m |
m |
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Line 64: | Line 64: | ||
<td>[[File:Curved channels.png|center|100px]]</td> | <td>[[File:Curved channels.png|center|100px]]</td> | ||
<td>Geomorphically stabilize channels</td> | <td>Geomorphically stabilize channels</td> | ||
− | <td>Cross vanes, fish steps, curvilinear channel restoration, reinforced streambank, grade adjustments, revetments, root wads</td> | + | <td>Cross vanes, fish steps, curvilinear channel restoration (see image), reinforced streambank, grade adjustments, revetments, root wads</td> |
<td>None</td> | <td>None</td> | ||
</tr> | </tr> | ||
Line 71: | Line 71: | ||
<td>[[File:Off line pool.png|center|100px]]</td> | <td>[[File:Off line pool.png|center|100px]]</td> | ||
<td>Use off-line storage in available floodplain, open space</td> | <td>Use off-line storage in available floodplain, open space</td> | ||
− | <td>Off-line pools, enhanced floodplains, wetland restoration/preservation</td> | + | <td>Off-line pools (see image), enhanced floodplains, wetland restoration/preservation</td> |
<td>None if kept away from areas | <td>None if kept away from areas | ||
where vehicles expected to travel or go off of the road</td> | where vehicles expected to travel or go off of the road</td> | ||
Line 79: | Line 79: | ||
<td>[[File:Under street infiltration trench.png|center|100px]]</td> | <td>[[File:Under street infiltration trench.png|center|100px]]</td> | ||
<td>Use sub-grade storage with or without perforations to allow for storage and infiltration where drainage determined not to impact road structure</td> | <td>Use sub-grade storage with or without perforations to allow for storage and infiltration where drainage determined not to impact road structure</td> | ||
− | <td>Under street infiltration trenches, vault storage to replace surface ponds, rest areas parking lots</td> | + | <td>Under street infiltration trenches (see image), vault storage to replace surface ponds, rest areas parking lots</td> |
<td>Maintenance crew will need confined-space training</td> | <td>Maintenance crew will need confined-space training</td> | ||
</tr> | </tr> |
BMP options for highway and road runoff management
Link to this table
BMP Type | Objective | BMP Examples | Safety Considerations |
---|---|---|---|
Diffuse flow energy from concentrated roadway surface before discharging over a slope; reinforce discharge point and slopes; promote sheet flow | Compost sock (see image), bio-slope, outlet reinforcement, spray mulch, compost rip rap matrix (between rocks) | May increase slipperiness of shoulder slope | |
Filter litter and debris from flow as it enters catch basins; preferably with pollutant sorbents 2 | Catch basin insert (see image); hooded outlet pipe; oil and grease separator | Might become heavy for maintenance crews to lift; must be cleaned to prevent clogging | |
Route runoff through a screen or filter material to remove litter and treat particulate, and the associated nutrients, toxics and hydrocarbons | Gross Solids Removal Device (GSRD) (see image), compost tube inside of rock weep, | Often contained in confined space; maintenance crew will need confined space training | |
Diffuse heat from road and parking surfaces prior to discharge to sensitive waters | Geotextile wrapped rip rap thermal tube (see image), infiltration trench | None | |
Provide vegetated swale drainage systems with low head grade breaks in rural sections | “Living ditch” (see image), check dams (rip rap, bio-weeper, bio-ditch filter) | Can hold water for a time after runoff occurs so need to keep design depths shallow; grade breaks can be obstruction hazard to recreational vehicles using swale | |
Retrofit stored water BMPs with proper outlet and skimmer devices | Particulate skimmer (see image), baffle weir, Faircloth skimmer (proprietary device) | None | |
Use pervious paving material in areas that will support it | Pervious asphalt and concrete (see image), paving blocks | None for pavement; blocks can pose walking problems if not designed properly; recommendation for minimal salt use could mean ice might be present for short periods | |
Route water to bioretention, filtration or infiltration areas where conditions appropriate | Rain garden (see image) | Near-road locations could possibly impede vision at intersections if vegetation not kept low; water might collect adjacent to roadway | |
Geomorphically stabilize channels | Cross vanes, fish steps, curvilinear channel restoration (see image), reinforced streambank, grade adjustments, revetments, root wads | None | |
Use off-line storage in available floodplain, open space | Off-line pools (see image), enhanced floodplains, wetland restoration/preservation | None if kept away from areas where vehicles expected to travel or go off of the road | |
Use sub-grade storage with or without perforations to allow for storage and infiltration where drainage determined not to impact road structure | Under street infiltration trenches (see image), vault storage to replace surface ponds, rest areas parking lots | Maintenance crew will need confined-space training |
1Use of proprietary devices or images merely for illustrative purposes and does not mean endorsement of a product
2Note that housekeeping practices like street sweeping and chemical use are discussed in the Pollution Prevention section