Improved APEX Model Simulation of Buffer Water Quality Benefits at Field Scale

Abstract. Watershed models offer cost-effective means to quantify the environmental benefits of conservation practices. This study evaluated the ability of the Agricultural Policy/Environmental eXtender (APEX) model to simulate the effectiveness of upland buffers for reducing event runoff, sediment, and total phosphorus (TP) loadings. The study used 16 years of monitoring data (1993-2008) from three field-scale row crop watersheds. Two watersheds had buffers installed in the fall of 1997, one with upland agroforestry buffers (grass plus trees) and the second with upland grass buffers; the third watershed was maintained as a control. Objectives were to (1) determine the effect of upland buffers on APEX parameters, (2) evaluate the ability of APEX to estimate upland buffer effectiveness, and (3) evaluate the impact of alternative buffer placement options on water quality outcomes. After modification of the APEX code to improve simulation of infiltration in the buffers, we successfully calibrated APEX for no-buffer and upland buffer conditions for event runoff and TP. However, calibrated parameters from the no-buffer model simulated buffer conditions poorly and resulted in an overestimation of buffer effectiveness. Buffer effectiveness estimated with upland buffer parameters was similar to that obtained from measured data. Scenario analysis indicated that a combination of backslope and footslope agroforestry buffers was more effective than contour placement for reducing average annual edge-of-field runoff and total P losses. These results highlight the complexity of using APEX to assess upland buffers as well as potential problems when using APEX to quantify the benefits of conservation practices not included in the calibration dataset. Keywords: Agroforestry buffers, Buffer placement, Modeling, Phosphorus, Practice effectiveness, Watershed discretization.

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Exploring the Benefits of Early Contractor Involvement (ECI) and the Mechanism for Automated 5D BIM Quantification Process in Offsite Modular Construction

Modular and Offsite Construction (MOC) Summit Proceedings ◽

10.29173/mocs6 ◽

2016 ◽

Author(s):

Tochukwu Moses ◽

David Heesom ◽

David Oloke ◽

Martin Crouch

Keyword(s):

Effective Means ◽

Cost Effective ◽

Modular Construction ◽

Automated Quantification ◽

Building Information ◽

Project Risks ◽

Value Add ◽

The Uk ◽

The Impact ◽

Level 2

The UK Construction Industry through its Government Construction Strategy has recently been mandated to implement Level 2 Building Information Modelling (BIM) on public sector projects. This move, along with other initiatives is key to driving a requirement for 25% cost reduction (establishing the most cost-effective means) on. Other key deliverables within the strategy include reduction in overall project time, early contractor involvement, improved sustainability and enhanced product quality. Collaboration and integrated project delivery is central to the level 2 implementation strategy yet the key protocols or standards relative to cost within BIM processes is not well defined. As offsite construction becomes more prolific within the UK construction sector, this construction approach coupled with BIM, particularly 5D automated quantification process, and early contractor involvement provides significant opportunities for the sector to meet government targets. Early contractor involvement is supported by both the industry and the successive Governments as a credible means to avoid and manage project risks, encourage innovation and value add, making cost and project time predictable, and improving outcomes. The contractor is seen as an expert in construction and could be counter intuitive to exclude such valuable expertise from the pre-construction phase especially with the BIM intent of äóÖbuild it twiceäó», once virtually and once physically. In particular when offsite construction is used, the contractoräó»s construction expertise should be leveraged for the virtual build in BIM-designed projects to ensure a fully streamlined process. Building in a layer of automated costing through 5D BIM will bring about a more robust method of quantification and can help to deliver the 25% reduction in overall cost of a project. Using a literature review and a case study, this paper will look into the benefits of Early Contractor Involvement (ECI) and the impact of 5D BIM on the offsite construction process.

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Use of permeable, reservoir pavement constructions for stormwater treatment and storage for re-use

Water Science & Technology ◽

10.2166/wst.1999.0233 ◽

1999 ◽

Vol 39 (5) ◽

pp. 145-151 ◽

Cited By ~ 10

Author(s):

C. J. Pratt

Keyword(s):

