Coarse particulate organic matter (CPOM) is an essential part of the food chain in aquatic ecosystems because it represents a readily available carbon and energy source. The process by which it decomposes in rivers has been well studied and documented. However, the rate and extent of biodegradability of various CPOM components (i.e., twigs, leaves, grass, etc.) in storm drains is not well understood. The Jordan River TMDL study identified storm water generated CPOM as a likely cause of low dissolved oxygen levels in the lower Jordan River, but recent investigations have suggested that dissolved organic matter generated from this CPOM in storm drains and culverts entering into the Jordan River, rather than the CPOM itself, is the main driver of oxygen impairment. The degradability of CPOM components transported and stored in the storm drain system was studied to understand its relative impact on dissolved oxygen and nutrient status in the Jordan River. Results indicate the generation of highly degradable organic material is a function of the starting CPOM, and oxygen consumption is associated with the dissolved portion of organic material leached from CPOM in water. Leaves and grass produced the highest levels of all parameters studied. Between 93% to 95% of total oxygen demand is generated within the first 1 to 3 hours of the 24 hour test. Chemical oxygen demand and dissolved organic carbon proved to be the best indicator of biochemical oxygen demand. By using the results of the leaching study an estimate of water quality indicator levels in the Jordan River was made, and was compared to levels in samples collected from the Jordan River. The estimate proved accurate for dissolved organic carbon but not for total or volatile suspended solids. Results of this study were used to discuss possible solutions to reduce oxygen demand in the Jordan River.

Enligt Svenskt Vatten ska dagvattensystem vara dimensionerade för att klara ett regnmed en återkomsttid på 10 år. För att utvärdera om ett system är rätt dimensionerat kanen dagvattenmodell upprättas. Det är då viktigt att veta vilka nivåer ledningarna har mendenna information är bristfällig hos många kommuner. Ledningarna borde dock följatopografin i generella drag och borde därför kunna uppskattas därifrån.Syftet med denna studie var därför att utveckla en metod för hur vattenledningarnasnivåer kunde ansättas på ett enkelt sätt utifrån marknivån och hur stor betydelse detskulle ha vid dagvattenmodellering. Ett ytterligare syfte var att även bedöma Lidingöstads dagvattensystem, där information om ledningarnas nivåer saknades, utifrån dennametod. För att metoden skulle vara användbar var det också viktigt att den var enkel attapplicera även för stora dagvattensystem.Delar av Sundbybergs dagvattennät i Stockholms län användes för att utvecklametoden. Där var ledningarnas nivåer kända och en analys av detta resulterade i enmetod där brunnarnas djup, som styr ledningarnas nivåer, ansattes på 2 m djup. Ettundantag var tvunget att göras vid de fall då ledningarna fick bakfall. Där ansattes ettdjup så att ledningen låg horisontellt.Vid utvärdering av hur stor påverkan ansättningen av djupet hade togs hänsyn tillosäkerheten av avrinningskoefficienten genom att använda tre olika scenarier;oförändrad, 30 % lägre samt 30 % högre avrinningskoefficient. För varje brunn vägdesrisken för översvämning ihop från resultatet av dessa tre scenarier och sammanställdesmed att varje brunns trycknivå fick status över mark, under mark eller osäker. Dettagjordes för både modell med kända och med ansatta nivåer. Statusen för varje brunnjämfördes sedan dem emellan för att utvärdera hur bra metoden för att ansättabrunnarnas djup var.Resultatet av studien visar att metoden i stora drag gav samma resultat vad gäller riskenför översvämning jämfört med om nivåerna hade varit kända. Avvikelser uppstodfrämst vid diken men även för enstaka instängda områden och utlopp. För Lidingösdagvattennät hamnade trycknivån för 18 % av brunnarna över marknivån vid ett 10-årsregn och ytterligare 16 % var osäkra. / According to The Swedish Water and Wastewater Association (SWWA), a storm waternetwork must be able to handle a rainfall with a return period of 10 years. In order toevaluate whether a drain system is adequately dimensioned, a storm water model can beestablished. This requires knowledge about the levels at which the conduits are situated,and this information is insufficient in many areas. However, the pipes could largely beassumed to follow the topography and the pipes levels can be estimated from it.Therefore, the aim of this study was to develop a method for how the level of stormwater conduits could be assessed from the ground level, and the significance thismethod had for storm water modeling. A further aim was also to, according to thismethod; assess the storm water systems of the Lidingö community, which lackedinformation on the pipe levels. Furthermore, for the method to be useful it wasimportant to make it easily applicable even to large storm water networks.The method was developed using parts of the storm water network in Sundbyberg,Stockholm. The levels of the conduits were known beforehand, and an analysis of themresulted in a method where the depth of the manhole, which controls the levels of theconduits, was estimated to 2 m. An exception had to be made when the conduits were inreverse slope, in which cases horizontal slope was assumed.When evaluating the impact from the depth assessment on the runoff, the uncertaintyfrom the imperviousness was taken into account by using three different scenarios;unchanged, 30% lower and 30% higher imperviousness. The risk of flooding for eachone of the manholes was weighted from the results of these three scenarios. Thisresulted in a pressure level for each manhole, either above ground, below ground orinconclusive. This was done for the model with both known levels for the conduits, andwith the assessed levels. In order to evaluate how well the method for applying thedepth worked, the status of each manhole was compared between the two models.The conclusion from this study was that the method developed here, more or less gavethe same results as when the levels of the conduits were previously known.Discrepancies arose mainly in ditches, but also for a few landlocked areas and outlets.For the Lidingö storm water network, 18 % of the wells ended up with a pressure levelabove ground when applied to a rain with a 10 year return period. Another 16 % of thewells were inconclusive.

