Ecological effects of trial pumpings in the Upper Lambourn: Stage 1 group pumping test Upper Lambourn group, September - November 1975

This report to the Thames Water Authority and Central Water Planning Unit is on research carried out in conjunction with the Stage 1 Group Pumping Test of five boreholes in the upper Lambourn Group for a period of three months in September, October and November 1975. The aim of the study was to assess the ecological effects of the pumpin g of five bore-holes in the upper Lambourn. That is, to determine how the seasonal sequence of ecological events in the river differed from what would hav e occurred had no pumping taken place. Since this 'experiment' has no control it is not possible to make a direct assessment. Nevertheless, by careful monitoring of ecological events before, during and after the pumping it is possible to document changes in th e river and by reference to the data already available for the Rive r Lambourn, normal seasonal changes in the flora and fauna can be separated from changes which may be attributable to the pumping and subsequent events.

Interim report on the ground-water resources of Seminole County, Florida

Salt-water encroachment is undoubtedly the problem of most concern to users of ground water in Florida. This is a problem in many coastal areas where water levels are lowered excessively by heavy pumping. It is a problem also in some inland areas where the water-bearing formations contain salty water at relatively shallow depths. Among the coastal areas where wells have become contaminated with salt water are Pinellas County and the Miami area of Dade County. Inland areas where wells are likely to become contaminated with salt water include Seminole County and the southwestern part of Volusia County. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county with special emphasis on the problems associated with declining water levels and salt-water contamination. This report reviews briefly the progress of the investigation through February 1954. (PDF contains 43 pages.)

Interim report on geology and ground-water resources of Indian River County, Florida

In the area of this investigation a partial inventory was made of the estimated 2,000 existing wells to obtain information on location, depth, and yield of representative wells. Also, data were obtained on the quality of water from the various aquifers, and on the fluctuation of water levels in certain wells in the Floridan aquifer. The hydraulic characteristics of the Floridan aquifer at several sites were determined by means of pumping tests. (PDF has 80 pages.)

Seasonal Climatologies and Variability of Eastern Tropical Pacific Surface Waters

Interannual variability caused by the El Nino-Southern Oscillation in the eastern tropical Pacific Ocean (ETP) is analogous to seasonal variability of comparable magnitude. Climatological spatial patterns and seasonal variability of physical variables that may affect the ETP ecosystem are presented and discussed. Surface temperature, surface salinity, mixed layer depth, thermocline depth, thermocline strength, and surface dynamic height were derived from bathythermograph, hydrocast, and CTD data. Surface current velocity, divergence, and upwelling velocity were derived from ship drift reports. Surface wind velocity, wind stress, wind divergence, wind stress curl, and Ekman pumping velocity were derived from gridded pseudostress data obtained from Florida State University. Seasonal maps of these variables, and their deviations from the annual mean, show different patterns of variation in Equatorial (S°S-SON) and Tropical Surface Water (SOlS0N). Seasonal shifts in the trade winds, which affect the strength of equatorial upwelling and the North Equatorial Countercurrent, cause seasonal variations in most variables. Seasonal and interannual variability of surface temperature, mixed layer depth, thermocline depth and wind stress were quantified. Surface temperature, mixed layer depth and thermocline depth, but not local wind stress, are less variable in Tropical Surface Water than in Equatorial Surface Water. Seasonal and interannual variability are close to equal in most of the ETP, within factors of 2 or less. (PDF file contains 70 pages.)

The potential impact of Ocean Thermal Energy Conversion (OTEC) on fisheries

The commercial development of ocean thermal energy conversion (OTEC) operations will involve some environmental perturbations for which there is no precedent experience. The pumping of very large volumes of warm surface water and cold deep water and its subsequent discharge will result in the impingement, entrainment, and redistribution of biota. Additional stresses to biota will be caused by biocide usage and temperature depressions. However, the artificial upwelling of nutrients associated with the pumping of cold deep water, and the artificial reef created by an OTEC plant may have positive effects on the local environment. Although more detailed information is needed to assess the net effect of an OTEC operation on fisheries, certain assumptions and calculations are made supporting the conclusion that the potential risk to fisheries is not significant enough to deter the early development of IDEe. It will be necessary to monitor a commercial-scale plant in order to remove many of the remaining uncertainties. (PDF file contains 39 pages.)

