nyuuzyou/wikis huggingface dataset:
Biochar

==What Is It?==
Biochar is a carbon-rich material produced by pyrolysis of organic feedstocks such as municipal, agricultural, and forestry wastes. It has a high surface area, which enhances soil aggregation, water holding capacity, and organic carbon content. However, biochar properties and effectiveness for pollutant sorption depends on feedstock and pyrolysis conditions. Iqbal H, Garcia-Perez M, Flury M. Effect of biochar on leaching of organic carbon, nitrogen, and phosphorus from compost in bioretention systems. Science of the Total Environment. 2015;521-522: 37-45. doi: 10.1016/j.scitotenv.2015.03.060
==How is it being used?==
No evidence was found of biochar being used for LID projects in Ontario yet. 
*If you have used biochar in LID design, please let us know.
==Benefits==
One study states that the mixing of biochar with compost did not decrease the phosphorus leaching from the mixture. Based on this study, it would seem that biochar is ineffective for phosphorus removal. However, some other papers indicate that biochar mixed with sand was able to retain some trace organic contaminants (TOrCs), Ulrich B, Im E, Werner D, Higgins C. Biochar and Activated Carbon for Enhanced Trace Organic Contaminant Retention in Stormwater Infiltration Systems. Environ. Sci. Technol. 2015;49:6222-6230. doi: 10.1021/acs.est.5b00376. and that after six months of operation, biochar-amended biofilters improved removal of total dissolved phosphorus and other TOrCs by greater than 60%. Ulrich B, Loehnert M, Higgins C. Improved contaminant removal in vegetated stormwater biofilters amended with biochar. Environ. Sci.: Water Res. Technol.,2017;3:726-734. doi: 10.1039/C7EW00070G Amendment of LID systems with biochar has shown promise for improved removal of heavy metals, bacteria, nutrients, and TOrCs. Ulrich B, Vignola M, Edgehouse K, Werner D, Higgins C. Organic Carbon Amendments for Enhanced Biological Attenuation of Trace Organic Contaminants in Biochar-Amended Stormwater Biofilters. Environ. Sci. Technol. 2017;51:9184-9193. doi: 10.1021/acs.est.7b01164.
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category: materials
category: phosphorus
category: water quality
Bioretention: Construction checklist

Common construction pitfalls can be avoided with careful construction supervision that focuses on the following aspects:
Erosion and Sediment Control 	Erosion and Sediment Control
  	Bioretention locations should be blocked from construction traffic and should not be used for erosion and sediment control
 	Proper erosion and sediment controls should be in place for the drainage area
Materials 	Materials
  	Gravel for the underdrain should be clean and washed; no fines should be present in the material
 	Underdrain pipe material should be perforated and of the correct size (when specified in design)
 	A cap should be placed on the upstream (but not the downstream) end of the underdrain (when specified in design)
 	Biomedia should be tested to confirm that it meets specifications
 	Mulch composition should be correct
Elevations 	Elevations
  	Depth of the gravel and invert of the underdrain
 	Inverts for inflow and outflow points
 	Filter media depth
 	Ponding depth provided between the surface of the filter bed and the overflow structure
 	Mulch depth
Landscaping and Stabilization 	Landscaping and Stabilization
  	Correct vegetation should be planted
 	Pretreatment area should be stabilized
 	Drainage area should be stabilized prior to directing water to the bioretention
The following items should be checked after the first rainfall event, and adjustments should be made as necessary:	The following items should be checked after the first rainfall event, and adjustments should be made as necessary:
  	Outfall protection/energy dissipation at concentrated inflow should be stable
 	Flow should not concentrate and should spread evenly over the filter bed
 	Ponded water at the surface of the bioretenton facility must drain within 24 hours of the end of the storm event. The biomedia should fully drain within a maximum period of 72 hours
 	Excessive sediment accumulation should not be present
category:Checklists
category:Construction
Bioretention: Internal water storage

An internal water storage (IWS) reservoir or zone is created by including an upturned 90 deg on the outflow pipe to force an elevated outlet. For practical reasons, this is commonly applied within a manhole or other nearby piece of infrastructure, rather than being buried directly adjacent. The effect is to create longer term, water-logged, low-oxygen environment within the bottom of the bioretention cell. 
This has two primary benefits:
Additional infiltration is promoted by holding the water in place over the native soil for longer, 
The types of microbes that grow in a low-oxygen environment are also better at completing the removal of nitrogen compounds from the water. This effect is enhanced by using a low-nutrient carbon source in the bioretention filter media and storage reservoir aggregate.
 
