Geological structure as a control on floodplain groundwater dynamics

Groundwater in upland floodplains has an important function in regulating river flows and controlling the coupling of hillslope runoff with rivers, with complex interaction between surface waters and groundwaters throughout floodplain width and depth. Heterogeneity is a key feature of upland floodplain hydrogeology and influences catchment water flows, but it is difficult to characterise and therefore is often simplified or overlooked. An upland floodplain and adjacent hillslope in the Eddleston catchment, southern Scotland (UK), has been studied through detailed three-dimensional geological characterisation, the monitoring of ten carefully sited piezometers, and analysis of locally collected rainfall and river data. Lateral aquifer heterogeneity produces different patterns of groundwater level fluctuation across the floodplain. Much of the aquifer is strongly hydraulically connected to the river, with rapid groundwater level rise and recession over hours. Near the floodplain edge, however, the aquifer is more strongly coupled with subsurface hillslope inflows, facilitated by highly permeable solifluction deposits in the hillslope–floodplain transition zone. Here, groundwater level rise is slower but high heads can be maintained for weeks, sometimes with artesian conditions, with important implications for drainage and infrastructure development. Vertical heterogeneity in floodplain aquifer properties, to depths of at least 12 m, can create local aquifer compartmentalisation with upward hydraulic gradients, influencing groundwater mixing and hydrogeochemical evolution. Understanding the geological processes controlling aquifer heterogeneity, which are common to formerly glaciated valleys across northern latitudes, provides key insights into the hydrogeology and wider hydrological behaviour of upland floodplains

Pragmatists versus dogmatists: Explaining the failure of power-sharing in Northern Ireland during the 1970s

This article argues that the failure of Northern Ireland’s first power-sharing executive, and subsequent attempts to restore power-sharing during the 1970s, was the result of conflicting attitudes towards devolution among Northern Ireland’s politicians. Traditional ideological divisions between nationalists and unionists were not the primary barrier to creating and sustaining cross-community institutions, as stressed in accounts of this period premised on consociational theory. Drawing extensively from archival sources, it argues that the split between the pragmatists from both communities, who were prepared to compromise their core principles and accept power-sharing devolution within a UK framework, and the dogmatists (both nationalists and unionists) who refused to contemplate any compromise to their core position, prevented a consensual political settlement emerging during the 1970s

Eddleston Water Floodplain Project : data report

This report describes work done to characterise the shallow (Quaternary) subsurface environment (geology, hydrogeology and soil hydrology) of a new environmental experimental site at Eddleston, Scottish Borders, and presents the data that were gathered during an extensive and detailed investigation of the experimental site. These data form the basis for an in depth interpretation and characterisation of the geology, hydrogeology and soil hydrology of the site, which will be presented separately. The Eddleston experimental site was set up as part of the wider Eddleston Water Project, which aims to reduce the impact of flooding in and downstream of Eddleston. A key objective of the experimental site is to improve understanding of the role of groundwater in floodplain environments and in flooding, and of how groundwater interacts with climate, rivers and soils. The following activities have been carried out and are reported here: • The geology of the site has been characterised by geological re-surveying, trial pitting, geophysical surveying, drilling, and the development of a three dimensional geological model. • The hydraulic properties of the Quaternary aquifer beneath the floodplain have been characterised by test pumping. • Soil permeability in areas of different land use across the site has been established, and areas of completely saturated soil identified. • The hydraulic properties of the shallow (<2m) deposits beneath the wetland area have been characterised by test pumping. • Equipment has been installed to enable long term monitoring of soil moisture, groundwater levels and groundwater temperature

Being Human and the Internet; Against Dichotomies

Ethics defines a distance between what is and what ought to be. This distance designates a space where we have something to do. On the other hand, dogmatism is authorized by a reality that it claims to represent and in the name of this reality, it imposes laws. (Certeau, 1986: 199

Research summary. A critical review Of urban diffuse pollution control: methodologies to identify sources, pathways and mitigation measures with multiple benefits. CRW2012/1.

The main aim of this research was to inform the development of policy to support implementation of the Water Environment and Water Services (Scotland) Act 2003 and the Flood Risk Management (Scotland) Act (2009). Surface water management in urban areas is increasingly important in policy areas concerned with flooding and pollution, in addition to these policy areas benefits can be realised in health and well-being (through green space provision or improvement), in traffic management, in operation and maintenance delivery (and cost savings) for urban areas, and in biodiversity and climate change planning. Therefore to support guidance on surface water management there is a need to: 1. Develop integrated tools that are relevant to understanding sources, pathways and mitigation of diffuse contaminants. 2. Critically assess which methods best identify sources and pathways for a given urban environment and/or readily available information. 3. Identify mitigation strategies, from source to end-of-pipe that meet the twin challenge of diffuse pollution prevention and multiple benefits in terms of cost, energy and water sustainability

