Irrigation Canals Research Articles

An integrated approach to evaluating water contaminants and evaporation in agricultural water distribution systems

This study presents an innovative approach for assessing water quality in agricultural irrigation networks, integrating stable isotope analysis, in vivo zebrafish screening, and comprehensive chemical profiling to investigate the occurrence, transformation, and potential toxicity of organic contaminants. Stable isotope analysis was used to measure evaporation as a proxy for water residence time in the canal, while liquid chromatography-high resolution mass spectrometry (LC-HRMS) identified a range of organic compounds in water samples collected from both the irrigation canal and its source river. Results indicated a reduction in contaminant levels in the canal compared to the river, with the most significant evaporation and concentration changes occurring at a holding reservoir, suggesting that managing residence time could help reduce water loss in arid irrigation networks. The data also highlighted how evaporation, particularly during the dry, hot season, influences contaminant dynamics. Hierarchical clustering of LC-HRMS results showed notable differences between the chemical profiles of canal and river samples, indicating that irrigation systems may contribute to the degradation or removal of certain compounds. Over 60 % of detected compounds were naturally derived, with anthropogenic contaminants like pesticides and personal care products further highlighting human impacts. Priority contaminants, including DEET and 2-naphthalene sulfonic acid, likely originated from urban activities upstream. Initial screening using zebrafish embryos showed bioactivity across sites, confirming the presence of contaminants needing further examination. Correlation analysis linked natural compounds to evaporation rates, suggesting that flora and fauna play significant roles in the chemical makeup of canal water. Overall, this approach provides a comprehensive framework for monitoring irrigation water, offering insights into contaminant behavior and supporting the development of standardized methods for assessing chemical fate and ecological risks in agricultural irrigation systems.

Addressing underestimation of waterborne disease risks due to fecal indicator bacteria bound in aggregates.

This study aims to identify and address significant limitations in current culture-based regulatory methods used for monitoring microbiological water quality. Specifically, these methods' inability to distinguish between planktonic forms and aggregates containing higher bacterial loads and associated pathogens may lead to a severe underestimation of exposure risks, with critical public health implications. We employed a novel methodology combining size fractionation with ALERT, an automated rapid method for comprehensive quantification of culturable fecal indicator bacteria (FIB). Our findings reveal a substantial and widespread presence of aggregate-bound indicator bacteria across various water matrices and geographical locations. Comprehensive bacterial counts consistently exceeded those obtained by traditional methods by significant multiples, such as an average of 3.4×at the Seine River 2024 Olympic venue, and occasionally up to 100×in irrigation canals and wastewater plant effluent. These results, supported by microscopic and molecular analyses, underscore a systematic bias in global water safety regulatory frameworks. Our research demonstrates the inadequacy of traditional culture-based techniques in assessing microbiological risks posed by aggregate-bound FIB and associated pathogens, particularly in water matrices affected by FIB-rich fecal particles from recent sewer overflows or sediment, which can carry higher infectious risks. Incorporating comprehensive FIB analysis techniques, including molecular methods and rapid culture-based approaches as shown in this study, offers a promising and effective solution to these risk assessment limitations.

Prevalence of human Schistosoma mansoni infection in endemic regions (2010–2024): a systematic review and meta-analysis