Saturated soil conditions can kill plants in the bioretention cell, so a minimum of 30 cm vadose zone (free draining depth) must be included for healthy rooting at the top of the cellBrown RA, Hunt WF, Kennedy SG. Designing Bioretention with an Internal Water Storage (IWS) Layer.; 2011.. 
Nitrogen removal rates are linked to increased depth of IWS, so that a minimum of 45 cm of IWS is recommended where the depth of the native soils and bioretention cell permitLynn TJ, Yeh DH, Ergas SJ. Performance of Denitrifying Stormwater Biofilters Under Intermittent Conditions. Environ Eng Sci. 2015;32(9):150710132840004. doi:10.1089/ees.2015.0135.. 
However, any depth of IWS would be expected to make some improvement on water retention and infiltration. 
==References==
Bioretention: Sizing and modeling

This article describes recommended design approaches when available space for the practice is constrained.
Before beginning the sizing calculations certain parameters must be known or estimated. See Bioretention: Sizing for parameter descriptions and conceptual diagram illustrating key components of bioretention practices. Note that some of these parameters are limited:
#The maximum total depth will be limited by construction practices i.e. not usually > 2 m.
#The maximum total depth may be limited by the conditions underground e.g. the groundwater or underlying geology/infrastructure.
#The minimum total depth will be limited by the need to support vegetation (e.g not less than 0.6 m to support deep rooting perennials and shrubs).
#Bioretention has a maximum recommended catchment impervious area to practice permeable (footprint) area ratio, R (or I/P ratio) of 20.
==Size a bioretention cell receiving flows directly to the storage reservoir for a constrained depth==
If there is a constraint to the depth (dT) of the practice, calculate the required storage reservoir footprint area (Ar), as:
A_{r}=\frac{i\times D\times A_i}{(d_{r}\times n')+(f'\times D)}
If R is greater than 20, consider decreasing catchment impervious area (Ai) by draining less area to the practice.
==Size a bioretention cell where drainage area and practice area are fixed==
If the land area is limited, determine the I/P ratio, which is the ratio of catchment impervious area (Ai) to practice pervious footprint area (Ap):
:R=\frac{A_{i}}{A_{p}}
Then calculate the required storage reservoir depth (dr), as:
d_{r}=\frac{D \left[ (R\times i)-f'\right]}{n'}
These equations assume that infiltration occurs primarily through the base of the facility. 
This spreadsheet tool has been set up to perform all of the infiltration practice sizing calculations shown above.
==Calculate drawdown time==
In some situations, it may be possible to reduce the size of the bioretention required, by accounting for rapid drainage. Typically, this is only worth exploring over sandy soils with rapid infiltration. 
Note that narrow, linear bioretention features drain faster than round or blocky footprint geometries. 
*Begin the drainage time calculation by dividing the storage reservoir area of the practice (Ar) by the perimeter (x).
*Use the following equation to estimate the time (t) to fully drain the facility: 
:t=\frac{nA_{r}}{f'x}ln\left [ \frac{\left (d_{r}+ \frac{A_{r}}{x} \right )}{\left(\frac{A_{r}}{x}\right)}\right]
This 3 dimensional equation makes use of the hydraulic radius (Ar/x), where x is the perimeter (m) of the facility. 
Maximizing the perimeter of the facility directs designers towards longer, linear shapes such as bioswales. 
category: modeling
category: infiltration
Bioretention: Streetscapes

