Unit Peak Discharge, QU QU cfs/inch Q : Use EA with Fig. 11 (Sheet 1, 2, and 3 for flat, moderate, and steep slopes, respectively) S. Watershed Slope Interpolation Factor, SF (Optional: if adjustment is not made, set SF = 1.0) SF = / /7 Use Y and EA with Table 7 6. Ponding and Swam tora e Adjustment Factor, PF (Optional: if adjustment is not made,�, et_ PF = 1.0)_ PPS = / % : % of Ponds and Swampy Area (Based on actual drainage area A) Location in watershed (check one): Design Point (6-a) ; Center or Spread out (6-b) Upper Reaches (6-c) PF = /- Use PPS and T with Table 6-a, 6-b, or 6-c. 7. Peak Discharge QP, Calculation with Adjustments QP = QU x Q x HF x SF x PF 144- x /,Z x D,37 x / /7 x /-o -/,:S- cf s 8. Modifications for Urbanization IMP = �10 % : Percentage of Impervious Area (based on actual drainage area A) IMPF = /3 Impervious Area Adjustment Factor (Fig. 12) HUM = % Percentage of Hydraulic Length Modified HLMF = : Hydraulic Length Modified Factor (Fig. 13) QPU = QP x IMPF x HLMF 7S x / 3 x — _ —cfs 29 CQ z 9 CV In Z co E. > > L) C-4 'to z C14 z ZD E" z z per, L) �ICN ro 4-) CIO 4- U) 4-) co, 0 co o, c C\J 4-) CO 1c, m CL Q) Lc)(\j 0- r LO -4" C14 C-0 CO co CN Ln C4 r�-,N i co CN co j n v� o m U co f 00 - - - - cy - — - - - 9< 0 H. - -�- 8 J w O N N _ Cd 0 0 _- 2 � _;p - - - — — Z W 0-a_ .J - 06 44 d nr - - _ to — o - J 4 —0 Al _'O m- - N _ - -- _ n- L-IN N CD _ — IFrt D -_� N OCY - - Wl V) - _�;'� o0ii a' + ...a �. . . J _ _ - LC LL a a U CC O _LL " z c o - - -- ` • a Y H f-- E - - - N v u Iz c J � u c _ v ' O a co M N — Q S3NON1 NI (6) 33ONnu 103810 u 17 i Circular Channel Analysis & Design Solved with Manning' s Equation Open Channel - Uniform flow Worksheet Name : Walton 36" RCP Comment : Walton Homestead Sub. - 36" RCP Solve For Full Flow Capacity Given Input Data : Diameter. . . . . . . . . . 3 . 00 ft Slope . . . . . . . . . . . . . 0 . 0080 ft/ft Manning' s n. . . . . . . 0 . 013 Discharge . . . . . . . . . 59 . 66 cfs Computed Results : Full Flow Capacity. . . . . 59 . 66 cfs Full Flow Depth. . . . . . . . 3 . 00 ft Velocity. . . . . . . . . . 8 . 44 fps Flow Area. . . . . . . . . 7 . 07 sf Critical Depth. . . . 2 . 50 ft Percent Full . . . . . . 100 . 00 0 Full Capacity. . . . . 59 . 66 cfs QMAX @. 94D. . . . . . . . 64 . 17 cfs Froude Number. . . . . FULL Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 r_ M U U � J o ' 0 d U z F- z Q Y Z U U� O a F- x ¢ as llj _jY Z= Q w� > C 7 Z W I-U c9 a^ a cn UJ < Lt1 a N J \ O x x 0 w U = JZ Yd � U x 1 0U m 3 ._j U U J W — w W WE h 2 r t f ( c ~ W �Y W o< Z w� oN o W O _j ~ w� as 4 wo Ya a Jx x W a �� ' QLL_ O W �� �'\ o� oQ o rW-o 0 S` q o� \ W w } �v_ o F U _j (rI4 (A \ j>- i- f L�JLIUU ULIiILIUUUUUUJUULIUUU '� _j / =oE!IMDQD00 0C IDUD[1DD Q •-- �. I I,� aO�Qnu00000 00o== it mo _j r� -' oo0o00oo oo.n�-1� J r ■ =000a0000000��;� I ' �fn� U t ■ m II II II II�II - II■. * N - co d • �k l ■ ■ II • _ ait .r ■ I ` J x w a r m z w o a pF pomm x Z LL Z — '��TV1, II - p, 1 M It--,--_�—_— "'s-c;..��'� '� C.,,=:71 wOc�Y' 1 ■ - a !I IN I =_� • _ ,,�,.b i F "r- � £zr ✓s - fry- �. �, wi It tb II � ■I I ,. ■ 3� ''" ,�� ����+�;,..�.�` y ��`�I �^s i -*' s �� ;.y. it r: If 1 ,x U r; a' cq l( '• . - ,k s r,. r a VA - ,,s"..�-sue' a+. It ■I � Y W — W� It � t lu o J W Ea o / wiw w wN l r a;a cxi I"' p oK tea. F I F- j �_ o �� Jo O Ri , y x x I U U w to Z F m \ W U U z J 0 J c1j z ' U y V ~ ~ y z o Q w Q h a+ o I- lb a._ w � i N o x mU a� a N a a o w az w x o LL J O rQ LL o nm m o z z U < = W o E V _j� U X N Trapezoidal Channel Analysis & Design Open Channel - Uniform flow Worksheet Name : Walton Ditch Comment : Walton Open Channel Below 36" Storm Drain Solve For Discharge Given Input Data: Bottom Width. . . . . 5 . 00 ft Left Side Slope . . 3 . 00 : 1 (H:V) Right Side Slope . 3 . 00 : 1 (H:V) Manning' s n. . . . . . 0 . 035 Channel Slope . . . . 0 . 0100 ft/ft Depth. . . . . . . . . . . . 1 . 65 ft Computed Results : Discharge. . . . . . . . 72 . 63 cfs Velocity. . . . . . . . . 4 . 42 fps Flow Area. . . . . . . . 16 . 42 sf Flow Top Width. . . 14 . 90 ft Wetted Perimeter. 15 .44 ft Critical Depth. . . 1 . 41 ft Critical Slope. . . 0 . 0189 ft/ft Froude Number. . . . 0 . 74 (flow is Subcritical) Open Channel Flow Module, Version 3 . 