nyuuzyou/wikis huggingface dataset:
History and context

In 1993, the Ontario Ministry of the Environment (OMOE) and Ontario Ministry of Natural Resources (OMNR) released three policy documents focusing on integrating water resources management and urban planning:
* Water Management on a Watershed Basis: Implementing an Ecosystems Approach
* Subwatershed Planning
* Integrating Water Management Objectives into Municipal Planning Documents
These documents heralded a new approach to water management in Ontario. They emphasized the need for an increased focus on protecting the natural environment and the need for stormwater management practices to pay more attention to water quality and environmental concerns, in addition to addressing traditional water quantity concerns.
In 1994, the OMOE released two practitioners guides to stormwater management planning:
* Stormwater Quality Best Management Practices
* Stormwater Management Practices Planning and Design (SMPPD) Manual
The OMOE SMPPD manual was intended to introduce practitioners to a broad range of stormwater management facilities designed to not only offset the effects of hydrologic changes of urban development on streams and rivers, but also address water quality and erosion impacts. The SMPPD manual also provided detailed guidance on how to design and build multi-purpose facilities and included sections on operations and maintenance and environmental monitoring requirements.
In 2003, OMOE released a new Stormwater Management Planning and Design Manual, which significantly updated and expanded on the 1994 version. The 2003 manual:
* provided an overview of the impacts of urbanization on the hydrologic cycle and stream ecosystems
* addressed the evolution of the watershed planning process and its implications for the design process
* incorporated water quantity, erosion control, water quality protection, and water balance principles into the selection and design of stormwater management practices (SWMPs)
* documented the performance of monitored SWMPs
* incorporated design considerations for SWMPs in cold climates
* provided information on new “state of the art” SWMPs
* addressed infill projects
* updated operations and maintenance requirements
* provided design examples for SWMPs
* updated material related to planting strategies and the function of plant materials in SWMP design
* provided examples of retrofitting SWMPs
* outlined integrated planning for stormwater management
In 2010 LID specific design advice was collated by a team from Toronto Region Conservation Authority (TRCA) and Credit Valley Conservation (CVC). Information from both this 2010 guide, and the 2003 MOE manual has been reviewed and assimilated during the production of this website guide. 
Category:Background
Hooghoudt

===Spacing drainage pipes to reduce groundwater mounding===
In most LID underdrain applications, lateral drains should be spaced between 5 - 6 m apart. This recommendation is supported by an analysis of Hooghoudt's equation H.P.Ritzema, 1994, Subsurface flow to drains. Chapter 8 in: H.P.Ritzema (ed.), Drainage Principles and Applications, Publ. 16, pp. 236-304, International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. ISBN 90-70754-33-9W.H. van der Molen en J.Wesseling, 1991. A solution in closed form and a series solution to replace the tables for the thickness of the equivalent layer in Hooghoudt's drain spacing equation. Agricultural Water Management 19, pp.1-16van Beers, W.F.J. 1976, COMPUTING DRAIN SPACINGS: A generalized method with special reference to sensitivity analysis
and geo-hydrological investigations, International Institute for Land Reclamation and Improvement (ILRI) Wageningen, The Netherlands in relation to loamy or clayey native soils, where Kmedia>>Ksoil, finds the first term of the numerator negligible, so that the original equation:
Drain\ spacing=\sqrt{\frac{8K_{soil}H\left(D_{i}-D_{d}\right)\left(D_{d}-D_{w}\right)+4K_{soil}\left(D_{d}-D_{w}\right)^{2}}{q}}
may be simplified to:
Drain\ spacing=\sqrt{\frac{4K_{media}\left(D_{d}-D_{w}\right)^{2}}{q}}
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Hydrogeology hub

__NOTOC__
The Conservation Authorities Geoscience Group have prepared a guidance document which attempts to standardize the hydrogeological study requirements for development applications made to Conservation Authorities. It is a helpful guide for all low impact development applications which include infiltration. 
It is provided with the caveat that not all sections or content are necessary or appropriate for every case. Pre-consultation with your Conservation Authority and municipality is strongly recommended in all cases. 
Hydrogeological Assessment Submissions Conservation Authority Guidelines for Development Applications
==Infiltration==
The Ministry of the Environment are preparing advice on where and when to infiltrate rainwater and stormwater. 
Things to be mindful of are:
===Pollution hotspots===
===Karst===
==See also==
*Groundwater
*Infiltration
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Infiltration

