Rural sustainable drainage systems:a practical design and build guide for Scotland's farmers and landowners

Soil cultivation, manure / fertiliser applications and chemical spraying can all contribute to diffuse pollution from agricultural land. Rainfall runoff from farm roads, tracks, yards and dusty roofs are also potential sources of diffuse pollution. Whilst many changes in farming practice have dealt with these sources of pollution there still remains instances where small amounts escape from a farmyard into a nearby ditch or where sediment laden overland field flows make their way into a ditch or burn, river or natural wetland and finally the sea. This not only has cost implications for a farmer but these incidents across a catchment have a huge impact on our water environment. Rural Sustainable Drainage Systems (Rural SuDS) will reduce agricultural diffuse pollution impacts as they are physical barriers that treat rainfall runoff. They are low cost, above ground drainage structures that capture soil particles, organic matter, nutrients and pesticides before they enter our water environment. Rural SuDS for steadings prevent blockages in drains and ditches. They contribute to good environmental practice and farm assurance schemes. In fields they can be used for returning fertile soil back to farmland and will help your business become more resilient to the impacts of climate change. Trapping soils, organic matter and nutrients means that valuable assets can be reclaimed – recent studies indicate savings of £88 per hectare per year! This Design and Build guide can be used by farmers and land managers to reduce diffuse pollution

Catchment-scale vulnerability assessment of groundwater pollution from diffuse sources using the DRASTIC method : a case study

The catchment-scale groundwater vulnerability assessment that delineates zones representing different levels of groundwater susceptibility to contaminants from diffuse agricultural sources has become an important element in groundwater pollution prevention for the implementation of the EUWater Framework Directive (WFD). This paper evaluates the DRASTIC method using an ArcGIS platform for assessing groundwater vulnerability in the Upper Bann catchment, Northern Ireland. Groundwater vulnerability maps of both general pollutants and pesticides in the study area were generated by using data on the factors depth to water, net recharge, aquifer media, soil media, topography, impact of vadose zone, and hydraulic conductivity, as defined in DRASTIC. The mountain areas in the study area have “high” (in 4.5% of the study area) or “moderate” (in 25.5%) vulnerability for general pollutants due to high rainfall, net recharge and soil permeability. However, by considering the diffuse agricultural sources, the mountain areas are actually at low groundwater pollution risk. The results of overlaying the maps of land use and the groundwater vulnerability are closer to the reality. This study shows that the DRASTIC method is helpful for guiding the prevention practices of groundwater pollution at the catchment scale in the UK

Reducing the external environmental costs of pastoral farming in New Zealand: experiences from the Te Arawa lakes, Rotorua

Decades of nutrient pollution have caused water quality to decline in the nationally iconic Te Arawa (Rotorua) lakes in New Zealand. Pastoral agriculture is a major nutrient source, and therefore this degradation represents an external environmental cost to intensive farming. This cost is borne by the wider community, and a major publically funded remediation programme is now under way. This article describes the range of actions being taken to reduce nutrient loads from internal (lake bed sediments) and external (primarily diffuse) sources in the lake catchments. The high economic cost and uncertain efficacy of engineering-based actions to reduce internal nutrient loads is highlighted. Major changes to land management practices to control diffuse nutrient pollution are required throughout New Zealand if the need for costly and lengthy remediation programmes elsewhere is to be avoided. More action to educate farmers and the public about eutrophication issues, development and enforcement of environmental standards, and further consideration of the use of market-based instruments are proposed as ways to correct the current market failure

Determining The Cost Effectiveness Of Solutions To Diffuse Pollution: Developing A Model To Assess In-Field Mitigation Options for Phosphorous and Sediment Loss

The European Union Water Framework Directive requires governments to set water quality objectives based on good ecological status. This includes specific requirements to control diffuse pollution. Diffuse phosphorous (P) pollution plays a pivotal role in influencing water quality with losses of P associated with soil particles often linked to soil erosion. The Mitigation Options for Phosphorus and Sediment (MOPS) project, using three case study sites, is investigating the cost effectiveness of specific control measures in terms of mitigating sediment and P loss from combinable crops. The analysis is conducted at the farm level using a simple spreadsheet model. Further development of the model will allow the results to be extrapolated to generic regional farm typologies. Results from the initial farm level analysis suggest that some mitigation options may not be cost effective in reducing diffuse pollution, however, that other options may be very cost effective.Resource /Energy Economics and Policy,

