Hasil Aman Penurapan Airtanah untuk Kebutuhan Non Pertanian di Kabupaten Bantul

There are three objectives of this research. First, to calculate the potency of groundwater in Bantul District, second, to calculate the utilization for non agricultural usage and third, to analyze the safe yield of groundwater exploitation for non agricultural usage. To achieve these objectives, groundwater potency is calculated by static method, i.e. by multiplying area width, aquifer thickness and specific yield. Non Agricultural usage is determined by calculating the water utilization for domestic, industry, hotel and livestock. Safe yield is calculated base on area width, groundwater fluctuation and its specific yield. The groundwater resources potency of research area that has area width 506,85 km², amounted 10.059.393.198 m³/year, whereas the safe yield is 260.365.868 m³/year. Water utilization for domestic, industry, hotel and livestock is 21.658.541 m³/year. Reviewed number of potency and utilization, the potency of groundwater in the research area is still able to meet its water needs for non agricultural because the usage have not exceeded its safe yield. Although the groundwater potency is high, the agricultural sector in Bantul District does not use groundwater resources significantly

THE POTENTIAL OF RAINFALL AND ITS IMPACT TO GROUNDWATER STORAGE IN JAVA ISLAND

The objectives of the study are to map the distribution of rainfall in Java, to analyze its potential and the impact to groundwater storage. To achieve those goals, rainfall distribution is mapped using isohyet method. From the average distribution of monthly rainfall, the annual potential of rainwater on every watershed was calculated. Afterwards, the groundwater storage was analyzed and counted by applying the water balance concept. The results of the study show that the mean of the highest annual rainfall is 4082 mm which occurs on Cisadane- Ciliwung watershed and the lowest one is 1421 mm on Citarum Hilir watershed. From the rainfall potential, Cisadeg-Cikuningan watershed has the highest rainfall potential at the amount of 25342 million m31month and Grindulu Panggul watershed has the lowest potential at the amount of 3678 million m3lmonth. Meteorologically, Cisadeg-Cikuningan watershed has the highest groundwater storage at the amount of 6088 million m31yearand the lowest amount of it occurs on Madura watershed at 78 million m3lyear

Neraca Air di Pulau Bali

As a main destination of tourism in Indonesia, Bali develops rapidly. The impact of this phenomena is the increasing of water need in some sectors, whereas the available of water is constant. 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 groundwater, rivers water and springs water, whereas water need cover domestic usage, industrial and hotel usage, cattle, fishery and irrigation. Groundwater is estimated by water balance concept, river water and spring data is collected from BPSDA Bali Province, whereas the water need is counted base on secondary data that collected from some departments in Bali Province. As a result, show that the water available in Bali Island is 2.604.483.300 m³/year, which consist of groundwater 693.296.200 m³/year, rivers water 1.903.678.000 m³/year and springs 7.509.600 m³/year. The water needs reach 1.213.625.300 m³/year, which consist of domestic usage 121.276.260 m³/year, industrial and hotel usage 20.038.068 m³/year, cattle 31.272.435 m³/year, fishery 125.305.574 m³/year and irrigation 915.733.000 m³/year. Base on the water balance ratio, it is known that the number of ratio is 47% that it means almost in critical point

Groundwater Vulnerability from Sea Water Intrusion in Coastal Area Cilacap, Indonesia

The important issue relating to water resources is sea water intrusion (SWI) phenomena. Nowadays, the phenomena has become serious problem in the urban coastal area. Groundwater as main sources for domestic usage cannot be used again because of its salinity.Cilacap as one of urban coastal area also face the problem. In 1977 SWIwas detectedand experienced significant developmentsin 1996,This research was conducted to: (1) analyze agroundwater vulnerability to the SWI; (2) determine adistance and adepth theinterface; and (3) analyze relationship of the groundwater vulnerability to the interface depth.It was performed an analysis of the groundwater vulnerability to the SWI using the method of GALDIT, whereas the distance and depth of the interface was determined using the method of DupuitGhyben-Herzberg. The linkage analysis of the groundwater vulnerability to the depth of the actual interface was conducted by quantitative descriptively.The results showed that the distance from the shoreline was the most determined factor of the groundwater vulnerability to the SWI, the closer to the shoreline the more swallow the depth of the interface.  It existed the relevance between the vulnerability level of groundwater to the SWI with the depth of actual interface. The regions with low level of vulnerability had deep interface depth, whereas the regions with moderate level of vulnerability had swallow interface depth.  Nevertheless, the SWI has not yet affected the groundwater in people wells because of its depth that was not yet exceeded of 25 m.so that this depth can be used as a reference in digging wells in the research area+

