River Derwent Research Articles

Modelling the hydraulic relationship between the River Derwent and the Corallian Limestone aquifer

Abstract The River Derwent in North Yorkshire has been identified by the Environment Agency as a river with a high priority for flow alleviation due to low flows during summer months. The river flows across the Corallian Limestone aquifer and loses flow to this aquifer, via a set of solution hollows in the stream bed. This loss in flow has been gauged, as of the order of 15 to 35 Ml/day, and in dry years the entire river flow can be lost to the aquifer. Groundwater abstraction from the Corallian Limestone aquifer varies seasonally, and is currently between 25 and 35 Ml/day, with the higher rates of pumping occurring during the summer months. One of the main groundwater abstractions is for public water supply, and this source is located about 1.5 km from the river. Abstraction from this source is largely sustained by the leakage from the river. The Corallian Limestone aquifer and its hydraulic relationship with the River Derwent has been represented using the USGS modelling package MODFLOW, to improve the understanding of the flow regime and to provide a tool to assist in the evaluation of different water resource management options. This model has provided a good representation of the aquifer system, and in particular has shown that leakage from the River Derwent is a key factor in controlling the groundwater regime and in maintaining a water balance for the aquifer. The model has been used to examine different management options for the aquifer system, including the influence of reducing the volume of water available to leak through the river bed on the groundwater abstraction sources. This paper will describe how the model has been applied to this aquifer system, the benefits obtained and the problems encountered.

On-line monitoring of micropollutants in the River Trent (UK) with respect to drinking water abstraction

Severn Trent Water (STW) have been investigating the potential of using the River Trent as a drinking water supply resource. Supply and demand assessment during recent semi-drought conditions in the United Kingdom over the last few years indicates that there is a need to utilise Trent water to safeguard supplies for the East Midlands area of England when stocks derived from the River Derwent catchment are limited. The River Trent contains the treated sewage effluent from four million people plus industry in the Midlands and along with diffuse drainage sources means that the river quality can be highly variable. In conjunction with various treatment studies on River Trent water, the pollution risks and water quality variations have been examined. The results have been used to develop an on-line monitoring station to give effective river intake protection in line with the risks found. This monitoring includes continuous low level detection (to less than 1μg/l) of multiple pesticide groups including acid herbicides, acheived by a unique development of solid phase extraction and liquid chromatography techniques.

Load estimation methodologies for British rivers and their relevance to the LOIS RACS(R) programme

Data collected from rivers within the LOIS study area have been analysed to test the reliability of commonly-used interpolation and extrapolation methods for estimating loads from the concentration and flow records that are typically available for rivers in Eastern England. Detailed time series of suspended sediment concentration and discharge, which were collected by means of turbidity monitoring and ultrasonic flow gauging on the River Wharfe at Tadcaster over a 6-month period, have been used to compute a reference load. These data were then artificially decimated to evaluate different procedures for calculating suspended sediment loads. None of the methods investigated produced very reliable load estimates when weekly suspended sediment concentration data were used, and replicate estimates ranged from 24.4 to 550.1% of the reference load. Extrapolation by means of a simple rating relationship was found to produce estimates of suspended sediment load with the highest level of accuracy and precision, but loads calculated by this procedure still varied from −57.2% to +29.1% of the true value at the 95% level of confidence. Reduction in sampling frequency from weekly to fortnightly or monthly intervals generally caused a greater underestimation and increased imprecision in the suspended sediment load estimates. The effect of applying different calculation procedures to estimate chemical fluxes was evaluated using information from the Harmonized Monitoring database for the River Derwent at Church Wilne. For 20 out of the 36 determinands investigated, the difference between the minimum and maximum load estimate, expressed as a percentage of the minimum value, exceeded 50%, and for five determinands, including arsenic in both dissolved and particulate form, the difference was 100% or more. The results of this preliminary analysis suggest that considerable caution should be exercised in calculating river fluxes to the LOIS study coastline, and underscore the need for new and improved procedures to be developed.