08 (c) 1990 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708 VI. Natural stream channels-Continued Friction Losses in Corrugated B. 1.1Pedsturenno Mush.t to natural streams): Manning g n Metcalf,Corps of Engineers,Department etal of the Army;published in Journal of the Hydraulics Division,Proceedings of the American Society of Civil a.Short grew---------------------------------------- 0.030-.0,035 Engineers,Vol.85,No.HY 9,September 1959,Paper No.2148,pp.35-67. b.High grass_______________________________________0.035-0.05 t For important work and where accurate determination of water profiles 2.Cultivated areas: is necessary,the designer is urged to consult the following references and to a. No crop___________________________________________ 0.03-0.04 select n by comparison of the specific conditions with the channels tested: b.Mature row crops________________________________0,035-0.045 Flom of Water in Irrigation and Similar Canals,by F. C.Scobey, U.S. c.Mature field crops________________________________ 0.04-0.05 Department of Agriculture, Technical Bulletin No. 652, February 1939. 3.Heavy brush and trees: brush_______________________ 0.05-0.07 Flom of Water in Drainage Channels, by C.E. Ramser, U.S. Department 4. Light brush and trees: s of Agriculture,Technical Bulletin No.129,November 1929. a. Winter____________________________________________ 0.05-0.06 S Handbook of Channel Design for Soil and Water Conservation, b.Summer__________________________________________ 0.06-0.08 the Stillwater Outdoor Hydraulic Laboratoryin � prepared the 5.Medium to dense brush:t Oklahoma Agricultural Experiment Station, u cooperation with the a. Winter__________________________ _ 0.07-0.11 servation Service,U-S.Department of Agriculture, by the Soil Con- b.Summer__________________ _ ______ ___ 0,10-0.16 March 1957,rev.June 1954. griculture,Publ.No.SCS-TP-61, 6. Dense willows,summer,not bent over by current____ 0.15-0.20 !Flom of Water in Channels Protected by Vegetative Linings,by W.O.Ree 7. Cleared land with tree stumps,100-150 per acre: and V.J.Palmer,Division of Drainage and Water Control,Research,.967, Soil a.No sprouts___________ ____________________________ 0.04-0.05 Conservation Service,U.S.Department of Agriculture,Tech.Bull.No b.With heavy growth of sprouts________________ __ 0.66-0.08 February 1949. 8.Heavy stand of Umber,a few down trees,little under- r For calculations of stage or discharge in natural stream channels,it is growth: recommended that the designer consult the local District Office of the a. Flood depth below branches----------------------- 0.10-0.12 Surface Water Branch of the U.S.Geological Survey,to obtain data regarding b. Flood depth reaches branches________________ __ 0.12-0.16 values of n applicable to streams of any specific locality. Where this gro- C. Major streams(surface width at flood stage more than cedure is not followed,the table may be used as a guide. The values of 100(tJ: Roughness coefficient is usually less than for n tabulated have been derived from data reported by C.E. Ramsey (see minor streams of similar description on account of less footnote 4)and from other Incomplete data. effective resistance offered by irregular banks or vege- A The tentative values of n cited are principally derived from measur tation on banks. Values of n may be somewhat reduced. made on fairly short but straight reaches of natural streams. ements Where Follow recommendation of note 7 if possible. The value calculated from flood elevations along a considerable len slopes gth of channel, of n for larger streams of most regular sections,with no involving meanders and bends,are to be used in velocity calculations b boulders or brush,may bein the range offrom-----------0.02".033 Manning formula,the value of n must be In per c y el, Increased to provide for they the tioFootnotes to Table 2 per al loss of energy caused by bends. The increase may be in the range of perhaps 3 to 15 percent. for Estimates arementmAuofP Public Roads nle in ess oue therwise noted may be aand are for .creaseThe value of resence of a aTherefoe on trees nr ughnessbrush eoefficoentafo will nlin channel alinement other than straight. leaf will be larger than for bare branches. For trees in channels or on banks, t Ranges for secs. I through III are for good to fair construction. For and for brush on banks where submergence of branches increases with depth poor quality construction,use larger values of n. of flow,n will increase with rising stage. Table 3.