Infiltrasi Tanah Di Kecamatan Nguter

INTISARI: Tujuan penelitian ini adalah uniuk mengetahui laju infiltrasi tanah di daerah penelitian serta menganalisis pengaruh faktor penggunaan lahan dan jenis tanah terhadap besar kecilnya laju infiltrasi di daerah penelitian. Untuk mencapai tujuan tersebut dilakukan pengukuran infiltrasi dengan menggunakan ring infiltrometer ganda. Penentuan titik pengukuran dilakukan secara purposive sampling dengan memperhatikan faktor penggunaan lahan dan jenis tanah, sedangkan analisis data dilakukan dengan menggunakan persamaan Horton. Hasil penelitian menunjukkan bahwa laju infiltrasi tanah di daerah penelitian berkisar antara 0,002 cm/menit dan 0,079 cm/menit, dengan rata-rata 0,0132 cm/menit. Nilai ini tergolong rendah, sehingga diperkirakan di daerah penelitian terjadi limpasan permukaan yang cukup tinggi. Ditinjau dari faktor penggunaan lahan, tegalan mempunyai laju infiltrasi tertinggi, disusul oleh permukiman dan terendah adalah sawah. Ditinjau dari faktorjenis tanah, jenis Mediteran mempunyai laju infiltrasi yang jauh lebih tinggi dibandingkan pada jenis Grumusol. Oleh karena itu, disimpulkan bahwa perbedaan jenis tanah relatif lebih berpengaruh terhadap laju infiltrasi air Ice dalam tanah dibandingkan dengan perbedaan penggunaan lahan. Berdasarkan agihannya, daerah yang terletak di dekat Bengawan Solo umumnya mempunyai nilai laju infiltrasi yang lebih besar dibandingkan dengan daerah yang berada lebih jauh dari sungai. Untuk kapasitas infiltrasi hal ini berlaku sebaliknya. Kala Kunci : Laju Infiltrasi, Kapasilas Infiltras

Identifikasi Keterdapatan Airtanah Dengan Electromagnetic Very Low Frequency (EM-VLF) di Non Cekungan Airtanah Kecamatan Ungaran Timur

Airtanah merupakan seluruh air yang berada di bawah permukaan tanah yang berada pada zona jenuh air. Keterdapatan airtanah dapat ketahui keberadaannya dengan metode geofisika. Metode geofiska berdasarkan elektromagnetik memiliki keunggulan untuk merambatkan gelombang pantul relatif lebih dalam dibanding metode geofiska yang lain. Hal tersebut dikarenakan oleh sifat geolmbang dengan rentang 0,2-30 kHz atau sepanjang hingga 20 km, jika dipancarkan (induksi) ke dalam tanah, sehingga mendapatkan sensitivitas terhadap setiap material lapisan batuan lebih dalam dengan satuan pengukuran nilai konduktivitas. Berdasarkan keunggulan tersebut induksi yang dalam, maka tujuan dari penelitian ini adalah untuk mengetahui keterdapatan airtanah di daerah non Cekungan Airtanah (Non CAT) dengan keberadaan airtanah yang relatif dalam, dengan metode Electromagnetic Very Low Frequency (EM-VLF). Berdasarkan hasil penelitian menunjukkan bahwa 6 dari 35 titik pengukuran tidak ditemukan airtanah. Kedalaman airtanah rata-rata berada pada kedalaman 10 m dengan potensi debit rata-rata 1 m3/jam (0,27 liter/detik) pada Non CAT bagian utara, dengan penyusun litologi akuifer batupasir perselingan lempung. Kedalaman rata-rata pada Non CAT bagian selatan adalah 25 m dengan potensi debit rata-rata 3 m3/jam (0,83 liter/detik). Litologi akuifer bagian selatan tersusun atas batuanbeku perselingan pasiran. Secara keseluruhan nilai tersebut masuk kedalam kelas debit kecil (< 0,55 l/detik) dengan akuifer bersifat lokal

Groundwater Vulnerability to Pollution in Kasihan District, Bantul Regency, Indonesia

The groundwater vulnerability to pollution refers to the ease of pollutants reaching groundwater, so the groundwater will be polluted. The concept shows a probability that pollution will occured which basically bases on the assumption that the physical environment can prevent the flow of pollutants into the aquifer. The purpose of this study was to predict the vulnerability of groundwater in the study area against pollution. To achieve these objectives beside base on secondary data, also measured the depth of phreatic surface, slope and groundwater sampling. Location of measurement and sampling is determinated by considering location of infiltration measurement ever done by Purnama in 2017. To conduct groundwater vulnerability analysis on pollution in the study area, carried out by SINTACS Method which bases on a numerical system of weight and rating. Weight are determined based on the significance of the effect of the parameters on groundwater pollution, while the rating is determined based on the significance of the influence of variables in each parameters against groundwater pollution. As a result, it is known that groundwater vulnerability indeks in research area range from 117,0 to 189,9. According to criteria of SINTACS, the value are classified as moderate vulnerability and rather high vulnerability. Areas that include moderate levels of vulnerability generally located in Sentolo Formations that consist of limestone and has grumusol soil type. Areas that classified as rather high vulnerability is located in Yogyakarta Formation that consist of volcanic rock and has regosol soil type. Based on this phenomena, it can be said that geological aspect and type of soil greatly affect the vulnerability of groundwater to pollution in the research area

