Difference between revisions of "Construction specifications for Infiltration trench"
Rain gardens (bioretention) 101 > Calculating credits for bioretention > Construction specifications for Infiltration trench

Latest revision as of 14:46, 11 December 2022

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Construction specifications for infiltration

CADD based details for pond systems are contained in the section on drawings. The following details, with specifications, have been created for infiltration systems:

infiltration basin
infiltration trench
subsurface infiltration system
inlet/outlet structures

Construction specifications

Given that the construction of infiltration practices incorporates techniques or steps which may be considered non-standard, it is RECOMMENDED that the construction specifications include the following format and information.

Temporary erosion control

Installation prior to site disturbance
Catch basin/inlet protection
Use of BMP as temporary sedimentation basin

Excavation, backfill and grading

Timing of grading of infiltration practices (relative to total site development)
Use of low-impact, earth moving equipment
Controls to ensure site is not over-excavated
Restoration in the event of sediment accumulation during construction of practice
Gravel backfill specifications
Gravel filter specifications
Filter fabric specifications
Observation well specifications

Native plants, planting and transplanting

Site preparation of planting areas
Timing of native seeding and native planting
Weed control
Watering of plant material

Warning: It is REQUIRED that infiltration systems not be excavated to final grade until the contributing drainage area has been constructed and fully stabilized.

Construction sequence scheduling

Temporary construction access
Location of silt fence installation to protect BMPs and downgradient receiving waters
Removal and storage of excavated material
Installation of underground utilities
Rough grading
Seeding and mulching disturbed areas
Road construction
Final grading
Site stabilization
Installation of semi-permanent and permanent erosion control measures
Silt fence removal (often forgotten but an essential step)

Construction observation

Adherence to construction documents
Verification of physical site conditions
Erosion control measures installed appropriately