Schistosoma mansoni infection poses a substantial public health challenge globally, and the World Health Organization (WHO) aims for the elimination of schistosomiasis by 2030. This study aimed to assess the current prevalence of human S.mansoni infection in endemic regions worldwide between 2010 and2024. We conducted a comprehensive search in PubMed/Medline and Scopus databases as well as other public sources from 1 January 2010 to 15 July 2024. Population-based studies reporting the prevalence of S.mansoni infection were eligible. We undertook a random-effects meta-analysis to estimate pooled prevalences with 95% confidence intervals (CIs) in WHO-defined regions and assessed potential risk factors associated with S.mansoni infection. The protocol for this study was registered on PROSPERO (CRD42023438455). We identified a total of 542 eligible studies involving 1,163,866 individuals who had been tested for S.mansoni infection in 38 countries. The overall, pooled global prevalence of S.mansoni infection in endemic region was 14.8% (95% CI, 13.5%-16.1%). The pooled prevalences (95% CI) in specific regions were: 15.3% (13.9-16.8%) in sub-Saharan Africa, 12.4% (8.9-16.4%) in South America and 9.5% (5.4-14.6%) in the Eastern Mediterranean region. There was a 52.6% decrease in prevalence of S.mansoni infection and a 37% decrease in high-intensity infection for studies conducted between 2010 and 2014 compared to those conducted between 2020 and 2023. The present analysis revealed that factors including male gender, bathing or swimming in natural water bodies, crossing rivers or lakes, and engaging in water irrigation activities such as fishing, working in rice paddies or maintaining irrigation canals were significantly associated with S.mansoni infection. The findings of this investigation revealed that, despite a decline in prevalence and high-intensity infection, 7-12% of people in endemic regions, notably in sub-Saharan Africa, remained affected by schistosomiasis mansoni between 2020 and 2024. This study provides data of relevance to policymakers to support efforts to eliminate this disease. This study received no funding.

Trihalomethanes (THMs) formation in chlorine-treated and -untreated wastewater and its horizontal and vertical distribution through the irrigation of agricultural fields

ABSTRACT This study examines the formation of trihalomethanes (THMs) in wastewater intended for crop irrigation. The presence of dissolved organic carbon (DOC) in the water and its release from the soil make it crucial to understand the relationship between THM formation, DOC aromaticity, and residual chlorine. The research takes a dual approach: assessing spatial distribution through field samples from canals now distributing treated, chlorinated wastewater and analysing vertical percolation of irrigation wastewater through soil previously irrigated with untreated, non-chlorinated water for over 100 years. Spatial analysis reveals that THMs are present in wastewater before treatment, with concentrations increasing post-treatment. Although DOC levels decrease after treatment, their aromaticity remains unchanged, suggesting the persistence of labile DOC. The presence of THMs in treated wastewater from irrigation canals may result from shorter travel distances or increased chlorine use during the COVID-19 pandemic. Vertical soil column experiments indicate a correlation between THM generation, water source, and soil type. Results show that THMs are retained in the soil, where labile DOC is trapped, reducing its concentration while potentially releasing DOC from humic substances. Despite this, THM concentrations do not pose a risk to aquifers, though ongoing monitoring is important should soil and/or treatment methods be altered.

Extraction of Canal Distribution Information Based on UAV Remote Sensing System and Object-Oriented Method

At present, the extraction of irrigation canal network distribution information is of great significance for developing a digital twin irrigation district. However, due to the low resolution of remote sensing images, it is difficult to effectively identify the canal networks, especially for channels with a width of less than 1 m, where recognition is insufficient. Therefore, the purpose of this study is to extract canal networks of different widths in an irrigation district in Shaanxi Province as the research area. A rule-based object-oriented classification method was employed, utilizing image data collected by the DJI Mavic 3 multispectral UAV (Unmanned Aerial Vehicle) to explore the accuracy of this method in extracting canal distribution information. Based on UAV multispectral remote sensing imagery, the segmentation parameters for the remote sensing imagery were determined using ENVI 5.6 software, with the segmentation threshold set at 60 and the merging threshold set at 80. By combining the spectral and spatial differences between the canals and other ground objects, rules for extracting canal network distribution information were established, and the information on the distribution of channels in this irrigation area was finally obtained. The experimental results showed a maximum recall rate of 91.88% and a maximum precision rate of 57.59%. The overall recall precision rates for the irrigation district were 85.74% and 55.08%, respectively. This method provides a new solution for identifying and extracting canal systems in irrigation districts, offering valuable insights for acquiring canal distribution information and providing a scientific basis for precision irrigation.

Description of Pegethrix niliensis sp. nov., a Novel Cyanobacterium from the Nile River Basin, Egypt: A Polyphasic Analysis and Comparative Study of Related Genera in the Oculatellales Order.