Der Anteil Transportwasser bei Heringsanlandungen mittels Vakuumsauganlage in Großraumbehältern

Estimation of the water content of herring landings caused by pressure-vacuum double tank pumps and using of multi purpose transport containers About 80 % of herring that is landed in the fish processing company Euro-Baltic Fischverarbeitungs GmbH Mukran, on the Isle of Rügen at the Baltic coast is transported from the cutter into the processing plant by pumping. For this purpose 700 l-Euro-size polyethylene tubs (containers) are filled with herring by means of a pressure-vacuum pump-systems during the unloading of the cutter. To be able to pump the fish from the hold on board it is kept floating in water (transport water). At the end of the pumping/transporting process the fish ends in a dewatering box before reaching the tub, where the transport water is separated from the fish. Then, the not completely dewatered fish is slipped into the transport containers. The amount of transport water reaching the containers depends on the type of PV-equipment and on the amount of transport water in the fish holds of the different cutters. Methodologically the mixture of fish and water must be weighed together. For the experiments specially designed transport container were used which allow the measurement of the run-off of the water to be quantified and thus to measure the proportion of water remaining with the fish. Based on 30 experiments it could be shown that on average 6 % of remaining weight of the mixture is water. Furthermore, factors were detected which influence the variability of the proportion of water.

Decision support systems optimising effluent release in sub tropical estuarine environment - An Australian case study

Gold Coast Water is responsible for the management of the water and wastewater assets of the City of the Gold Coast on Australia’s east coast. Treated wastewater is released at the Gold Coast Seaway on an outgoing tide in order for the plume to be dispersed before the tide changes and renters the Broadwater estuary. Rapid population growth over the past decade has placed increasing demands on the receiving waters for the release of the City’s effluent. The Seaway SmartRelease Project is designed to optimise the release of the effluent from the City’s main wastewater treatment plant in order to minimise the impact of the estuarine water quality and maximise the cost efficiency of pumping. In order to do this an optimisation study that involves water quality monitoring, numerical modelling and a web based decision support system was conducted. An intensive monitoring campaign provided information on water levels, currents, winds, waves, nutrients and bacterial levels within the Broadwater. These data were then used to calibrate and verify numerical models using the MIKE by DHI suite of software. The decision support system then collects continually measured data such as water levels, interacts with the WWTP SCADA system, runs the models in forecast mode and provides the optimal time window to release the required amount of effluent from the WWTP. The City’s increasing population means that the length of time available for releasing the water with minimal impact may be exceeded within 5 years. Optimising the release of the treated water through monitoring, modelling and a decision support system has been an effective way of demonstrating the limited environmental impact of the expected short term increase in effluent disposal procedures. (PDF contains 5 pages)

Coastal erosion as a natural resource management problem: An economic perspective

Unremitting waves and occasional storms bring dynamic forces to bear on the coast. Sediment flux results in various patterns of erosion and accretion, with an overwhelming majority (80 to 90 percent) of coastline in the eastern U.S. exhibiting net erosion in recent decades. Climate change threatens to increase the intensity of storms and raise sea level 18 to 59 centimeters over the next century. Following a lengthy tradition of economic models for natural resource management, this paper provides a dynamic optimization model for managing coastal erosion and explores the types of data necessary to employ the model for normative policy analysis. The model conceptualizes benefits of beach and dune sediments as service flows accruing to nearby residential property owners, local businesses, recreational beach users, and perhaps others. Benefits can also include improvements in habitat for beach- and dune-dependent plant and animal species. The costs of maintaining beach sediment in the presence of coastal erosion include expenditures on dredging, pumping, and placing sand on the beach to maintain width and height. Other costs can include negative impacts on the nearshore environment. Employing these constructs, an optimal control model is specified that provides a framework for identifying the conditions under which beach replenishment enhances economic welfare and an optimal schedule for replenishment can be derived under a constant sea level and erosion rate (short term) as well as an increasing sea level and erosion rate (long term). Under some simplifying assumptions, the conceptual framework can examine the time horizon of management responses under sea level rise, identifying the timing of shift to passive management (shoreline retreat) and exploring factors that influence this potential shift. (PDF contains 4 pages)

Groundwater abstraction and plankton in the druze pool of Azraq oasis, Jordan

The Azraq oasis lies in the Jordanian desert, about 85 km east of Amman. In this brief paper the author summarises his observations from a visit to the oasis in 1991, discusses the effects of pumping groundwater from the oasis to Amman and presents results from a plankton survey.