Infiltration of stormwater into underlying native subgrade soils is one mechanism to achieving MECP runoff volume control targets. In many areas of Ontario, where municipal and private drinking water supplies are drawn from aquifers, it's also an important mechanism for groundwater recharge.
==Constraints==
Infiltration practices are not recommended:
#over-swelling clays or unstable subsoils,
#contaminated soils or sites with high risk of contamination from on-site activities (i.e. pollution hot spots),
#in areas of known or implied karst topography,
#on unstable or steep slopes (>15%),
# to treat construction site runoff,
#to treat combined sewer overflows, 
#in flood prone areas where the wastewater system is sensitive to groundwater conditions causing sewer backups,
#in areas where the ecology and natural hydrology are dependent upon surface water,
#in areas where increased infiltration will result in elevated groundwater levels that will damage critical utilities or private property, or
#where prohibitions and/or restrictions exist per approved source water protection plans (e.g. should not be used to treat pavement runoff within wellhead protection area B, 2 year time of travel zones, nor within groundwater quality issue contributing areas where Sodium or Chloride is a threat).
See Site considerations for further guidance on potential site constraints and LID facility type selection and design considerations. 
===Designing with constraints===
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category:Infiltration
Infiltration: TTT

Surface 	Surface
Berm height (mm) 	This is the height of the curb which constrains the overland sheet flow of water. Where curb cuts or other inlets exists at the lowest point of an infiltration surface, the suggested value is 0.
Surface roughness (Manning’s n)	Lower numbers indicate less surface obstruction and result in faster flow. Suggested range for a surface of decorative stones 0.03 – 0.05 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.
Surface slope (%) 	If the slope > 3%, consider using Check dams or weirs to prevent erosion of the surface under high flow velocities.
Storage 	Storage
Thickness (mm) 	Entire trench
Void ratio 	Suggest value 0.4 (unless otherwise tested) for designs using just clear stone reservoir aggregate for storage. For any design using preformed infiltration chambers, the overall ‘effective porosity’ will vary between 0.50 and 0.95 according to product-specific geometry.
Seepage rate (mm/hr) 	Infiltration rate of native soil. See design infiltration rate
Clogging factor 	Typical value of 0.5 for aged structures.
Design drawdown time (hrs) 	Suggest that this be the time within which there's a 50 % chance of recurrent rainfall? drainage time
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 other designs this height is adjusted by creating an upturn in the discharge pipe.
category: modeling
Infiltration: Testing

==Four Step Process==
Soil infiltration testing is a four-step process to obtain the necessary information for stormwater management planning and design. The four steps include:
1. Background Evaluation
*Based on available published and site specific data;
*Includes consideration of proposed development plan;
*Used to identify potential BMP types, locations and soil test locations;
*Done prior to field work; and
*On-site soil tests may be done to identify/screen potential BMP locations.
2. Test Pit or Soil Boring Observations
*Includes multiple testing locations;
*Provides an understanding of sub-surface conditions; and
*Identifies limiting conditions (e.g., aquitard, bedrock or water table elevations).
3. Infiltration Testing
*Must be conducted on-site;
*Various testing methods are available; and
*Different testing methods for screening versus verification purposes.
4. Design Considerations
*Determination of a suitable infiltration rate for design calculations; and
*Consideration of desired BMP drainage time.
==Test Pit or Soil Boring Observations==
Test pits or soil borings provide information regarding the soil horizons and overall soil conditions both horizontally and vertically in that portion of the site. Multiple observations can be made across a site at a relatively low cost and in a short time period. 
Test pit excavations or soil borings should extend to a depth of between 2.5 - 5 m below ground surface or until bedrock or fully saturated conditions are encountered. It is important that the tests provide information related to conditions at least 1.5 m below the proposed bottom elevation of the infiltration BMP. Test pit trenches should be benched at 1 m depth intervals for access and infiltration testing.
At each test location, the following conditions should be noted and described:
*Soil horizons (upper and lower boundary);
*Soil texture and colour for each horizon;
*Color patterns (mottling) and observed depth;
*Depth to water table (if encountered);
*Depth to bedrock (if encountered);
*Observations of pores or roots (size, depth);
*Estimated type and percent coarse fragments;
*Hardpan or other limiting layers; and
*Strike and dip of soil horizons.
==External links==
For further information on Borehole observation and test pits please visit the following external links:
*Oak Ridges Moraine Groundwater Management
*Northern Development, Mines, Natural Resources and Forestry's Open Data site for Geotechnical Boreholes
*Northern Development, Mines, Natural Resources and Forestry's Open Data site for Geotechnical Boreholes
* Geological Survey of Canada's Borehole Geophysical Logs
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category:Infiltration
Infiltration chambers: Gallery