In this paper, we examine the filamentous cyanobacterial strain NILCB16 and describe it as a new species within the genus Pegethrix. The original population was sampled from a mat growing in an irrigation canal in the Nile River, Egypt. Initially classified under Plectonema or Planktolyngbya, the strain is a potential producer of the toxins microcystin and β-N-Methylamino-L-Alanine (BMAA). Additionally, we reviewed the taxonomic relationships between the Oculatellales genera. To describe the new species, we conducted a polyphasic study, encompassing 16S rRNA gene phylogenetic analyses performed using both Maximum Likelihood and Bayesian methods, sequence identity (p-distance) analysis, 16S-23S ITS secondary structures, and morphological and habitat comparisons. The phylogenetic analysis revealed that strain NILCB16 clustered within the Pegethrix clade with strong phylogenetic support, but in a distinct position from other species in the genus. The strain shared a maximum 16S rRNA gene identity of 97.3% with P. qiandaoensis and 96.1% with the type species, P. bostrychoides. Morphologically, NILCB16 can be differentiated from other species in the genus by its lack of false branching. Our phylogenetic analyses also show that Pegethrix, Cartusia, Elainella, and Maricoleus are clustered with strong phylogenetic support. They exhibit high 16S rRNA gene identity and are morphologically indistinguishable, suggesting they could potentially be merged into a single genus in the future.

Domestic and irrigation water quality on the southern slopes of Mount Kilimanjaro

This study assessed the water quality for drinking and irrigation purposes on the southern slopes of Mt. Kilimanjaro during the dry season under low flow conditions. Fifty-one samples covering eight different water sources (i.e., stream water from natural and anthropogenic impacted streams, domestic water, spring water, rainfall, groundwater, lake water and water from irrigation canals) were collected in a snapshot sampling campaign over 10 days in February 2023. First, physical, chemical and biological parameters were analysed and compared with Tanzanian and international drinking and irrigation water quality requirements. The samples were then ranked according to their suitability for drinking and/or irrigation using water quality indices (WQI). All drinking water quality parameters except for E. coli and turbidity were within the permissible limits. A generalised problem of faecal contamination was found in the study area, including in domestic water, highlighting the need to identify sources of contamination and remediate them before distribution. The drinking water quality index (DWQI) classified 89% of the samples as unsuitable and 11% as excellent for drinking. Irrigation water quality parameters were within the guidelines of restriction of use except for pH in 5 samples. In contrast to the DWQI, the vast majority of the water samples (88%) can be used for irrigation without restrictions according to the irrigation water quality index (IWQI). The suitability of water for irrigation was also assessed using three indices, i.e., Kelley’s Index, Soluble Sodium Percentage and Magnesium Ratio, which indicated potential problems with excess of sodium (about 30% of the samples) and magnesium (about 20%). Further studies combining suitability indices, soil characteristics and crop types are recommended to assess water quality for irrigation use.

Analisis Indeks Kinerja Jaringan Saluran Irigasi Studi Kasus Irigasi Sungai Siulak Deras Kabupaten Kerinci

The Siulak Deras Irrigation canal network is the main source of water distribution in several areas. The Siulak Deras Irrigation Area in Kerinci Regency was built in 1993 with water flow regulation and complete Siulak Deras Irrigation network facilities including the Technical irrigation group. As time goes by, the service function of the irrigation network experiences a decline in performance, so that operation and maintenance of the irrigation network is an activity that is really needed to make the irrigation network remain optimal and maintain its performance. In this regard, an assessment of the Performance Index of the irrigation system in the Siulak Deras Irrigation Area needs to be carried out to determine the value of aspects or components that are not yet optimal in this irrigation area so that special treatment can be immediately carried out or improved. The assessment is carried out by starting an inventory of the condition and function of the physical infrastructure of the irrigation network, planting productivity results, supporting facilities, organization, documentation and institutional P3A to determine the performance value and recommendations for handling it. The results of the irrigation network system performance index in the Siulak Deras irrigation area for the Left Irrigation Channel section are 69.59%, which means that the irrigation system performance is close to good performance, namely 70%, but still needs to be improved and needs attention. With a physical infrastructure value of 29.32%, planting productivity 14.21%, supporting facilities 6.15%, personnel organization 10.94%, documentation 2.46%, and P3A institutions 6.50%. Based on the performance index value obtained, and the total performance score in the form of a percentage, it is necessary to specifically maintain and repair physical facilities and infrastructure at several points that are damaged, facilitate supporting facilities for OP officers so that officers can act quickly and precisely in carrying out activities, and paying more attention to P3A so that it can always contribute to maintaining and utilizing the Siulak Deras irrigation network properly and optimally in the future.

