Greywater IQP Report

The goal of this project was to help advance Dar Si Hmad\u27s fog water harvesting project in the Aït Baâmran region of Morocco by designing a greywater recycling system to capture and re-use water at the household level. Accounting for cultural and environmental factors that could hinder the adoption of water recycling, our group developed a guide outlining three potential greywater recycling techniques and proposing a greywater recycling system for the Dar Si Hmad test house

An Investigation of Engineering Decision-making in a California Clean Water Grant Project

The planning and design of an engineering project can be viewed as a series of decisions. It follows , therefore , that a project is well engineered when good decisions are made in an efficient manner. This investigation seeks to examine engineering decision making for the general purpose of providing insights which may improve the engineering decision-making process. The study centers around a project constructed under the Clean Water Grant Program in California. There are two reasons for this 1) the Clean Water Grant Program is presently (1979) the largest public works program in the United States and is therefore, significant to the field o f civil engineering in general, and 2) the author has worked in the program for several years. Despite the choice of a Clean Water Grant project, the investigation is, in most respects, illustrative of engineering decision -making in general and applicable to other types of projects. The first part of the investigation is an overview of engineering decision-making . Utilizing the literature, as well as examples from other Clean Water Grant projects, various bases on which decisions are made are explored considering also, some psycho logical aspects and philosophical implications of engineering decision-making. Also, some special too ls and approaches current in the engineering field are discussed. The second part investigates, in detail, the planning and design of wastewater facilities for the City of Taft, California. Its purposes area 1) to survey all decisions made in ·the planning and design of the project; and 2) to identify and discuss the basis of the decisions. The Taft project was selected for study for several reasons: 1) the limited scope of its design allowed the design decisions to be identified without becoming unwieldy; 2) it is typical of Clean Water Grant projects in many respects; 3) the planning and design were exceptionally well done; and 4) there were interesting and uncommon features to the project, especially in the planning phase. In addition, the project engineer was willing to discuss candidly the basis of the decisions in this project. This is in contrast with engineers on other projects, who, when approached by the author, were very reticent to discuss the true basis of their decisions. Finally, the author\u27s direct involvement in the project, by way of his duties working for the State Water Resources Control Board, greatly facilitated the investigation

Mathematically formulated key performance indicators for design and evaluation of treatment trains for resource recovery from urban wastewater

While urban wastewater infrastructure is aging and no longer adequate, climate change and sustainability are urging the transition from pollution management to resource recovery. Lacking evidence-based quantitative evaluation of the potential benefits and consequences of resource recovery from wastewater hinders the negotiation amongst stakeholders and slows down the transition. This study proposes mathematical formulations for technical, environmental, economic, and social key performance indicators (KPIs) that can be used to quantify the benefits and the risks of resource recovery. The proposed formulations are derived from the literature and validated with stakeholders. Each KPI is mathematically formulated at treatment train level by considering: (1) the characteristics of individual unit processes (UPs) in the treatment train (TT), (2) the context in which the TT is installed, and (3) the resources to be recovered. The mathematical formulations of the KPIs proposed in this study enable a transparent, consistent and informative evaluation of existing treatment trains, as well as support the (computer aided) design of new ones. This could aid the transition from urban wastewater treatment to resource recovery from urban wastewater.</p

Water Scarcity, Marketing, and Privatization

Most Americans take water for granted. Turn on the tap and a limitless quantity of high quality water flows for less money than it costs for cable television or a cell phone. The current drought has raised awareness of water scarcity, but most proposals for dealing with drought involve quick fixes-short-term palliatives, such as bans on washing cars or watering lawns except on alternate days. It is assumed that things will return to normal, and we will be able to wash our cars whenever we wish. But the nation's water supply is not inexhaustible. A just-released report of a White House subcommittee ominously begins: "Does the United States have enough water? We do not know." In a survey of states conducted by the U.S. General Accounting Office, only 14 states reported that they did not expect to suffer water shortages in the next 10 years. Is the sky falling? Not yet, but the United States is heading toward a water scarcity crisis: our current water use practices are unsustainable, and environmental factors threaten a water supply heavily burdened by increased demand. As the demand for water outstrips the supply, the stage is set for what Jared Diamond would call a collapse. How will we respond? When we needed more water in the past, we built a dam, dug a canal, or drilled a well. With some exceptions, these options are no longer viable due to a paucity of sites, dwindling supplies, escalating costs, and environmental objections. Instead, we are entering an era in which demand for new water will be satisfied by reallocating and conserving existing sources. The current water rights structure is the outcome of historical forces that conferred great wealth and power along with the water. The solution to tomorrow's water shortages will require creative answers to challenging issues of equity, community, and economics

