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Climate change effects have been documented in the Canadian Prairie Provinces. Temperature is predicted to continue to increase, and precipitation patterns are changing. As a result, river flow is anticipated to diminish. The South Saskatchewan River (SSR) provides vital habitat to lake sturgeon. Lake sturgeon are currently endangered or threatened across most of their native range, prompting provincial governments to develop management strategies. As lake sturgeon habitat is dependent on flow, understanding climate change impacts on flow conditions in the SSR will be an important component of their long-term management strategy for lake sturgeon. I have developed empirical models based on regional climate variables (temperature and precipitation) to predict in-stream flow. These models were developed using general linear modeling and Akaikes Information Criterion (AIC). Future in-stream flow was predicted by extracting key variables from 5 different GCM’s and inserting the variables into the predictive flow models. These future flow scenarios were coupled with habitat suitability indices developed to assess changes in sturgeon habitat developed by the Water Security Agency and Department of Fisheries and Oceans Canada. Flow scenarios predict a decrease in the habitat of most life stages (spawning, juvenile, adult and subadult), but an increase in fry habitat. These models will represent a novel advancement for sturgeon management in Western Canada.

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The aims of this work are to improve the understanding of the way in which a river system approaches equilibrium during and after sediment transporting events and by using experimental data and hypothetical models to gain an insight into mixed grain sized transport and its connection with local bed morphology. Large scale flume experiments were undertaken in a trapezoidal channel where a mixed grain sized river bed is subjected to a variety of imposed sediment loads. The river system was allowed to adjust naturally to the imposed conditions while flow and bed conditions were frequently monitored. Changes to both flow and bed occur at many scales and the superimposition of these changes adds to the complexity of the interpretation of hydraulic and bed data. Three experiments are reported in which the sediment influx differ. One in which no material is added. One in which a feed rate is established equal in magnitude to 50% of the initial transport rate for the equivalent non-fed case. In the third experiment the feed rate is doubled to 100% of the initial transport rate in the degradation experiment. The imposed load is continued for approximately 75% of the duration of the run or until a dynamic equilibrium transport rate is evident within the reach. The river channel is analysed at two distinct scales; grain scale and reach scale. Conclusions about the relative influence of grain and form effects are drawn on the basis of detailed surface texture information and reach scale measurements of the bed surface. A hypothetical model is proposed to show that the transport activity during a degradation experiment can be qualitatively linked to a wave like translation of grain dislodgement through the channel.

The agricultural sector and communities in the lower Red River Valley in Manitoba have suffered a number of water related problems since the Basin was first settled. Initially a massive drainage system had to be constructed to render much of the area suitable for agricultural production. Major floods and droughts have also plagued the area, resulting in direct measurable costs to area residents and businesses. In a more direct manner, the development of the area has been adversely affected by limited supplies of potable water, and due to a lack of irrigation water, the area has not been able to realize its full development potential. These problems became particularly acute between 1965 and 1980. During this period major Red River floods occurred in 1965, 1966, 1969, 1974, 1975, 1978 and 1979. In the sixty-five years previous to this period, there were only three major floods. Major drought occurred most recently in 1973, 1974, 1977 and 1980. Inevitably there was a public outcry for senior levels of government to initiate preventive action rather than merely providing compensation for losses. However, government has been slow to respond resulting in public frustration and disaffection. This study can be divided into three sections. The first four chapters deal primarily with the history of water management, tracing the evolution of policy and attitude, the transfer of responsibility from local government to more senior levels of government, and the evolution of institutional and methodological obstructions to resolving some of the recurring water management problems. The next four chapters examine the current situation in terms of potable water supply, the advantages and disadvantages of large scale irrigation and the controversy over solutions to flooding. The last chapter is comprised of a summary and recommendations. A common theme throughout the paper is the fact that regional economic development is the ultimate goal of water management. However, policy decisions seem to have devolved from the elected representatives of the people to the technocrats, thereby limiting public recourse to unsatisfactory decisions. The technocrats' approach has been to disassociate development from water management due to an over-reliance on benefit-cost analysis of site-specific, problem-specific issues. In view of the fact that public input is limited and the public perceives government action as wholly inadequate, this paper seeks to empower people to act.