Influence of river flow on rod catch of Atlantic salmon, Salmo salar L., from the lower River Derwent, north‐west England

Abstract Twenty‐seven years of daily salmon, Salmo salar L., rod catch and flow data from the River Derwent were analysed. Daily catch was standardized for each month between June and October and the mean value determined for each 2‐cumec flow band. In June and July the mean standardized catch remained relatively low and stable for flows up to approximately 9 cumecs. Thereafter it increased steadily with increasing flow, reaching a peak at 21 cumecs and 41 cumecs for each month respectively. A linear model accounted for the greatest proportion of the variability in August and September with mean standardized catch increasing steadily up to a maximum value of 43 and 39 cumecs respectively. However, in October, a quadratic model was more appropriate, with mean standardized catch decreasing as flow increased up to 9 cumecs and thereafter increasing steadily with flow, reaching a maximum value at 21 cumecs. The pattern of the relationship at higher flows was not clear because of the paucity of data. These findings are discussed in relation to the management of the water resource for the maintenance of the fishery.

A between-river comparison of extracellular-enzyme activity

River-water extracellular-enzyme activity in the lowland Rivers Ouse and Derwent, northeast England, had much in common. In both rivers, the mean enzyme activities over 15 months differed in the following order: leucine aminopeptidase > phosphatase > β-D-glucosidase > β-D-galactosi-idase and β-D-xylosidase. None of the five enzymes assayed had significant between-river difference in activity, and there was significant between-river correlation of β-D-glucosidase, phosphatase, and leucine-aminopeptidase activity. The common enzyme regimes were probably more due to between-river similarity of planktonic microbiota than to similar physico-chemical conditions. The potential for glucose uptake by bacterioplankton closely followed β-D-glucosidase activity in magnitude and periodicity. The potential for leucine uptake, however, was much less than leucine-aminopeptidase activity; hence rate of leucine release probably did not limit leucine uptake. There was an appreciable and highly variable proportion of free (<0.2 μm) enzyme activity in river water; ranges were β-D-glucosidase 10-30%, phosphatase 53% to apparently 104%, and leucine aminopeptidase 22-98%. These free enzymes did not necessarily originate from planktonic microbiota and may explain the fairly loose coupling between whole-water enzyme activity and microbial variables. Marked downstream increase in enzyme activity, along about 104 km of the River Derwent, was found on only one of three sampling days; hence the single site used for regular sampling was reasonably representative of most of the river.

Lombe's Mill: An Exercise in Reconstruction

The author has examined documentary sources concerning the pioneering Lombe's Silk Mill on the River Derwent in Derby. He has combined evidence from both Italian and British sources with the physical remains and provided a reconstruction of the mill and its machinery layout. Its importance as a precursor of factory production in Britain is discussed.

The Cotton Mills of the Derbyshire Derwent and its Tributaries

Recent surveys of textile mills in Yorkshire, Greater Manchester and East Cheshire have laid the groundwork for future study in their respective areas. All three have necessarily referred back to precedents set in eighteenth century Derbyshire, where water power was first successfully applied to the manufacture of both silk and cotton. Derbyshire retains an important group of early cotton mills, most of them distributed along the River Derwent and its tributaries. Recent measured surveys of five of the most significant early mills and of a number of related sites by RCHME's Threatened Buildings Sections, supplemented by photographic coverage of further sites over many years, have provided a core of information on which the present article is largely based. The article concentrates on the surviving physical remains of the cotton industry, but draws also on documentary and other evidence for vanished structures.

Lombe's Mill: An Exercise in Reconstruction

AbstractThe author has examined documentary sources concerning the pioneering Lombe's Silk Mill on the River Derwent in Derby. He has combined evidence from both Italian and British sources with the physical remains and provided a reconstruction of the mill and its machinery layout. Its importance as a precursor of factory production in Britain is discussed.

The significance of the floodplain to the cycling of metals in the river Derwent Catchment, U.K.