Once despised now desired: innovative land use and management of multilayered Pumice Soils in the Taupo and Galatea areas, central North Island, New Zealand

The tour brings together innovative land use change and management associated with dairy farming, and land-based effluent disposal, on weakly weathered and multi-layered, glass-rich, Pumice Soils (Vitrands) in the Taupo and Galatea areas. These changes and their effects, together with environmental and sustainability issues, form a central theme of the trip. Four main stops are planned, two before lunch and two after: (1) plantation pine-to-dairy farm conversion and impacts, the Taupo eruption deposits (AD 232 ± 10) and the Taupo soil, at Tahorakuri; (2) overview of the application of secondary-treated wastewater and nitrogen leaching and uptake, Rotokawa; (3) a sequence of five Holocene tephras and buried soils, including Kaharoa eruption deposits (AD 1314 ± 12) and the Galatea soil, Smeith Farm, Murupara; and (4) enhancing pasture production on ‘new’ soils formed by excavating and mixing (‘flipping’) buried soil horizons (paleosols) on Smeith’s farm. During the trip − which helps mark Waikato University’s 50th anniversary − we will see a spectacular range of volcanic and fluvial landscapes and deposits, together with impacts of tectonism, as we traverse the famous Taupo Volcanic Zone ((TVZ) in the central volcanic region. Landforms and soils dominated by tephras (volcanic ash) become generally younger towards the loci of volcanic activity. Extensive areas of soils have been formed repeatedly from the fragmental eruptive products of the two most frequently active and productive rhyolite (silica-rich) volcanic centres known, namely Taupo and Okataina. Thus soil stratigraphy and upbuilding pedogenesis form a second theme on the trip. The first part of the guidebook thus contains sections including (i) volcanism and its products, (ii) Quaternary volcanism in TVZ including deposits erupted recently from Taupo and Tarawera volcanoes from which Pumice Soils have been formed, (iii) tephra-derived soils including Pumice Soils, their classification, special problems, and (low) fertility, (iv) allophane and its formation, and (v) the interplay between geological and pedological processes relating to tephras (upbuilding pedogenesis). The second part then comprises notes and illustrations pertaining to each stop (note that figure and table numbers are self-contained at each stop, or not used). Broad overviews of the region’s geology are covered by Leonard et al. (2010), and the soils are outlined by Rijkse and Guinto (2010) and S-map. Further compilations of data are available in tour guides by Lowe (2008) and Lowe et al. (2010)

Modeling for optimal management of agricultural and domestic wastewater loading to streams

A simulation/optimization (S/0) model to aid managing multiobjective wastewater loading to streams while maintaining adequate downstream water quality is presented. The conflicting objectives are to maximize the human and dairy cattle populations from which treated wastewater can be discharged to the river system. Nonindustrial municipal (domestic) wastewater undergoes primary and secondary treatment by a sewage treatment plant (STP) before entering as a steady point source. Dairy wastewater is treated by overland flow (OLF) land treatment before entering the stream as a controlled steady diffuse source. Maximum dual-source loading strategies which do not degrade downstream water quality beyond specified limits are developed. For each computed loading strategy, an optimal OLF system design is also determined. The E constraint method is used to obtain sets of noninferior solutions. Sets of noninferior solutions are represented graphically to show the trade-off between human and bovine populations that can be maintained. Each set is computed for a different upstream flow rate to illustrate sensitivity to nondeterministic upstream flow rates. The nonlinear constraints utilized restrict downstream concentrations of 5-day biochemical oxygen demand, dissolved oxygen, nitrogen (organic, ammonia, nitrite, and nitrate), organic and dissolved phosphorus, and chlorophyll a. Concentrations are described via regression equations. The new regression expressions, surrogates for the complex advective-dispersive equation, permit rapid and feasible solutions by this unique S/0 model

Invited review: Models for the optimization of regional wastewater treatment systems