Water Quality ◽

Urban Areas ◽

Water Environment ◽

Cost Savings ◽

Environmental Benefits ◽

Stormwater Treatment ◽

Residential Areas ◽

Materials Used ◽

The Uk ◽

The Impact

Permeable surfaces for roads and footpaths have been used as a means of disposal of stormwater in developed urban areas. Such surfaces provide an alternative to impermeable concrete or tarmacadam surfaces which would otherwise produce rapid stormwater runoff, leading to possible flooding and degeneration of receiving water quality through the uncontrolled discharge of polluted urban waters. A further advantage may be obtained from such constructions by undersealing them so as to retain stormwater for re-use for non-potable uses. The potential for general introduction of this type of storage and re-use system in residential areas is discussed and possible alternative designs for the drainage infrastructure proposed. To have widespread impact such a strategy must deliver cost savings as well as reduce the impact on the water environment of anticipated water usage demands. The source of such cost savings and the general environmental benefits of such systems will be presented. The materials used in such a sealed construction and the beneficial changes to the stored water quality are outlined. Recent work has also shown that where the pavement is used for car parking any oils dropped on the surface and washed into the structure by the stormwater may also be degraded. Details will be given of a site in the UK where the above construction is to be used to provide stormwater storage for re-use in flushing toilets at a Youth Hostel.

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Protecting soil and water quality: the impact of conservation practices

International Journal of Environmental Studies ◽

10.1080/00207239908711254 ◽

1999 ◽

Vol 57 (1) ◽

pp. 33-51 ◽

Cited By ~ 1

Author(s):

Noel S. Uri

Keyword(s):

Water Quality ◽

Conservation Practices ◽

The Impact ◽

Soil And Water

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Impact of network sectorisation on water quality management

Journal of Hydroinformatics ◽

10.2166/hydro.2017.072 ◽

2017 ◽

Vol 20 (2) ◽

pp. 424-439 ◽

Cited By ~ 2

Author(s):

Hooman Armand ◽

Ivan Stoianov ◽

Nigel Graham

Keyword(s):

Water Quality ◽

Large Scale ◽

Water Quality Management ◽

Cost Effective ◽

Pressure Control ◽

Supply Networks ◽

Potential Impact ◽

And Control ◽

The Impact ◽

Hydraulic Variables

Abstract The sectorisation of water supply networks (WSNs) includes the permanent closure of valves in order to achieve a cost-effective leakage management and simplify pressure control. The impact of networks sectorisation, also known as district metered areas (DMAs), on water quality and discolouration has not been extensively studied and it remains unknown. In addition, hydraulic variables used in the literature for assessing the likelihood of potential discolouration are limited and inconclusive. This paper investigates a methodology to evaluate the impact of networks sectorisation (DMAs) on water quality and the likelihood of discolouration incidents. The methodology utilises a set of surrogate hydraulic variables and an analysis of the hydraulic condition in pipes with historic discolouration complaints. The proposed methodology has been applied to a large-scale WSN, with and without sectors, in order to assess the potential impact of DMAs on water quality. The results demonstrate that the sectorisation of WSN (DMAs) could compromise the overall water quality and increase the likelihood of discolouration incidents. The results of this study and the proposed surrogate hydraulic variables facilitate the formulation of optimisation problems for the re-design and control of WSNs with sectorised topologies.

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A Simple Method to Map Groundwater Depth and Water Quality for Leogane, Haiti and Elsewhere

International Journal for Service Learning in Engineering Humanitarian Engineering and Social Entrepreneurship ◽

10.24908/ijsle.v16i1.14330 ◽

2021 ◽

Vol 16 (1) ◽

pp. 1-19

Author(s):

Michael Edward Kalinski ◽

Nicholas Duda ◽

Herby Lissade ◽

Harry Donaghy

Keyword(s):

Water Quality ◽

Water Table ◽

Cost Effective ◽

Groundwater Depth ◽

Simple Method ◽

Deep Aquifers ◽

Water Wells ◽

Effective Manner ◽

System 2 ◽

The Impact

In the aftermath of the January 2010 Haiti Earthquake, the streets of downtown Leogane were paved to mitigate waterborne disease using humanitarian relief funds. After paving, many of the shallow water wells in Leogane dried up. It was believed that the new pavement disrupted groundwater recharge and negatively impacted the wells. Therefore, a project was performed to assess groundwater conditions in a cost-effective manner using a rapid, inexpensive, non-intrusive geophysical approach. The scope of the project included 1) surveying the new pavement system, 2) surveying water wells in Leogane, 3) testing the well water for coliforms, 4) performing geophysical DC resistivity testing to map groundwater depth and 5) developing a groundwater map to assess the impact of the pavement on the water table. As a result of this project, it could not be concluded that the new pavement was a factor in the groundwater fluctuations observed in the water wells in Leogane. It is more likely that some of the drop in the water table was due to the earthquake itself and some of it was caused by seasonal fluctuations in the water table. It was also observed that all the water wells that extract water from shallow (less than 6 m deep) aquifers in Leogane contain coliforms due to their proximity to household latrines, although a second deeper aquifer was identified and found to be coliform-free. With respect to broader impact, this methodology represents a relatively simple approach to mapping groundwater and assessing water quality that can be easily applied to other communities in the developing world to guide their efforts to develop and manage groundwater.

