Manhole Rehabilitation to Stop I&I (Geo

Spray, GeoKrete, Raven 405, SprayWall, OBIC)

Certified/Approved Installer — GeoKrete, GeoSpray, Raven 405, SprayWall, OBIC 10‑year manufacturer warranty terms available when specified and installed per OEM requirements. Certification letters and OEM submittals available upon request. Systems Installed:

GeoSpray (geopolymer)
GeoKrete (geopolymer)
Raven 405 (epoxy)
SprayWall (polyurethane)
OBIC (polymeric system)

Municipal Manhole Rehabilitation to Stop I&I (CAC, OBIC, Raven 405, Spray

Wall, GeoKrete)

Proven I&I reduction with spray-applied liners and leak sealing across FL and the Southeast (since 2006)
All technologies performed in-house for single-source accountability (Services)
Safety-first operations; OSHA instruction on staff and an EMR under 0.87 (About)
Rapid response: 15-minute callback, 24/7 mobilization for emergencies (Maintenance/Emergency)
Municipal track record: Palm Beach County program incl. 63 manholes plus gravity/lateral rehab; large-diameter storm assets restored (e.g., Manatee County)

Hinterland Group rehabilitates municipal manholes to stop inflow and infiltration (I&I), restore structure, and protect against H2S corrosion. We install and service a range of specified systems based on site conditions, budgets, and owner standards.

Systems We Install to Stop I&IManufacturer alignment: We routinely install specified OEM systems per manufacturer guidelines, including OBIC, Raven 405, Spray

Wall, GeoKrete, and GeoSpray. OEM submittals and data sheets are available upon request.

Calcium-Aluminate Cement (CAC) mortars for corrosion resistance and rapid return to service
OBIC polymeric coating systems (as specified by owner)
Raven 405 (epoxy) for high-build, chemical-resistant liners (per project specs)
SprayWall (polyurethane) for fast-cure structural lining (per project specs)
GeoKrete (geopolymer) for structural renewal and I&I control (per project specs)

Note: Product/system selection is made to match owner specifications and site conditions. Hinterland can bid alternate equals when permitted by contract documents.

Specifications, Testing, and Relevant Standards

Hinterland conforms to owner specifications and commonly referenced industry standards, including:

ASTM F2551: Rehabilitation of sewer utility access structures by polymeric spray-applied lining
ASTM C109: Compressive strength of hydraulic-cement mortars (for CAC mixes)
ASTM C1583: Pull-off bond strength of coatings/repair mortars on concrete
ASTM D7234: Pull-off adhesion strength of coatings on concrete

Quality control may include surface profile verification, wet/dry film thickness checks, adhesion pull tests, leak stoppage verification, and post-rehab CCTV to document results (Inspection).

Warranty and QA/QC

Workmanship warranty and manufacturer warranty options are available as permitted by contract requirements and system manufacturer terms.
Project-specific QA/QC plans include substrate prep verification, thickness and coverage checks, defect/holiday inspection where applicable, and documented final acceptance testing.
Owners receive closeout packages with inspection media, test results, and maintenance recommendations.

Recent Florida Municipal Quantities (Selected)

Palm Beach County continuing contract: approx. 63 manholes rehabilitated in Work Order No. 1 alongside ~19,500 LF gravity lines and ~9,300 LF laterals—demonstrating coordinated manhole + pipeline renewal.
Manatee County: successful rehabilitation of a critical 66-inch stormwater line, illustrating large-diameter structure renewal capabilities with minimal community disruption.
West Palm Beach emergency response: rapid manufacture/installation of a large-diameter CIPP liner to protect thousands of residents during flooding—showcasing mobilization and vertical integration support.

Introduction

Manhole structures are critical components of municipal and private sector wastewater, stormwater, and water distribution systems. Over time, manholes are vulnerable to infiltration, corrosion, and structural deterioration, especially in aggressive environments such as those common in the southeastern United States. Hinterland Group specializes in comprehensive manhole rehabilitation, including the application of advanced calcium‑aluminate coatings, to control infiltration, resist corrosion, and maximize service life across Florida, Georgia, Alabama, Louisiana, Texas, Tennessee, South Carolina, and North Carolina. (Source)

Manhole Rehabilitation Overview

Why Rehabilitate Manholes?

