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Many studies have identified the potential of rainwater harvesting (RWH) systems to simultaneously augment potable water supply and reduce delivery of uncontrolled stormwater flows to downstream drainage networks. Potentially, such systems could also play a role in the controlled delivery of water to urban streams in ways which mimic baseflows. The performance of RWH systems to achieve these three objectives could be enhanced using Real-Time Control (RTC) technology to receive rainfall forecasts and initiate pre-storm release in real time, although few studies have explored such potential. We used continuous simulation to model the ability of a range of allotment-scale RWH systems to simultaneously deliver: (i) water supply; (ii) stormwater retention; and (iii) baseflow restoration. We compared the performance of RWH systems with RTC technology to conventional RWH systems and also systems designed with a passive baseflow release, rather than the active (RTC) configuration. We found that RWH systems employing RTC technology were generally superior in simultaneously achieving water supply, stormwater retention and baseflow restoration benefits compared with the other types of system tested. The active operation provided by RTC allows the system to perform optimally across a wider range of climatic conditions, but needs to be carefully designed. We conclude that the active release mechanism employing RTC technology exhibits great promise; its ability to provide centralised control and failure detection also opens the possibility of delivering a more reliable rainwater harvesting system, which can be readily adapted to varying climate over both the short and long term. [ABSTRACT FROM AUTHOR]

We examined the bacterial communities in a pool of water under a flowing rock fracture at a depth of 1470 m in the Sanford Underground Research Facility in Lead, SD. High-throughput sequencing of 16S rDNA indicated that Acidobacteria, Chlorobi, Nitrospirae, Planctomycetes, and Gammaproteobacteria (especially Acidiferribacter) were abundant in pool sediments; while Nitrospirae, Plactomycetes, and Proteobacteria (especially Thiobacillus and Methylococcus) were abundant in pool water. Samples of diluted pool water were mixed with agar media, placed in diffusion chambers surrounded by 0.2 µm pore membranes, and incubated in situ within the pool for 19 days. 16S rDNA analysis of media from diffusion chambers indicated Alphaproteobacteria (including Hyphomicrobium), Betaproteobacteria (including Inhella and Methyloversatilis), and Gammaproteobacteria (mainly Pseudomonas) were dominant. Low-nutrient media were used to isolate bacteria from both pool water and media inside diffusion chambers. The majority of these isolates were Methyloversatilis, Inhella, and Bacillus. Although the genera isolated were not very abundant in the pool water, the presence of Methylococcus and Methyloversatilis suggests the importance of methane and methanol oxidation in this community. [ABSTRACT FROM AUTHOR]