Volume 2-05, Chapter 3 - City of Wichita

More documents

Recommendations

Info

Section 3.1 - Stormwater Management Controls Overview Ability to provide Nutrient Treatment: This column indicates the capability of a structural control to remove nutrients (nitrogen and phosphorus) in runoff. Ability to provide Bacteria Removal: This column indicates the capability of a structural control to remove bacteria in runoff. Ability to accept Hotspot Runoff: The last column indicates the capability of a structural control to treat runoff from designated hotspots. Hotspots are land uses or activities which produce higher concentrations of trace metals, hydrocarbons, or other priority pollutants. Examples of hotspots might include: gas stations, convenience stores, marinas, public works storage areas, garbage transfer facilities, material storage sites, vehicle service and maintenance areas, commercial nurseries, vehicle washing/steam cleaning, industrial sites, industrial rooftops, and auto salvage or recycling facilities. A check mark indicates that the structural control may be used for a hotspot site; however, it may have specific design restrictions. Please see the specific design criteria for the structural control for more details. Please note that hotspot treatment must be tailored to the characteristics of the hotspot runoff pollutants to be removed. Designation of a control as suitable for accepting hotspot runoff does not necessarily mean it is the appropriate treatment facility for that particular hotspot condition. Such a designation simply indicates that the facility is commonly used for treatment of some types of hotspot runoff. For example, and oil-water separator is appropriate for runoff containing some types of floatable greases or oils, whereas a surface sand filter would not be suitable. Site Applicability The third category of the matrix provides an overview of the specific site conditions or criteria that must be met for a particular structural control to be suitable. In some cases, these values are recommended values or limits and can be exceeded or reduced with proper design or depending on specific circumstances. Please see the specific criteria section of the structural control for more details. Drainage Area: This column indicates the approximate minimum or maximum drainage area considered suitable for the structural control practice. If the drainage area present at a site is slightly greater than the maximum allowable drainage area for a practice, a variance would be required. Likewise, the minimum drainage areas indicated for ponds and wetlands should not be considered inflexible limits, and may be increased or decreased depending on water availability (baseflow or groundwater), the mechanisms employed to prevent outlet clogging, or design variations used to maintain a permanent pool (e.g., liners). Slope: This column identifies general slope restrictions for the specific structural control practice. Minimum Head: This column provides an estimate of the minimum site elevation difference needed from the inflow to the outflow to allow for gravity operation within the structural control. Water Table: This column indicates water table or groundwater separation requirements for certain controls. Page 3 - 8 Volume 2, Technical Guidance
Section 3.1 - Stormwater Management Controls Overview Implementation Considerations The fourth category in the matrix provides additional considerations for the applicability of each structural control option. Residential Subdivision Use: This column identifies whether or not a structural control is suitable for typical residential subdivision development (not including high-density or ultraurban areas). Ultra-Urban: This column identifies those structural controls appropriate for use in very highdensity (ultra-urban) areas, or areas where space is a premium. Relative Capital Cost: The structural controls are ranked according to their relative construction cost per impervious acre treated, as determined from cost surveys. Maintenance Burden: This column assesses the relative maintenance effort needed for a structural stormwater control, in terms of three criteria: frequency of scheduled maintenance, chronic maintenance problems (such as clogging), and reported failure rates. It should be noted that all structural controls require routine inspection and maintenance. Step 2 - Specific Criteria The last three categories in the