Utility of Certain AI Models in Climate-Induced Disasters

To address the current challenge of climate change at the local and global levels, this article discusses a few important water resources engineering topics, such as estimating the energy dissipation of flowing waters over hilly areas through the provision of regulated stepped channels, predicting the removal of silt deposition in the irrigation canal, and predicting groundwater level. Artificial intelligence (AI) in water resource engineering is now one of the most active study topics. As a result, multiple AI tools such as Random Forest (RF), Random Tree (RT), M5P (M5 model trees), M5Rules, Feed-Forward Neural Networks (FFNNs), Gradient Boosting Machine (GBM), Adaptive Boosting (AdaBoost), and Support Vector Machines kernel-based model (SVM-Pearson VII Universal Kernel, Radial Basis Function) are tested in the present study using various combinations of datasets. However, in various circumstances, including predicting energy dissipation of stepped channels and silt deposition in rivers, AI techniques outperformed the traditional approach in the literature. Out of all the models, the GBM model performed better than other AI tools in both the field of energy dissipation of stepped channels with a coefficient of determination (R2) of 0.998, root mean square error (RMSE) of 0.00182, and mean absolute error (MAE) of 0.0016 and sediment trapping efficiency of vortex tube ejector with an R2 of 0.997, RMSE of 0.769, and MAE of 0.531 during testing. On the other hand, the AI technique could not adequately understand the diversity in groundwater level datasets using field data from various stations. According to the current study, the AI tool works well in some fields of water resource engineering, but it has difficulty in other domains in capturing the diversity of datasets.

Оперативное диспетчерское управление водораспределением в оросительных системах по расчетному приращению объемов

Goal: to improve the methodological approach to developing an algorithm for operational dis-patch control of water distribution based on the calculated increment of water volumes in irri-gation canals. Materials and methods: the dispatch control methodology is described, which is based on the typification of flow conditions between two partitioning structures in technical and functional directions, as well as on the development of systems for unifying channels and their modes using similarity theory methods, which are widely used in hydromechanics and hydraulics. The basis for the implementation of the similarity theory is the principle of using similarity numbers, that is, combinations of dimensionless parameters that determine the char-acteristics of the unsteady motion of a heavy, incompressible, viscous fluid in channels. Re-sults: the general tasks of the dispatcher were determined to re-regulate the hydraulic regime of sections of the irrigation system, without tying them to specific types of hydraulic struc-tures. The main provisions of the method of dispatch control of water distribution based on the calculated increment of volumes, determination of the time of re-regulation between the main and compensating processes of re-regulation are substantiated. Four types of situations are identified when solving dispatch problems of water distribution, which are determined by comparing the volumes and flow rates installed on the site, for each of which the inherent re-regulation order is determined. Conclusion: the article outlines a new methodological ap-proach that ensures the joint use of the method of similarity theory and a simulation experi-ment with the Saint-Venant equations for steady and unsteady water flow in the canals of ir-rigation systems, to solve problems of operational dispatch control of water distribution ac-cording to the calculated increment of volumes.

