Bengawan Solo River Basin Research Articles

Efficiency and Contribution of Labor in Rice Farming in the Lower Bengawan Solo River Basin, Bojonegoro Regency

Efficiency and Contribution of Labor in Rice Farming in the Lower Bengawan Solo River Basin, Bojonegoro Regency

Data Communication as a key to integrated river basin management

This article discusses data communication as a key to implement integrated water resource management (IWRM) in river basin management. The performance of a river basin is determined by many aspects/sectors which are managed by different level of governments and various agencies within them. Implementing IWRM requires integrated data information system provided by those various government agencies. Although it has been regulated in the Law No 17 Year 2019, integrated information system reliable to support decision-making process has not existed yet. This article reviews what is the condition of water related data in Bengawan Solo River Basin Management – the type of water related data, the data frequencies, and the data sharing mechanism. It aims to examine data communication among actors and supports the decision-making process in Bengawan Solo River Basin Management. There are three stages were undertaken to achieve this overall aim, that are 1) identifying the type of water-related data need be shared in sharing water resource from the literature; 2) identifying the availability of water-related data identified in the stage 1 in the existing data provided by government agencies; 3) conducting a series of focused group discussion (FGD) to elaborate the use of the available data to understand its limitations to support decisionmaking process. The research found that the implementation of IWRM in Bengawan Solo River Basin is difficult to be achieved because there is a lack of data communication among data providers. It points that the absence of data communication occurred because there is no definite data sharing framework specify what data need to be shared, the frequency of data collection and updating, and the mechanism in sharing data legitimated by all agencies involved in Bengawan Solo River Basin Management. Thus, it reveals that data cannot be used maximally to support effective river basin management not because of technology drawbacks or a lack of data, but its uncertainty on how data needs to be communicated. In addition, there no certainty of who is the responsible agency or authority to fulfill five aspects of data communication. This is the final homework of IWRM implementation in managing river basin in Indonesia.

Operation And Maintenance Of Cengklik Reservoir In Supporting Integrated Water Resources Management

The management of the Cengklik Reservoir area which currently still has the main function as an irrigation facility with an area of 1,578 ha is still in the feasible category to be developed as a means of tourism and sustainable aquaculture. The development of the Cengklik Reservoir area in 2022 has entered the stage of developing supporting infrastructure such as a jogging track area, reservoir guardrails, arrangement of fish cage cultivation areas, and other infrastructure developments. This must also be balanced with a good pattern of management of operation and maintenance (OP) activities in the form of documents prepared by referring to the Reservoir Operation and Maintenance (OP) Guidelines. The method used in this research is simulation and evaluation on hydrological analysis using a flood design of 476.40 m3/s and an average flood water level of +142.64 m. The data used to measure the management of water resources in the Cengklik Reservoir is based on data hydrology, inflow, and outflow of the Cengklik Reservoir from 2010-2021 based on observations from the Bengawan Solo River Basin Center (BBWS). According to the evaluation results with measured parameters, it was found that the pattern of operation and maintenance of the Cengklik Reservoir is in the feasible category with the need for funding for the operation and maintenance of the reservoir of IDR 474,397,817.00 So that the integrated water resources development that has been carried out in the Cengklik Reservoir can be replicated in the reservoir others throughout Indonesia.

Analysis Of The Issues On Bengawan Solo River Basin Management Policies

The Bengawan Solo river basin in Central Java Province, Indonesia, has a great history from era to era. But there are still issues with its current management system. Because of that, this paper aims to analyze issues in the management policies of the Bengawan Solo river basin. This is empirical legal research with qualitative analysis. The data were collected through interviews with informants who manage the Bengawan Solo river basin, from the Bengawan Solo River Management Office (RMO), the Environmental Service of Sukoharjo, Surakarta, and Karanganyar Regencies, as well as people who live around the Bengawan Solo river. Research showed that issues that concern the Bengawan Solo river basin are: (1) river basin pollution due to textile waste that is illegally disposed of in the river, and (2) there is a lack of regional regulations that are specially made to manage river basins. Based on the issues faced by the Bengawan Solo river basin, there needs to be a change in the policies on river basin management. There should be a special regulation on the Bengawan Solo river basin area. Apart from that, the Bengawan Solo river basin management should be changed into more effective management patterns.

