THE PURPOSE OF THE MANHOLE REHABILITATION PROJECT WAS TO CORRECT (BUT NOT LIMITED TO) THE SERIOUS ISSUES OF INFLOW & INFILTRATION (I&I) THAT CONTRIBUTED TO: SEWER OVERFLOWS, AND THE SIGNIFICANT AMOUNT OF GROUNDWATER & STORM WATER FLOW TO SEWER TREATMENT PLANT (= BEYOND DESIGN CAPABILITY OF THE PLANT). THE I & I ISSUES DEGRADED THE OPERABILITY, RELIABILITY AND AVAILABILITY OF THE SEWER SYSTEM INFRASTRUCTURE. ONE  INDUSTRY STUDY CITED THAT DUE TO I & I, ONLY 30% OF FLOW TO TREATMENT PLANTS IS ACTUALLY SEWER.

SEWER MANHOLE’S CONCRETE DETERIORATION WAS DUE TO MICROBIAL-INDUCED CORROSION, OR MIC. IT IS A PROCESS WHERE AN AEROBIC BACTERIA, FORM IN RAW SEWAGE EFFLUENT AND NATURALLY CREATES HYDROGEN SULFIDE GAS, OR H2S. THE H2S GAS IS THEN METABOLIZED BY AEROBIC BATERIA WHICH CREATE LARGE QUANTIFIES OF SULFURIC ACID IN THE PRESENCE OF OXYGEN. THE SULFURIC ACID IN TURN ATTACKS EXPOSED CONCRETE AND UNPROTECTED SURFACES OF IRON, STEEL AND COPPER, RESULTING IN CORROSION AND DETERIORATION OF THE EXPOSED VULNERABLE MATERIALS.

MADERO’S WARREN EPOXY HAS BEEN SUCCESSFULLY APPLIED OVER MANY THOUSANDS SEWER MANHOLES IN THE PAST THIRTY YEARS AROUND THE WORLD. OUR WARREN EPOXY IS AN APPROVED PRODUCT BY THE CITY OF HOUSTON’S PUBLIC WORKS & ENGINEERING FOR SEWER SYSTEMS REHABILITATIONS. FURTHERMORE, AND DUE TO ITS OUTSTANDING PERFORMANCE AND PROVEN TRACK RECORD, WARREN EPOXY HAS BEEN APPROVED BY MUNICIPALITIES AROUND THE WORLD FOR POTABLE WATER & SEWER SYSTEMS APPLICATIONS. TESTIMONIALS OF SATISFIED CLIENTS CAN BE PROVIDED UPON REQUEST.

Issue Date: Jan. 31st, 2024; Rev. 0

MADERO successfully executed the turnkey task of Corrosion Protection, Impermeabilization, and Structural Rehabilitation of a highly deteriorated concrete infrastructure, in a quality and cost effective manner, no safety issues, and within the agreed work schedule with the customer. This infrastructure was the only discharge channel of the potable water treatment plant for the city’s 380,000 inhabitants, which was built in 1940.

This project was the first world-class rehabilitation of its kind in Latin America by MADERO and the client. This project only allowed three mini-stops with a total project duration of 48 hours. The scope of work was critical path at all times. The project milestones and compressed work schedule was extremely aggressive. There was no room for errors or omissions because the city’s drinking water tanks were of limited capacity, and the municipality could not guarantee the water supply to the inhabitants if the work exceeded the agreed hours.

PRODUCT APPLICATION

The surface preparation was performed with wet sand. During the Engineering Assessment Inspection, a large number of structural cracks, holes and substrate deterioration mechanisms were discovered, including corroded metallic components. A large corner wall area of the canal had significant structural deterioration. MADERO manually rebuilt it with composite materials (Warren Epoxy and Fiberglass). The bulk of the Warren Epoxy coating was spray applied. Localized structural deteriorated areas were manually repaired via trowel method.

CONCLUSION

The Warren Epoxy stopped the significant water leaks that saturated the ground, stopped the sinking of the water treatment facility, and provided structural integrity and impermeabilization to the channel.

This rehabilitation project had a great return on the investment because the project was paid off in nine months. Furthermore, by eliminating the significant water losses, the customer had an immediate and significant increase in water availability and capacity. MADERO’s execution of this turnkey Mission Critical Project was a total success.

The age of each of the elevated Carbon Steel Tank Silos was approximately 25 years old. They stored and operated a hot mix solution of calcium hydroxide and water. Engineering assessment inspections identified many corrosion problems, structural deterioration, and imperfect and irregular welds on the substrate to be coated.

PRODUCT APPLICATION

As part of the surface preparation, high and ultra-high pressure jets of water (Range: 25,000 to 40,000 Psi) were applied to the silo internals for removing deposits of Calcium Hydroxide, which was solidified and strongly adhered to the substrate of the two tanks. Subsequently, a wet sandblasting surface preparation was done to generate the anchoring profile and required cleanliness for applying  the coating. All required structural repairs were performed, including removal of imperfect and irregular welds were removed.  The  Warren Epoxy was sprayed, and the average coating thickness was 1/8” (3 millimeters). Quality Control & Quality Assurance and  inspections were performed and they all passed with outstanding values.