Ecological study of the River Lambourn. Report for the period October 1970 to March 1972

A small investigation of the ecology of the river Lambourn was carried out during 1967-70. During this period it became clear that detailed and reliable information could only be obtained by a much larger investigation. The present study was planned to meet the minimum requirements. No pumping is expected during this period and, since the pumping carried out during the pilot scheme was on a small scale, it is reasonable to assume that the river is still relatively unaffected by pumping.The present investigation has two main objectives both of which depend on obtaining a detailed picture of the ecology of the river at the present time. First, it will provide basic information on the state of the river prior to the development of the pumping scheme which will be available for comparison at any later date. Secondly, it may be possible to use some of the data to predict the ecological changes which may occur if the flow of the river is altered by the pumping scheme. This report is part of a series of fives studies on the River Lambourn which were undertaken between 1970 and 1979. [PDF contains 83 pages]

Ecological study of the River Lambourn. Report for the period October 1970 to September 1973

Few detailed studies have been made on the ecology of the chalk streams. A complex community of plants and animals is present and much more information is required to achieve an understanding of the requirements and interactions of all the species. It is important that the rivers affected by this scheme should be studied and kept under continued observation so that any effects produced by the scheme can be detected. This need has been recognised by the Thames Conservancy and the Water Resources Board who jointly sponsored this investigation on one of the chalk streams involved in the scheme. The present investigation has two main objectives both of which depend on obtaining a detailed picture of the ecology of the river at the present time. First, it will provide basic information on the state of the river prior to the development of the pumping scheme which will be available for comparison at any later date. Secondly, it may be possible to use some of the data to predict the ecological changes which may occur if the flow of the river is altered by the pumping scheme. The study covers suspended solids, invertebrates, fish.This report is part of a series of fives studies on the River Lambourn which were undertaken between 1970 and 1979. [PDF contains 24 pages]

Ecological study of chalk streams. Lambourn project. Interim report October 1977 to April 1979

Few detailed studies have been made on the ecology of the chalk streams. A complex community of plants and animals is present and much more information is required to achieve an understanding of the requirements and interactions of all the species. It is important that the rivers affected by this scheme should be studied and kept under continued observation so that any effects produced by the scheme can be detected. The report gives a synopsis of work carried out between 1971 and 1979 focusing on the present phase 1978-1979. It assumes some familiarity with the investigations carried out on the River Lambourn during the preceding years. The aims of the present phase of the project may be divided into two broad aspects. The first involves collecting further information in the field and includes three objectives: a continuation of studies on the Lambourn sites at Bagnor; comparative studies on other chalk streams; and a comparative study on a limestone stream. The second involves detailed analyses of data previously collected to document the recovery of the Lambourn from operational pumping and to attempt to develop simple conceptual and predictive models applicable over a wide range of physical and geographical variables. (PDF contains 43 pages)

Ecological study of the River Lambourn. Report for the period October 1973 to September 1977

The investigations described in this report were carried out to fulfill three distinct but interrelated objectives. In 1973 the Thames Conservancy were making plans for a second stage of their groundwater scheme which would take water from the chalk aquifers in the valley of the Kennet and they wanted basic information on the ecological state of this river and its upper tributaries. Little appeared to be known about limestone streams and a preliminary study of one of the streams in this area was desirable as a basis for planning more detailed studies if these were needed later. At a progress meeting held in March 1976 the problems and opportunities presented by the developing drought conditions were considered. It was concluded that the ecological effects of the exceptionally low natural flows should be studied and that it would be important to assess the ecological impact of the groundwater scheme if it was brought into operation that year. This could only be done on the Lambourn and the Winterbourne and it was decided that considerable effort should be diverted there for this purpose and that the field observations should be extended to cover any recovery period after the end of the drought. To make this possible it was agreed that the studies of invertebrates and detritus on the Kennet should be reduced considerably and that the proposed study of the limestone stream should be abandoned. The revised objectives were as follows: A detailed ecological study of several sites on the Kennet and its tributaries above Kintbury, extending over at least two years and involving observations on wate r weeds , invertebrates, fish, detritus and the trophic relationships within the river community. Quantitativ e and qualitative sampling of water weeds and invertebrates during one year at a number of sites on several chalk streams to determine whether the patterns and relationships found in the Lambourn are also found at the other sites. Observations on the Lambourn at Bagnor were to continue for most of the period to look for long-term fluctuations and to enable these sites to act as controls with which the other sites could be compared. Further detailed studies on the Lambourn and the Winterbourne to assess the impact of low flows, trial pumping and the operation of the groundwater scheme.