Development of A Two-storage Reservoir Operation Rules for Flood Control Case Study of Wonogiri Multipurpose Reservoir, Central Java, Indonesia

Wonogiri Reservoir, one of the large reservoirs in Indonesia, regulates water for flood control, irrigation, domestic use, and hydropower. It is located at the upper part of Bengawan Solo River Basin, Central Java. A closure dike has recently been constructed as a countermeasure against severe sedimentation that separates the reservoir into two parts, i.e., Sediment Storage Reservoir (SSR) and Main Reservoir (MR). A two-gate spillway was constructed in the SSR to facilitate sediment flushing and sluicing. During flood events, it controls reservoir water level jointly with the MR spillway. This brings the need for an update on the reservoir operation rules, especially on the gates opening of the new spillways to maintain the flood control performance. An assessment of reservoir routing simulation results was carried out by considering the overflow from SSR to MR, or vice versa with two options of Control Water Level (CWL), i.e. +135.8 m and +136.3 m. The flood control performance of the new reservoir operation rules was evaluated by considering the reservoir water level recovery, the maximum total outflow discharge, and the dam safety due to the risk of overtopping. These assessments give a foundation for the selection of CWL and the spillway operation to ascertain an optimal flood control of the reservoir.

The Use of Data and Information in Irrigation Water Management (Case Study: Colo Irrigation Area, Bengawan Solo River Basin)

In term of geography, water is a resource which is not favouring administrative boundaries. Water has its behaviour in flowing. However, we cannot confidently say that water flows following the laws of gravity. There is no guarantee that locations which are close to reservoir or water resource are not prone. Water scarcity when comparing the resource to demand for it is more relative than absolute. Irrigation water management is aimed to guarantee to make every agricultural land has access to water. In other hand, map is an important tool especially for portraying conditions of an area such as river basin. Map have played important roles in water management. This study aims to explore the use of data in decision making in irrigation water management practices. Colo irrigation area in Bengawan Solo river basin was chosen not only its vast coverage area but also because of its complexity in water management. It across two provinces and six municipalities. Content analysis was undertook to analyse two data sets: laws and regulation related to water management practice and the interview of policy actors. Elaborating the implementation of laws and regulations regarding to the use of data and information in irrigation water management, the comparison of the results also disclosed deviations among what it is regulated and what it is implemented. Quantitative and qualitative data that mostly used in practices cannot fully support to inform water conditions, physical and environmental conditions, social economic conditions in wider context. Spatial data is essential tools to represent comprehensive interconnected data and information in wider context. A profound understanding of stakeholder perspectives on the role of each data and information is essential for policy actors in the implementation of integration water resource management. Shared, comprehensive and interconnected data can promote common ground and collaboration potential.

Preliminary study of magnetic susceptibility on fine sediment Bengawan Solo river

Magnetic susceptibility of fine sediment Bengawan Solo river basin was presented. The appearance of magnetic susceptibility of fine sediment indicates the existence of a magnetic field source. Kappa meter type KT-6 is used for roughly mapping the magnetic source in fine sediment for a large enough area. Then, the actual fine sediment content is evaluated by using the x-ray fluorescence (XRF) and x-ray diffractometer (XRD). More than a hundred sampling points have measured susceptibility along with the mouth Bengawan Solo river at Bojonegoro Regency. The XRF and XRD result confirms that the largest content of the fine sediment as magnetite. Finally, the magnetic properties of the fine sediment are confirmed that the magnetic source is magnetite.

Analysis of Intensity, Duration, Frequency for Groundsill Planning in the Lower Bengawan Solo River Basin

Hydrological analysis is the most important thing in the planning of a water building, including rain. Rainfall characteristics include the intensity of rain (I), length of time of rain (t), depth of rain (d) and Frequency (f). Rainfall intensity can be used to calculate the flood discharge plan using the Rational method. In this study daily rainfall is calculated by analyzing the frequency that starts by determining the average maximum rainfall, then calculating the statistical parameters whose function is to choose the appropriate distribution. So that an appropriate distribution is obtained, namely the Pearson Type III log distribution. From the results of this distribution can calculate the rainfall plan with various times, namely 2,5,10,25 and 50 years. Then the rainfall intensity is calculated using the Mononobe method. The final result of this research is the Intensity Duration Frequency curve. (IDF).