screening matrix, shown in Appendix E, Table E-2, provide an overview of various specific design criteria and specifications, or exclusions for a structural control that may be present due to a site’s general physiographic character, soils, or location in a watershed with special water resources considerations. Physiographic Factors Three key factors to consider are low-relief, high-relief, and karst terrain. Low relief (very flat) areas are common throughout Sedgwick County. High relief (steep and hilly) areas are rare but do exist in limited lot-scale areas. Karst areas (due to dissolution of salt beds) are limited to the northwest part of Sedgwick County. Special geotechnical testing requirements may be needed in karst areas. • Low relief areas need special consideration because structural controls require a hydraulic head to move stormwater runoff through the facility. • High relief may limit the use of some structural controls that need flat or gently sloping areas to settle out sediment or to reduce velocities. In other cases, high relief may impact dam heights to the point that a structural control becomes infeasible. • Karst terrain can limit the use of some structural controls as the infiltration of polluted waters directly into underground streams found in karst areas may be prohibited. In addition, ponding areas may not reliably hold water in karst areas. Volume 2, Technical Guidance Page 3 - 9
Page 1 and 2: CHAPTER 3 STORMWATER CONTROLS TABLE
Page 3 and 4: Chapter 3 - Table of Contents 3.2.8
Page 5 and 6: Chapter 3 - Table of Contents LIST
Page 7 and 8: Section 3.1 - Stormwater Management
Page 13: Section 3.1 - Stormwater Management
Page 31 and 32: Section 3.2.1 - Stormwater Pond 3.2
Page 33 and 34: Section 3.2.1 - Stormwater Pond Fig
Page 35 and 36: Section 3.2.1 - Stormwater Pond For
Page 37 and 38: Section 3.2.1 - Stormwater Pond •
Page 39 and 40: Section 3.2.1 - Stormwater Pond 1'
Page 45 and 46: Section 3.2.1 - Stormwater Pond 3.2
Page 47 and 48: Section 3.2.1 - Stormwater Pond Ste
Page 53 and 54: Section 3.2.2 - Extended Dry Detent
Page 59 and 60: Section 3.2.3 - Vegetative Filter S
Page 65 and 66:
Section 3.2.3 - Vegetative Filter S
Page 67 and 68:
Section 3.2.4 - Grassed Channel 3.2
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Section 3.2.4 - Grassed Channel max
Page 75 and 76:
Section 3.2.5 - Enhanced Swale 3.2.
Page 77 and 78:
Section 3.2.5 - Enhanced Swale Chan
Page 79 and 80:
Section 3.2.5 - Enhanced Swale B. G
Page 81 and 82:
Section 3.2.5 - Enhanced Swale High
Page 83 and 84:
Section 3.2.5 - Enhanced Swale Side
Page 85 and 86:
Section 3.2.5 - Enhanced Swale 3.2.
Page 87 and 88:
Section 3.2.6 - Infiltration Trench
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Section 3.2.7 - Soakage Trench 3.2.
Page 101 and 102:
Section 3.2.7 - Soakage Trench •
Page 103 and 104:
Section 3.2.8 - Surface Sand Filter
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Section 3.2.9 - Bioretention Areas
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Section 3.2.10 - Stormwater Wetland
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Section 3.3 - Secondary TSS Treatme
Page 153 and 154:
Section 3.3.1 - Proprietary Treatme
Page 155 and 156:
Section 3.3.1 - Proprietary Treatme
Page 157 and 158:
Section 3.3.2 - Gravity (Oil-Water)
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
Section 3.3.3 - Alum Treatment 3.3.
Page 165 and 166:
Section 3.3.3 - Alum Treatment •
Page 167 and 168:
Section 3.3.4 - Underground Sand Fi
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Section 3.3.5 - Organic Filter 3.3.
Page 183 and 184:
Section 3.3.5 - Organic Filter •
Page 185 and 186:
Section 3.4 - Other Stormwater Mana
Page 187 and 188:
Section 3.4.1 - Conventional Dry De
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Section 3.4.2 - Underground Dry Det
Page 195 and 196:
Page 197 and 198:
Page 199 and 200:
Section 3.4.3 - Porous Pavement 3.4
Page 201 and 202:
Section 3.4.3 - Porous Pavement The
Page 203 and 204:
Section 3.4.3 - Porous Pavement com
Page 205 and 206:
Section 3.4.3 - Porous Pavement Fig
Page 207 and 208:
Section 3.4.4 - Modular Porous Pave
Page 209 and 210:
Page 211 and 212:
Page 213 and 214:
Section 3.4.5 - Green Roof 3.4.5 Gr
Page 215 and 216:
Section 3.4.5 - Green Roof Signific
Page 217 and 218:
Section 3.4.5 - Green Roof 3.4.5.3
show all

Volume 2-05, Chapter 3 - City of Wichita

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?