Considering Water Quality of Urban Rivers from the Perspectives of Unpleasant Odor

Abstract

Surface water degradation in urban areas is a common problem in many countries, and degradation hampers ecosystem services provided by rivers, having negative impacts on aquatic organisms and human beings. Unpleasant odor arising from impaired rivers causes annoyance to people, and the study quantitatively analyzed unpleasantness of odor in Tokyo through the application of hedonic tones of odor. Unpleasantness remained or worsened while overall dissolved oxygen (DO) concentration increased downstream. The phenomenon is considered to be caused by multiple external factors, such as combined sewer outflow, hypoxia at Tokyo Bay, and effluent from water reclamation centers (WRC). Converting descriptive odor types into numeric values helped to see changes over time and enabled to depict the relation between DO concentration and the type of odor. In Tokyo, the ratio of effluent from WRC to stream flow increased over time, and it partially contributed to odor becoming more unpleasant. Malodor is no longer a major issue since the situation improved by developing an advanced treatment facility; however, human olfactory sense detects the existence of unpleasant odor in urban rivers. The study presented the complexity of analyzing odor problems in tidal urban areas because these are caused by external factors.

Penurunan BOD, TSS, minyak dan lemak pada limbah cair pabrik kelapa sawit menggunakan proses aerasi plat berlubang

“…Konsentrasi BOD menurun sampai di bawah ambang batas BML pada hari ke-2 sampai hari ke-4 dimana konsentrasi BOD yaitu 60,7 mg/L sampai 81,1 mg/L. Hal ini menunjukkan bahwa proses dekomposisi bahan organik terjadi dengan mengalirkan oksigen ke dalam LCPKS sehingga nilai BOD 5 juga menurun selama proses aerasi (Sado-Inamura & Fukushi, 2018).…”

“…Limbah cair pabrik kelapa sawit bila dibiarkan tanpa diolah lebih lanjut akan terbentuk amonia, hal ini disebabkan bahan organik yang terkandung dalam limbah cair tersebut terurai dan membentuk ammonia. Terbentuk amonia ini akan mempengaruhi kehidupan biota air dan dapat menimbulkan bau busuk (Sado-Inamura & Fukushi, 2018).…”

Performance Chitosan Membranes to Filter Humic Acid (HA) Waste from Aquatic Environment

“…Pollution that occurs can affect the physical of the river. River water will become cloudy and smelly [7]. If the humus content pollutes the river on a large scale, it will have an impact on living things in the river ecosystem.…”

Removal of hydrogen sulfide gas using coal fly ash – blast furnace cement composite

“…Currently, the number of complaints regarding offensive odors from service industries, such as restaurants and garages, has risen to 8,000 per year (Kamigawara 2003). Offensive odors are also generated by limestabilized biosolids, such as sewage sludge (Krach et al 2008), pet food, roofing tar, dead animals (Eltarkawe & Miller 2019), urban rivers (Sado-Inamura & Fukushi 2018), and Johkasou, such as a septic tank, a Japanese compact-scale advanced wastewater treatment system (Ichinari et al 2008;Fajri et al 2018).…”