CONCLUSION

The Impermeabilization and Rehabilitation Project of the two silos were successfully executed in ten (10) days, in a quality and cost-effective manner, with no safety issues, and within the agreed work schedule with the customer. During the implementation of the  project, the plant was  able to continue operating at 50% capacity without stopping production. MADERO’s execution of this turnkey  Mission Critical Project was a total success.

Corrosion & Impermeabilization Protection, Structural Rehabilitation/Repair of Semi Deteriorated & Fully Deteriorated Metallic & Concrete Process Piping Systems & Component with Rapid Cure, Smart & Durable Engineered Composite Pipe Repair Systems.

Pics. 1 & 2: Composite Structural Rehab/Repair of Fully Deteriorated 12” Dia. Corroded Pipe w/ Pinholes

Pics. 3 & 4: Composite Structural Rehab/Repair of Fully Deteriorated 14” Dia. Corroded Pipe w/ Pinholes

Pics. 5 & 6: Composite Structural Rehab/Repair of Semi Deteriorated 54” Dia. Corroded Pipe w/ 63% Wall Loss

Corrosion Protection Coating Application at Market Center Lift Station’s Atmospheric (e.g. Valve Rooms) and Immersion (e.g. Wetwell) Piping Systems at City of Terrell, Texas. Per owner’s coating specification, Immersion Piping System required application of three layers of Sherwin Williams Macropoxy coating system (i.e. primer, intermediate, and topcoat). Atmospheric Piping System also  required first two layers of Sherwin Williams’ Macropoxy coating and Polyurethane topcoat. MADEROs Scope Of Work also included Abrasive Surface Preparation with Dustless Sponge Jet Abrasive System, Quality Control Testing (e.g. Wet Gauge, Holiday, and Adhesion Pull) and Quality Assurance.

Using Warren Structural Epoxy for Long Term Useful Operational Life. Asset Owner: City of Fort Worth. The newly Engineered Protective, Structural Rehabilitation & Repair provided full structural integrity plus additional benefits (but not limiting to): 

A. Able to withstand all the applicable structural design basis loads of soil and hydro loads.

B. A durable barrier against potential Inflow / Infiltration (I/I) of groundwater and stormwater, and hydrogen sulfide attack.

C. Pipe flow capacity increase due to Warren Epoxy’s Low Coefficient Of Roughness (COF) Vs. Deteriorated Concrete’s High COF.

The following pictures provide a view of their As-Found & As-Left Conditions of the Rehabilitated/Repaired Structures:

The plant was constructed around 2014. After five years of operation, its concrete and metal structures had accelerated corrosion & structural deterioration due to the surrounding aggressive marine environment, and hydrogen sulfide attack from processing sewer wastewater. Furthermore, in 2017, the sewer structures were coated with an elastomeric protective coating. After two years of service, the coating was fully deteriorated and delaminating. 

In May 2019, MADERO Provided Turnkey Certified Engineering Design / Installation / QA & QC Testing & Inspections of MADERO’s Structural Warren Epoxy Liner on Wastewater Sewer Treatment Tanks (e.g. Clarifier, Aeration Basin, Digester, Chlorine Contact Chambers), Concrete/Brick Manholes, and Metal Pipes & Structural Beams. MADERO also applied Polyurethane Coating in specific atmospheric areas & Performed Inflow & Infiltration (I/I) Structural Repairs.

Major Structural Engineered Rehabilitation & Repair, and Structural Optimization of Fully Deteriorated Stormwater Piping System at Neyland Stadium using Structural Epoxy and High Strength Carbon Reinforced Polymer for Structurally Robust Long Term Useful Operational  Life. Asset Owner: University of Tennessee. The buried Non-Structural Shotcrete Stormwater Piping System segment was located about 60 feet below ground of 100+ years old Neyland Stadium, in Knoxville, Tennessee. The newly Engineered Protective and Structural Composite Piping System provides full structural integrity plus additional benefits (but not limiting to):

a. Able to withstand all the applicable structural design basis loads of soil and hydro loads.

b. High strength Carbon Fiber Reinforced Polymer provides a more robust long-term operating life by protecting the new composite pipe with resistance to creep rupture and fatigue failure. 

c. A durable barrier against potential Inflow / Infiltration (I/I) of groundwater and stormwater.

d. Flow capacity increase due to Warren Epoxy’s Low Coefficient Of Roughness (COF) Vs. Shotcrete’s High COF.

Major Structural Engineered Rehabilitation & Repair, and Structural Optimization of Deteriorated Boston Marginal Conduit (BMC) Tunnel (Height: 12 Ft. / Across: 10 Ft.) using Structural Warren Epoxy and High Strength Carbon Reinforced Polymer for Structurally Robust Long Term Useful Operational Life. Asset Owner: Massachusetts Water Resources Authority (MWRA). BMCs material of construction is Un-Reinforced Concrete, and it is over 100 years old. BMC Tunnel System is Vital & Essential Infrastructure for downtown Boston because it is a major collector of Sewer Wastewater and Stormwater.