Image:Curb extension.png|thumb|700 px|This is an image map of a curb extension, clicking on components will load the appropriate article.
rect 545 37 609 54 Curb cuts
rect 286 583 353 599 Curb cuts
rect 544 56 606 114 Forebays
rect 366 579 282 529 Forebays
poly 378 571 486 571 602 577 599 130 504 124 493 206 390 209 371 362 Perennials: List
poly 459 1110 363 1111 366 1030 594 1025 599 1109 496 1110 497 1092 465 1093 Perennials: List 
poly 285 469 362 472 354 335 375 203 478 191 492 74 393 109 334 159 297 224 285 291 Graminoids: List
rect 287 1040 353 1114 Graminoids: List
rect 279 1114 470 1142 Mulch
rect 492 1115 600 1141 Mulch
rect 282 1145 468 1217 Bioretention: Filter media
rect 491 1147 603 1217 Bioretention: Filter media
rect 282 1219 467 1248 Choking layer
rect 491 1217 600 1244 Choking layer
rect 282 1250 469 1299 Reservoir gravel
rect 491 1250 602 1299 Reservoir gravel
poly 3 1325 471 1322 474 1292 474 1096 487 1095 487 1339 3 1340 Overflow
Hydraulically separated or connected with an underdrain, these are often quite small units of 5 - 50 m2 each. In urban settings the bioretention may be bounded entirely with hardscape, restricting options for pretreatment and sheet flow. Amenity and safety can be enhanced on sidewalks with a short (~ 45 cm wall) for seating, although the finished grade is usually only slightly lower than surroundings. Where underground space permits, shade trees are common feature of these facilities, enhancing the streetscape experience and optimizing transpiration. This type of bioretention is often designed offline, with bypass overflow. 
An excellent opportunity for integrating more bioretention into the street is through careful design of curb extensions for traffic control. See Roadside safety for design advice specific to this application. 
==Gallery==
==See Also==
*Bioretention
*Stormwater planters
*Stormwater tree trenches
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Bioretention: TTT

Surface 	Surface
Berm height (mm) 	Ponding depth, maximum (e.g. 300 mm), sometimes referred to as 'bowl depth'
Surface roughness (Manning’s n) 	Lower numbers indicate less surface obstruction and result in faster flow
Suggested ranges:
* Mown grass (dependent on density) 0.03 – 0.06 Oregon State Univ., Corvallis. Dept. of Civil, Construction and Environmental Engineering.; Environmental Protection Agency, Cincinnati ONRMRL. Storm Water Management Model Reference Manual Volume I Hydrology (Revised). 2016:233. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100NYRA.txt Accessed August 23, 2017.
* Stone 0.03 – 0.05
* Planted (highly dependent on density) 0.05 – 0.15
Surface slope (%) 	If the slope > 3% a series of Check dams or weirs should be included in the design.
Soil (bioretention filter media) 	Soil (bioretention filter media)
Thickness (mm) 	Depth of filter media
Porosity of filter media 	Suggest 0.35 unless otherwise tested
Field capacity (fraction) 	Suggested range 0.10 - 0.12
Wilting point (fraction) 	Suggested value 0.03
Hydraulic conductivity (mm/hr) 	Suggested range 25 – 250 mm/hr
Conductivity slope 	Suggested value 45
Suction head (mm) 	Suggested range 50 - 60
Storage 	Storage
Thickness (mm) 	Depth of storage aggregates layer
Porosity of storage reservoir aggregate	Suggest value 0.4 unless otherwise tested
Seepage rate (mm/hr) 	Infiltration rate of native soil
Clogging factor 	Maybe up to 0.5 to account for some anticipated maturation.
Design drainage time (hrs) 	Maximum permissible time to fully drain the storage reservoir.
Drain (underdrain) 	Drain (underdrain)
Flow coefficient 	Suggested value 1
Flow exponent 	Suggested value 1
Offset height 	This is the height from the base of the cell to the height at which the drain discharges. In some designs this may be the height of the perforated pipe within the storage layer; in others this height is adjusted by creating an upturn in the discharge pipe.Bioretention: Partial infiltration
category: modeling
Bioretention: Variations

__NoTOC__
 Types of bioretention by underground design
Type 	Gravel layer	Underdrain	Liner	Mechanisms 	Schematic
Rain gardens 	- 	- 	- 	These are the simplest construction, often used by residents or community groups. Volume reduction is through infiltration and evapotranspiration. 	
Infiltrating bioretention 	yes 	- 	- 	This is a highly desirable type of bioretention where the soils permit infiltration at a great enough rate to empty the facility between storm events. Volume reduction is primarily through infiltration to the underlying soils, with some evapotranspiration. As there is no outflow from this BMP, it is particularly useful in areas where nutrient management is a concern to the watershed. 	
Partially infiltrating bioretention	yes 	yes 	- 	Including an underdrain in the gravel storage layer help to empty the facility between storm events, even over ‘tight soils’. The drain discharges to a downstream point, which could be an underground infiltration facility. Limited volume reduction is gained through infiltration and evapotranspiration. By raising the outlet of the discharge pipe the bottom portion of the BMP can only drain through infiltration. This creates a fluctuating anaerobic/aerobic environment which promotes denitrification. Increasing the period of storage has benefits for promoting infiltration, but also improves water quality for catchments impacted with nitrates. A complimentary technique is to use fresh wood mulch, which also fosters denitrifying biological processes.	
Biofilters(non-infiltrating) 	yes 	yes 	yes 	This type may be required over contamination hot-spots or in very dense urban areas with a lot of other underground infrastructure. The design includes an impermeable base and sides, so that volume reduction is made only through evapotranspiration. This type of cell can be constructed above grade in any waterproof and structurally sound container, e.g. in cast concrete or a metal tank.
Bioretention cells: Gallery