Application of TRMM in the Hydrological Analysis of Upper Bengawan Solo River Basin

Rainfall is a major water resource with a significant role in terms of growth, environment concerns, and sustainability. Several human activities demand adequate water supply for drinking, agriculture, domestic, and commercial consumption. The accuracy of any hydrologic study depends heavily on the availability of good-quality precipitation estimates. Most countries are unable to provide sufficient climatic data, including rainfall and observed discharge statistics. This scarcity is a huge obstacle in conducting thorough hydrologic studies over a certain period. For instance, Indonesia, as an archipelagic country, has long been faced with data availability problems. For this reason, Tropical Rainfall Measuring Mission (TRMM), which was developed by NASA, became an alternative solution to rainfall data limitations. However, to be applied in hydrologic investigations, TRMM data require proper estimation and adjustment. The aim of this study was to evaluate the quality of TRMM rainfall data and its application in determining design flood and water availability. Dividing the data into several groups based on its magnitude and multiplying each unit with a correction coefficient are parts of the modification process. Subsequently, objective functions, including false alarm ratio (FAR), probability of detection (POD), and root mean square error (RMSE) were also applied. Rainfall-runoff modeling and design storm analysis at Delingan dam were used to study the TRMM correction performance. Based on the analysis, corrected TRMM showed considerable findings compared to ground station data. Model calibration and verification using corrected TRMM data provide satisfactory model parameters compared to ground station derivatives. The results also disclosed a closer fit of the corrected TRMM to catchment response translated from derived rainfall-runoff model parameters to ground station compared to control. Furthermore, design storm calculated from corrected TRMM reflects an improvement compared to uncorrected TRMM data.

Penurunan Parameter Pencemar Limbah Cair Industri Tekstil Secara Koagulasi Flokulasi (Studi Kasus: IPAL Kampung Batik Laweyan, Surakarta, Jawa Tengah, Indonesia)

The batik home industry of Kampung Laweyan, Surakarta City did not make efforts to prevent environmental pollution from the wastewater produced. Waste water is discharged into the Jenes river, so that the river becomes polluted and contributes to the pollution of the Bengawan Solo River Basin. The study was conducted at the Environmental Laboratory, Environmental Engineering Study Program, Faculty of Engineering, Surakarta Christian University by conducting the coagulation process of flocculation with the jart test. This study uses variations and dosages of the type of FeSO4 and PAC coagulants with levels of 5% each for 100 ml / sec waste discharge. The results of the research are that before the waste is processed by the coagulation process, the value of BOD = 660.28 mg / l and COD = 1600. After the coagulation process, the efficiency of each type of coagulant is with FeSO4, BOD = 85.63% and COD = 82.67 %. With PAC coagulant, BOD = 90.21%, COD = 88.97%. This shows that the ability of PAC to reduce pollutant parameters is greater than ferrous sulfate.

Optimasi Pengelolaan Waduk Pondok Ngawi Jawa Timur

Pondok Reservoir is one of the smaller reservoirs built in Bengawan Solo River Basin, located in Kali Dero, Gandong Village, Bringin District, Ngawi District, with a puddle of 3.6 km2 and 32.9 km2 of drainage area. The total reservoir volume is 25,233 MCM and the effective dams volume is 22,333 MCM. The reservoirs are used to irrigate 3.596 Ha of irrigated rice fields which are distributed through four weirs, namely Dero weir, Sambiroto dam, Plesungan dam, and Padas dam. The results showed that selected crops were rice and maize, while to obtain maximum annual agricultural benefit benefit can be done with the initial period of planting for the first planting season is the third week of November, which has annual net benefit value of agriculture of Rp. 10,797,000,000. Through continuous water supply, the optimal planting area for each planting season is the first planting season in the third week of November with rice plant of 2877 ha and 719 ha of maize; the second growing season in the third week of March with rice plants 1216 ha and 1216 ha of maize; third planting season in the third week of July with 402 ha of corn. Percentage of planted area from available land per planting season is: first planting season is 100%, second planting season is 67,63% and planting season is 11,18%, so planting intensity is 178,8%.