This study investigates the cycling of heavy metals in a contaminated river catchment, and focuses on the important role of floodplains in the storage of fine suspended sediment. This sediment may be reworked by the contemporary river channel and the metals released could cause secondary pollution of the river. Sediment cores were collected across an extensive reach of the floodplain of the River Derwent, U.K., and sectioned at 5 cm increments to about 60 cm. Analyses of the metal content of the sediments showed a uniform addition of metals to the floodplain surface over time, although spatially there were positions on the floodplain with high concentrations of lead, zinc and cadmium. The contemporary sediments were distinguished by the presence of 137Cs, and they contained similar metal concentrations to sediments deposited during the period of active mining within the catchment. By combining information on rates of sedimentation derived from the analysis of 137Cs with average metal concentrations, the contemporary annual supply of metals to the 0.20 km 2 study reach was estimated as 360 kg of lead, 100 kg of zinc, 10 kg of copper and 2 kg of cadmium each year. These may also be expressed as loadings of metal to the floodplain surface of 1800 mg Pb, 500 mg Zn, 50 mg Cu and 10 mg Cd m −2 year −1, of which 266 mg Pb, 36 mg Zn, 5.2 mg Cu and 0.1 mg Cd m −2 year −1 was easily exchangeable and could be ‘bioavailable’.

The source, composition and flux of polycyclic aromatic hydrocarbons in sediments of the river Derwent, Derbyshire, U.K.

Freshwater surface sediments from 11 sites on the river Derwent (Derbyshire, UK) were sampled monthly during the period of June 1987 to May 1988. Samples were extracted and separated and the Polycyclic Aromatic Hydrocarbon (PAH) extract was analyzed using High Performance Liquid chromatography with a fluorescence detector. Identity of the peaks was confirmed by co-injection and Gas Chromatograph — Mass Spectrometry (GC-MS). Changes in total levels of nine parent PAH compounds were compared with rainfall data obtained for the study area. The time lag between PAH incorporation into sediments and preceding storm events varied between a minimum of 4 and a maximum of 30 days. All sites were found to be affected by diffuse PAH pollution. At certain sites and at times of heavy rainfall this contamination is overlayed by a greater input of PAH to the sediment from point sources. Road runoff was identified as a major diffuse source underlying atmospheric and point sources at particular sites. Small industrial areas had a greater influence on sediment PAH levels than the larger commercial or residential areas. Pyrene and fluoranthene were the dominant parent compounds and this is explained in terms of their availability and relative solubility.

Low-head hydroelectric power using pneumatic conversion

New hydroelectric power installations at low-head river sites are often an uneconomic proposition using conventional water turbines. This article deals with alternative power-conversion systems based on air as an intermediate fluid which are aimed at achieving a more economic solution to the problem. A novel water-to-air power-conversion system has been built at Borrowash on the River Derwent which utilises a flexible membrane as a self-oscillating interface between water and air to drive an air turbine and generator. Problems of this new technology are discussed and a number of improvements are proposed which should lead to a viable and economic alternative to conventional low-head hydro stations

The use of anglers’ catches to monitor fish populations in large water bodies, with particular reference to the River Derwent, Derbyshire, England

. Nearly 2000 marked coarse fish of four species were introduced into a stretch in the middle reaches of the River Derwent. Derbyshire, England in an attempt to estimate the fish population size from catch returns. It was estimated that 800 dace, 1975 roach, 1481 chub and 366 bream were present in the reach and the density of the fish population (0·35 fish m−2) was low. The validity of employing anglers as samplers in a mark-recapture exercise to estimate fish population size in large fisheries is discussed. Angler catch data were collected from angling clubs holding competitions on the Hoveringham Fishery on the lower reaches of the River Derwent over the period 1973/1974 to 1983/1984 to assess the impact of achange in management strategy on the fishery in 1979. Catch rates improved gradually until 1979/1980 when a dramatic increase occurred. This elevated catch rate, in excess of 400 g man-h−1, was maintained and, in recent years, further enhanced (>500 g man-h−1). The improvement was the result of a strong year-class of chub entering the catchable cohort and dominating anglers' catches and not the change in management policy.