Implementation of a GIS for the Conservation of Irrigation Canals: Using ArcGIS and Python for Automation

Implementation of a GIS for the Conservation of Irrigation Canals: Using ArcGIS and Python for Automation

Status of Construction Safety in Local Road Bridge Construction and its Consequences in Project Implementation: A Study in Gandaki Province, Nepal

After federalization of Nepal, bridge construction in local roads by provincial levels is in increasing trend. Being highly technical and of risky nature, construction safety needs to be ensured in bridge construction. However, in countries like Nepal, safety issues are considered, with follow up measures, only after the accidents occur at construction sites. In this context, this study aims to assess the present status and consequences of construction safety in local roads bridge project implementation and explore some improvements measures. A quantitative descriptive design was adopted for the study and 30 completed bridge samples from Gandaki province were selected using convenience sampling. Data were collected using questionnaire survey with 56 participants directly related to bridge construction and policy implementation. This study revealed that most of the bridge construction sites have poor workplace safety and worker’s welfare, inadequate provision and use of PPE, lack of trainings and awareness to workers as well as the absence of safety plans and method statements. Similarly, provisions for unsafe supports, shoring, formworks, concreting, and demolition were not noticed. While the absence of safety supervisor, job safety analysis, recording and reporting accident and diseases was observed, abundant cases were found where less importance was given to construction safety and use of PPE undermining the engineering and administrative hazard control methods in road bridge construction. Slip/trip/low falls, hand/leg/head injury, falling from height, eye problem, injury during erections, vehicle and electric current, cost and time overrun, substandard quality, reduced workers’ productivity, increased workers turnover, low construction safety reputation of contractor, loss/damage of land, irrigation canal, drinking water scheme, dust/noise have been found as consequences of poor safety practices. This clearly indicates that present bridge construction safety practices are inadequate and need substantial improvements for better project implementation. The major areas of improvements include safety as first priority, willingness, awareness and commitment of management, contractor and worker, selection of competent workers, formulation of specific safety rules, regulations, codes and their strict enforcement, good communication, safety training and inspection, motivation, adequate budget provision in contract for safety, provision of PPE, feeling safety as self-responsibility and use of technologies as well.

A new invasive freshwater mussel: Discovery of a non-native population of Pilsbryoconcha exilis (Lea, 1838) in Myanmar (Bivalvia: Unionidae)

The present study reports on the first record of a non-native population of the freshwater mussel Pilsbryoconcha exilis (Lea, 1838) (Bivalvia: Unionidae) in Myanmar. It was discovered from irrigation canals that are situated in the Delta Region of the Ayeyarwady River. Based on approximate age estimates and information from local villagers, this population was probably established in 2019-2020. The DNA sequence data reveals that the Ayeyarwady population shares a single COI haplotype and that this haplotype was previously recorded from the Udon Thani Province of Thailand (Mekong River drainage). Based on this evidence, we could assume that P. exilis was introduced to Myanmar from Thailand. Our new findings expand the global checklist of invasive freshwater mussels that currently contains 17 species.

Uncertainty Analysis of Irrigation Canals Operation

Uncertainty Analysis of Irrigation Canals Operation

Chemical Control of Snail Vectors as an Integrated Part of a Strategy for the Elimination of Schistosomiasis-A Review of the State of Knowledge and Future Needs.

WHO promotes the implementation of a comprehensive strategy to control and eliminate schistosomiasis through preventive chemotherapy, snail control, clean water supply, improved sanitation, behaviour change interventions, and environmental management. The transmission of schistosomiasis involves infected definitive hosts (humans or animals) excreting eggs that hatch (miracidia), which infect freshwater snail vectors (also referred to as intermediate snail hosts) living in marshlands, ponds, lakes, rivers, or irrigation canals. Infective larvae (cercariae) develop within the snail, which, when released, may infect humans and/or animals in contact with the water. Snail control aims to interrupt the transmission cycle of the disease by removing the vector snails and, by so doing, indirectly improves the impact of the preventive chemotherapy by reducing reinfection. Snail control was, for many years, the only strategy for the prevention of schistosomiasis before preventive chemotherapy became the primary intervention. Snails can be controlled through various methods: environmental control, biological control, and chemical control. The chemical control of snails has proven to be the most effective method to interrupt the transmission of schistosomiasis. The current review aims to describe the vector snails of human schistosomiasis, present the chemicals and strategies for the control of snails, the challenges with the implementation, and the future needs. Snail control can play a key role in reducing schistosomiasis transmission and, thus, complements other interventions for disease control. There is a need to develop new molluscicide products or new formulations and methods of applications for existing molluscicides that would target snail vectors more specifically.