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Assessing the Impact of Site-Specific BMPs Using a Spatially Explicit, Field-Scale SWAT Model with Edge-of-Field and Tile Hydrology and Water-Quality Data in the Eagle Creek Watershed, Ohio

Water ◽

10.3390/w10101299 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1299 ◽

Cited By ~ 8

Author(s):

Katherine Merriman ◽

Prasad Daggupati ◽

Raghavan Srinivasan ◽

Chad Toussant ◽

Amy Russell ◽

...

Keyword(s):

Water Quality ◽

Cover Crops ◽

Best Management Practices ◽

Swat Model ◽

Monitoring Data ◽

Quality Data ◽

Field Scale ◽

Water Quality Data ◽

Creek Watershed ◽

The Impact

The Eagle Creek watershed, a small subbasin (125 km2) within the Maumee River Basin, Ohio, was selected as a part of the Great Lakes Restoration Initiative (GLRI) “Priority Watersheds” program to evaluate the effectiveness of agricultural Best Management Practices (BMPs) funded through GLRI at the field and watershed scales. The location and quantity of BMPs were obtained from the U.S. Department of Agriculture-Natural Resources Conservation Service National Conservation Planning (NCP) database. A Soil and Water Assessment Tool (SWAT) model was built and calibrated for this predominantly agricultural Eagle Creek watershed, incorporating NCP BMPs and monitoring data at the watershed outlet, an edge-of-field (EOF), and tile monitoring sites. Input air temperature modifications were required to induce simulated tile flow to match monitoring data. Calibration heavily incorporated tile monitoring data to correctly proportion surface and subsurface flow, but calibration statistics were unsatisfactory at the EOF and tile monitoring sites. At the watershed outlet, satisfactory to very good calibration statistics were achieved over a 2-year calibration period, and satisfactory statistics were found in the 2-year validation period. SWAT fixes parameters controlling nutrients primarily at the watershed level; a refinement of these parameters at a smaller-scale could improve field-level calibration. Field-scale modeling results indicate that filter strips (FS) are the most effective single BMPs at reducing dissolved reactive phosphorus, and FS typically decreased sediment and nutrient yields when added to any other BMP or BMP combination. Cover crops were the most effective single, in-field practice by reducing nutrient loads over winter months. Watershed-scale results indicate BMPs can reduce sediment and nutrients, but reductions due to NCP BMPs in the Eagle Creek watershed for all water-quality constituents were less than 10%. Hypothetical scenarios simulated with increased BMP acreages indicate larger investments of the appropriate BMP or BMP combination can decrease watershed level loads.

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The impact of forestry as a land use on water quality outcomes: An integrated analysis

Forest Policy and Economics ◽

10.1016/j.forpol.2020.102185 ◽

2020 ◽

Vol 116 ◽

pp. 102185

Author(s):

Colm Duffy ◽

Cathal O'Donoghue ◽

Mary Ryan ◽

Kevin Kilcline ◽

Vincent Upton ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Integrated Analysis ◽

Quality Outcomes ◽

The Impact

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Impact of artificial monolayer application on stored water quality at the air–water interface

Water Science & Technology ◽

10.2166/wst.2015.337 ◽

2015 ◽

Vol 72 (7) ◽

pp. 1250-1256 ◽

Cited By ~ 1

Author(s):

P. Pittaway ◽

V. Martínez-Alvarez ◽

N. Hancock ◽

B. Gallego-Elvira

Keyword(s):