A study of the suspended algae in the River Derwent, Derbyshire, U.K.

Studies of the composition and abundance of algae suspended in the water of the River Derwent, Derbyshire, were made during 1983. Samples were collected at intervals of 2–3 weeks from 6 sites on the lower reaches of the river. Variations in both composition and abundance of suspended algae occurred with variations in flow. At the uppermost sites cell densities were generally low (<500 cells ml−1) and the algae consisted mainly of dislodged benthic diatoms. The density in suspension of these algae of benthic origin increased with flow. At downstream sites a true potamoplankton developed; during the summer this consisted chiefly of centric diatoms with Chlorophyta and Cryptophyta. Even at the lowermost site, the maximum recorded density of cells (3 860 cells ml−1) and cell load (30 × 109 cells s−1) were lower in the Derwent than in some other British rivers. However, the cell density could still represent a substantial part (up to 32%) of the total particle density in the river.

The Effect of Cyprinid Introductions on Angler Success in the River Derwent, Derbyshire

The Effect of Cyprinid Introductions on Angler Success in the River Derwent, Derbyshire

River channel change: Problems of interpretation illustrated by the river derwent, north Yorkshire

AbstractSome inherent limitations of the spatial interpolation method of identifying and interpreting channel adjustment are illustrated by a study of the River Derwent in Yorkshire. Here, cross‐sections downstream from a river diversion appear to have contracted in size when compared with predictions based on upstream relationships between channel form variables and basin area. However, these sections are slightly larger than expected for their diminished discharge, suggesting that they have not fully adjusted to altered environmental conditions and are still in a transient state.

Prosecuting the prescription forger.

The River Trent, UK, is renowned for a rich palimpsest of alluvial archaeological remains buried within the Holocene sands and gravels of the valley floor. Since the late 1990's extraction of these postglacial deposits at Shardlow quarry in the middle reach of the valley, close to the confluence of the River Trent and River Derwent, has been investigated and monitored on a weekly basis by a project team including geoarchaeologists. Such monitoring of large exposures of floodplain sand and gravel and adjacent Pleistocene terrace deposits, initially by volunteer activity, but latterly, funded by the aggregate company under a formal planning agreement, has revealed significant alluvial archaeological remains including two logboats, a possible brushwood platform, several fish weirs and organic-rich palaeochannel deposits. This paper provides a summary of the wealth of this resource, but also reflects on the challenges of undertaking geoarchaeological studies in complex alluvial environments over such an extended time period. It concludes by providing advice for best practice that could be applied to other long term studies within similar environments.

Why were there no fish remains at Star Carr?

It is suggested that the apparent absence of pike at the settlement at Star Carr owes nothing to the seasonal occupation of the site, but can be accounted for by biological and biogeographical factors. Essentially, these are that there had been insufficient time for pike to have colonized beyond the lower reaches of the River Derwent, and that the Kirkham Priory to Malton gorge in its partly downcut state proved a barrier not just to the pike, but to the prey species which had to penetrate into and become established in the Derwent headwaters and the lake at Star Carr, before the pike could become established. This combination of circumstances resulted in the absence of pike in the Vale of Pickering during the occupation at c. 9000 years BP.