Cultec_infiltration_chamber_550x550.jpg|thumb|Infiltration chambers being installed. 
20170605 164302.jpg|Chamber systems can be very large, both in terms of depth and footprint...
2012 07 24 020.jpg|...or very small as this residential soakaway/dry well.
Parking lot stormwater detention system.jpg|Parking lot stormwater detention system, partially installed. Photo credit: Arbitrarily0 
Construction for runway extension underway 121005-F-EJ686-054.jpg|Contractors construct an underground soakaway on the runway extension of Taxiway Alpha as shown here Oct. 5, 2012, at RAF Mildenhall, England. Photo credit: Karen Abeyasekere
Image from StormTech.jpg|Infiltration chambers being installed. 
East Gwillimbury.png|Example of "crate style" Infiltration chambers being installed in East Gwillimbury. Photo credit: Make-Way Environmental Technologies Inc.
category: Gallery
Infiltration chambers: Specifications

=====Plastic chambers=====
Chambers should be compliant with: 
*CSA B184-17 "Polymeric subsurface stormwater management structures".
*ASTM F2418-16a “Standard Specification for Polypropylene (PP) Corrugated Wall Stormwater Collection Chambers”. 
Allowable loads for the chambers must be determined in accordance with ASTM F2787-13 “Standard Practice for Structural Design of Thermoplastic Corrugated Wall Stormwater Collection Chambers”.
=====Concrete vaults=====
Concrete vault-type systems should be compliant with: 
*CSA A23.3-14 "Design of concrete structures",
*CSA A23.1-09/A23.2-09 (R2014) "Concrete materials and methods of concrete construction/Test methods and standard practices for concrete", and
*ASTM C858 - 10e1 "Standard Specification for Underground Precast Concrete Utility Structures".
Infiltration trenches: Gallery

Eco-Smart Infiltration trench.jpg|Trench laid in advance of the surrounding catchment being finished. This system would benefit from some geotextile on the surface to prevent sediment from accumulating before the asphalt is laid.
North Dakota State U infiltration trench.jpg|Good use of geotextile, being limited to preventing fines from entering the trench from above. 
File:Percolation trench.jpg|View of infiltration trench in U.S. Photo credit: Moreau1
category:Gallery
Iron filings (ZVI)

==What is it?==
Iron filings or zero-valent iron (ZVI) is the elemental form of iron with a zero charge carried by each atom – a result of the outer valence level being filled. ZVI is able to remove dissolved phosphorus (phosphate) from solution through precipitation. Rossetti M. Evaluation of phosphorous removals by biochar supported nano-scale zero-valent iron. 2017. Chemical Engineering Undergraduate Honors Thesis. Zero-valent iron nanoparticles (nZVI) are also used for phosphorus removal.
==How is it being used?==
No projects that use ZVI were found in Ontario. 
==Benefits==
A study was done that compared the phosphorus reduction capabilities of ZVI, biochar, biochar-supported ZVI (ZVI/BC), and biochar-supported nZVI (nZVI/BC). It was found that nZVI/BC had the highest phosphorus reduction. Using biochar-supported ZVI or nZVI improves the dispersion and stability of the iron filings. Biochar is fine-grained and highly porous, providing a large surface area to support nZVI.
Another paper reports that ZVI can remove up to 98% of influent phosphorus at low input concentrations, and at high concentrations is shown to remove up to 36% of incoming phosphorus. The phosphorus retained in the soil is mostly iron-bound, which will not be easily leached out of the system because it is very stable.Lechner L. Phosphorus Removal From Stormwater Using Zero-Valent Iron. 2016. Applied Science Masters Thesis. 
==References==
category:materials
category:phosphorus
Category: Water quality
Jar test

