Overview: Post-Rehab QA/QC at Hinterland Group

Hinterland Group is committed to delivering top-quality water and sewer infrastructure projects across the southeastern United States through rigorous post-rehabilitation (post-rehab) quality assurance and quality control (QA/QC) processes. These QA/QC procedures include strict acceptance criteria, detailed CCTV (Closed Circuit Television) pipeline inspection and verification, and, where regulations require, comprehensive air/water pressure or leak testing. These processes ensure every rehabilitation project meets performance expectations and industry standards, with a focus on long-term reliability and regulatory compliance.

All QA/QC activities are performed by certified, in-house specialists using advanced equipment and industry best practices, reflecting Hinterland Group’s dedication to safety, performance, and client satisfaction.

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Elements of Post-Rehab QA/QC

1. Acceptance Criteria

Acceptance criteria are the predetermined standards each rehabilitation project must meet before it is deemed complete. Hinterland Group defines these criteria in advance, working with clients to ensure all regulatory and design requirements are addressed. Key acceptance parameters include:

Structural integrity of the pipeline (no visible deformities, cracks, or blisters)
Proper curing or setting of rehabilitation materials
Full re-establishment of flow capacity
No infiltration/exfiltration or signs of leakage
All lateral/service connections reinstated and watertight
Internal diameter and shape adheres to specifications
Full compliance with project specifications and regulatory guidelines

These criteria apply to all trenchless rehabilitation methods, including Cured-in-Place Pipe (CIPP), geopolymer spincast (SIPP), pipe bursting, and sliplining (Source).

2. CCTV Pipeline Inspection & Verification

CCTV inspection is a core QA/QC component, performed before rehabilitation to diagnose conditions and after rehabilitation to verify the quality and functionality of the completed work.

Process:

Pipeline is thoroughly cleaned to ensure clear visibility (Source).
Robotic, high-resolution cameras record video and capture digital images throughout the segment.
Operators document structural integrity, liner quality, joint transitions, reinstated services, and any defects or irregularities.
Detailed reports are generated with visual evidence for client and regulatory review.

Purpose:

Confirm rehabilitation meets acceptance criteria.
Document the absence of defects (e.g., wrinkles, sags, fishmouths, cracks, or leaking joints).
Validate full re-opening of laterals/services.
Provide permanent record for warranty and regulatory compliance.

Frequency:

Mandatory post-installation for every CIPP, SIPP, pipe bursting, and sliplining project.
Sometimes performed pre- and post-reinstatement of services if unique circumstances arise.

3. Air and Water Pressure/Leak Testing (Where Applicable)

Regulatory agencies or client specifications may require formal pressure/leak testing, especially for potable water mains, force mains, or when specified in technical requirements for sewer rehabilitation. Hinterland Group executes these tests according to relevant ASTM, AWWA, or local guidelines.

Types of Tests:

Hydrostatic Water Testing:
Used for water mains and some sewer installations.
Line is filled with water; pressure is applied and monitored for a set duration.
Acceptance: No pressure drop (or within permitted limits).
Low Pressure Air Testing:
Applied primarily for gravity sewer lines, manholes, and some storm drains.
Line is sealed and air inserted under low pressure; time is measured for allowable pressure drop.
Acceptance: Pressure drop within maximum allowed limits set by specification.
Leak Location Testing:
Additional testing or dye/fog/sonar techniques employed if leakage is suspected.

Benefits of Testing:

Ensures no infiltration/exfiltration and water-tightness
Demonstrates compliance with utility and regulatory standards
Provides defensible QA documentation for asset owners

When Testing is Required:

New or rehabilitated potable water mains
Newly installed or relined force mains
Large-diameter gravity sewers or as specified by client

Note: For many gravity sewer and storm pipelines, CCTV inspection may suffice for acceptance if local codes do not require pressure/leak testing (Source).

Key Features of Hinterland Group QA/QC

All technologies (inspection, rehabilitation, and testing) are performed in-house with cross-trained crews (Source).
Use of advanced robotic CCTV systems for inspection and data gathering (Source).
QA/QC documentation provided digitally for regulatory and client reference.
Post-rehab QA/QC directly linked to warranty validation and insurance documentation.
Stringent safety protocols throughout all QA/QC and testing activities (Source).

