Assessment of the Impact of Sewage Storage Ponds on the Water Environment in Surrounding Area

Due to geographical limitations (lack of natural receivers of treated wastewater) large sewage storage ponds are the main method of sewage disposal in the Republic of Kazakhstan. The paper presents the results of research on the environmental impact of sewage ponds serving the city of Kostanay (Kazakhstan). The scope of the research included the determination of basic quality parameters of raw and treated wastewater, the analysis of the chemical composition of groundwater in the vicinity of sewage ponds, and the analysis of the water quality of the Tobol River. The obtained results showed that efficiency of treatment facilities was unsatisfactory and water quality in the ponds did not meet requirements for surface waters for fishery. Highest contamination of groundwater was observed in sampling points close to the sewage ponds and was decreasing while the distance from the ponds was increasing. Multivariate analysis of the research data indicated that sewage from storage ponds, infiltrating into the ground, may affect quality of groundwater, which in turn supplying the Tobol River may also determine the quality of the river water.

Assessment of the Impact of Sewage Storage Ponds on the Water Environment in Surrounding Area

The paper presents the results of research on the environmental impact of sewage ponds serving the city of Kostanay (Kazakhstan). The scope of the research included the determination of basic quality parameters of raw and treated wastewater, an analysis of the chemical composition of groundwater in the vicinity of sewage ponds, and the analysis of the water quality of the Tobol River. The obtained results indicate that sewage from storage ponds, infiltrating into the ground, caused groundwater pollution in the area of about 100 km2 around the reservoirs. Due to the fact that the groundwater aquifer in the vicinity of sewage ponds feeds the Tobol River, it also affects water quality in the river, which does not meet the requirements for most of the analyzed parameters.

Sewage sedimentation ponds – a lost bird paradise: a nostalgic return visit and case study

Sewage ponds with exposed sludge are known to be excellent feeding sites for waders during migration. They still exist in parts of the world but are disappearing in pace with introduction of modern methods which do not involve open exposure of the sludge. Here I report a five-year study from a Swedish plant with open sludge ponds in the 1950s when many similar ones were still active. I counted the waders with frequent visits from 18 April through 2 November, 1952–1956. Ninety-three percent of the dates had a visit in at least one of the years giving an almost complete combined coverage of migration. Nineteen species were recorded at least once. The total average annual number of bird-days was 2868 (5% in spring). Most abundant were the Ruff Calidris pugnax with 35% and Wood Sandpiper Tringa glareola with 32% of all bird days. Temminck’s Stint Calidris temminckii showed the highest spring proportion of bird-days, 30%.

An integrated sewage treatment pond-wetland challenges conventional process treatment performance

This paper presents a case example showing how integrating a constructed free water surface (FWS) wetland with sewage treatment ponds system can deliver effluent quality results that rival conventional sewage treatment plants (STP). Treatment ponds, commonly used in regional and remote communities, provide low cost and operationally simple wastewater treatment. Despite the benefits of sewage ponds, many systems struggle to achieve modern environmental standards. This paper focuses on the treatment performance of a pond-wetland STP throughout the initial 15-month establishment period of a 2,000 sqm FWS wetland at Helidon Queensland, Australia. The pre-existing STP comprised a two-stage pond with chlorination. In 2013, a two-cell FWS wetland was built to achieve long-term licence compliance at the STP for biological oxygen demand (BOD), total suspended solids (TSS) and pH. Post establishment, the effluent quality out of the wetlands was BOD <10 mg/L; SS < 20 mg/L; pH of 7–8 despite the influent BOD and TSS levels being well above the values used for the system's design. This paper demonstrates that FWS wetlands can easily integrate into existing or new sewage pond systems to deliver high quality and reliable treatment outcomes.

Primeros registros de Erythemis vesiculosa (Fabricius, 1775; Odonata: Libellulidae) y de Ischnura barberi Currie, 1903 (Odonata: Coenagrionidae) para Baja California Sur, México/Fisrt records of Erythemis vesiculosa (Fabricius, 1775; Odonata: Libellulidae) and Ischnura barberi Currie, 1903 (Odonata: Coenagrionidae) from Baja California Sur, Mexico

We report the first records of two species of Odonata for Baja California Sur. An individual of Erythemis vesiculosa was in the southern part of the state at San Pedro del Palmar, an oasis near Todos Santos, 1 October 2014, and a couple of Ischnura barberi were in the northern part of the state at the Guerrero Negro sewage ponds 21 October 2014; both were photographed. These observations increase to 57 the number of species of the order Odonata recorded in BajaCalifornia Sur.