OPEN DRAINS - Level 1 - Visual Inspection Report

• Road Name

• Road Chainage Location

• Inspection Location (Drop Pin)
  Address

• Inspection Date

  Date

• Inspected By

• OPEN DRAIN channel profile

  Trapezoidal Channel

  Rectangular Channel

  Triangular Channel

  Irregular Channel

  Other

• OPEN DRAIN depth from road shoulder (m)

• OPEN DRAIN base width (m)

• OPEN DRAIN side slopes (i.e. 1 in 4 etc.)

• OPEN DRAIN surfacing protection material

  Select Concrete Grouted Stone Pitching Reno Rock Mattress Gabion Rock Grassed Gravel Bare Soil

  • Concrete
  • Grouted Stone Pitching
  • Reno Rock Mattress
  • Gabion
  • Rock
  • Grassed
  • Gravel
  • Bare Soil

• OPEN DRAIN longitudinal grade

  Select Flat (less than 1% grade) Moderate (1% grade to 5% grade) Steep (above 5% grade)

  • Flat (less than 1% grade)
  • Moderate (1% grade to 5% grade)
  • Steep (above 5% grade)

• General Comments

• Photos

  Media

• Road seal width (m)

• Road shoulder width (m)

• Road surface type

  Bitumen Sealed

  Asphalt

  Concrete

  Unsealed

• General Comments

• Photos

  Media

• Condition State - Severity Level Rating Descriptions

• 1= The item is in Excellent Condition - No Visual Deficiencies
  
  INDICATORS:
  - Shape – very good.
  - Vegetation – none or short grass
  - Erosion – minimal
  - Blockage – none
  - Slope – drains easily, no ponding.
  - Capacity – sufficient for major storms
  - Road Pavement has no visual signs of distress

• 2= The item is in Good Condition. No noteworthy deficiencies that affect the condition of the OPEN DRAIN. Insignificant damage and defects only with no repair works required.
  
  INDICATORS:
  - Shape – good.
  - Vegetation – up to 10%
  - Erosion – minimal
  - Blockage – minimal
  - Slope – drains, no ponding after 1 day.
  -Capacity – sufficient for major storms
  - Road Pavement has minor visual signs of distress.

• 3= The item is in Fair Condition but requires attention before the next inspection. Moderate deterioration.
  
  INDICATORS:
  - Shape – adequate.
  - Vegetation – up to 10%
  - Erosion – some
  - Blockage – sediment up to 20% of drain
  - Slope – drains, no ponding after 1 day.
  - Capacity – sufficient for major storms
  - Road Pavement has moderate visual signs of distress which identify the drain capacity is impacting the road pavement.

• 4= The item is in Poor Condition and requires attention within the next financial year. Without rectification repairs there is potential for failure leading to a critical situation. Advanced OPEN DRAIN section loss, deterioration, significant scour.
  
  INDICATORS:
  - Shape – poorly defined drain.
  - Vegetation – up to 20%
  - Erosion – significant
  - Blockage – sediment up to 40% of drain
  - Slope – ponds water up to 100 mm deep.
  - Capacity – sufficient for minor storms only
  - Road Pavement showing advanced visual signs of distress which will lead to immanent pavement failures.

• 5= The item is in Critical, imminent failure condition and requires immediate attention. Major deterioration or section loss present.
  
  INDICATORS:
  - Shape – no defined drain.
  - Vegetation – more than 20%
  - Erosion – severe scouring
  - Blockage – sediment more than 40%
  - Slope – ponds water and does not drain.
  - Capacity – overtops frequently
  - Road Pavement failures have occurred (Potholes, Cracking, Rutting, Scour, Edge Drop Off etc.)

OPEN DRAIN - Hydraulic Condition

OPEN DRAIN - Shape of Channel

• Condition State - Severity Level

• Management Required

  Select No Repair Works Minor Repair works Major repair works

  • No Repair Works
  • Minor Repair works
  • Major repair works

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

OPEN DRAIN - Scouring / Erosion of Channel

• Condition State - Severity Level

• Management Required

  Select No Repair Works Minor Repair works Major repair works

  • No Repair Works
  • Minor Repair works
  • Major repair works

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

OPEN DRAIN - Flow Blockages (siltation / debris / vegetation) of Channel

• Condition State - Severity Level

• Management Required

  Select No clearing of debris / vegetation required Minor clearing of debris /vegetation Major clearing of debris /vegetation

  • No clearing of debris / vegetation required
  • Minor clearing of debris /vegetation
  • Major clearing of debris /vegetation

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

OPEN DRAIN - Capacity of Channel

• Condition State - Severity Level

• Management Required

  Select Capacity sufficient for most storm events Capacity should be increased to improve overall immunity Capacity insufficient drain needs to be formed or regraded and capacity increased to improve overall immunity Cross-road drainage needs to be installed - Flow can outlet properly across road.