Pemanfaatan Teknik Geolistrik Untuk Mendeteksi Persebaran Airtanah Asin Pada Akuifer Bebas Di Kota Surabaya

INTISARI Tujuan penelitian ini adalah untuk mengetahui persebaran airtanah asin di Kota Surabaya, menganalisis faktor penyebabnya dan mencari kemungkinan ditemukannya airtanah tawar pada akuifer tertekan. Untuk rnencapai tujuan tersebut dilakukan pendugaan geolistrik pada tujuh penampang dengan masingmasing penampang terdiri atas dua hingga tiga titik pendugaan. Untuk menganalisis hash pendugaan, data tahanan jenis hash pendugaan lapangan diinterpretasi dengan Program Schlumberger 0 Weil. Hasil interpretasi dapat ditentukan kedalaman dan ketebalan lapisan airtanah beserta sifat-sifatnya. Hasil penelitian menunjukkan bahwa di Kota Surabaya telah terdeteksi adanya airtanah asin dan airtanah payau, dengan jarak dari garis pantai dan ketebalan lapisan yang beniariasi. Faktor penyebab adanya airtanah asin dan airtanah payau tersebut adalah air fosil (connate water) Hasil lain dari penelitian ini adalah bahwa hingga kedalaman 150 meter dari pennulcaan tanah, tidak ditemukan alatifer tertekan yang mengandung airtanah tawar. Kata kunci: teknik geolistrik, airtanah asi

Ketersediaan dan Kualitas Airtanah pada Akuifer Tidak Tertekan Di Kecamatan Jawilan dan Kopo, Kabupaten Serang

Tujuan dari penelitian ini adalah (1) mengetahui sistem akuifer di daerah penelitian, (2) menghitung ketersediaan airtanah pada akuifer tidak tertekan dan (3) menganalisis kualitas airtanahnya. Sistem akuifer diketahui dengan melakukan interpretasi data geolistrik. Potensi akuifer tidak tertekan dihitung secara kualitatif melalui skoring dan tumpang susun antara Peta Kedalaman Muka Airtanah, Peta Fluktuasi Airtanah dan Peta Kualitas Airtanah. Volume akuifer ditentukan berdasarkan perkalian antara luas wilayah masing-masing potensi dan tebal akuifer. Ketersediaan airtanah dihitung berdasarkan asumsi aliran airtanah statik, sedangkan hasil aman pengambilan airtanah ditentukan berdasarkan parameter fluktuasi airtanah, luas akuifer dan spesifik yield. Kualitas air dianalisis berdasarkan pengambilan sampel air pada sumur gali. Hasil penelitian menunjukkan bahwa di daerah penelitian ditemukan adanya akuifer semi tertekan dan akuifer tidak tertekan. Ditinjau dari potensinya, ketersediaan airtanah pada akuifer tidak tertekan sebesar 1.205.967.345 m3, dengan hasil aman pengambilan airtanah sebesar  54.585.307 m3/tahun. Untuk kualitas air, secara umum baik, meskipun beberapa parameter seperti kalsium, magnesium, mangan dan COD kadarnya telah melampaui baku mutu  di beberapa sampel.ABSTRACT The objectives of the research are (1) knowing the aquifer system in research area, (2) calculate groundwater availability in unconfined aquifer and (3) analysis the groundwater quality. Aquifer system is known by interpretation of geoelectric data. Groundwater potency is calculated qualitatively by scoring and overlay of Groundwater Depth Map, Groundwater Fluctuation Map and Groundwater Quality Map. Aquifer volume is calculated by multiplied area width of each potency and aquifer thickness. Amount of groundwater is calculated base on static groundwater flow assumption, whereas safe yield of groundwater exploitation is determined base on parametre groundwater fluctuation, aquifer width and specific yield. Groundwater quality are analized by groundwater samples that taken from dug well. Result of research show that there are two aquifer type in research area i.e. semi confined aquifer and unconfined aquifer. The potency of unconfined aquifer is 1.205.967.345 m3, with safe yield 54.585.307 m3/year. For groundwater quality, generally good, although some parameters have concentration exceeded the standard in some samples such as calcium, magnesium, manganese and COD