Distribusi air di Kota Samarinda masih belum optimal dikarenakan factor tekanan air di dalam pipa yang rendah pada waktu tertentu dan kehilangan air fisik karena kebocoran. Artikel ini memuat analisis jaringan perpipaan distribusi air bersih di Kelurahan Harapan Baru, Kota Samarinda menggunakan perangkat lunak EPANET 2.0. Hasil simulasi dibandingkan dengan hasil pengukuran tekanan air di lapangan pada kran pelanggan menggunakan manometer. Dari hasil penelitian, diketahui terdapat sebanyak 7 junction yang nilai tekanan airnya di bawah batas minimum kriteria pipa distribusi dari Peraturan Menteri Pekerjaan Umum No.18/PRT/M/2007 sebesar 0,5 atm, serta sebanyak 11 pipa yang nilai kecepatan aliran airnya di bawah batas minimum kriteria yang sama sebesar 0,3 m/s. Rekomendasi perbaikan jaringan perpipaan distribusi air bersih berupa tekanan minimum sebesar 0,5 bar pada pelanggan dan kontinuitas, yakni perubahan pengaturan tekanan pada valve existing, dan penambahan pompa booster pada beberapa titik. Terdapat perbedaan nilai tekanan air yang cukup signifikan antara hasil simulasi model EPANET dengan pengukuran langsung pada kran pelanggan.

The application of bio-pore infiltration holes (BIH) can be one solution for urban runoff management by reducing surface runoff to the ground. But, the difference in soil types and characteristics could affect the runoff reduction that can be achieved by BIH. This research aims to determine the runoff reduction can be achieved by bio-pore infiltration hole (BIH) from different soil types and conditions. The methods in this study mainly focus on hydraulic conductivity calculations using Porchet method and the implementation of Minister of Environment Regulation Numb. 12/2009 for the BIH installations. Based on the implementation of Minister of Environment Regulation Numb. 12/2009, the required BIHs for the area of 500 m2 are 1,000, both for silt and clay soils. The runoff reductions that can be achieved with the application of BIHs are 38.98-95.73% for silt soils and 20.67-54.28% for clay soils, depends on the soil conditions.

Mahakam is the second longest river in Indonesia and it functions as a source of raw water for drinking and other essential activities for the Samarinda people. Furthermore activities in the watershed generate solid waste such as plastic, which enters the waters and is potentially degraded into microplastics. There is a possibility that the presence of microplastics is affected by anthropogenic types along the river. Therefore, this research aims to determine the effect of anthropogenic type and river depth on the microplastic abundance in the Mahakam River. The samples were taken using an integrated approach at 3 depths, namely 0.5, 1, and 1.5 m, in 2 locations with different anthropogenic types. The sampling points include Kampung Tenun and Bukuan Villages, which represented densely populated and non-populated areas, respectively. The water collected was prepared with the following steps, which include filtration with 180 μm nylon, elimination of organic matter, density separator, and final filtration. Microplastic samples were identified based on the type, color, size, and type of polymer using a microscope and FTIR. The results show that there are 3 types of microplastics, 4 colors, and 5 size categories dominated by fiber type, black, and the smallest size, respectively. There are differences in abundance in Kampung Tenun and Bukuan Villages, namely 91 particles/L and 71 particles/L, indicating the effect of the anthropogenic type. Sampling depth also affects abundance, hence, the greater the depth, the lower the abundance value. It was also discovered that anthropogenic type and depth factors influence the identified polymer types. Nylon and nitrile polymer types were found at 2 locations and 3 sampling depths, but PVC, PETE, and PS were only found at certain locations. Furthermore, Bukuan Village, with a greater environmental factor value, has a smaller abundance than Kampung Tenun Village. HIGHLIGHTS Anthropogenic types affect the microplastic abundance in Mahakam River water Sampling depth affects the microplastic abundance in Mahakam River water Microplastics are found in Mahakam River water in 3 forms, 4 colors, and 5 types of polymers, with a size range of 180 - 5000 µm Environmental factors affect the microplastic abundance in Mahakam River water GRAPHICAL ABSTRACT

Timbulan sampah akan meningkat seiring dengan pertambahan jumlah penduduk, sedangkan komposisi sampah mengalami perubahan setiap tahun akibat adanya perubahan pada pola hidup dan tingkat ekonomi masyarakat. Penelitian ini bertujuan untuk mengetahui keterkaitan tingkat pendapatan penduduk terhadap timbulan dan komposisi sampah, mengetahui keterkaitan tingkat pendidikan terhadap perilaku masyarakat dalam mengelola sampah, dan merekomendasikan sistem pengolahan sampah di Kecamatan Muara Badak berdasarkan klasifikasi jenis perumahan dengan pendapatan tinggi, menengah dan rendah. Pendekatan yang digunakan pada penelitian ini adalah kuantitatif dengan cara survei ke lokasi sampling dan didukung oleh kuesioner. Metode pengukuran timbulan dan komposisi sampah mengacu pada SNI 19-3964- 1994. Uji statistik yang digunakan untuk mencari keterkaitan antara variabel yang diamati dalam penelitian ini, yaitu melalui uji Anova one-way dan uji chi-square. Total berat dan volume timbulan sampah Kecamatan Muara Badak dari 3 kategori perumahan adalah sebesar 251,13 kg dan 3170 l dengan komposisi sampah terbesar di adalah sampah organik dengan persentase komposisi sampah sebesar 40,1%. Dari hasil analisis diketahui bahwa tingkat pendapatan tidak mempengaruhi jumlah timbulan sampah, namun dapat mempengaruhi komposisi sampah pada jenis tertentu. Selain itu, tingkat pendidikan juga tidak mempengaruhi perilaku kebiasaan masyarakat dalam mengolah sampah yang mereka hasilkan sehari-hari. Melihat dari jenis komposisi sampah yang paling mendominasi, sistem pengolahan sampah yang dapat direkomendasikan adalah pengomposan sampah berbasis TPS 3R.

Several attempts have been made to increase the permeable area in the cities, which include the building of green facilities such as parks and urban forests. Since these areas were built with soil compaction, the potential for infiltrating water differs compared with the natural green area. Therefore, this research aims to analyze the influence of soil conditioning on the constant infiltration rate using variables such as soil compaction, texture, and the presence of vegetation cover in urban facilities. The data used were obtained through field infiltration measurement using a single ring infiltrometer. In this research, the analysis carried out includes soil texture, Horton equation, the difference between conditioned soils and control plots, and USDA hydrologic soil classifications. The results showed that all variables (soil compaction, the presence of vegetation cover, and soil texture) have a significant effect on the constant infiltration rate. Based on the soil conditioning, the infiltration rate is increased on the vegetated plots and decreased on the plots with the combination of vegetation and compaction, as well as the compacted plots. Furthermore, the effect of vegetation cover is more significant in silt loam textured soil, while the influence of compaction is more on clay textured soil. The potential constant infiltration rate on the plots of similar characteristics with green urban areas are on K2 and L2 with 2.698 mm/h and 1.525 mm/h, respectively. Therefore, these plots have a moderate runoff potential based on USDA hydrologic soil classification. Keywords: Compaction; Infiltration; Soil conditioning; Urban facilities   Copyright (c) 2021 Geosfera Indonesia and Department of Geography Education, University of Jember This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License