Laserfiche WebLink
<br />CONTRO.:: <br />OQ <'", <br />o 1It',~. ij>..... <br />~ ~i!Ul ~ <br />c 0 <br />~ 1m ;t <br />~ 'J!J l <br />~~b'I:Ic tJ,'4# <br /> <br />Ii <br /> <br />II: <br />, <br />i <br />, <br />Ii <br />" <br />Ii <br />, <br />" <br />" <br /> <br />li <br />" <br />I: <br />I: <br />Ii <br />i <br />Ii <br />" <br />1'1 Executive Committee: <br />I: <br />Ii <br />IJ <br />I-I <br />Ii <br />Ii <br /> <br />Board 01 Directors <br /> <br />N <br />Calhy Reynolds g <br />Chairman 0 <br />City of Denver ~ <br /> <br />Ruth A. Correll ~ <br />Chairman Pro- Tern ...J <br />Cily 01 Boulder 8 <br /> <br />Sleven E. Cramer ffi <br />Secretary > <br />Adams County ~ <br />o <br /> <br />Arlen E. Patlon <br />Treasurer <br />Engineer ~ <br />Eugene l. OUs ~ <br />Member > <br />City of Englewood <( <br />~ <br />~ <br />W <br />N <br /> <br />Members: <br /> <br />~ <br />Robert BrOOkS 0 <br />Arapahoe County ~ <br />N <br />I, :;,' David A. Day <br />" Engineer <br />I; w. G. Duncan Dl <br />Douglas County ~ <br />i ,; Rich Ferdinandsen w <br />t Jefferson County t: <br />I,: Josie Heath ~ <br />i': Boulder County <br />I George A. Hovorka I"- <br />City of Weslminsler ~ <br />i Feder;co Pen. ~ <br />I' CIty of Denver ';/ <br />,! M. L "Sam" $andos w <br />t Cily 01 Denver 6 <br />I' Paul Swaim I <br />.; City of Denver ~ <br />I, R Sw W <br />Ii eJC ann I- <br />~ City 01 Edgewaler <br />I:: <br />, <br />, <br /> <br />, <br />I <br />1,[ <br />j! <br />,",: <br />" <br />! <br />i <br />,i <br />1 <br /> <br />l. Scott Tucker. EXOCUllyC Director <br /> <br /> <br />May 1, <br /> <br />~ <br />.~J". <br />V; '~ <br />C C'Q 0y./ (~~ <br />19{ilJ& ~O1l ./ {g "~7J <br />~~~bO 0'9' @' ~, <br />/OA~r>- '/ <br />'V6l <<'1' /' <br />V'11'b <br /> <br />TO: <br /> <br />All Holders of Urban Storm <br />Drainage Criteria Manual <br /> <br />Ben Urbonas ~~~2 <br />Chief, Master Planning Program --- <br /> <br />FROM: <br /> <br />SUBJECT: <br /> <br />May 1, 1984 Revisions to Manual <br /> <br />Accompanying this memorandum are the following May 1, 1984 <br />revisions to the U~ban Storm Drainage Criteria Manual: <br /> <br />1. <br />2. <br />3. <br />4. <br /> <br />Volume 1, <br />Volume 1, <br />Volume I, <br />Volume 2, <br />and 5.4.5 <br /> <br />5.4.4, <br /> <br />"RAINFALL". Entire Chapter <br />"RUNOFF". Entire Chapter <br />"STREETS". Revised Figures 6-2 and 8-2. <br />"MAJOR DRAINAGE". Revised Paragraphs 5.4.2, <br />of "Riprap" (Section 5). <br /> <br />Replace the revised chapters, figures, and paragraphs currently in <br />your manual with the accompanying respective chapters, figures and <br />paragraphs. I suggest you either void or destroy the old pages being <br />replaced. <br /> <br />Items 1 and 2 above represent a very comprehensive analysis of <br />rainfall/runoff data collected in and near the Urban Drainage and Flood <br />Control District. These two chapters significantly revise the hydrology <br />analysis procedures for the Denver metropolitan area. The revisions are <br />based on a locally collected hydrologic data base over a 10-year period. <br />As a result, the revised methodology can be considered to be "regionally <br />calibrated" and state-of-the-art as we currently understand it. It is <br />our hope that you find it usefull and that it will provide more accurate <br />and more consistent urban runoff calculations for the Denver <br />metropolitan area. <br /> <br />Item 3 represents a correction needed to further limit the amount <br />of "street flow" during the major storm events. It is hoped that this <br />revision will improve the safety to public and reduce damages during the <br />large rainfall events. <br /> <br />Item 4 provides for a safety factor in the design of riprap channel <br />linings. The earlier revision to of the riprap section was, in_part, <br />based on studies by C.D.Smith in Canada. However, after reexamining <br />his publications, we concluded that C.D. Smith's equations were based on <br />