Impact of lining of irrigation canals on groundwater recharge: A case study from Punjab province in Indus River basin of Pakistan

The Canal irrigation network of Pakistan's Indus River Basin (IRB) is one of the world's largest gravity-flow networks, with a significant portion located in Punjab province. The conveyance, delivery, and application of this water to the irrigated crops in the basin result in the loss of more than 50% of its water. This loss of water from the irrigation system is a major source of recharge for the large alluvial aquifer underlying the IRB. Canal lining is carried out as a measure to reduce seepage losses from the conveyance system of irrigation water. On the other hand, canal lining is considered a barrier to aquifer recharge. A study titled “Impact assessment of canal lining in Punjab,” funded by JICA, has been carried out in order to interrogate the comparative performance of lined and unlined canals and their impact on groundwater recharge. We measured seepage losses from 14 selected irrigation-lined canals in Punjab province under actual field conditions using ponding and/or inflow-outflow methods. Results have been compared with pre-lining seepage rates. The results indicate that canal lining has reduced seepage losses by 78%. The heavy pumping in fresh groundwater areas invites saline groundwater from adjacent saline zones. The canal flows at the head have reduced the recharge to groundwater by 9%. Nonetheless, saving from seepage losses by canal lining has increased available water for crops, but it has decreased groundwater recharge.

Linking recharge water sources to groundwater composition in the Hindon subbasin of the Ganges River, India

Groundwater resources of the densely populated Indo-Gangetic Basin are under increasing pressure, not only from extensive groundwater abstraction, but also from contamination. In this study we aim to better understand how different recharge sources affect the hydrochemical and isotope composition of groundwater. We used the Hindon subbasin in Northern India as a case study. Recharge water sources and groundwater were analysed for hydrochemical variables and stable isotopes along a 50 km transect between the Yamuna and Ganges rivers. Groundwater samples were statistically clustered based on hydrochemical variables, and the spatial variation of the groundwater clusters was compared with recharge sources.Groundwater quality could be linked to both recharge from irrigation canal water as well as recharge from polluted river water of the Hindon and its tributaries. We could not directly link groundwater outside these related zones to their recharge source. However, we suspect that shallow polluted groundwater (< 40 m depth) is affected by recharge from agricultural areas and infiltration of municipal wastewater, whereas deeper unpolluted groundwater (40–80 m depth) originates from recharge by rain and river water under more pristine conditions. Our findings show that human activities significantly impact the quality of groundwater, as we found vertical recharge of clean irrigation canal water and polluted municipal, agricultural and river surface water (up to 40 m depth). At one location, groundwater at 75 m depth shows increased Cl, NO3 and SO4 concentrations, suggesting accelerated downward displacement of polluted shallow groundwater by pumping. Limited horizontal displacement was found. We present a conceptual model demonstrating the evolution from a previously unpolluted groundwater system discharging to the river, to a contemporary system with infiltration dominance of polluted river, municipal and agricultural water and local clean irrigation canal water. This model may be relevant for large parts of the Indo-Gangetic Basin.