-Maximum permissible velocities in erodible Table 4.-Maximum permissible velocities in channels channels, based on uniform flow in continuously wet, lined with uniform stands of various grass covers, well aged channels t maintained t = Maximum permissible velocities for- Maximum permis- Material sible velocity on- Water Water Cover Slope range Clear carrying carrying Erosion- Easily water fine sand and resistant eroded silts gravel soils sells F.P.S. F.P.s. F.p.s. Percent Sandy ndyloae sand (nncolloal)______.___ 1.5 2.5 1.5 Bermud 0-5---------- 8 6 Sandy loam(noncolloidal)____________ ____ t.7 2.5 2.0 �� {(5-10--------- 7 5 Silt loam(noncolloidal)_____-____ 1.7 3.5 2.0 (Over 10----- 6 4 Ordinary firm loam -- 2.0 3.5 2.2 Buffelograw-----____ --- ___ _-_-__ _ Volcanic ash------------ -- Kentucky bluegrass------ �---------- 7 5 ----- 2.5 3.5 2.0 Smooth brome------------ --- 5-10--------- 6 4 Fine gravel_________ ___________ 2.5 5.0 3.7 Stiff clay(very colloidal)___________________ 3.7 5.0 3.0 Blue grams Over 10_____ 5 3 Graded,loam to cobbles(noncolloidal)----- 3.7 5.0 5.0 Grass mixture_________________________ ��'------- 5 4 Graded silt to cobbles(coLloidal)___________ 4.0 5.5 5.0 S-'10'-------- 4 3 Alluvialsilts(noncolloidal)_______________ 2.0 3.5 2.0 Lespedezaser(cea_____________--------__ Alluvial silts(colloidal)------------- 2.0 3.5 3.0 Weeping love ---------------------- 3,7) Yellow blueste __________ Band shingles hn g eat------ __ 4.0 6.0 6.5 Kudzu--------__ ---------- 0-51--------- 3.5 2.5 Cobbles and shingles________________________ 5.0 5.5 6.5 --------------------- Shales and hard pans----------------------- fi.0 6.0 5.0 Aifalfa________-_-_____--------------- Craogass---------------------------- Common lespedeza e-------------------- I Asrecommended bySpecial Committeeon Irrigation Research,American Sudangrasss_ �5 3.5 2.5 Society Of of Civil Engineers,1926,for channels with straight alinement. For sinuous channels multiply allowable velocity by 0.95 for slightly sinuous,by I From Handbook of Channel Design for Soil and Water Conservation. (See 0.9 for moderately sinuous channels,and by 0.8 for highly sinuous cbannels footnote 5 table 2.) (46,.p.1257). =Use velocities over 5 f.p.s.only where good covers and can be obtained. pro Per maintenance Do not Y Use on slopes stleeppeer steeper han 5 percent is nott. Annuals,used on mild slopes or as temporary protection until permanent covers are established. 54 STORM WA TER MAINTENANCE PLAN Walton Homestead Subdivision Bozeman, MT 59715 The storm drainage control facilities for the Walton Homestead Subdivision consists of overland flow of storm runoff into detention areas located throughout the site. Some of the detention areas are ground level ponds, and some are below ground level pipe systems. The final grades for the subdivision have been designed so that storm runoff will flow unrestricted to the detention areas from the streets, buildings, driveways, and landscaping. The purpose of the detention areas is to reduce the peak runoff from the development, and to remove settlable solids, silt, oils, grease, and other pollutants. The outlets of the detention areas will discharge settled storm runoff to storm sewers or drainage swales, which will ultimately discharge to the drainage ditch along the west side of the property. Some of the detention area outlets will discharge settled storm runoff directly to the drainage ditch. The Owners Association will be responsible for maintenance of the storm drainage detention areas and outlet structures within the development. The Owners Association shall maintain and mow the landscaped areas forming the detention ponds. The outlet structure of each detention area should be checked periodically, and cleaned if any accumulation of sediment is found. The outlet pipes should also be checked for sediment and cleaned on a routine basis. Typically, inspecting the detention systems twice a year should be sufficient. Any significant accumulation of sediment in the detention areas themselves should be removed to retain capacity. No fill or other materials shall be placed or stored in the detention areas, as this will reduce their storage capacity.