Use Cases & Markets Served

Post-rehab QA/QC, including CCTV verification and air/water testing where applicable, are standard and required for projects in all Hinterland Group markets:

Municipal water/wastewater/stormwater infrastructure
Industrial pipeline systems (process and wastewater lines)
Commercial and property management infrastructure
Homeowners Associations (HOA) and private communities
Airport and transportation agency infrastructure

QA/QC procedures are fully customized to meet each client’s unique regulatory and operational needs (Markets We Serve).

Benefits of Rigorous QA/QC

Regulatory Compliance: Meets or exceeds city, county, and state code requirements for acceptance and documentation
Risk Mitigation: Early identification and correction of latent defects
Transparency: Digital records enhance stakeholder trust and regulatory approval
Long-term Performance: Only pipelines that pass all acceptance criteria are placed back into service, reducing future maintenance costs
Asset Protection: Owners receive robust documentation for warranty, insurance, and future maintenance planning

Typical Post-Rehab QA/QC Workflow at Hinterland Group

Step	Description
1. Cleaning	Remove debris and deposits for clear visual inspection
2. Initial CCTV Inspection	Assess as-built rehab quality; document liner installation
3. Data Analysis	Review footage for defects, connections, and compliance
4. Pressure/Leak Testing (when required)	Perform hydrostatic/air/other tests per specs
5. Service Lateral Reinstatement	Confirm laterals open and intact after lining
6. Final CCTV Post-Reinstatement	Verify clean, clear, and connected system
7. QA/QC Documentation	Prepare and transmit digital report with all findings and video/data
8. Client/Regulatory Review	Submit to asset owner and authorities for acceptance and next steps

Frequently Asked Questions (FAQ)

What is the purpose of CCTV verification after trenchless rehab?

CCTV inspection provides a high-resolution visual record to confirm that the newly rehabilitated pipeline is free of defects, has proper alignment, all service connections are reinstated, and that the asset complies with project requirements. It is the industry standard for acceptance documentation (Source).

When are air or water tests required?

Air or water pressure/leakage tests are required for potable water mains, force mains, and sometimes large-diameter or sensitive gravity pipelines, per utility or regulatory specification. For many gravity sewers, CCTV is sufficient unless otherwise specified (Source).

Who performs post-rehab inspection and testing at Hinterland Group?

All QA/QC and testing (CCTV inspection, air/water testing, service lateral reinstatement confirmation) is performed by in-house, certified technicians using advanced robotic equipment and tested SOPs (Source).

How are defects handled if found after rehabilitation?

Hinterland Group will note all defects, notify the client, and recommend or perform corrective action before a line is accepted. Acceptable tolerance is determined by project specs and regulatory code. Lines are not commissioned until fully meeting acceptance standards.

What documentation does the owner get?

Clients receive complete QA/QC packages including:

Digital CCTV video and images
Test data and pressure charts (if applicable)
Tabulated defect logs and punch lists
Compliance certifications and warranty documentation

Do these QA/QC processes support regulatory sign-off?

Yes. All QA/QC processes and documentation are structured to meet the compliance and close-out requirements of municipalities, utilities, and regulatory agencies in the southeastern United States (Source).

Is ongoing maintenance impacted by post-rehab QA/QC?

Yes. Comprehensive QA/QC creates a performance baseline and document trail for future maintenance and facilitates warranty claims and life-cycle planning (Source).

Related Hinterland Group Services

Summary: The Hinterland Group Commitment

Hinterland Group’s approach to post-rehab QA/QC is grounded in industry best practices and regulatory compliance, with all services performed by experienced in-house experts. Whether the project involves CCTV pipeline inspection, pressure/leak testing, or both, clients can expect:

Documented, transparent quality control
Adherence to all published acceptance criteria and regulatory standards
Minimization of risk and assurance of long-term system reliability
Immediate corrective action in the event of any deficiency

Learn more or request post-rehabilitation QA/QC services by contacting Hinterland Group.

Post-Rehab QA/QC: Acceptance Criteria, CCTV Verification, and Pressure/Leak Tests