Water Quality ◽

Oxygen Demand ◽

Cost Effective ◽

Subsurface Water ◽

Water Tank ◽

Water Interface ◽

Field Investigations ◽

Air Water Interface ◽

Large Water ◽

The Impact

Evaporation mitigation has the potential to significantly improve water use efficiency, with repeat applications of artificial monolayer formulations the most cost-effective strategy for large water storages. Field investigations of the impact of artificial monolayers on water quality have been limited by wind and wave turbulence, and beaching. Two suspended covers differing in permeability to wind and light were used to attenuate wind turbulence, to favour the maintenance of a condensed monolayer at the air/water interface of a 10 m diameter tank. An octadecanol formulation was applied twice-weekly to one of two covered tanks, while a third clean water tank remained uncovered for the 14-week duration of the trial. Microlayer and subsurface water samples were extracted once a week to distinguish impacts associated with the installation of covers, from the impact of prolonged monolayer application. The monolayer was selectively toxic to some phytoplankton, but the toxicity of hydrocarbons leaching from a replacement liner had a greater impact. Monolayer application did not increase water temperature, humified dissolved organic matter, or the biochemical oxygen demand, and did not reduce dissolved oxygen. The impact of an octadecanol monolayer on water quality and the microlayer may not be as detrimental as previously considered.

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A retrospective and lessons learned from Natural Resources Canada’s Forest 2020 afforestation initiative

The Forestry Chronicle ◽

10.5558/tfc86339-3 ◽

2010 ◽

Vol 86 (3) ◽

pp. 339-347 ◽

Cited By ~ 10

Author(s):

S W.J. Dominy ◽

R. Gilsenan ◽

D W McKenney ◽

D J Allen ◽

T. Hatton ◽

...

Keyword(s):

Climate Change ◽

Global Climate ◽

Effective Means ◽

Hybrid Poplar ◽

Cost Effective ◽

Lessons Learned ◽

Environmental Benefits ◽

Fast Growing ◽

The Government ◽

Government Of Canada

Canada is seeking cost-effective means to mitigate anthropogenic greenhouse gas emissions, particularly CO2, that have been linked to global climate change. In 2003 the Government of Canada launched the Forest 2020 Plantation Development and Assessment Initiative to assess the potential for fast-growing woody crops to sequester carbon from the atmosphere. Across the country 6000 ha of plantations were established and monitored on nonforested lands (afforestation) using a variety of methods. Economic analyses assessed the investment attractiveness of this mitigation measure for a range of species and suitable lands, taking into account such factors as growth rates, agricultural opportunity costs and a range of possible carbon values. Analyses illustrated that at current trading prices for carbon and for much of the available lands and expanding markets for forest bioproducts, expected rates of return on investment for afforestation were relatively low. However, higher future carbon prices, combined with monetary values for environmental benefits, could dramatically change the economics of afforestation in the future. Key words: afforestation, carbon sequestration, forest carbon offset project, climate change mitigation, policy analysis, risk analysis, forest investment analysis, hybrids, hybrid poplar, fast-growing trees

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Productivity Benefits of Preventing Type 2 Diabetes in Australia: A 10-Year Analysis

10.2337/figshare.13315445 ◽

2021 ◽

Author(s):

Kirthi Menon ◽

Barbora de Courten ◽

Danny Liew ◽

Zanfina Ademi ◽

Alice J Owen ◽

...

Keyword(s):

Type 2 Diabetes ◽

Model Simulation ◽

Cost Effective ◽

Full Time ◽

Prevention Strategies ◽

Potential Productivity ◽

Effective Prevention ◽

Life Years ◽

The Impact

Objective: Diabetes imposes a heavy burden on both health and productivity. In this study, we sought to estimate the potential productivity gains associated with the prevention of type 2 diabetes over the next ten years in Australia. Methods: Dynamic life table models were constructed to estimate years of life lived and productivity-adjusted life years (PALYs) lived by Australians aged 20 to 69 years over the period from 2020 to 2029. The models distinguished people with and without type 2 diabetes. PALYs were ascribed a financial value equivalent to gross domestic product (GDP) per full time worker in Australia (approximately AUD $200,000). The model simulation was first undertaken assuming currently-expected trends in the incidence of type 2 diabetes, and then repeated assuming hypothetically that the incidence was reduced. The difference between the modelled outputs reflected the impact of new cases of type 2 diabetes on productivity, as well as the potential benefits of prevention. An annual 5% discount rate was applied to all outcomes. Results: Over the next decade, 140 million years of life and 87 million PALYs will be lived by Australians of working age, contributing AUD$18.0 trillion to the country’s GDP. A 10% reduction in the incidence of type 2 diabetes would result in a gain of 2,510 PALYs and AUD$532 million in GDP. Conclusion: This study illustrates the health and economic impact of type 2 diabetes and the gains that could be potentially achieved from the implementation of effective prevention strategies. However, cost-effective evaluation of these prevention strategies are needed.

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