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<br />. All segments <br /> <br />Taylor Bayou AI04 <br />. All segments <br /> <br />The listed watersheds are shown on Figure 3. <br /> <br />5.5.1 Design Standards for Detention Basins <br /> <br />Detention requirements for developments less than 50 acres shall be according to the following table. For <br />developed areas of 10 acres or less, the required volume equals the total development area times the <br />appropriate storage coefficient. For areas greater than 10 acres and less than 50 acres the volume is <br />determined by applying Harris County Flood Control District criteria for small watersheds. <br /> <br />Table 2 (Also, See Figure 4) <br /> <br />Developed Area <br />() to I acres <br />1 to 10 acres <br />10 to 50 acres <br /> <br />Storage Coefficient <br />0.20 acre ft. / acre <br />0.45 acre 1'1. / acre <br />per HCFCD criteria <br /> <br />For developments which are larger than 50 acres, Harris county Flood Control District and/or the City <br />Engineer shall approve the detention facility criteria <br /> <br />5.5.2 Outlet Sizing <br /> <br />1. The outlet structure shall be designed using the orifice equation as follows' <br /> <br />Q = CA x (2gh)V, <br /> <br />Where. <br />C=O.8 <br />A = cross sectional area <br />g = 32.2 feet / sec^2 <br />h = head differential <br /> <br />For head differential use 2' or the 100-year water surface in pond minus the 25-year <br />water surface in receiving channel, if available. <br /> <br />2. Minimum restrict or shall be 6" diameter. <br /> <br />5.5.3 Generally accepted areas of localized runofIto roadways and the ditches adjacent to them consists of <br />150-ft wide strips adjacent to the roadway right-of-way on each side of the road. Drainage from beyond <br />this commonly accepted width zone is discouraged and should be directed to areas and/or drainage <br />pathways to which natural drainage occurs. If such drainage cannot be safely directed to natural drainage <br />pathways, on-site detention shall be required at a rate prescribed in this chapter to limit the peak rates of <br />discharge to an acceptable level for discharge either to the roadway or natural drainage paths. Such event is <br />prescribed by the design capacity of said receiving outfall. <br /> <br />5.5.3 Additional Standards for Detention Basins <br /> <br />nle detention facility shall be designed for easy maintenance. For smaBer developments the designer is <br />encouraged to use parking lots, underground piping, swales, green spaces, etc. to achieve the volume <br />required. <br /> <br />l>'tormwater Criteria Page 5 of 10 <br />