Responses to comments
Thank you to all of our active community members below, for helping us to make corrections and find additional useful content
12 April 2019 It looks like there is a unit conversion error in the equation: ST=RVCT×Ac×C×0.1. When I do a unit conversion from mm.ha to m3, I find that the conversion factor should be 10, not 0.1.
- You are quite right, thank you. This has now been corrected on the page Bioretention: Sizing.
7 Feb 2019 There is no "L" in the equation. Perhaps a second equation for a pipe orifice would help clarify that.
- There were a few typos in the orifice equation, it has been reviewed and we believe that they have all been corrected. That page also has a link to the adapted variation for perforated pipe flow.
20 November 2018
What if different calculation pages were part of the table of contents? So the section could be titled "Calculations" and within that link could be different pages of calculations instructions from area and volume calculations to gradient slope calculations. Also I think the table of contents should be available on the left margin especially when a user is browsing through the wiki site and would like to read another section of the wiki.
- Thanks Hilary, a category tag of Calculations has been created to help screen for these types of resources. The table of contents is now available on the left menu bar.
20 November 2018
What a great site and resource you have created. It’s a pleasure to be part of it.
- Thanks Jeff
4 November 2018
While navigating the wiki, I have come across a number of references to using excess water for irrigationHuman application of water to agricultural or recreational land for watering purposes. City of Toronto Wet Weather Flow Management November 2006 47 on green roofs or rain barrels. However, it may be useful to include information on 'Keyline Design,' first developed by P. A. Yeomans in the 1950's. While geared towards agricultural and pastoral improvement, it has applications in most water management systems.
- Excellent reference, thank you Alex. I shall create a page explaining these Keyline design principles, some of which I believe are similar to 'micro-grading'.
31 August 2018
Take a look a this address : https://stormwater.extension.oregonstate.edu/standard-details There's plenty interesting plans with notes to see how to make important changes to the plans following the field reality!
- GreenGirl subscribes to the same share-and-share alike Creative Commons licensing as we do. We have her website and a few similar resources linked on our Drawings page.
25 July 2018
Do the units check out for calculating the total depth of the stone reservoirAn underlying bed filled with aggregate or other void-forming fill material that temporarily stores stormwater before infiltrating into the native soil or being conveyed by an underdrain pipe.? (i.e. should f' be in units of m/hr instead of m/day?)
- The notation used in the equations on Permeable paving: Sizing is being brought into line with the other sections of the site. Units have also been checked and brought into line to millimeters and hours as used for the other BMPs.
16 July 2018
I think Table 1 in this article (http://pubs.rsc.org/ru/content/articlehtml/2018/ew/c7ew00511c) would be good for the wiki guide - it explains the traits of vegetation and how they impact hydrology or water quality.
- Thanks Sylvie, the information from within that article has been used to produce a similar table on the Plants page.
11 June 2018
The term "forebayA pretreatment basin at the inlet of a practice that allow settling out of sediment and associated contaminants suspended in urban runoff." has a strong industry connection to SWMStormwater Management ponds, should this page have a different/more specific name?
- Thanks Alana and Steve, "ForebayA pretreatment basin at the inlet of a practice that allow settling out of sediment and associated contaminants suspended in urban runoff." now redirects to the newly named Pretreatment features page as you suggest.
24 April 2018
A general feedback from a french user - I do not know the meaning of the acronym LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting., used profusely in this article, making it hard to understand. I think it would be very helpful to have a definition for all the acronyms by hovering the mouse cursor over them, just like you did in the sixth paragraph of "Targeting hard surfaces" with the definition of "Rainwater harvestingThe practice of intercepting, conveying and storing rainwater for future use. Captured rainwater is typically used for outdoor non-potable water uses such as irrigation, or in the building to flush toilets.". This type of definition should be available for all the acronyms used in every other pages of this wiki, at least once per acronym per page.
- 'LIDLow Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.' has been added to the terms using the same definition for 'Low Impact DevelopmentLow impact development is a stormwater management and land development strategy applied at the parcel and subdivision scale that emphasizes conservation and use of on-site natural features integrated with engineered, small scale hydrologic controls to more closely mimic pre-development hydrologic functions.A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.'. We will continue to look for missing information of this type.
10 April 2018
Do you have any specs for designing berms around a bioretentionA shallow excavated surface depression containing prepared filter media, mulch, and planted with selected vegetation. pondA body of water smaller than a lake, often artificially formed.?
- Please see Berms
23 March 2018
Is it possible to get the the planting list updated to include native species?
- Certainly! This information will be added as we review the plant tables in summer 2018.
21 March 2018
Is there a reliable set of estimated design infiltration rates for sites where only soil type is currently known? Additional tests will be conducted, but for now we are looking for numbers to begin an estimate, and a reasonable basis for those numbers.
- The curators of Minnesota's stormwater wiki have conducted a very thorough literature review to establish their suggested values for design infiltration rates. The lowest value on their table for clayey soils is 15 mm/hr, we believe that this is a reasonable estimate for clay1. A mineral soil separate consisting of particles less than 0.002 millimeter in equivalent diameter. 2. A soil texture class. 3. (Engineering) A fine-grained soil (more than 50 percent passing the No. 200 Sieve) that has a high plasticity index in relation to the liquid limit. (Unified Soil Classification System). soils. Designers may wish to add a safety correction to this number before undertaking their design calculations.
- Minnesota Stormwater Manual contributors, "Design infiltration rates," Minnesota Stormwater Manual, , https://stormwater.pca.state.mn.us/index.php?title=Design_infiltration_rates&oldid=37031 (accessed May 11, 2018).