Specifying that aggregates for the construction of LID practices must be free from fines is important. 
But checking that the delivered materials meet specification is essential to reduce problems with construction and longer term performance. 
When possible, Construction Managers should observe the offloading of materials to watch for dust clouds. Aggregates or sand for LID construction should not give rise to clouds of dust when dumped. 
A simple jar test can be used to gauge the proportion of fines in an aggregate product before acceptance. 
Apparatus: 
*A large wide-mouthed jar - glass or clear plastic are both fine,
*Tap water, and
*The aggregate to be tested.
Method:
# Collect approximately 5 cm of material in the jar (or at least two complete layers of 50 mm clear stone), 
# Add water to around 3/4 full,
# Secure cap and shake, 
# Leave for at least 30 minutes and until the water is clear - plan to run the test overnight when possible,
# Examine the layer of sediment - if > 3 mm has been washed from 5 cm of product, the material should be rejected,
Note that the sediment may collect on top of, or at the bottom of the construction material. 
==External references==
*Heger, S. (2014). Critical Aspects During System Installation and Inspection General equipment considerations. In PMSA conference. Retrieved from http://www.psma.net/pdf/14/conference-presentations/Keys_to_Installation_(Heger).pdf
*Manitoba. (2010). Onsite Wastewater Management Systems: Field Reference Guide - JAR TEST. Retrieved from http://www.gov.mb.ca/sd/envprograms/wastewater/pdf/jar_test_reference_03_2010.pdf
Joint aggregate

The joint aggregate is an important component of Permeable Interlocking Concrete Pavement (PICP) installations, as it allows for water falling on the surface to infiltrate into the underlying layers (bedding and filter layer, base course, and sub-base reservoir). 
Construction Steps:
#Ensure paver pattern and joint width match drawing details.
#Fill in the openings and joints with ASTM No. 8 stone ( mm)* using tools such as a brush or a broom.
#Sweep the pavers to remove excess aggregate on the surface. 
#Apply additional aggregate to the openings and joints, filling them completely.
#Repeat steps 4-5 until the joint gap has been filled completely. 
Note: Some paver joint widths may be narrow and not accept most of the ASTM No. 8 stone - (Interlocking Concrete Pavement Magazine, 2007) Interlocking Concrete Pavement Magazine. 2017. Contractor Focus: Construction of Bases for Permeable Interlocking Concrete Pavements - Part I. Edition August 2007. https://www.angeluspavingstones.com/wp-content/uploads/2012/11/07_Aug_Contractor_Focus.pdf. Instead, use material that will fill the joints such as washed ASTM No. 9( mm) or No. 10 (mm) stone. 
Key Inspection Points:
*Material arrival: Ensure that material meets specifications and is free of debris and fines.
*Material installation: Ensure that material is being placed with proper equipment (brush/broom).
Mistakes to Avoid:
*Accept material that does not meets design specifications. 
*Accept material that contains fines or debris.
*Do not tamp vibrate material into joint
P1150948.jpg | Joint material being swept with a brush to fill in the joint space. (Photo source: CVC)
P1120709.jpg | Final appearance of the joint material in the permeable interlocking concrete pavement system.(Photo source: CVC)
Category:Gallery
Joint cutting

