archive-org.com » ORG » D » DECENTRALIZEDWATER.ORG

Total: 93

Choose link from "Titles, links and description words view":

Or switch to "Titles and links view".
  • decentralizedwater.org
    DESCRIPTION The use of real time sensors and supervisory control and data acquisition SCADA systems has not been widely used in smaller decentralized wastewater treatment systems As these decentralized wastewater treatment systems become more common it will be important to apply state of the art technology to ensure that adequate performance is maintained at reasonable cost This study was carried out to identify issues with the use of real time remote monitoring of decentralized wastewater facilities and to provide information on what is required to increase the use of this technology The study included a literature search case study review and information from vendors in the U S and select international sources The study identified the main parameters to be monitored for decentralized wastewater treatment facilities It also identified that the main issue with sensors for these parameters is likely to be maintenance requirements A review of communication options shows that there are many factors in determining the type of system to implement the method of communications the remote control and alarming methodology and the data collection storage and archival methods All of these items must be factored in when determining what type of SCADA system to deploy After reviewing

    Original URL path: http://www.decentralizedwater.org/research_project_DEC2R06.asp (2016-05-01)
    Open archived version from archive


  • decentralizedwater.org
    western Washington Meadow on the Hylebos that incorporates low impact development LID stormwater management practices LID practices used in the project design include bioretention swales permeable concrete compost amended soils and surface flow dispersion The primary goals of the monitoring effort are to evaluate the performance of individual LID practices and evaluate the effectiveness of integrating these practices into a stormwater management system Continuous simulation modeling Western Washington Hydrology Model

    Original URL path: http://www.decentralizedwater.org/research_project_04-DEC-11SG.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    larger research project to assess soil treatment unit STU performance in treating important wastewater constituents Data were compiled from published field and laboratory studies relevant to fate and transport in soil of nitrogen N phosphorus P microbial pollutants and emerging organic wastewater contaminants OWC The literature review also identified current best practices for using models and other tools to predict STU performance The review demonstrates the variability of data collected at different field sites and suggests that simple binary relationships e g the ratio of a contaminant in soil to that in effluent C Co versus depth for various soil types cannot accurately predict the attenuation of wastewater constituents in soil In addition many of the parameters that effect contaminant fate and transport in soils are not measured in available field studies Most models for N and P fate and transport have been developed for agricultural applications rather than for soil treatment of wastewater However the CW2D model contains many of the transformation processes relevant to STU performance and it may be possible to adapt the model for that use Attempts to model microbial transport in soils have been hampered by the current incomplete understanding of the role of soil

    Original URL path: http://www.decentralizedwater.org/research_project_DEC1R06.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    screening models and GIS screening models as well as complex numerical models that include groundwater models vadose zone models surface water models and integrated watershed models They provide guidance on model selection obtaining model input and calibration data model parameterization model sensitivity analysis model calibration and long term model care They describe use of model results for risk based decision making Case studies demonstrate how the methodologies presented in the

    Original URL path: http://www.decentralizedwater.org/research_project_04-DEC-6.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    As the accumulation commences the effect of slowed wastewater flow exacerbates the rate of accumulation and deposit of FOG materials onto the pipe walls thereby reducing capacity The primary means of controlling FOG blockages is to capture and retain FOG materials before discharge into sewer systems through the use of passive grease interception devices Limited scientific studies have evaluated the performance of these devices Many claims of enhanced performance made by manufacturers of grease and oil interception devices need to be verified by objective and unbiased research protocols The final report Assessment of Grease Interceptor Performance presents the evaluation of field grease interceptors through their separation and cleaning cycles In addition researchers performed controlled laboratory scale grease interceptor tests and numerical simulations to assess removal efficiency by grease interceptors GI at different residence times and under different geometric configurations Numerical simulations included a 3 D multi phase flow model of a grease interceptor to evaluate design changes and operation and maintenance conditions on the removal of FOG from foodservice waste streams The results from experimental tests performed on lab scale grease interceptors were used to validate the model results A second report the Fog Interceptor Design and Operations FOGIDO Guidance