The Impact of River Flow Restrictions on Instruments to Control noPoint Nitrate Pollution

An economic analysis of policies to control nonpoint source nitrate pollution in the presence of minimum river flow restrictions was undertaken. A non-linear bio-physical economic optimisation model of an intensively cultivated Scottish agricultural catchment was constructed. The presence of minimum river flow controls in the catchment was found to reduce nitrogen pollution. However, by themselves, river flow controls were found not to be a cost effective means to reduce diffuse pollution. River flow controls did not, for the most part, alter relative instrument ranking.

Reviewing factors affecting the effectiveness of decentralised domestic wastewater treatment systems for phosphorus and pathogen removal

Environmental pollution and risks to human health can result from diffuse sources of pollution originating from decentralised wastewater treatment systems (DWTS). In particular phosphorus pollution can lead to eutrophication and the downgrading of the quality of water bodies, for example, under the Water Framework Directive (WFD) in the EU, and pathogen pollution can result in increased risks of human exposure to pathogens and impacts on industries such as shellfish growing and tourism. The study reported in this paper reviews the effectiveness of various DWTS in removing phosphorus and pathogens from onsite systems. It was found that DWTS are typically not designed to specifically treat these pollutants and the most common type of DWTS, septic tanks, provide only basic treatment. Additional treatment such as filtration-based or wetland systems must be used to achieve desired levels of treatments. The performance of these systems is affected by site specific conditions, such as input load and sources, and climatic conditions and as such operational characteristics and treatment measures must be designed to take account of these factors

Demonstration test catchments : the role of hydrogeological conceptual modelling

Agricultural diffuse pollution, particularly from nitrate and phosphate, is a significant problem in the UK and is the focus of the national Demonstration Test Catchments (DTC) study — a UK Government initiative. The DTC programme is providing evidence for investigating how on-farm mitigation measures can reduce the impact of agricultural diffuse water pollution on ecological function. This will involve studying how such measures affect pollutant concentrations in so-called receptors, such as the streams which drain the catchments. It is therefore important to investigate how water moves from the land surface to the receptors and in particular to quantify the amounts and timescales involved in the different water flow routes. The DTC catchments are the Eden, the Avon and the Wensum and groundwater flow is a significant component of main river flow in all of the catchments, ranging in overall terms from around 50% of river flow in the Eden to 90% in the Avon. It is therefore important that robust conceptual models of the groundwater flow systems of the catchments — and in particular of the monitored sub-catchments — are developed. BGS is contributing to the creation of DTC groundwater conceptual models in all three study catchments. The BGS work is funded principally by NERC and by DEFRA

Emerging Rights and Risks in the Management of Water Quantity and Water Quality

Using transferable water permits has been identified by economists as a necessary tool to efficiently allocate water to its highest valued use. Australian governments have seized the concept and begun to provide mechanisms that separate rights to water from land ownership and allow flexibility to trade the rights. Water trading is slowly taking shape but has been challenged regarding ownership rights and technical applications. Several key studies and projects are now testing a similar process to be used to develop ownership and incentives for diffuse water pollution. This paper analyses how rights to water quantity and water quality are emerging, the policy tools being used, and current challenges for decision makers.Water property rights, pollution, permit trading, Environmental Economics and Policy, Resource /Energy Economics and Policy,

Voluntary agreements with Industries - participation incentives with industry-wide targets: a comment

This comment reexamines the problem of free-riding in pre-emptive collective environmental voluntary agreements (VA) analysed by Dawson and Segerson in the context of VAs with a global emission target and a pigouvian tax used as a threat. Completely remaining in the authors' framework, we here reconsider their results about efficiency. While they claim it provides the optimal amount of environmental quality but inefficiently, we show that there exists an optimal threat under which the equilibrium of the game is a cost-effective VA. This result gives an additional indication on the way VAs should be used to be efficient.collective voluntary agreements, pollution control, adoption costs, political processes, distributional effects, diffuse pollution, government policy