European Journal of Operational Research, nº 73 (1994)The problem of the optimization of regional wastewater systems may be generally formulated as follows: to define the transport and treatment system, in a region or water basin, which assure compliance with given pollution control criteria, with minimum cost. In addition, one may try to satisfy other objectives, such as minimum environmental impact, better effluent reuse or adequate phasing. From the optimization point of view, the two main problems that render the solution difficult are the dimensionality and the concavity of cost functions. The matter has been dealt with by many authors, who have produced varied techniques to try to solve this problem. This paper begins with a brief review of the work of those authors who have produced models specifically designed to study the problem. Then, solution strategies are discussed concerning three major items: definition of the objective function and constraints, optimization method and practical aplicability of the models. The paper concludes with the discussion of topics for future research

Water supply and demand

Water supply / Water demand / Water management / Water policy / Sri Lanka

Evaluation of the Potential for Ecological Treatment Technologies to Remediate Species of \u3ci\u3ePhytophthora\u3c/i\u3e from Irrigation Runoff

Increased incidences and severity of drought have reduced reliable access to freshwater sources for irrigation purposes by nursery and greenhouse plant producers. Many plant producers are now considering onsite remediation and reuse of water captured from irrigation runoff. However, potential contamination of recycled water with plant pathogens, primarily species of Phytophthora, is the primary concern preventing many growers from reusing their water. Species of Phytophthora are capable of infecting thousands of host plants and cause some of the most economically important diseases of nursery and greenhouse crops worldwide. Phytophthora spp. produce motile, swimming zoospores that often serve as propagules of dispersal and often are the primary infective propagules that initial infections on many plants. While many chemical and physical treatment methods are currently used to disinfest recycled irrigation water, there are many drawbacks to using these technologies. Biological methods for managing Phytophthora spp. in waterways, including bioreactors and constructed wetlands, are not as widely implemented and are not well understood. The overall goal of this dissertation was to assess the potential of passive biological and ecological treatment technologies to remediate Phytophthora spp. from irrigation runoff at nurseries and greenhouses, so treated irrigation runoff may be reused on site. Through a series of greenhouse experiments, we determined that the following plant species may be susceptible to the species of Phytophthora indicated: Carex stricta (P. cinnamomi and P. cryptogea), Panicum virgatum (P. nicotianae), and Typha latifolia (P. cinnamomi, P. cryptogea, and P. nicotianae). Agrostis alba, Iris ensata \u27Rising Sun\u27, and Pontederia cordata plants did not appear to be susceptible to the species of Phytophthora tested during this study; therefore, they may be suitable for use in constructed wetland systems. Using a controlled model floating treatment wetland (FTW) system, we determined that FTWs established with Pontederia cordata plants reduced the flow-through of viable Phytophthora nicotianae zoospores as compared to control units containing no FTW at a target hydraulic retention time (HRT) of 4 h. Finally, we determined that laboratory-scale bioreactors containing fir bark reduced flow-through of P. nicotianae viable zoospores as compared to control units that did not contain any substrate, during low and high input nitrogen concentration conditions (11.6 ± 0.3 mg/L N and 72.0 ± 3.7 mg/L N, respectively) and at flowrates equivalent to a target 2 h and 8 h HRT. These are the first studies to evaluate the efficacy of small-scale FTWs and agricultural bioreactors to manage Phytophthora species in water and some of the only studies to evaluate ecological technologies for plant pathogen remediation at representative field hydraulic conditions. Future studies should investigate the biogeochemical transformations of nutrients and associated microbial communities within ecological remediation systems to gain further insight into the potential of microbiologically aided removal mechanisms. Interdisciplinary approaches such as this one—which involve teams of agricultural engineers, plant pathologists, plant scientists, and hydrologists—will be crucial for future studies seeking to understand the aquatic ecology of plant pathogens and potentially novel ecological methods for remediation. Increased confidence in and implementation of ecological treatment technologies will enable producers of greenhouse and nursery crops to safely, economically, and sustainably remediate runoff and drainage waters onsite so that they are able reuse this water for irrigation purposes. Recycling water will help agricultural producers gain access to a reliable water source at a time when access to surface and ground waters is becoming increasingly scarce and contentious due to overuse and increased incidence and severity of droughts