    Original URL path: http://www.decentralizedwater.org/research_project_03-CTS-16T.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    jurisdiction Due to their age and condition many of these systems may soon require upgrading or replacement to meet current requirements Adding to the need to compile good quality performance data for large scale decentralized systems is the perception that property developers frequently arrange for wastewater service that results in the least short term investment rather than the lowest life cycle costs Such choices are likely based largely on the absence of readily available information that could help with that decision making process By contrast centralized systems are often at least partially planned funded and managed by utilities that are ultimately accountable to rate payers who provide an accompanying driver to minimize life cycle costs Far more operations and performance data has been compiled and made available to the public for larger centralized systems This nationwide study has gathered data information for and examined the performance of large scale decentralized and small community wastewater systems with flows ranging from 5 000 to 50 000 gallons per day with at least five years of operating history The study covers systems handling domestic waste flows only residential and commercial facilities that have been designed and constructed in accordance with regulatory requirements and

    Original URL path: http://www.decentralizedwater.org/research_project_04-DEC-9.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    performance is critically important to the overall functioning of decentralized wastewater systems Current primary unit design and operational practices tend to be driven by highly prescriptive regulations industry standards and guidance materials which rely on limited and often dated scientific information and past practices and may be incomplete in their consideration of the factors that may influence primary treatment unit performance in decentralized wastewater systems Although septic tanks and grease traps are generally robust and efficient primary treatment units the optimization of their design and operation has been limited Further research may be warranted to answer outstanding questions and optimize practices however it should be conducted within the framework of overall decentralized system performance objectives and functions The objective of this project was to take a fresh look at the existing body of work addressing the performance of primary treatment units in decentralized wastewater systems with a goal of establishing what is known what is not known and what future research may be warranted Design construction installation and operation monitoring and maintenance issues were each considered with a focus on those factors most likely to affect primary unit treatment objectives including influent characteristics sizing hydraulic design compartmentation influent and effluent appurtenances and seasonal effects among others Relevant publications were thus identified compiled analyzed and synthesized with important research recommendations defined to support the development of several interrelated products designed to be useful tools for WERF subscribers practitioners researchers policymakers and other stakeholders Research Digest Bibliographic Database 3 Communications Documents Technical Guide This six page bulletin concisely communicates the main technical findings of the project It primarily targets designers engineers regulators and educators but other stakeholders may use the guide to further their knowledge in the subject Program Points This fact sheet will be useful to policymakers as it communicates the

    Original URL path: http://www.decentralizedwater.org/research_project_04-DEC-7.asp (2016-05-01)
    Open archived version from archive

  • decentralizedwater.org
    poorly developed Research on the performance of North American green roofs has really only been done for the last decade and although we have learned much there are still many unanswered questions There is ample evidence that green roofs can reduce stormwater runoff in Eastern North America by 40 60 but the relative contribution of the media and plants to this stormwater retention has not been characterized or quantified Further for this retention and evapotranspiration to be of use to stormwater engineers and developers tools to predict the retention and detention of stormwater on a green roof are needed This project describes studies of the evaporation and evapostranspiration of water from green roof modules planted with three common green roof plant species Green roof plants like sedum and delosperma used water quickly when it was available and reduced their water use rate when they were drought stressed This makes sedums and delosperma ideal plants for green roof use Plants contribute as much as 40 of the roof capacity to retain stormwater depending on the frequency and intensity of the storm events This data and other runoff data from larger field study roofs provided the basis for models that describe and predict the function of a green roof described in this report In addition to influencing the quantity of runoff greenroofs can also influence the quality of runoff One of the most consistently reported benefits of a green roof for runoff quality is the neutralization of acid precipitation It is clear however that this is a finite property of the medium controlled by the potential buffering capacity of the medium To maintain this capacity and hence the water quality benefit greenroof maintenance should include periodic liming to replace the neutralized media buffer This project describes the buffer potential of two commercial

    Original URL path: http://www.decentralizedwater.org/research_project_04-DEC-10SG.asp (2016-05-01)
    Open archived version from archive



  •