This current study is a lab-scale investigation focused on the treatment of stormwater runoff generated in wood-storage areas. The main target constituents of the proposed treatment were: metals (Cu, Cd, Co, V, Pb, Zn, Ni, Cr, Fe, As), COD, TOC, Phenols, and color. The method implemented for this project follows the main concept of using low-cost and environmentally friendly technologies and had as main steps the use of a by-product of wood-based industries - wood fly ashes as sorbents - followed by oxidation with H2O2 (Hydrogen Peroxide). The results obtained during this investigation were vey promising since satisfactory removal % was achieved. Removal rates of 98.5%, 86%, 89.6%, 79.6% were achieved for color, chemical oxygen demand (COD), total organic carbon (TOC) and phenols respectively. Furthermore a decrease in metals concentrations was also observed with the exception of chromium. The study showed that for 300 ml storm water, optimum conditions were with 7g wood fly ash, 5 hours time reaction, pH≈11.46 and 150 μl of a 30% H2O2 solution in a room temperature. To conclude it can be stated that the use of a by-product from wood industry to treat contaminated water from the same sector, following the concept of a closed-loop system, is promising and possible. However further studies need to be conducted in order to evaluate such system in scaled-up conditions.

Aogu Farm was built on reclaimed land. Because of its rich ecological resources, Aogu was defined as a "Major Wildlife Habitat" in Chiayi County by the Forest Service and is also expected to reduce carbon in the plan for the flatland forest. Power pumps are currently used to irrigate and cultivate the area. However, after becoming the Forest Recreation Area in the future, Aogu Farm has to reduce the influence of human beings. However, if the Taisugar Company doesn¡¦t support the plan of Forest Service or abandons farming and stops the pumping power, the Aogu Wetlands will suffer the crisis of coastal inundation. Hydrological models have their own characteristics. For example, inundation models for regional drainage using one-dimensional channel flow, two-dimensional overland flow, and runoff in the mountains all can be assessed to solve the inundation problems in the coastal lowlands. Nevertheless, the Aogu Wetlands, the Case Study area, has both a dry season and a wet season even in the lowland. When rainstorms occur, the area is unable to discharge the water by gravity but can depend only on pumps to discharge the water into the sea. Therefore, based on the need to manage water, hydrological surveys must be conducted to assess the hydrological impact of continuous rainfall on the Aogu Wetlands and to provide reference information to assist in the management. In the thesis, I use both the Geographic Information System (GIS) and the Storm Water Management Model (SWMM) as analysis tools. Moreover, the different regions are further divided into watershed and the route of drainage, establishing two kinds of models of watershed hydrology for precipitation simulations. Finally, to compare these two methods, the Arc Hydro and SWMM models are used in watershed analysis.

Land development transforms the natural landscape and impacts in stream ecosystems and downstream communities as it alters the natural flow regime. An increase in impervious areas results in higher volumes of storm water runoff, reduced time to peak, and more frequent flooding. Best Management Practices (BMP) and Low Impact development (LID) are a few of the set of measures which are used to mitigate the impact of urbanization. Peak flow, runoff volume are few of the conventional metrics which are used to evaluate the impact and performance of these storm water management strategies on the watershed. BMP are majorly used to control the flood runoff but results in the release of large volumes of runoff even after the flood wave passed the reach and LIDs are used to replicate the natural flow regime by controlling the runoff at the source. Therefore need to incorporate a metric which includes the timing and area being inundated needs to be considered to study the impact of these strategies on the downstream. My proposed research will focus on simulating the Low Impact Development (LID) techniques like permeable pavements and rainwater harvesting on an urbanized watershed using a curve number approach to quantify the hydrologic performance of these strategies on the watershed. LID, BMPs, and combined strategies are introduced for retrofitting existing conditions and their hydrologic performance is accessed based on the peak flow and a new metric Hydrologic Footprint Residence. A simulation optimization framework would be developed which identifies cost effective LID options that maximize the reduction of peak flow from the existing condition design storms while meeting budget restrictions. Further LID and BMP placement is included in the optimization model to study the impact of the combined scenario on the storm water management plans and their performance based on different storms and corresponding budget. Therefore a tradeoff can be illustrated between the implementation cost and the hydrological impact on the watershed based on the storm water management approach of using only LID and combination of LID and BMP corresponding to varied spectrum of design storm events.