Simulation and prediction the impact of climate change into water resources in Bengawan Solo watershed based on CCAM (Conformal Cubic Atmospheric Model) data

Bengawan Solo Watershed is one of the largest watersheds in Indonesia. This watershed flows in many areas both in Central Java and East Java. Therefore, the water resources condition greatly affects many people. This research will be conducted on prediction of climate change effect on water resources condition in terms of rainfall conditions in Bengawan Solo River Basin. The goal of this research is to know and predict the climate change impact on water resources based on CCAM (Conformal Cubic Atmosphere Model) with downscaling baseline (historical) model data from 1949 to 2005 and RCP 4.5 from 2006 to 2069. The modeling data was validated with in-situ data (measurement data). To analyse the water availability condition in Bengawan Solo Watershed, the simulation of river flow and water balance condition were done in Bengawan Solo River. Simulation of river flow and water balance conditions were done with ArcSWAT model using climate data from CCAM, DEM SRTM 90 meter, soil type, and land use data. The results of this simulation indicate there is (i) The CCAM data itself after validation has a pretty good result when compared to the insitu data. Based on CCAM simulation results, it is predicted that in 2040-2069 rainfall in Bengawan Solo River Basin will decrease, to a maximum of only about 1 mm when compared to 1971-2000. (ii) The CCAM rainfall prediction itself shows that rainfall in Bengawan Solo River basin will decline until 2069 although the decline itself is not significant and tends to be negligible (rainfall is considered unchanged) (iii) Both in the DJF and JJA seasons, precipitation is predicted to decline as well despite the significant decline. (iv) The river flow simulation show that the water resources in Bengawan Solo River did not change significantly. This event occurred because the rainfall also did not change greatly and close to 0 mm/month.

KETERSEDIAAN DAN KEBUTUHAN AIR DI PROVINSI JAWA TENGAH DAN JAWA TIMUR

There are two objectives of this research. First, to calculate water available and water need in the research area and second, to analysis the water balance. Water available cover rivers water and springs water, whereas water need cover domestic usage, industrial usage, rivers protect, cattle, fi shery and irrigation. As a result, show that the biggest water available in Central Java is in Serayu River Basin namely 8615.33 million m3/year, whereas the smallest is in Juana River Basin namely 88.39 million m3/year. In East Java, the biggest water available is in Downstream Bengawan Solo River Basin namely 26149.38 million m3/year, whereas the smallest is in Luminu Penguluran River Basin namely 45.26 million m3/year. Base on the water balance, the water balance of both province are also variatifl y. In Central Java, Serang-Lusi, Juana and Citanduy River Basin get water defi cit along years, whereas in East Java, it is just Luminu Penguluran River Basin that get defi cit along years. According the water surplus, Serayu River Basin in Central Java and Downstream Bengawan Solo River Basin in East Java get water surplus along years.Key words : water available, water need, water balance

Irrigation System Performance Evaluation of Sub Irrigation Area of Jejeruk Kiri Tambran Using Public Works Minister’s Regulation No. 32 in 2007 and Fuzzy Set Theory

Sub irrigation area of Jejeruk Kiri Tambran, physically, has performance degradation due to aging buildings and nature factors. Therefore, performance evaluation of irrigation system is needed as a part of the asset management of irrigation to determine the functioning of the irrigate ion asset. The procedures of performance evaluation refers to Public Works Minister’s Regulation No. 32 in 2007, concerning to Operation and Maintenance of Irrigation System, which is consist of 6 main aspects, there are physical infrastructure, productivity of planting, supporting facilities of operation and maintenance, personnel organization, documentation, and water user farmer association. This kind of evaluation contains fuzziness and uncertainty in valuing based on observation dan human opinion. Hence, a method that can accommodate the problem is needed, one of which is fuzzy set theory method. The aim of this research is comparing performance evaluation of irrigation system by using manual method of Bengawan Solo River Basin Agency which is refers to Public Works Minister’s Regulation No. 32 in 2007 and fuzzy set theory. The result performance value of irrigation system of sub Jejeruk Kiri Tambran is 77,69% based on manual method and 73,45% based on fuzzy method. By t-test, there is no significant diference between both methods.