Research progress on operation control and optimal scheduling of irrigation canal systems

AbstractOpen canals are a common water transfer method used in water transfer projects and agricultural irrigation and drainage projects. With the emergence of drawbacks in traditional canal control models and the increasingly severe shortage of water resources, accurate transport and distribution of water in the canal system of the irrigation district, rational allocation of water resources, reduction in water loss, improvement in the efficiency and benefit of water resource utilization, and satisfaction of the water demand of different water users are needed. Many scholars have conducted extensive research on canal operation control and optimal scheduling. This paper systematically reviews and summarizes the relevant research progress, including the theory of unsteady flow in open canals, the operation mode of the canal system, the operation control model and algorithm of canal systems, and the optimization of water distribution in canal systems. By summarizing the research progress already achieved, the existing problems and future development directions are identified according to actual needs, providing a reference for the ongoing modernization of irrigation districts and the research and application of digital twin irrigation district technology.

RETROSPECTIVE ANALYSIS AND CLINICAL OBSERVATIONS OF REGENERATIVE FEATURES OF PERIAPICAL TISSUE

Abstract Background. Chronic forms of periodontitis are accompanied by changes in periapical tissues, untimely diagnosis and lack of full mechanical treatment increases the number of patients diagnosed with chronic periodonitis. Periodontitis, which leads to destructive changes due to a long-term inflammatory process in periapical tissues, is especially dangerous. For this reason, the problem of treating destructive forms of periodontitis is relevant in modern dentistry. The purpose of the study is to study the regeneration of periapical tissues after treatment of patients with chronic forms of periodontitis. Methods. A retrospective analysis of the destruction and restoration of periapical tissues before and after treatment in the period of 3-6 months was carried out in 20 patients. Results. According to the results of a retrospective analysis of X-ray studies, bone tissue destruction of varying degrees was revealed in 20 patients. Poor preparation of the root canals was due to a number of factors, the main one being the anatomy and topography of the root canals. Of the 20 patients requiring treatment for chronic periodontitis with varying degrees of destruction, 16 patients came to the next stage and underwent endodontic treatment. After the treatment, conical preparation of the root canals and the quality of obturation to the radiographic apex of the root were radiographically revealed. In patients with clinical signs of periodontitis, an X-ray examination was performed after 3 months, in patients without clinical manifestations - after 6 months. After 3 months, the X-ray showed a decrease in the foci of bone tissue destruction in the area of the causative tooth, and positive dynamics were determined. Conclusion The study of periapical tissue regeneration after treatment of patients with chronic forms of periodontitis showed that effective apical preparation, high-quality irrigation and root canal filling increases the degree of regeneration in the periodontium. Healing in the periapical tissues is crucial for the success of root canal treatment.

A Maintenance Cost and Work Performance Analysis on Irrigation Network at Kaubun Irrigation Area of East Kutai Regency, Indonesia

An irrigation network maintenance is an effort to maintain and secure the irrigation network to be always ready and well functioned. In facilitating its operational implementation and maintain its sustainability cycle, it can be attained through maintenance, repair, prevention, and security activities that must be conducted in continuity. The Kaubun irrigation area is one of the irrigation areas under the authority of central government with area length of 1,150 Ha (standard area) and 736 Ha (functional area), located in the East Kutai Regency. The Kaubun irrigation area has 1 (one) weir or dam and 2 (two) main canals. The irrigation network maintenance has not been carried out in routine and periodical ways either by the East Kalimantan Provincial Government or by the East Kutai Regency Government. Sediment accumulation is one of the main problems found in the secondary irrigation canal and able to cause canal blockage, reduced water flow capacity and increased infrastructure damage. This research was carried out by evaluating the Irrigation Network System and observing several factors causing channel damage with a guidance from regulation of Minister of Public Works and Public Housing Number:12/PRT/M/2015 on date 6 April 2015, regarding Exploitation and Maintenance of Irrigation Network. Result of the research showed that recapitulation of the work performance index for Kaubun Irrigation Network System was obtain the largest optimum value in Physical Infrastructure aspect with an index value of 29.01. Meanwhile, the result from main treatment priority by employing Analytic Hierarchy Process (AHP) method found the Physical Infrastructure aspect has a limiting value of 0.462. Finally, the routine and periodical maintenance costs for the Kaubun irrigation area is IDR.3.753.835.675.00