Quaternary Erosion in the Upper Derwent Basin and Its Bearing on the Age of Surface Features in the Southern Pennines

Approximate volumes of material removed from beneath the two planation surfaces in the upper Derwent basin are determined. Using published denudation rates from modern environments believed to be similar to those that have characterized the southern Pennine region during the late Quaternary, it is calculated that the highest planation feature was rejuvenated no more than i million years ago and possibly only a quarter of a million years ago, and that incision into the lower surface could conceivably have been initiated as recently as 75 ooo years ago. THE morphology of the headwater region of the river Derwent comprises three major components. These are the extensive, gently sloping plateaux and valley-side benches, the prominent escarpments, and the steep slopes adjacent to the incised drainage system (Figs i and 2). This surface configuration reflects to a large degree the gentle easterly dip of the Carboniferous shales and sandstones, but the major control on landform development has been the intermittently falling base-level that has successively rejuvenated the stream system. The plateau surfaces and valley-side benches are part of 'the upland plains' of the southern Pennines. Specifically, they represent portions of the Peak District Summit Surface and the Peak District Upland Surface described by Linton (1956). The former is represented in the area shown in Figure i by the plateau remnants above the escarpments (S) and the latter by the major benching that separates the incision from the escarpments (U). Linton (1956) interpreted the Summit Surface as the base-levelled surface produced by 'the cycle(s) of erosion that stripped away the chalk cover, removed some hundreds of feet of undermass, and saw the first group of adjustments... to the underlying structures'. The Peak District Upland Surface was claimed to be a post-mature surface of subaerial erosion cut in response to epeirogenic uplift. These two major surfaces were believed by Linton to represent the erosional work of most of Tertiary time. The incision into the Upland Surface was, according to Linton, initiated by further Tertiary uplift. Similar planation features claimed to be the result of Tertiary morphogenesis in the context of episodic uplift have since been described from other parts of the Pennines, as well as from many other parts of Britain (Brown, 1960; George, 1974; Green, 1974; Linton, 1964; Walsh et al., 1972), and correlations have been attempted by some of these authors. It is the purpose of this paper to question the proposed age of the Pennine 'surfaces'. This is done by constructing a cartographic representation of past land surfaces related to former, higher base-levels and by considering the required rate of rock removal in the intervening periods. 490 This content downloaded from 157.55.39.215 on Wed, 31 Aug 2016 04:34:35 UTC All use subject to http://about.jstor.org/terms )Quaternary erosion in the Pennines 491 c) 14*e ~~SHESH FFIELD cof rOA

Zinc, cadmium, copper, and manganese in species of finfish and shellfish caught in the Derwent Estuary, Tasmania

Thirty-nine marine species, including members of the Teleostorni and Elasmobranchii, were obtained from the River Derwent and analysed for four heavy metals known to be accumulated by certain species, particularly molluscs. Of the muscle tissues from edible Teleostomi and Elasmobranchii all contained levels of zinc, cadmium, and copper well below the maximum levels permitted by current Tasmanian food regulations. Manganese levels were also low. Small species differences for zinc and copper levels in muscle tissue are evident among these finfish. These are probably attributable to differences in feeding habits. Comparison of the metal levels in these species with levels reported by various overseas workers indicate no abnormal accumulation of heavy metals in muscle tissues. With some minor exceptions no relationships existed between the tissue metal levels and length of the fish. Two edible species of molluscs, the native oyster and the common mussel, contained much higher levels of the four metals. For both species levels of zinc and cadmium exceeded the levels specified by the food regulations. The data presented indicate that the ability of molluscs to accumulate certain metals, particularly zinc and cadmium, to abnormally high levels is not shared by finfish species. The fact that elevated metal concentrations in seawater are not reflected in the muscle tissues of finfish means that the monitoring of commercial fish species caught in the River Derwent would provide a much less sensitive index of pollution than would the monitoring of oysters or mussels.

Dr. A. A. Griffith, CBE, FRS

From June 1937, I had been working on advanced project design schemes with a small group located at the Rolls-Royce guest house. An ideal spot for quiet concentration, in extensive private grounds by the river Derwent and on the outskirts of the village of Duffield.Early in 1939, we were informed that Dr. A. A. Griffith would be occupying a room at the guest house. E. W. Hives (later Lord Hives) had invited Griffith to join Rolls-Royce and to work on the initiation of aero engine research, in particular the gas turbine and its applications.We were naturally interested to learn more about him but all that I could gather from my associates was that he was “tall, thin and had a hell of a brain”.