SOIL QUALITY INDEX IN THE UPSTREAM OF BENGAWAN SOLO RIVER BASIN ACCORDING TO THE SOIL FUNCTION IN NUTRIENT CYCLING BASED ON SOYBEAN PRODUCTION IN AGROFORESTRY

Over the function of the upstream region watersheds causes the soil susceptible to degradation of soil fertility. Agroforestry systems that have been implemented should be reviewed to determine their effectiveness in improving soil fertility using a soil quality index. The varieties of soybean that cultivated in the study site were Grobogan, Kaba, and Argomulyo. The variables of this study consists of organic-C, pH, cation exchange capacity (CEC), total-N, available-P, available-K, Na, Ca, Mg, base saturation, and electrical conductivity (EC). Soil quality index calculation performed on selected outcome variables principal component analysis (PCA) which is then multiplied by the weights index on each PC. Selected variables from PCA consist of available-P, available-K, base saturation, and pH. Soil quality index values for all types of Agroforestry in the upstream of Bengawan Solo river basin ( Wonogiri ) is under secondary forest (<4.1) so that it can be concluded that the adoption of Agroforestry in the upstream of Bengawan Solo river basin has not effect on soil quality based on soil functions in the recycling of nutrients. Mean of soybean grain yield in agroforestry system are higher than the mean of national soybean production, but there are an obstacle such as light conditions.

Determination of Soil Quality Index Based on Soil Chemical Properties in The Upstream of Bengawan Solo River Basin Wonogiri

Title : Determination of Soil Quality Index Based on Soil Chemical Properties at The Upstream of Bengawan Solo River Basin Wonogiri. Land conversion extended to the upper of the watershed for residential and agricultural so soil’s ability is decreased to support the soil quality. To solve these problems, in the region upstream of Bengawan Solo, enforced by Agroforestry plantings. Research carried out at the upstream of Bengawan Solo Wonogiri and Laboratory of Chemistry and Fertility of Soil Faculty of Agriculture, Sebelas Maret University Surakarta, in June 2013 until March 2014. Research used a survey method by descriptive and exploratory. Determination of the location of the site sample is done by a stratified random sampling based onland map unit. Sampling was done by a purposive sampling method. The soil quality index is determined by summing the scores for each variable which has selected from Principal Component Analysis (PCA), and then it multiplied by the weight index. The result of the study show that the soil quality of Agroforestry in the upstream of Bengawan Solo Wonogiri based on the chemical properties of the soil is low. The value of soil quality index in the secondary forest is 2.6. While in the Agrosilvopastoral is 2.3 and in the Agrisilviculture is 2.1, which are lower than the secondary forest. Whereas in the Silvopastoral is 3.0, which is higher than the secondary forest.

Assessment of insurance for paddy production: a case study in Indonesia

The present study demonstrated the importance of designing insurance as a part of broader risk management, using pilot insurance for rice farmers in East Java, Indonesia, as a case. An independent-sample t-test, using historical data on the areas of monthly rice harvest failure at regency level for the recent 10 years, finds that harvest failure during the rainy seasons in a group of the regencies located in the Bengawan Solo River Basin is significantly greater than the other group consisting of the remaining regencies in the province. This is due to frequent floods, which are largely attributed to the declining function of the Wonogiri reservoir as the primary flood control facility. It suggests the necessity of risk prevention measures, such as those to pump out dead storage and upgrade spillway capacity, to allow insurance to work in the basin. The present study also investigated a feasibility of weather index insurance. It compares the correlation coefficients and statistical significance of monthly rice harvest failure between 29 regencies in the province on one hand, and those of monthly rainfall on the other. It finds that rice harvest failure has higher spatial dependency than rainfall, indicating a potential problem of a basis risk.