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Drainage area is a measure of the number of acres feeding into a creek. Drainage area threshold is the amount of acreage required for the creek to be included on a map. Watersheds mapped according to higher drainage area thresholds will show creek systems that are shorter and concentrated at the bottom of the watershed. Watersheds mapped according to lower drainage area thresholds show creek systems that are longer and extend further up the watershed. Since all watersheds are subject to different land uses, soil types, geology, etc., they should be mapped according to different drainage area thresholds. Headwaters are where creeks begin. There is empirical evidence that properly functioning headwaters significantly reduce erosion, improve water quality, slow stormwater flows, and provide habitat. If municipalities use lower drainage area thresholds to define their creeks, they can include more headwaters in their creek setback requirements. This professional report identifies the Harris Branch watershed as being under relatively more pressure to develop and exhibiting more environmental risk than other watersheds in Austin, Texas’ Desired Development Zone. Creeks in the watershed are redrawn according to reduced drainage area thresholds using a simple ArcGIS analysis. The analysis reveals a critical mass where creek setbacks appear to be too extensive. If creeks with a drainage area of 5 acres are protected by development code, the setbacks created have excessive branching that could be too restrictive for development. A critical mass ratio should be considered when determining which drainage area threshold is most appropriate for a watershed. The critical mass ratio is equal to the number of branches allowed per a specified distance of creek centerline. The process of identifying this critical mass ratio can help growing cities find a balance between the need to encourage development in designated areas and the need to protect natural creek systems everywhere. I recommend that municipalities review the effects of reducing drainage area threshold for each watershed, and then identify the drainage area threshold that, when protected by setback requirements, allows for extended and connected greenways as well as an increase in density. / text

This thesis proposes an architecturally integrated stormwater system and research facility in the town of Wasagaming, Riding Mountain National Park (RMNP), Manitoba. The design proposal provides four-season, interior and exterior space for the integration of resource management operations and park visitor experiences. Visible integration of infrastructure, building and landscape cultivate destination-based travel to RMNP while reducing human impacts on the ecosystem. Aging infrastructure and diminishing federal funding make responsible ecological and cultural management of parks increasingly difficult. Integration of research and tourism as a component of visitor experience at parks is one way of addressing cost-effective co-location of programme, ensuring future funding can be generated for resource management.

In this study, a two phase investigation of the hydraulic conductivity parameters of silty soils was performed. In the first phase, double-ring infiltrometer tests were used to measure infiltration rates in-situ at two sites in the Piedmont physiographic province of Georgia. The efficacy of predicting saturated hydraulic conductivity for Piedmont soils via published soil surveys from the National Resource Conservation Service and pedotransfer functions was then investigated. Work focused on the development of a consistent test methodology for soils (sandy, to silts and clays) in the Piedmont, and the final test method utilized being the constant head test, using a double-ring infiltrometer with Mariotte tubes to maintain the head. In the second phase of the investigation, laboratory based measurements of the saturated hydraulic conductivity of binary mixtures of fine sand and nonplastic silt were performed to investigate the effects of particle mixtures on hydraulic conductivity. The materials used were ASTM 100/200 sand and Sil-Co-Sil 40 non-plastic silt, chosen based on the ratio of the mean particle diameters. Significant effort was invested in the development and comparison of methodologies to produce uniform specimens of the binary mixtures for hydraulic conductivity testing, with the final being modified dry tubing. Two fixed densities were used to investigate the effects of particle packing on the hydraulic conductivity of binary mixtures, with critical fines contents chosen to ensure the finer particles primarily filled the pore volume of the coarse particles. Incremental fines contents, by mass, up to this theoretical fines content were tested. The measured saturated hydraulic conductivity was evaluated in terms of fines content, global and intergranular void ratio, and confining stress. Models for predicting extreme void ratios and saturated hydraulic conductivity of binary mixtures were also investigated.

Thesis (M.Eng.Sc)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2000? / Bibliography :leaves 158-171. A monitoring program, funded by the South Australian government (through the former MFP Development Corporation), was established to monitor the quality and quantity of storm water entering and leaving the wetland. This study formed part of the funded program. Simple regression models were developed; and will assist in the monitoring of performance of the wetland to alleviate the pollutant load into the Barker Inlet.