This creative project has taken the form of a 16 millimeter color documentary film that analyzed the proposed alteration of a major natural resource in Indiana; i.e., the Wabash River. The agency responsible for studying the proposed alteration was the U.S. Army, Corps of Engineers, which was acting in response to Congressional authorization.The film analyzed the proposed alteration, known as Wabash Navigation, from the perspectives of history, ecology, economics, and philosophy; differing world views inherent in the global ecological crisis were found to exist in the values of waterway advocates and opponents.The Corps of Engineers found this particular project to be non-feasible. However, the historical and philosophical point is made that non-feasibility does not mean that efforts to promote the waterway would necessarily be dropped. Viewers are asked to analyze the issue from the various perspectives represented in the film and formulate their own opinions.

The use of δ18O- PO4 analysis was assessed for the Grand River, a highly impacted river in Southern Ontario that receives inputs from 30 WWTPs. Significant nutrient inputs within the watershed have led to prolific aquatic plant growth, particularly within the central Grand River where this study is focused. Two of the largest WWTPs in the watershed fall within this region and these plants are in close proximity to each other (approximately 20 km apart). Various laboratory tests were carried out to assess the suitability of several DOM removal methods on Grand River water and WWTP effluent prior to mass spectrometric analysis with varying results. Sample analysis showed all river sites to possess δ18O- PO4 values that were elevated relative to equilibrium. These sites are not equilibrium-controlled and, instead, possess δ18O- PO4 signatures controlled by either source inputs, or isotopic fractionation. The second WWTP was shown to deliver PO43- that was elevated relative to equilibrium. WWTP effluent in this study displayed a large δ18O -PO4 range, ranging from 10.4 to 22.9‰. Most of the variation in isotopic composition was found at the second plant, which had high soluble reactive phosphorus (SRP) and a range of 12.5 to 22.8‰ (n = 3). The first plant showed little variation with much lower SRP and a mean value of 11.4 (SD ± 1.0‰, n = 2). The elevated δ18O- PO4 signatures collected from the second WWTP suggest that this plant is supplying the Grand River with isotopically distinct PO43-. This could be used as a way to establish the effect of the second WWTP on the downstream PO43- pool. Phosphate uptake and release by the epilithon and seston were measured using 32P-PO4 additions in recirculating beaker experiments. Two sites, one downstream of the first WWTP and one below the second WWTP, were assessed for gross and net PO43- uptake rates. The gross uptake rates at both sites were low (0.04 to 0.10 µg P cm-2 h-1), with long turnover times for the dissolved phosphate pool (12 to 40 h). Long uptake lengths (30 to 144 km) were measured, indicating low nutrient retention capabilities downstream of the two WWTPs. These significant P contributions appear to have large-scale effects on the river’s P-kinetics, limiting its ability to act as a net nutrient sink even in the more productive summer months. The biomass response below the WWTPs is insufficient to compensate for the elevated PO43- concentrations and low rates of PO43- uptake. Due to the limited use of δ18O -PO4 analysis in river systems, no model exists for predicting the response of δ18O -PO4 with distance downstream of a point source. Coupling rates of PO43- uptake and release with the effluent δ18O -PO4 values provides such a model and generates guidance for future use of this method in lotic environments. WWTP “plume chases” were previously carried out in the Grand River, and involved measuring SRP at several sites downstream of the WWTP discharge points. SRP was used as a proxy for PO43- concentration in this study, and is operationally defined by what passes through a 0.20-µm membrane filter and is molybdate reactive. Best-fit estimates of PO43- uptake and release were determined using these plume chase events. The rates calculated using the 32P-PO4 uptake and release beaker experiments were up to 50 times lower than the best-fit parameters. This exercise illustrates the unsuitability of relaying estimates of P kinetics collected through beaker experiments to an ecosystem level. Model predictions for the river reach below the second WWTP show that effluent δ18O -PO4 signatures should be observable many kilometres from the plant. Because of the unique mean isotopic composition observed for the second WWTP, sampling could occur at a variety of locations downstream to observe the effect of this plant on the river. The river reach below the first WWTP reduces the incoming P loads much quicker than the second reach, which is in part due to the much lower effluent SRP released by the first plant. It is still possible to isolate effluent derived δ18O-PO4 values downstream of this plant. The return to equilibrium is projected to occur several kilometers from the first plant’s confluence, suggesting the applicability of this method in both stream reaches. It would appear δ18O -PO4 could be a valuable tool for eliciting information on P cycling in effluent-impacted river ecosystems, with the Grand River possessing elevated but seemingly typical uptake lengths amongst eutrophic streams.