  • Capacity sufficient for most storm events
  • Capacity should be increased to improve overall immunity
  • Capacity insufficient drain needs to be formed or regraded and capacity increased to improve overall immunity
  • Cross-road drainage needs to be installed - Flow can outlet properly across road.

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

• OPEN DRAIN Vulnerability State - Rating Descriptions

• 1= NOT VULNERABLE - Description: The drain is constructed with durable materials and is located in areas with minimal flood risk. It requires little to no maintenance.
  
  INDICATORS:
  - High durability.
  - Minimal maintenance.
  - Low flood risk.

• 2=SLIGHTLY VULNERABLE - Description: The drain may experience minor blockages during typical rainy seasons. Small signs of wear are present but do not affect functionality.
  
  INDICATORS:
  - Minor wear and tear.
  - Occasional debris blockages.
  - Routine maintenance required.

• 3= MODERATLEY VULNERABLE - Description: The drain is prone to debris accumulation during storms, leading to temporary water pooling. Material degradation occurs quicker, necessitating regular upkeep.
  
  INDICATORS:
  - Frequent debris blockages.
  - Temporary pooling.
  - Regular maintenance and repairs.

• 4= HIGHLY VULNERABLE - Description: The drain is at significant risk from heavy rainfall and flooding. It experiences frequent blockages and structural wear.
  
  INDICATORS:
  - Frequent blockages.
  - Significant erosion and wear.
  - High maintenance needs.

• 5 = VERY VULNERABLE - Description: The drain is in areas prone to severe weather events and flooding. It often fails during extreme conditions, requiring extensive repairs or redesign.
  
  INDICATORS:
  - High risk of severe weather impact.
  - Frequent and severe blockages.
  - Structural failure likely during extreme events.
  - Extensive maintenance or redesign needed.

Exposure to Increased Flooding and Rainfall Intensity Vulnerability

• Increased Flooding and Rainfall Intensity: Samoa's location in the Pacific exposes it to frequent tropical storms and cyclones, which are expected to increase in intensity due to climate change. The increased rainfall can lead to higher water volumes that existing OPEN DRAINS might not be designed to handle, potentially causing overtopping or structural failure.

• How vulnerable is the OPEN DRAIN to the potential of flow overtopping the road?

  Select High Chance of Flow Overtopping Road Likely Chance of Flow Overtopping Roadway Unlikely Chance of Flow Overtopping Roadway

  • High Chance of Flow Overtopping Road
  • Likely Chance of Flow Overtopping Roadway
  • Unlikely Chance of Flow Overtopping Roadway

• If flow was to overtop the roadway would the pavement material be adequate enough to withstand overtopping flows on the road?

  Select High Resilience - Concrete Pavement Medium Resilience - Asphalt Pavement Low resilience - Bitumen Sealed Pavement Failure Likely - Unsealed Pavement

  • High Resilience - Concrete Pavement
  • Medium Resilience - Asphalt Pavement
  • Low resilience - Bitumen Sealed Pavement
  • Failure Likely - Unsealed Pavement

• If the road was required to be closed for an extended period would it cause significant effect to the road network (are alternative routes available)

  Select Alternative Route Available - Minimal Delays Alternative Route Available - Significant Delays No Alternative route Available - Extensive delays

  • Alternative Route Available - Minimal Delays
  • Alternative Route Available - Significant Delays
  • No Alternative route Available - Extensive delays

• Is there adequate space to add additional CAPACITY to the existing OPEN DRAIN to increase immunity?

  Select Yes - Adequate Space Available without need for extensive inlet/outlet channel works Yes - Adequate Space Available but will require extensive inlet/outlet channel works No- Will require extensive roadworks and channel works

  • Yes - Adequate Space Available without need for extensive inlet/outlet channel works
  • Yes - Adequate Space Available but will require extensive inlet/outlet channel works
  • No- Will require extensive roadworks and channel works

• Vulnerability Assessment of OPEN DRAIN for Increased Flooding and Rainfall Intensity

  1= NOT VULNERABLE

  2= SLIGHTLY VULNERABLE

  3= MODERATELY VULNERABLE

  4= HIGHLY VULNERABLE

  5= VERY VULNERABLE

• General Comments

• Photos

  Media

Exposure to Increased Sediment and Debris Flow

• Stronger storms and more intense rainfall can increase the amount of sediment and debris washed into OPEN DRAINS. This buildup can obstruct water flow, leading to water backup and increased pressure on OPEN DRAINS, which may result in blockages or even structural damage.

