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" " The second priority should be the Eastern Flow path. Phaaedconstruct1on of Altern...Uv..21nth......,.,t ls conceivabl... but the full benefit. of the IX. STRE~T IMPROVEMENT PLAN improvementa would not be realized until the entire project ~as completed. Staged conotructlon in the &astern Plow Path would begin at the a19' '!'hompeon Riv<lr and ,."",k upstr..am t.o the unto" PaetHc Railroad pond. While the major benefits of the ....stern improvements would not be realired until the last phase of construction, starting at the south end of the route would merely transfer that area's flooding problem to a little further north until the projeot w..s completed through to thealg rhompson River. The third priority is Lola Park Tributary Alternative A4. This would eliminate inundation of buildings within the present 100-year flood plain northof!:lmStr....t. Introduction The street improvement plan for Milliken develops grading and paving d..aigne for Milliken's street ay..tem. The majority of th.. town's streets are pres~ntly unpaved. Street design wae tied to the Milliken drainage etudy because properly designed streets are a critical part of an efficient drainag.. syst..... Guidelines for deoign c...e frO/ll "Drainag..and street Design Ma.nual for the Town of Milliken, Colorado." The Wast..rn Flow Path is the fourth priority. Proposed 1rnproV'lllents here would confine runoff to Quentine Avenue keeping adjacent homes safe from flooding. I I I , I , I De..ign The basic concept behind the street improvement plan was to design the streets to carry the l0-year return period discharge within curb height at ao close to existing grade as possible. ~ street fiow net was developed based on existing grades and a typical residential street cross section (35-foot pavement width plus curb and gutter). The flow net indicated flow direction and street capacity. pellkrunoffratefrOll\eachcityb10ckforthel0-year atorm was estimated by the rational method and diapers..d into the streete along with incoming atorm water flows from the upland fields. This indicated which streets had inadequate capacity and whsre water would be concentrated. Grade changes _re .....de on a trial and error basis until the 10-ye~r di"chllrge could be routed throu9h to>Inon the streets. ~rom the finali=ed flow net (rigu~p 17) grll<!PR w~r.. Me~9..d with vertical pa~abolic curves of equal tangents. The preli~nary street designs tor e..cn of Milliken's streets are <leu,Ued in Plat.... 2 through 14. Plate 1 is the k"y to the loclltionof each detailed street design plate lInd gives ane><p1a nation of th.. symbols &nd abbreviations used. P1"te 15 shows cross sections of typi- csl collector and rssid..ntilll streets. Broad street was designed ae a oollec- terst.r"et. 11.11 other street", in to"", were designe<l a" r"e1d"ntia1 "treeta, althou~h Weld County should be contacted concerning the ",tatus cf Irene, QUentine, and Altce Av..nu.... prior to final design since th..y are county roads. Crosspana direct curb flows at intersections. They will be used as a ~eanS to more evenly distribute flow throughout the street system. ~dditiona1 drainage ..tructures will be necessary at points of concentration to route flow to points where it Cd" be convey..d out of town. ~ 36-incll corrug-"ted ....t.al culvert runs ,,,,,,thu,,d,,r Kig-hway60 froOl the "outheaat corner of t he Grace Avenue and Highway 60 intersection. North of the highway the culvert is