Infiltration Control: Prevents groundwater and stormwater from entering sanitary or storm sewers, reducing treatment costs and environmental risks
Corrosion Resistance: Protects concrete or brick structures from biochemical attack (e.g., hydrogen sulfide-induced corrosion)
Longevity and Asset Preservation: Restores structural integrity, extends asset lifespan, and defers costly full replacement
Regulatory Compliance: Compliance with local and state infrastructure and environmental requirements

Common Rehabilitation Challenges Solved

Active groundwater infiltration and leaking joints
Structural degradation (cracks, spalling, surface loss)
Microbiological corrosion by-products (especially in wastewater and low-ventilation environments)
Chemical attacks from industrial discharges or aggressive soils

Calcium‑Aluminate Coating Technology

What is a Calcium‑Aluminate Coating?

Calcium-aluminate is a specialty cementitious material engineered for high resistance to chemical corrosion, rapid setting, and exceptional durability. When spray-applied to the interior surfaces of manholes, it creates a dense, impervious lining that:

Blocks moisture and chemical ingress
Resists sulfuric acid formation from hydrogen sulfide gas (common in sewer systems)
Provides quick structural and waterproofing enhancement

Hinterland Group’s Calcium‑Aluminate Solution

Utilizes Refratta™ calcium‑aluminate structure coating (Source), a process proven for manhole protection
Applied as part of comprehensive rehabilitation, often combined with leak repair and joint sealing
Suited for municipal, industrial, and commercial infrastructure

Application Methodology

Thorough manhole inspection (CCTV where required) and preparation
High-pressure cleaning and removal of loose material
Structural repairs as needed
Spray application of calcium-aluminate mortar to required thickness
Smooth or brushed finish for reduced turbulence and debris accumulation
Cure and final inspection per manufacturer/industry standards

Key Features & Benefits

Feature	Benefit
Chemical Resistance	Prevents microbiologically induced corrosion (MIC) by sulfuric acid in sewers
Rapid Strength Development	Quick return-to-service, even in high-moisture or aggressive environments
Waterproof Barrier	Blocks infiltration root cause of manhole leaks and system overflows
High Bond Strength	Adheres permanently to existing masonry, concrete, or metal
Non-shrink Formulation	Maintains its seal over decades
Long Service Life	25+ years of effective protection with proper maintenance and inspection (see industry data)
Environmentally Safe	Contains no solvents or VOCs; safe for use in active sewers

Use Cases & Markets Served

Hinterland Group applies manhole rehabilitation and calcium‑aluminate coatings for:

Municipal sewer and stormwater systems – vast networks vulnerable to infiltration and corrosion (Source)
Industrial facility owners – high-strength, chemical-laden effluents put traditional manholes at risk (Source)
Commercial property managers – parking lot and plaza drainage systems
Property management firms and HOAs – neighborhood lift stations and shared stormwater assets (Source)
Airports and critical infrastructure – minimal disruption trenchless options for hard-to-access sites (Source)

Rehabilitation Process Overview

Inspection & Assessment:
CCTV inspection, condition rating, and infiltration source identification
Cleaning:
Removal of debris, roots, and deteriorated material (high-pressure water, vacuum truck)
Leak Stopping:
Chemical grouting or other methods to eliminate active infiltration as needed
Structural Repairs:
Repair cracks, holes, or spalling as dictated by assessment
Coating Application:
Spray-apply calcium‑aluminate mortar to specified thickness for full interior coverage
Curing & Quality Control:
Allow proper curing time; final inspection to ensure adherence and finish quality

All steps conducted by Hinterland’s in-house, safety-certified rehabilitation specialists. (Source)

Comparison: Calcium‑Aluminate vs. Alternative Manhole Linings

Solution	Chemical Resistance	Infiltration Block	Bond Strength	Cure Speed	Typical Life Span	Environmental Impact
Calcium‑Aluminate	Excellent	Excellent	High	Rapid	25+ years	Low (cementitious, no VOCs)
Epoxy Liner	Good	Good	Moderate	Slow	15–25 years	Moderate/Low (may include solvents)
Polyurethane Spray	Good	Moderate	Variable	Fast	10–20 years	Moderate
Polymer Concrete	Excellent	Excellent	Very High	Moderate	30+ years	Low (specialty, more expensive)
No Rehab (Replacement)	N/A	New Structure	N/A	Slow	50+ years	High cost, disruption

