Difference between revisions of "Inlets"
Jenny Hill (talk | contribs) m |
|||
(13 intermediate revisions by one other user not shown) | |||
Line 1: | Line 1: | ||
+ | Concentrated flow inlets are associated with LID practices such as [[Bioretention]], [[Stormwater planters]], [[Infiltration trenches]] and [[infiltration chambers|chambers]]. | ||
+ | Sheet flow alternatives include [[level spreaders]], [[gravel diaphragms]] and [[vegetated filter strips]]. | ||
+ | Practices such as [[permeable paving]] and [[green roofs]] receive precipitation directly, whilst [[exfiltration trenches]] are connected directly to conventional storm sewers. | ||
+ | |||
Inlets for BMPs in the right of way should be located: | Inlets for BMPs in the right of way should be located: | ||
*At all sag points in the gutter grade | *At all sag points in the gutter grade | ||
*Immediately upgrade of median breaks, crosswalks, and street intersections. | *Immediately upgrade of median breaks, crosswalks, and street intersections. | ||
− | + | It is good practice to have several inlets sized to split higher flow between a number of smaller BMPs or along the length of a linear pratice ([[Overflow|Offline overflow]]). | |
{| class="wikitable" | {| class="wikitable" | ||
Line 18: | Line 22: | ||
*Drains may be configured either perpendicular or parallel to the flow direction of the roadway, collecting runoff and directing to a single inlet in the BMP. | *Drains may be configured either perpendicular or parallel to the flow direction of the roadway, collecting runoff and directing to a single inlet in the BMP. | ||
| | | | ||
− | *Inlet aprons or depressions increase inflow effectiveness of | + | *Inlet aprons or depressions increase inflow effectiveness of curb cuts. |
*Steeply angled aprons can be hazardous, especially to people bicycling. Curbside and protected bike lanes along concrete aprons should be at least 1.8 m to give cyclists adequate clear width from the curb and any pavement seams. Aprons can also be marked visually to indicate their perimeter. | *Steeply angled aprons can be hazardous, especially to people bicycling. Curbside and protected bike lanes along concrete aprons should be at least 1.8 m to give cyclists adequate clear width from the curb and any pavement seams. Aprons can also be marked visually to indicate their perimeter. | ||
*For aprons into [[bioretention]], the curb may angle into the cell to improve conveyance of gutter flow into the facility. Aprons typically drop 50 mm into the bioretention cell, with another 50 mm drop behind the curb to maintain inflow as debris collects. | *For aprons into [[bioretention]], the curb may angle into the cell to improve conveyance of gutter flow into the facility. Aprons typically drop 50 mm into the bioretention cell, with another 50 mm drop behind the curb to maintain inflow as debris collects. | ||
Line 26: | Line 30: | ||
*An inlet sump is recommended to settle and separate sediment from runoff where a large amount of debris is expected. | *An inlet sump is recommended to settle and separate sediment from runoff where a large amount of debris is expected. | ||
*Water drains into a catch basin, where debris settles in its sump. After [[pretreatment]], water drains via a pipe or opening into the BMP. | *Water drains into a catch basin, where debris settles in its sump. After [[pretreatment]], water drains via a pipe or opening into the BMP. | ||
− | *The sump can be directly connected to a perforated [[underdrain]] pipe to distribute the flow to the [[bioretention]] or | + | *The sump can be directly connected to a perforated [[underdrain]] pipe to distribute the flow to the [[bioretention]], supported [[soil cells]] or underground practices such a [[trenches]] or [[chambers]] . |
*Sump inlets should not be sited where pedestrians will have to negotiate with them. | *Sump inlets should not be sited where pedestrians will have to negotiate with them. | ||
| | | | ||
Line 33: | Line 37: | ||
*This style of inlet can be combined with a curb cut, to maintain capacity in case debris clogs the grate. | *This style of inlet can be combined with a curb cut, to maintain capacity in case debris clogs the grate. | ||
|- | |- | ||
− | | | + | |style="vertical-align: top;"|{{:Trench drains: Gallery}} |
− | |{{:Curb cuts: Gallery}} | + | |style="vertical-align: top;"|{{:Curb cuts: Gallery}} |
− | | | + | |style="vertical-align: top;"|{{:Inlet sumps: Gallery}} |
− | | | + | |style="vertical-align: top;"|{{:Depressed drains: Gallery}} |
|} | |} | ||
==External links== | ==External links== | ||
https://nacto.org/publication/urban-street-stormwater-guide/stormwater-elements/bioretention-design-considerations/inlet-design/ | https://nacto.org/publication/urban-street-stormwater-guide/stormwater-elements/bioretention-design-considerations/inlet-design/ |
Revision as of 19:34, 25 October 2018
Concentrated flow inlets are associated with LID practices such as Bioretention, Stormwater planters, Infiltration trenches and chambers. Sheet flow alternatives include level spreaders, gravel diaphragms and vegetated filter strips. Practices such as permeable paving and green roofs receive precipitation directly, whilst exfiltration trenches are connected directly to conventional storm sewers.
Inlets for BMPs in the right of way should be located:
- At all sag points in the gutter grade
- Immediately upgrade of median breaks, crosswalks, and street intersections.
It is good practice to have several inlets sized to split higher flow between a number of smaller BMPs or along the length of a linear pratice (Offline overflow).
Trench drains | Curb cuts | Inlet sumps | Depressed drains |
---|---|---|---|
|
|
|
|
|
|
|
Depressed drains: Gallery |
External links[edit]
- ↑ Mullen, T.J. Prioritizing trash capture and clean oceans: Stormwater hoods and traps lead the way in effectiveness. The Municipal magazine. June 1, 2022. Accessed: https://www.themunicipal.com/2022/06/prioritizing-trash-capture-and-clean-oceans-stormwater-hoods-and-traps-lead-the-way-in-effectiveness/
- ↑ Erickson, A.J. and Hernick, M.A., 2019. Capture of Gross Solids and Sediment by Pretreatment Practices for Bioretention. Accessed: https://conservancy.umn.edu/handle/11299/201607
- ↑ Halvorson, Tighe & Bond Studio. n.d. Halvorson, Tighe & Bond Studio. Retrieved from: https://www.halvorsondesign.com/willard-street-drainage
- ↑ Philadelphia Water Department. n.d. Chapter 4 Stormwater Management Practice Guidance 4.1 Bioinfiltration/Bioretention. Retrieved from: https://water.phila.gov/development/stormwater-plan-review/manual/chapter-4/4-1-bioinfiltration-bioretention/
- ↑ National Association of City Transportation Officials (NACTO). 2017. Urban Street Stormwater Guide - Inlet Design. Retrieved from: https://nacto.org/publication/urban-street-stormwater-guide/stormwater-elements/bioretention-design-considerations/inlet-design/
- ↑ Philadelphia Water Department. 2020. Stormwater Management Guidance Manual: Version 3.2. Accessed from: https://www.pwdplanreview.org/upload/manual_pdfs/PWD-SMGM-v3.2-20201001.pdf