IMG 2457 750X500.jpg| Parking lot bioretention with surface ponding well in foreground, Kortright Centre, Vaughan, ON. Read about the performance of this practice in the technical brief.
Edwards Gardens Bio 2014.JPG| Parking lot bioretention sharing underground reservoir with adjacent permeable paving, Edwards Gardens, Toronto, ON. Read a case study about it here.
ER Bioretention.jpg| Parking lot bioretention with decorative stone for erosion control, and perforated pipe access standpipe in foreground, Earth Rangers Centre, Vaughan, ON. Read about the performance of this practice in the technical brief.
7sigma RainGarden64.JPG|The sunken curb holds the edge of the asphalt pavement and lets water freely flow to the bioretention cell beside the 7sigma parking lot in Minneapolis, MN (USA)Photo credit:Brian Ash
File:Mississauga Elm Dr bioswale_001.jpg| Bioretention cells on Elm Drive, Mississauga, ON, with vertical sides and hardscape perimeter receive road runoff via leader pipes from road catch basin inlets. Read about the stormwater system at this site in the performance assessment report.
Lakeside - sheet flow parking lot 1.JPG| The grade and lack of curb allow for sheet-flow runoff into this bioretention facility. Lakeside Park, Mississauga, ON
File:HD urban bioretention_1.jpg| Bioretention cell receiving road and walkway runoff in a high density development setting. 
File:Ultra urban bioret bump out 2.jpg|300px|Bioretention bump out in a dense urban setting receiving runoff via side inlet catch basin and curb openings on the walkway side of the installation.
File:Fairford park toronto.jpg|Fairford Parkette featuring a bioretention cell retrofitted into a roadway in downtown Toronto, ON. Read a case study about it here.
File:Ajax Waterfront Park bioret 1.jpg|Bioretention cell located in Waterfront Park in Ajax, ON.
File:Mississauga IMAX parking bioret 1.JPG|Parking lot bioretention cell at IMAX corporate headquarters in Mississauga, ON. Read about the IMAX stormwater system in the performance assessment report
File:Bump-out bioretention 2.jpg|A curb extension bioretention cell in action during a major rain event. 
File:Brampton Wychwood bioret 2015 1.jpg|Bioretention cell receiving road runoff in the Wychwood neighbourhood of Brampton, ON. The nearby catch basin conveys overflows during major rain events. Read about the stormwater system in this community in the performance assessment report.
File:Kortright parking lot bioret 3.jpg|Kortright Centre parking lot bioretention cell in action during a rain event, Vaughan, ON.
Category:Gallery
Bioretention media storage

Bioretention filter media may be assumed to have a filter media porosity of 0.4.
This has been calculated as the difference between the media porosity and field capacity from a number of studies. 
# Marine sand: 0.51 - 0.06 = 0.45 Liu, Ruifen, and Elizabeth Fassman-Beck. “Pore Structure and Unsaturated Hydraulic Conductivity of Engineered Media for Living Roofs and Bioretention Based on Water Retention Data.” Journal of Hydrologic Engineering 23, no. 3 (March 2018): 04017065. doi:10.1061/(ASCE)HE.1943-5584.0001621
# Marine sand with 10 % compost: 0.51 - 0.11 = 0.40 
# Marine sand with 20 % compost: 0.53 - 0.12 = 0.41 
# Marine sand with 20 % compost & 20 % topsoil: 0.52 - 0.16 = 0.36 
# Sand: 0.46 - 0.1 = 0.36 Saxton, K E, and W J Rawls. “Soil Water Characteristic Estimates by Texture and Organic Matter for Hydrologic Solutions.” Soil Science Society of America Journal, 2006. doi:10.2136/sssaj2005.0117. 
# NC sandy bioretention mix: 0.47 - 0.07 = 0.40 Davis, Allen P., Robert G. Traver, William F. Hunt, Ryan Lee, Robert A. Brown, and Jennifer M. Olszewski. “Hydrologic Performance of Bioretention Storm-Water Control Measures.” Journal of Hydrologic Engineering 17, no. 5 (May 2012): 604–14. doi:10.1061/(ASCE)HE.1943-5584.0000467.
# Bioretention soil I: 0.71 - 0.1 = 0.61 Li, Houng, and Allen P. Davis. “Urban Particle Capture in Bioretention Media. I: Laboratory and Field Studies.” Journal of Environmental Engineering 134, no. 6 (June 2008): 409–18. doi:10.1061/(ASCE)0733-9372(2008)134:6(409).
# Bioretention soil II: 0.52 - 0.1 = 0.42 
# M minus mean θini: 0.76 - 0.32 = 0.44 Roy-Poirier, A., Y. Filion, and P. Champagne. “An Event-Based Hydrologic Simulation Model for Bioretention Systems.” Water Science and Technology 72, no. 9 (November 11, 2015): 1524–33. doi:10.2166/wst.2015.368.:
==References==
:
Bioswales: Gallery

