[MQP] Responding to Challenges following the Panama Canal Expansion Project

Sponsor: National Science Foundation IRES Grant
Panama Canal Authority
Student Team: Liliana Almonte
Caitlin Burner
Julia Ring
Victoria Simpson
Sonia Zarate
Abstract: The Panama Canal has shaped the global shipping industry since 1914, but recently expanded its operations to respond to increasing world trade. Projects completed in collaboration with the Autoridad del Canal de Panamá over the course of three months in Panama focused on the treatment of potable water originating in the canal and the maintenance of its aging structures following the expansion. Recommendations were provided to aid in preserving the sustainability of the canal.
Links: Final Report

 

Executive Summary

In 1914, the opening of the Panama Canal changed both the global shipping industry and the country of Panama. The Canal Expansion Project, completed in June of 2016, further developed the waterway, making it accessible to new markets. Due to the increasing age of the original structures and the different operational procedures for the third set of locks, new challenges arose that needed to be addressed to preserve the longevity of the system. This report contains the findings of four separate projects related to these challenges.

The Panama Canal Expansion has increased the number of transits and size of ships passing through the new set of locks, thus increasing the inflow of water into Gatún Lake from the Pacific and Atlantic Oceans. As Gatún Lake is a large supplier of potable water to the residents of Panama, the Autoridad del Canal de Panamá (ACP – Panama Canal Authority) has been monitoring its water quality, paying specific attention to salinity. The Analysis of Chemical Consumption Patterns at Miraflores Filtration Plant project entailed collecting and analyzing chemical consumption data and water samples for the fiscal year. The goal of this project was to assess the effect of salinity and other related water quality parameters on water treatment at the Miraflores Filtration Plant before and after the opening of the expansion project. To achieve this goal, an understanding of the plant operations was established; data regarding chemical consumption and water quality parameters were collected; consumption patterns pre- and postexpansion operations were established and the chemicals that had increased in dosing were identified; and potential relationships between water quality parameters and chemical dosing were investigated. Through a combination of statistical analyses, it was found that postexpansion operations have not significantly increased consumption of chlorine or alum. Furthermore, a correlation analysis determined that, across all periods, turbidity levels and volume of influent have a significant, positive relationship with alum consumption, while salinity levels have a significant, positive relationship with chlorine consumption. Finally, it was concluded that post-expansion operations have only impacted salinity levels, and although these have not reached the maximum value permitted for human consumption, a significant increase has occurred since pre-expansion operations. To guarantee that water treatment within the plant continues to be effective, it has been recommended that the monitoring of salinity levels at all seven distribution points continues, a necessary measure to ensure that levels do not surpass the freshwater limit. In addition, the further investigation of the chemical relationship between chlorine consumption and salinity was advised to determine the effectiveness of using chlorine to treat salt concentration. Lastly, an investigation on how seasonal changes affect salinity levels in Gatún Lake was recommended as only salinity data during the rainy season was available for this analysis.

Due to population increase and higher potable water demands, the ACP’s water treatment plants currently operate under different flows than those for which there were originally designed. The Mount Hope Water Filtration Plant, responsible for supplying potable water to the northern region of Panama, is in need of an evaluation of the facility’s efficiency based on differences between particle speeds in the water. The goal of the Process Analysis of Mount Hope Water Filtration Plant project was to analyze the flow of water through specific components of the plant. To achieve this goal, the layout of the plant was analyzed, the velocity gradients were calculated for the rapid mix chamber and flocculation basin, and the detention time was calculated for the sedimentation basin. Based on the current daily discharge of the plant, the calculated velocity gradient in one pathway (of three) of the rapid mixing chamber ranged between 146.69 and 154.81 s-1 , which fell below the recommended ranges of 300 – 1000 s -1 . It was suggested that the dimensions of the structure be reviewed and potentially modified, as volumetric decreases would increase the velocity gradient of the water passing through the chamber, improving the purification at that step. Based on the current shaft rotational velocity of 1.49 rpm, the velocity gradient in the flocculation basin was calculated to be between 6.75 and 7.12 s-1 . It was recommended that a motor be acquired that can operate at a higher rate and across a range of rotational velocities. This would allow operators to achieve a wider range of targeted velocity gradients, responding to the variations in water quality at any given time. Depending on the water volume within the sedimentation basin, the detention time in the structure at the time of analysis was between 83 and 100 min. It was recommended that modifications to the sedimentation basin be considered to increase its volume. A final option would be to consider other types of sedimentation basins, using newer technology.

The water that is processed by the various filtration plants originates in Gatún Lake, an artificial body of water created and maintained by a system of dams and spillways. Inspections are conducted on these structures to ensure that they remain in working order and to identify points of loss before a failure occurs. The ACP implemented a formal, detailed, inspection program in 2015 but encountered unexpected difficulties due to the complexity and age of the structures. The Evaluation of the ACP’s Formal Inspection Program of Dams and Spillways project focused on revising the formal inspection protocol and providing suggestions to further improve their processes. To achieve this goal, the meaning of “formal inspection” in the context of other regions was researched, the ACP’s current inspection process was reviewed, U.S. standards and the ACP protocol were compared, and suggested checklists were created to be followed by the ACP during future inspections. It was concluded that the ACP follows the correct steps to complete a formal inspection; however, their protocol was in need of updating to allow for ease of inspection. Additionally, it was determined that the formatting of prior reports was inconsistent and difficult to navigate. Checklists of items to be inspected were modified to increase the efficiency of the inspections and an outline was created to allow personnel to complete the inspection report in the required 15-day period. Finally, suggestions were provided for the preparation processes of the inspections in order to help ensure the sustainability of the structures being inspected.

Risk analysis is a tool used to increase the productivity of inspection and maintenance programs and can be used to prioritize specific repairs before failures occur. Madden Dam and Spillway is considered to be the most high-risk water retention structure in the Panama Canal System because it operates with drum gates, a design not used in modern construction. The goal of the Risk Analysis of Madden Dam and Spillway Drum Gates project was to improve the current maintenance program and allow for preemptive repair of the drum gates using a riskbased analysis methodology. To achieve this goal, the structural condition of the Madden Spillway drum gates over time was analyzed, maintenance programs aimed at preserving adequate reliability of spillway gates were researched, the capacity of the drum gate’s structural components were calculated and compared to their demand, and suggestions were made to improve the current maintenance program. After reviewing historical inspection and maintenance reports from 1982 to 2015, a historical maintenance log was created to record the structural condition of each drum gate. The upstream and bottom skin plates were considered the most critical elements because they experience direct water pressure from Alhajuela Lake and the flotation chamber, respectively, and were analyzed further. The stress acting on the upstream plate was calculated to be 14.9 ksi (102.7 MPa), while the stress on the bottom plate was found to be 10.1 ksi (69.6 MPa). The allowable stress, or capacity, was evaluated to be 19.8 ksi (136.5 MPa). The critical thickness of each plate was calculated, assuming capacity was equal to demand, and given a factor of safety in order to provide a warning indicator for the ACP to begin planning repairs or replacements. While it was concluded that the drum gates remain in good condition, recommendations were presented for updating the maintenance log annually, improving inspection records, and conducting a risk analysis based on thickness of the plates over time.

These projects were completed over the course of three months in collaboration with ACP engineers and the support of WPI faculty. Background knowledge from previous coursework, experience from prior internships, information gathered from extensive research, lab work, and field visits came together to make this work possible. Based on the results, suggestions were provided to the ACP in hopes of improving the projects’ respective systems