• How vulnerable is the OPEN DRAIN to the potential of increased sediment and debris flow causing future blockage

  1= NOT VULNERABLE

  2= SLIGHTLY VULNERABLE

  3= MODERATELY VULNERABLE

  4= HIGHLY VULNERABLE

  5= VERY VULNERABLE

• General Comments

• Photos

  Media

Exposure to Corrosion from Saltwater

• OPEN DRAINS, especially those near the coast, are vulnerable to corrosion or erosion due to increased exposure to saltwater from sea spray and storm surges. Corrosion and erosion can weaken the structural integrity of OPEN DRAINS reducing their lifespan and effectiveness.

• How vulnerable is the OPEN DRAIN to Corrosion Potential

  1= NOT VULNERABLE

  2= SLIGHTLY VULNERABLE

  3= MODERATELY VULNERABLE

  4= HIGHLY VULNERABLE

  5= VERY VULNERABLE

• How vulnerable is the OPEN DRAIN to Erosion Potential

  1= NOT VULNERABLE

  2= SLIGHTLY VULNERABLE

  3= MODERATELY VULNERABLE

  4= HIGHLY VULNERABLE

  5= VERY VULNERABLE

• General Comments

• Photos

  Media

Exposure to Sea Level Rise and Storm Surges

• Rising sea levels and more powerful storm surges can exacerbate coastal flooding, especially affecting OPEN DRAINS near the coastline. This leads to more frequent inundation affecting the OPEN DRAINS CAPACITY.

• How vulnerable is the OPEN DRAIN to potential sea level rise or storm surge effects.

  1= NOT VULNERABLE

  2= SLIGHTLY VULNERABLE

  3= MODERATELY VULNERABLE

  4= HIGHLY VULNERABLE

  5= VERY VULNERABLE

• General Comments

• Photos

  Media

Roadside Hazards - Steep Slopes, Drop Offs or Objects

• Does the roadside OPEN DRAIN have steep slopes, drops offs or large objects within 4.0m of the trafficable lane which could be considered hazardous?

  Yes

  No

  N/A

• What rectification should be carried out to reduce the hazardous situation?

  Select Consider urban underground drainage system (kerb, pit and pipe) Reconstruct drain to increase offset from trafficable lane Flatten roadside batter and reprofile open drain to suit Relocate or remove large object Install Guardrail or Fencing to protect the hazard Install Guideposts, signage and linemarking to better delineate the Hazard

  • Consider urban underground drainage system (kerb, pit and pipe)
  • Reconstruct drain to increase offset from trafficable lane
  • Flatten roadside batter and reprofile open drain to suit
  • Relocate or remove large object
  • Install Guardrail or Fencing to protect the hazard
  • Install Guideposts, signage and linemarking to better delineate the Hazard

• Condition State - Severity Level

• Management Required

  No Repair Works

  Minor Repair works

  Major repair works

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

Roadside Guardrails and Fencing

• Does the roadside OPEN DRAIN have guardrail or fencing

  Yes

  No

  N/A

• Is the Guardrail or Fencing Intact and Properly Installed

  Yes

  No

  N/A

• Condition State - Severity Level

• Management Required

  No Repair Works

  Minor Repair works

  Major repair works

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

Signage and Guideposts

• Does the roadside OPEN DRAIN have any Signage or Guideposts Installed

  Yes

  No

  N/A

• Is the Signage and Guideposts Intact and Properly Installed

  Yes

  No

  N/A

• Condition State - Severity Level

• Management Required

  No Repair Works

  Minor Repair works

  Major repair works

• General Comments - Provide Comments on Possible Rectification Description

• Photos

  Media

• Have Issues been identified that require Immediate Emergency Rectification (i.e. An Immediate Public Safety Issue)

  Yes

  No

  N/A

• Details of Emergency Rectification Required

• Overall Assessment of the roadside OPEN DRAIN Condition State - Severity Level

• Monitoring Required

  3 monthly

  6 monthly

  12 monthly

  24 monthly

• General Comments

• Completed Signature

  Sign