Related pages

@@ Line 1: / Line 1: @@
-==Construction Details==
+#REDIRECT [[Construction specifications for infiltration ]]
-<p>CADD based details for pond systems are contained in the section on [[Computer-aided design and drafting (CAD/CADD) drawings]]. The following details, with specifications, have been created for infiltration systems:</p>
-*Infiltration [[Glossary#B|Basin]]
+CADD based details for pond systems are contained in the section on [[CADD images for individual best management practices|drawings]]. The following details, with specifications, have been created for infiltration systems:
-*Infiltration Trench
+*infiltration basin
-*Subsurface Infiltration System
+*infiltration trench
-*Inlet/outlet Structures
+*subsurface infiltration system
-===Construction Specifications===
+*inlet/outlet structures
-<p>Given that the construction of [[Glossary#I|infiltration]] practices incorporates techniques or steps which may be considered non-standard, it is ''RECOMMENDED'' that the construction specifications include the following format and information:</p>
-===Temporary [[Glossary#E|Erosion]] Control===
+==Construction specifications==
+Given that the construction of [[Glossary#I|infiltration]] practices incorporates techniques or steps which may be considered non-standard, it is ''RECOMMENDED'' that the construction specifications include the following format and information.
+===Temporary erosion control===
 *Installation prior to site disturbance
 *Catch [[Glossary#B|basin]]/inlet protection
-*Use of [[Glossary#B|BMP]] as temporary sedimentation [[Glossary#B|basin]]/
+*Use of [[Glossary#B|BMP]] as temporary sedimentation basin
-===Excavation, Backfill and Grading===
+===Excavation, backfill and grading===
 *Timing of grading of infiltration practices (relative to total site development)
 *Use of low-impact, earth moving equipment
@@ Line 20: / Line 24: @@
 *Filter fabric specifications
 *Observation well specifications
-===Native Plants, Planting and Transplanting===
+===Native plants, planting and transplanting===
 *Site preparation of planting areas
 *Timing of native seeding and native planting
 *Weed control
 *Watering of plant material
-{{alert|It is REQUIRED that infiltration systems not be excavated to final grade until the contributing drainage area has been constructed and fully stabilized.|alert-caution}}
+{{alert|It is REQUIRED that infiltration systems not be excavated to final grade until the contributing drainage area has been constructed and fully stabilized.|alert-danger}}
-=Construction Sequence Scheduling===
+===Construction sequence scheduling===
 *Temporary construction access
-*Location of [[Glossary#S|silt fence]] installation to protect [[Glossary#B|BMP]]s and downgradient receiving waters
+*Location of [[Glossary#S|silt fence]] installation to protect BMPs and downgradient [[Glossary#R|receiving waters]]
 *Removal and storage of excavated material
 *Installation of underground utilities
@@ Line 37: / Line 43: @@
 *Site stabilization
 *Installation of semi-permanent and permanent [[Glossary#E|erosion]] control measures
-*[[Glossary#S|Silt fence]] removal (often forgotten but an essential step)
+*Silt fence removal (often forgotten but an essential step)
-===Construction Observation===
+===Construction observation===
 *Adherence to construction documents
 *Verification of physical site conditions
-*[[Glossary#E|Erosion]] control measures installed appropriately
+*Erosion control measures installed appropriately
-====Avoid excessive compaction====
-{{alert|It is ''REQUIRED'' that in order to prevent soil compaction, the proposed [[Glossary#I|infiltration]] area be staked off and marked during construction to prevent heavy equipment and traffic from traveling over it.|alert-danger}}
-<p>In addition, it is ''HIGHLY RECOMMENDED'' that the side walls of dry wells and [[Glossary#I|infiltration]] trenches be roughened if they have been smeared by heavy equipment</p>
-====Stabilize Vegetation Before and After Construction====
-<p>Excessive [[Glossary#S|sediment]] loadings can occur without the use of proper [[Glossary#E|erosion]] and [[Glossary#S|sediment]] control practices during the construction process.</p>
-{{alert|It is ''REQUIRED'' that upland drainage areas be properly stabilized with a thick layer of vegetation, particularly immediately following construction, to reduce [[Glossary#S|sediment]] loads.|alert-danger}}
-{{alert|If [[Glossary#I|infiltration]] practices are in-place during construction activities, it is ''REQUIRED'' that [[Glossary#S|sediment]] and [[Glossary#R|runoff]] be kept away the [[Glossary#I|infiltration]] area, such as with diversion berms and soil-stabilizing vegetation around the perimeter of the practice.|alert-danger}}
-====Correctly Install Filter Fabrics====
-<p>Large tree roots should be trimmed flush with the sides of dry wells and [[Glossary#I|infiltration]] trenches to prevent puncturing or tearing of the filter fabric during subsequent installation procedures. When laying out the geotextile, the width should include sufficient material to compensate for perimeter irregularities in the dry well or trench and for a 6-inch minimum top overlap. The filter fabric itself should be tucked under the sand layer on the bottom of the dry well of [[Glossary#I|infiltration]] trench, and stones or other anchoring objects should be placed on the fabric at the trench sides to keep the excavation open during windy periods. Voids may occur between the fabric and the excavated sides of the practice. Natural soils should be placed in any voids to ensure fabric conformity to the excavation sides.</p>
-====Carefully Finish Final Grading====
-<p>Initial [[Glossary#I|infiltration]] [[Glossary#B|basin]] excavation should be carried to within 2 feet of the final elevation of the [[Glossary#B|basin]] floor.</p>
-{{alert|It is ''REQUIRED'' that [[Glossary#I|infiltration]] systems not be excavated to final grade until the contributing drainage area has been constructed and fully stabilized.|alert-danger}}
-<p>The final phase excavation should remove all accumulated [[Glossary#S|sediment]] and be done by light tracked equipment to avoid compaction of the [[Glossary#B|basin]] floor and provide a well-aerated, highly porous surface texture. </p>
-====Keep infiltration practices “Off-line” until construction Is complete====
-{{alert|It is ''REQUIRED'' that [[Glossary#S|Ssediment]] and [[Glossary#R|runoff]] be kept completely away from the [[Glossary#I|infiltration]] area during construction. Thus, [[Glossary#I|infiltration]] practices should never serve as [[Glossary#S|Ssediment]] control devices during site construction.|alert-danger}}
-<p>It is ''HIGHLY RECOMMENDED'' that construction of [[Glossary#S|Ssediment]] practices be suspended during snowmelt or rainfall, in order to prevent soil smearing, clumping, or compaction.</p>
+<noinclude>
+==Related pages==
+*[[Overview for Infiltration trench]]
+*[[Types of Infiltration trench]]
+*[[Design criteria for Infiltration trench]]
+*[[Construction specifications for Infiltration trench]]
+*[[Operation and maintenance of Infiltration trench]]
+*[[Assessing the performance of infiltration trenches and basins]]
+*[[Cost-benefit considerations for Infiltration trench]]
+*[[External resources for Infiltration trench ]]
+*[[References for infiltration]]
-====Establish Permanent Vegetation====
+[[Category:Level 3 - Best management practices/Specifications and details/Construction specifications]]
-*Establishing dense vegetation on the basin side slopes is ''HIGHLY RECOMMENDED'', to reduce [[Glossary#E|erosion]] and sloughing and
+</noinclude>
-*Provide a natural means of maintaining relatively high [[Glossary#|Iinfiltration]] rates. [[Glossary#V|Vegetative cover]] at inflow points to the {Glossary#B|basin]] is also ''HIGHLY RECOMMENDED'' to provide [[Glossary#E|erosion]] protection and reduce [[Glossary#S|sediment]] accumulation. The use of native grasses is ''RECOMMENDED'' for seeding primarily due to their adaptability to local climates and soil conditions.
-*Inspections during construction are needed to ensure that the [[Glossary#|Iinfiltration]] practice is built in accordance with the approved design and standards and specifications. Detailed inspection checklists should be used that include sign-offs by qualified individuals at critical stages of construction to ensure that the contractor’s interpretation of the plan is acceptable to the designer.

Difference between revisions of "Construction specifications for Infiltration trench" Rain gardens (bioretention) 101 > Calculating credits for bioretention > Construction specifications for Infiltration trench