Pavement joints are important in permeable concrete systems to prevent the pavement being cracked and moved. These potential problems are caused by water, ice, salt and loads on the pavement surface. 
Construction Steps:
#Ensure joint pattern and width match drawing details. According to the (American Concrete Institute (ACI), 2013) ACI. 2013. ACI 522.1-13 Specification for Pervious Concrete Pavement https://www.concrete.org/store/productdetail.aspx?ItemID=5221U13&Format=PROTECTED_PDF&Language=English&Units=US_Units , “minimum joint width for saw cutting is 3 mm”.
#Cut the joints on the pervious concrete surface immediately after the concrete is rolled/compacted.
#Alternatively, sawcut concrete after concrete has solidified enough to avoid removing aggregate material from the concrete pavement. 
Key Inspection Points:
*Use of appropriate equipment 
*Right width and depth
Karst

thumb|Locations of karst topography in southern Ontario, Red = Known Karst; Orange = Inferred Karst; Yellow = Potential Karst
LID facilities designed to drain primarily by infiltration should not be located on karst formations or topographic features. Karst formations and topography are found in areas along the Niagara Escarpment, including the Bruce Peninsula, the Guelph/Rockwood/Elora area of Wellington County and in portions of eastern OntarioOntario Ministry of Northern Development and Mines. Karst. https://www.mndm.gov.on.ca/en/mines-and-minerals/applications/ogsearth/karst. Published 2017. Accessed October 17, 2017.. 
===Karst formations that feature undetected sinkholes, trenches and caverns, can be dangerous===
There is no one formula for defining a hazardous area associated with karst formations. Defining the “area of provincial interest” is a site-specific process. The size, extent and severity of the hazards depend on local conditionsOntario Ministry of Natural Resources. Understanding Natural Hazards.; 2001. http://www.trentu.ca/iws/documents/GLSLRS_UnderstandingNaturalHazard_Intro.pdf. Accessed October 17, 2017.. 
Karst formation character and size depends on the pH of the infiltrating water, the rate at which the rock dissolves, number of fractures and fissures in the rock, distance the water will percolate from surface to water table and the presence of impermeable layers above or below the limestone/dolomite layers.
===Karst formations can also be significant recharge zones for municipal supply aquifers===
For example, the City of Guelph, whose drinking water supply is wholly groundwater, is known to be a direct recipient of significant recharge through the areas karst formations.
==References==
Keyline design

Valleys start or head where a portion of a slope near the top of a watershed or divide becomes steeper than the general slope on either side. Thus the first part of a valley formation is steeper than the ridges or shoulders on each side that form the valley. At some point down the valley--the Keypoint--the valley slope flattens to such an extent that it becomes flatter than the ridges or shoulders on each side in the same vertical interval.
The prime purpose of the lines of cultivation on the Keyline principle is to counteract the natural rapid concentration of rainfall into the valleys by an induced drift out of the valleys. Keyline development first controls the usual water run off into valleys from the higher land, by tremendously increasing the absorption capacity of this area and diffusing the excess water, thus greatly retarding and delaying its time of concentration.
From the Keyline both up the slope and down the slope of the land, timber strips are left (or planted) on the contour at regular vertical intervals apart. The important guide for determining this vertical interval between timber strips is related to the height of the trees. If trees are 45 feet high the timber strips could be 40 feet apart vertically. This provides some overall wind protection for all the land and locates the timber strips closer together in the steep country and farther apart as the country flattens.
Even in very flat country of low scrub or mallee only 10 to 15 feet high this formula for clearing will provide greatly improved farm conditions.
LARE

The following topics have been identified from the ASLA Technical Workshop: LARE Prep Section 4 documentationAmerican Society of Landscape Architects. 2012. “ASLA Technical Workshop: LARE Prep Section 4.” https://www.asla.org/uploadedFiles/CMS/Education/LARE_Prep/Section_4_ Handouts.pdf.. Many of them are highly pertinent to Low Impact Development strategies and philosophy:
*Plans
*Slope calculations
*Contours: Rules and considerations
*Basic surveying
*Soil basics
*Grading a roadway
*Flow calculations
*Standards for accessible design
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LEED: Rainwater management

Sustainable sites: Rainwater management (up to 3 points)
*Two points (or 1 point for Healthcare) will be awarded if the project manages "the runoff from the developed site for the 95th percentile of regional or local rainfall events."
*Three points (or 2 points for Healthcare) will be awarded if the project manages "the runoff from the developed site for the 98th percentile of regional or local rainfall events."
OR
*For zero-lot-line projects only, 3 points (or 2 points for Healthcare) will be awarded if the project manages "the runoff from the developed site for the 85th percentile of regional or local rainfall events."