Characterising groundwater-surface water connectivity in the lower Gandak catchment, a barrage regulated biodiversity hotspot in the mid-Gangetic basin

The alluvial aquifer system of the Indo-Gangetic Basin (IGB) is one of the world’s most important freshwater resources, sustaining humans and river ecosystems. Understanding groundwater recharge processes and connections to meteoric and surface water is necessary for effective water resource management for human and wider ecological requirements. Parts of the mid-Gangetic Basin, across eastern Uttar Pradesh and Bihar, are characterised by stable long-term groundwater levels, high annual rainfall, and limited historical groundwater use compared to parts of Northwest India for example. In this paper we use a combination of environmental tracers and hydrograph observations to characterise sources of recharge and groundwater-surface water interaction using a transect approach across the catchment of the River Gandak, a major barrage-regulated tributary of the River Ganga. Stable isotope results show that the dominant source of groundwater recharge, in the shallow (0–40 m bgl) Holocene and underlying Pleistocene aquifer system (>40 m bgl), is local rainfall. The shallow Holocene aquifer is also supplemented by local recharge from river and canal seepage and irrigation return flow in the upper and mid parts of the catchment. These observations are corroborated by evidence from detailed groundwater hydrographs and salinity observations, indicating localised canal, river and lake connectivity to groundwater. In the middle and lower catchment, river discharge is dominated by groundwater baseflow during the peak dry season when barrage gates are closed, which contributes to ecological flows for endangered river dolphins and gharial crocodiles. Groundwater residence time tracers indicate active modern recharge in the shallow alluvial aquifer system across the catchment. In the shallow Holocene aquifer elevated arsenic (As), iron (Fe), and manganese (Mn) exceeded WHO drinking water guidelines in a minority of sites, and uranium (U) and fluoride (F) concentrations approach but do not exceed the WHO guideline values. These observations varied across the catchment with higher As, Fe and Mn in the upper and mid catchments and higher U in the lower catchment. Groundwater salinity was typically between 500 and 1000 μS/cm, and isolated higher salinity was due to recharge from flood-plain wetlands and lakes impacted by evaporation. At present, the Gandak catchment has relatively high rainfall and low abstraction, which maintains stable groundwater levels and thus baseflow to the river in the dry season. Potential future threats to groundwater resources, and therefore river ecology due to the sensitivity to changes in baseflow in the catchment, would likely be driven by reductions in local monsoon rainfall, changes in water management practices and increased groundwater use

Laneside, Then Left a Bit? Britain's Secret Political Talks with Loyalist Paramilitaries in Northern Ireland, 1973–1976

This article examines talks that took place between British government officials and loyalist paramilitary groups in Northern Ireland at a critical moment in the most recent Troubles. In particular, this article describes talks that took place secretly at the Northern Ireland Office's ‘Laneside’ building, a secluded suburban house used by British diplomats and MI6 officers on the shores of Belfast Lough between 1971 and 1976. Drawing on both recently released archive material as well as interviews with those who worked at and visited Laneside, this article explores what went on at these talks and analyses their outcomes from three different perspectives. This article demonstrates that the most accurate perspective from which to view what occurred in these meetings is neither top-down (government led) nor bottom-up (paramilitary led), but one that looks at what went on there as part of a conversation which both sets of participants for a time found useful. For the loyalists, Laneside had a role as a venue to think about strategy (rather than negotiate ends). For the British these were conversations that were useful in furnishing their understanding of loyalism, and as a place where policies could be explained and problems better understood. Looking at what occurred at Laneside as a semi-autonomous governmental body in Northern Ireland reveals key insights into both the loyalist paramilitaries' political ideas as well as the aims of British policy in Northern Ireland. Furthermore, this middle perspective holds a mirror up to the more familiar talks then occurring between the very same British officials and the Provisional IRA

Towards understanding the Dumfries Basin aquifer, SW Scotland

The Dumfries Basin aquifer supports groundwater abstraction for public supply, agriculture and industry. Abstraction is concentrated in the western part of the basin, where falling groundwater levels and deteriorating water quality both reflect the effects of intense pumping. There are two bedrock units: a predominantly breccia–coarse sandstone sequence in the west, interfingering with a predominantly sandstone sequence in the NE and east. The basin is bounded by weakly permeable Lower Palaeozoic rocks, and is largely concealed by variable superficial deposits. Surface water flows onto the basin from the surrounding catchment via the Nith and the Lochar Water and their respective tributaries. Direct rainfall recharge occurs via superficial sands and gravels, especially in the north, and discharge is predominantly to the rivers in the central area rather than the sea. A picture is developing of two main aquifer types within the basin: the high-transmissivity western sector underlain by a fracture-flow system with younger water and active recharge and a high nitrate content, compared with the east where groundwater residence times are longer and the storage capacity is higher