Stormwater pond/wetland - construction inspection checklist.
Link to this table
To access an Excel version of form (for field use), click here.
Project: | ||
Location: | ||
Site Status: | ||
Date: | ||
Time: | ||
Inspector: | ||
Construction Sequence | Satisfactory/Unsatisfactory | Comments |
---|---|---|
1. Pre-Construction/Materials and Equipment | ||
Pre-construction meeting | ||
Pipe and appurtenances on-site prior to construction and dimensions checked | ||
1. Material (including protective coating, if specified) | ||
2. Diameter | ||
3. Dimensions of metal riser or pre-cast concrete outlet structure | ||
4. Required dimensions between water control structures (orifices, weirs, etc.) are in accordance with approved plans | ||
5. Barrel stub for prefabricated pipe structures at proper angle for design barrel slope | ||
6. Number and dimensions of prefabricated antiseep collars | ||
7. Watertight connectors and gaskets | ||
8. Outlet drain valve | ||
Project benchmark near pond site | ||
Facility location staked out | ||
Equipment for temporary de-watering | ||
Temporary erosion and sediment control in place | ||
2. Subgrade Preparation | ||
Area beneath embankment stripped of all vegetation, topsoil, and organic matter | ||
3. Pipe Installation | ||
Method of installation detailed on plans | ||
A. Bed preparation | ||
Installation trench excavated with specified side slopes | ||
Stable, uniform, dry subgrade of relatively impervious material (If subgrade is wet, contractor shall have defined steps before proceeding with installation) | ||
Invert at proper elevation and grade | ||
B. Pipe placement | ||
Metal / plastic pipe | ||
1. Watertight connectors and gaskets properly installed | ||
2. Anti-seep collars properly spaced and having watertight connections to pipe | ||
3. Backfill placed and tamped by hand under “haunches” of pipe | ||
4. Remaining backfill placed in max. 8 inch lifts using small power tamping equipment until 2 feet cover over pipe is reached | ||
Concrete pipe | ||
1. Pipe set on blocks or concrete slab for pouring of low cradle | ||
2. Pipe installed with rubber gasket joints with no spalling in gasket interface area | ||
3. Excavation for lower half of anti-seep collar(s) with reinforcing steel set | ||
4. Entire area where anti-seep collar(s) will come in contact with pipe coated with mastic or other approved waterproof sealant | ||
5. Low cradle and bottom half of anti-seep collar installed as monolithic pour and of an approved mix | ||
6. Upper half of anti-seep collar(s) formed with reinforcing steel set | ||
7. Concrete for collar of an approved mix and vibrated into place (protected from freezing while curing, if necessary) | ||
8. Forms stripped and collar inspected for honeycomb prior to backfilling. Parge if necessary. | ||
C. Backfilling | ||
Fill placed in maximum 8 inch lifts | ||
Backfill taken minimum 2 feet above top of antiseep collar elevation before traversing with heavy equipment | ||
4. Riser / Outlet Structure Installation | ||
Riser located within embankment | ||
A. Metal riser | ||
Riser base excavated or formed on stable subgrade to design dimensions | ||
Set on blocks to design elevations and plumbed | ||
Reinforcing bars placed at right angles and projecting into sides of riser | ||
Concrete poured so as to fill inside of riser to invert of barrel | ||
B. Pre-cast concrete structurer | ||
Dry and stable subgrade | ||
Riser base set to design elevation | ||
If more than one section, no spalling in gasket interface area; gasket or approved caulking material placed securely | ||
Watertight and structurally sound collar or gasket joint where structure connects to pipe spillway | ||
C. Poured concrete structure | ||
Footing excavated or formed on stable subgrade, to design dimensions with reinforcing steel set | ||
Structure formed to design dimensions, with reinforcing steel set as per plan | ||
Concrete of an approved mix and vibrated into place (protected from freezing while curing, if necessary) | ||
Forms stripped & inspected for honeycomb prior to backfilling; parge if necessary | ||
5. Embankment Construction | ||
Fill material | ||
Compaction | ||
Embankment | ||
1. Fill placed in specified lifts and compacted with appropriate equipment | ||
2. Constructed to design cross-section, side slopes and top width | ||
3. Constructed to design elevation plus allowance for settlement | ||
6. Impounded Area Construction | ||
Excavated / graded to design contours and side slopes | ||
Inlet pipes have adequate outfall protection | ||
Forebay(s) constructed per plans | ||
Pond benches construction per plans | ||
7. Earth Emergency Spillway Construction | ||
Spillway located in cut or structurally stabilized with riprap, gabions, concrete, etc. | ||
Excavated to proper cross-section, side slopes and bottom width | ||
Entrance channel, crest, and exit channel constructed to design grades and elevations | ||
8. Outlet Protection | ||
A. End section | ||
Securely in place and properly backfilled | ||
B. Endwall | ||
Footing excavated or formed on stable subgrade, to design dimensions and reinforcing steel set, if specified | ||
Endwall formed to design dimensions with reinforcing steel set as per plan | ||
Concrete of an approved mix and vibrated into place (protected from freezing, if necessary) | ||
Forms stripped and structure inspected for honeycomb prior to backfilling; parge if necessary | ||
C. Riprap apron / channel | ||
Apron / channel excavated to design cross-section with proper transition to existing ground | ||
Filter fabric in place | ||
Stone sized as per plan and uniformly place at the thickness specified | ||
9. Vegetative Stabilization | ||
Approved seed mixture or sod | ||
Proper surface preparation and required soil mendments | ||
Excelsior mat or other stabilization, as per plan | ||
10. Miscellaneous | ||
Drain for ponds having a permanent pool | ||
Trash rack / anti-vortex device secured to outlet structure | ||
Trash protection for low flow pipes, orifices, etc. | ||
Fencing (when required) | ||
Access road | ||
Set aside for clean-out maintenance | ||
11. Stormwater Wetlands | ||
Adequate water balance | ||
Variety of depth zones present | ||
Approved pondscaping plan in place and budget for additional plantings | ||
Plants and materials ordered 6 months prior to construction | ||
Construction planned to allow for adequate planting and establishment of plant community (April-June planting window) | ||
12. Final Inspection | ||
Construction sediment removed from settling basin | ||
Contributing drainage area stabilized | ||
Vegetation established per specifications | ||
Inlet and outlet structures operational | ||
Comments: | ||
Actions to be Taken: |
This page was last edited on 30 April 2024, at 19:20.