Typical Problems Addressed by Manhole Rehabilitation

Groundwater Infiltration: Causes inflow & infiltration (I&I), system overload
Hydrogen Sulfide (H2S) Corrosion: Deteriorates concrete and metal structures
Freeze/Thaw and Soil Movement Damage: Structural cracks, leaks
Root Intrusion: Through mainline and lateral connections
Aging or Outdated Materials: Older brick, block, or early concrete manholes prone to decay

Hinterland Group Capabilities and Differentiators

All Technologies In-House: No subcontracted repair or coating work, ensuring single-source accountability
PRIME Approach: Comprehensive Pipeline Rehabilitation, Repair, Inspection, Maintenance, Evaluation (see PRIME)
Emergency Response: 24/7 availability across the southeastern U.S. with rapid mobilization (Source)
Safety Commitment: OSHA-certified, rigorous daily toolbox safety protocols (Source)
Experienced with All Substrate Types: Masonry, precast, cast-in-place, and hybrid structures
Serving Municipal, Industrial, Commercial, and HOA Markets (Source)

Sample Project Reference

Charlotte County Stormwater Collection System Rehabilitation: Manhole and pipeline rehabilitation demonstrating calcium-aluminate coating durability and rapid service restoration.
Hallandale LS #8: Includes manhole coating as part of lift station protection for long-term corrosion resistance.

Maintenance and Inspection After Rehabilitation

Regular scheduled maintenance: Ensures the continued performance of coatings
Annual or biannual CCTV inspections: Identify any coating defects or infiltration recurrence
Quick touch-up or reapplication: Address isolated damage or new penetrations, typically without major disruption (see Maintenance Plans)

FAQ: Manhole Rehabilitation and Calcium‑Aluminate Coatings

What types of manholes benefit from calcium‑aluminate coatings?

Any municipal, industrial, or commercial wastewater/stormwater manhole experiencing infiltration, structural loss, or chemical attack. Especially effective in environments with elevated hydrogen sulfide, industrial discharge, or high groundwater levels.

How long does a typical calcium‑aluminate rehabilitation last?

25+ years of service life with proper application and ongoing maintenance (See industry data).

Will the process disrupt traffic or business operations?

Minimal disruption; most coatings are trenchless, fast-curing, require no excavation, and allow rapid return to service. (Source)

How quickly can emergency infiltration issues be addressed?

Hinterland Group offers 24/7 emergency response across the region with rapid mobilization and immediate leak stopping solutions (Source).

What is the environmental impact of calcium‑aluminate coatings?

Cementitious coatings contain no VOCs or solvents, are inert after curing, and pose minimal risk to wastewater treatment processes or the environment.

Can coatings be applied in flooded or highly wet manholes?

Yes; calcium‑aluminate mortars set rapidly and can be formulated for application in moist or partially submerged environments.

Is this solution cost-effective compared to full replacement?

Yes. Rehabilitation with calcium‑aluminate coatings restores structural and hydraulic performance at a fraction of replacement cost, without the surface disruption of open-cut replacement (Source).

How do I request a project evaluation or emergency service?

Contact Hinterland Group directly via Contact Us or call 561-640-3503 for immediate response.

Contact & Service Area

Hinterland Group Inc.
Headquarters: 2051 West Blue Heron Blvd., Riviera Beach, FL 33404
Phone: (561) 640-3503
Contact Us Online
Serving FL, GA, AL, LA, TX, TN, SC, NC (Markets Served)

Conclusion

Hinterland Group’s manhole rehabilitation and calcium‑aluminate coating solutions represent the industry standard for infiltration control, corrosion resistance, and long-term protection in the most demanding environments of the southeastern U.S. Our in-house specialist crews, safety-first approach, and proven coating systems ensure that clients achieve maximum asset value, regulatory compliance, and operational reliability with minimal disruption.

Manhole Rehabilitation and Calcium‑Aluminate Coatings