Bioswale Miss Rd.jpg| Note the use of stone in the centre of the channel, with mulch cover on the side slopes. Mississauga Road, ON
Rain Garden (14418205110).jpg|Bioswale in High Point neighborhood, Seattle, WA Photo credit: USEPA
Streetside swale Seattle.jpg|Streetside swale in Seattle
Infiltration Trench - Wychwood.JPG|This feature is a bioswale in that the underlying soil has been replaced with engineered filter media. The turf finish simplifies landscape maintenance. Brampton, ON
File:County Court Blvd biofilter 2016.jpg|A bioswale located on Country Court Blvd., located in Brampton, ON> Read more about the performance of this feature and associated rpoject, by reading the following Grey to Green Conference Presentation, 2018. Dean Young - STEP, 2018
File:Downsview Park bioswale 2018 1.jpg| Bioswale located in Downsview Park, Toronto ON. with Check dams.
File:Grass bioretention swale 1.jpg| Grassed bioswale with Vegetated filter strips
File:MEC Burlington LID parking 2015 1.jpg| Bioswale located in a parking lot with a 'beehive-styled' overflow, with Curb cuts Inlets at the back of the feature, located in the Burlington ON.
File:Peel Airport Rd bioswales 2020.jpg:Bioswale feature, with an inlet and Level spreader to allow water from the road enter the feature, while at the back of the feature there is a 'beehive-styled' overflow connected to conveyance pipes that allow excess water leave the feature during major rain events. Read more about the effectiveness of this feature and its performance in this tech brief here, Effectiveness of Retrofitted Roadside Biofilter Swales. STEP, 2018
File:Peel Mississauga Rd bioswale 2017.jpg|Stone-lined bioswale with rock check dams located to helps slow the flow of water as it enter the system from the nearby roads. [[ STEP, 2017
Category:Gallery
Bold & Gold

__NOTOC__
==What is it?==
Bold & Gold is a biosorption activated media (BAM) for pollution control developed by the Stormwater Management Academy at the University of Central Florida. It can be used to achieve nitrogen and phosphorus reduction in stormwater, wastewater and agricultural applications such as retention basins, swales and rain gardens, urban gardens and soil cells, permeable pavements, green roofs, filter strips and more. Bold & Gold is composed of a patented blend of mineral materials, sand, and clay.
==How is it being used?==
Bold & Gold Filtration Media is currently being used in experimental projects in North Carolina to evaluate nutrient reduction capabilities. No projects that used Bold & Gold were found in Ontario, however, it has been used for projects such as an upflow filter chamber following a detention pond, a commercial green roof in Florida, and a subsurface upflow wetland filter for nutrient removal. Stormwater Treatment Environments, LLC. Success Stories. http://greensmarts.com/success_stories.html. Accessed September 8, 2017. Filtration Media Specifications and Typical Cross Sections are provided on the Bold & Gold website.
==Benefits==
The results of a study by Hood, Chopra, and Wanielista provided promising results for the use of Bold & Gold for phosphorus removal. In field scale testing, Bold & Gold had a 71% removal efficiency of total phosphorus. This was compared to sandy soil which had many negative values, indicating significant leaching of total phosphorus from the sod. The average Soluble Reactive Phosphorus (phosphorus that is readily available to plants and algae) removal efficiency was 95%. Overall, the Bold & Gold system performed much better when compared to a sandy soil bio-filtration system. Hood A, Chopra M, Wanielista M. Assessment of Biosorption Activated Media under Roadside Swales for the Removal of Phosphorus from Stormwater. Water. 2013;5:53-66. doi: 10.3390/w5010053.
==External links==
category:materials
category:phosphorus
category:Water quality