Difference between revisions of "Pretreatment"

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</ul>
</ul>
===Concentrated underground flow===
===Concentrated underground flow===
<p>Oil and grit separators (OGS) are devices which use physical principles to improve water quality. Typically these are underground chambers installed in catchbasins or manholes. Many commercial and custom configurations exist for both new installations and retrofit scenarios.  
<h4>Oil and grit seperators (OGS)</h4>
*One example might employ baffles within a tank or chamber:
<p>OGS are devices which use physical principles to improve water quality. Typically these are underground chambers installed in catch basins or manholes. Many commercial and custom configurations exist for both new installations and retrofit scenarios. </p>
**The first baffle slows the incoming water flow, encouraging any larger, heavier particles to drop out of the water,
<p>One method is to incorporate baffles within a tank or chamber:
**A second baffle skims the surface of the water, preventing floating debris, oils and grease from passing,
*Another option is a hydrodynamic device, which forces the incoming water flow into a circular vortex:
**This motion forces the larger, heavier particles are outwards and downwards into a lower chamber,
**Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber. </p>
===External Links===
<ul>
<ul>
<li>[https://www.cmhc-schl.gc.ca/en/inpr/su/waho/waho_015.cfm CMHC OGS Effectiveness Study]</li>
<li>The first baffle slows the incoming water flow, encouraging any larger, heavier particles to drop out of the water, </li>
<li>A second baffle skims the surface of the water, preventing floating debris, oils and grease from passing. </li>
</ul>
Proprietary examples of baffle systems (not verified): [http://upstreamtechnologies.us/products/safl.shtml| SAFL baffle]
</p>
<p>Another option is a hydrodynamic device, which forces the incoming water flow into a circular vortex:
<ul>
<li>The vortex motion forces the larger, heavier particles are outwards and downwards into a lower chamber, </li>
<li>Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber. </li>
</ul>
</ul>
<h4>Proprietary Systems</h4>
Proprietary examples of <strong>[http://etvcanada.ca/| verified]</strong> hydrodynamic systems : 
[http://etvcanada.ca/| Verified Environmental Technologies]
<ul>
<ul>
<li>[http://www.cbshield.com/| CB Shield]</li>
<li>[http://www.conteches.com/Products/Stormwater-Management/Treatment/CDS.aspx| CDS]</li>
<li>[http://www.conteches.com/Products/Stormwater-Management/Treatment/CDS.aspx| CDS]</li>
<li>[https://www.hydro-int.com/en/products/downstream-defender| Downstream defender]</li>
<li>[https://www.hydro-int.com/en/products/downstream-defender| Downstream defender]</li>
<li>[http://nextstorm.ca/sdd/| SDD]</li>
<li>[http://nextstorm.ca/sdd/| SDD]</li>
</ul>
</ul>
Other technologies, where inclusion of a company or product does not constitute endorsement. <br>
Proprietary examples of other hydrodynamic systems (not verified): [http://www.imbriumsystems.com/stormwater-treatment-solutions/stormceptor-systems| Stormceptor]
You may inform us of any omissions or broken links using the button below:
<h4>Inline filters</h4>
<p>Using technology adopted from water treatment plants. </p>
<ul>
<li>[http://www.imbriumsystems.com/stormwater-treatment-solutions/jellyfish-filter| Jellyfish]</li>
</ul>
<h4>Catchbasin inserts</h4>
<p>Great for retrofitting situations, to improve water quality:</p>
Proprietary examples of <strong>[http://etvcanada.ca/| verified]</strong> inserts:
<ul>
<li>[http://www.cbshield.com/| CB Shield]</li>
</ul>
Proprietary examples of other inserts (not verified):
<ul>
<ul>
<li>[http://upstreamtechnologies.us/products/safl.shtml| SAFL baffle]</li>
<li>[http://upstreamtechnologies.us/products/snout.shtml| Snout]</li>
<li>[http://upstreamtechnologies.us/products/snout.shtml| Snout]</li>
<li>[http://www.imbriumsystems.com/stormwater-treatment-solutions/stormceptor-systems| Stormceptor]</li>
</ul>
</ul>
===Resources===
<ul>
<li>[https://www.cmhc-schl.gc.ca/en/inpr/su/waho/waho_015.cfm CMHC OGS Effectiveness Study]</li>
</ul>
This article is particularly heavy on proprietary systems and information. Please inform us of any omissions or broken links using the button below:


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[[category: Pretreatment]]
[[category: Pretreatment]]

Revision as of 13:45, 3 August 2017

Overland sheet flow[edit]

The following pretreatements are recommended where sheet flow is being directed to a BMP (typically a bioretention cell) from the edge of an impermeable surface such as an asphalt parking lot or a paved plaza:

A gravel diaphragm typically requires less setback between the catchment and the BMP. Where space permits, these two designs can be used in combination to even greater effect!

Concentrated overland flow[edit]

Where a curb cut, a disconnected downspout or a swale directs surface water to a point, increasing the flow rate, one or more of the following pretreatments should be considered:

Concentrated underground flow[edit]

Oil and grit seperators (OGS)

OGS are devices which use physical principles to improve water quality. Typically these are underground chambers installed in catch basins or manholes. Many commercial and custom configurations exist for both new installations and retrofit scenarios.

One method is to incorporate baffles within a tank or chamber:

  • The first baffle slows the incoming water flow, encouraging any larger, heavier particles to drop out of the water,
  • A second baffle skims the surface of the water, preventing floating debris, oils and grease from passing.

Proprietary examples of baffle systems (not verified): SAFL baffle

Another option is a hydrodynamic device, which forces the incoming water flow into a circular vortex:

  • The vortex motion forces the larger, heavier particles are outwards and downwards into a lower chamber,
  • Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber.

Proprietary examples of verified hydrodynamic systems :

Proprietary examples of other hydrodynamic systems (not verified): Stormceptor

Inline filters

Using technology adopted from water treatment plants.

Catchbasin inserts

Great for retrofitting situations, to improve water quality:

Proprietary examples of verified inserts:

Proprietary examples of other inserts (not verified):

Resources[edit]

This article is particularly heavy on proprietary systems and information. Please inform us of any omissions or broken links using the button below:

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