An evaluation of rainwater runoff quality from selected white roof membranes

2012 ◽  
Vol 47 (1) ◽  
pp. 66-79 ◽  
Author(s):  
Anthony Cupido ◽  
Brian Baetz ◽  
Yiping Guo ◽  
Anna Robertson
Keyword(s):  
Field Research ◽  
Green Building ◽  
Green Roofs ◽  
Institutional Setting ◽  
Modified Bitumen ◽  
Runoff Water ◽  
Rainwater Runoff ◽  
Thermoplastic Polyolefin ◽  
Runoff Quality

While there has been research on rainwater quality and quantity from green roofs and some conventional roof systems, there does not appear to be any significant study regarding the quality of rainwater harvested from selected white membrane roof systems and subsequently treated for potable use in an urban, institutional setting. A new Leadership in Energy and Environmental Design (LEED®) Canada Gold facility on the campus of McMaster University in Hamilton, Canada offered an excellent opportunity to analyze the quality of rainwater from different roof assemblies. Field research was undertaken on the evaluation of three white roof membranes: modified bitumen finish ply, polyvinyl chloride (PVC), and thermoplastic polyolefin (TPO); and their effects on the runoff water quality were studied. An analysis of the quality of runoff was performed from each of these three membranes and compared with Ontario provincial drinking water standards. This paper provides the results of runoff quality testing on these membranes and their suitability for future institutional green building applications.

scholarly journals Hydrological Performance and Runoff Water Quality of Experimental Green Roofs

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1185 ◽  
Author(s):  
Grzegorz Pęczkowski ◽  
Tomasz Kowalczyk ◽  
Katarzyna Szawernoga ◽  
Wojciech Orzepowski ◽  
Romuald Żmuda ◽  
...  
Keyword(s):  
Total Nitrogen ◽  
Green Roofs ◽  
Control Surface ◽  
Substrate Thickness ◽  
Storm Events ◽  
Runoff Water ◽  
Relative Retention ◽  
Runoff Reduction ◽  
Relative Retention Index

Within the scope of the conducted experiment the authors analysed the efficiency of runoff reduction by the system of extensive type green roofs. The observations were based on storm events in the area of Lower Silesia at the Agro and Hydrometeorology Station Wrocław-Swojec. The authors analysed the thickness of plant substrate, and also estimated the quality of runoff waters under the conditions of periodic atmospheric deposition. Also considered were such indicators as electrolytic conductivity, N, NO3−, NO2−, NH4+, P, PO43−. The experiment included roof substrates designed in two variants, with known hydraulic and physical properties of the soil material. The analysis was performed for models with vegetation layer based on pumice and zelolite, covered with five plant species from the sedum family. The modelling of the hydraulic properties was conducted with variably saturated medium, using the Hydrus 1D software. The performance of systems with primary layer thickness of 11 cm and 9, 8, 7, 6 and 5 cm was estimated. The designed models reduced the average peak flows to 89%, and in addition they caused a delay in the initiation of the runoff which was dependent on the intensity and distribution of rainfalls in time, and on the initial moisture of the profiles. Simulations, performed for variable substrate thickness, permit the conclusion that in the case of thin-layer profiles (5 cm), the relative retention index was decidedly lower and amounted to 35.9% for the substrate with zeolite (originally 60.6%) and 41% for the substrate with pumice (originally 65.7%). In the case of total nitrogen and phosphates, statistical analysis revealed significant differences (p < 0.05) in relation to specific concentrations in the rainwater and in the control surface. The total nitrogen in the runoff from the green roof was nearly twice as high as that in the rainwater and amounted to, on average, 8.3 mg L−1.

Research on the characteristics of the water quality of rainwater runoff from green roofs

2014 ◽  
Vol 70 (7) ◽  
pp. 1205-1210 ◽  
Author(s):  
Kena Gong ◽  
Qing Wu ◽  
Sen Peng ◽  
Xinhua Zhao ◽  
Xiaochen Wang
Keyword(s):  
Water Quality ◽  
Retention Rate ◽  
Oxygen Demand ◽  
Green Roofs ◽  
Water Runoff ◽  
Runoff Water ◽  
Retention Capacity ◽  
Storm Water Runoff ◽  
Quality Retention ◽  
Rainwater Runoff

This paper investigates the water quality characteristics of rainwater runoff from dual-substrate-layer green roofs in Tianjin, China. The data were collected from four different assemblies and three types of simulated rains. The storm-water runoff quality was monitored from early June through late October 2012 and from July through late November 2013. The results revealed that the runoff water quality would be improved to some extent with the ageing of green roofs and that the quality retention rate better reflected the pollutant retention capacity of the green roof than the pollutant concentration in the runoff water. The investigation clearly demonstrated that green roofs also effectively reduced the chemical oxygen demand and turbidity value and neutralised acid rain to stabilise the pH of the runoff.

scholarly journals Impact of Green Roofs and Vertical Greenery Systems on Surface Runoff Quality

Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2609
Author(s):  
Imane Hachoumi ◽  
Bernhard Pucher ◽  
Elisabetta De Vito-Francesco ◽  
Flora Prenner ◽  
Thomas Ertl ◽  
...  
Keyword(s):  
Aquatic Environment ◽  
Urban Areas ◽  
Green Building ◽  
Urban Runoff ◽  
Green Roofs ◽  
Pollution Source ◽  
Special Focus ◽  
Stormwater Treatment ◽  
Materials Used

Green roofs (GRs) and vertical greenery systems (VGSs) can contribute certain pollutants to stormwater runoff, affecting the quality of the receiving waters. The objective of this review paper is to discuss the potential impact of these systems on the quality of urban runoff. In the green building systems section, a series of materials used in greenery systems and their specific application are presented and environmentally relevant substances that could be leached out from these materials are identified as potential pollutants. After the identification of environmentally relevant pollutants that have already been measured in urban runoff and originate from these systems, an assessment of their pathways, fate, and impact in the aquatic environment is performed. Since GRs and VGSs are already considered to be solutions for stormwater quantity and quality management in urban areas, recommendations for mitigating their environmental impact through runoff are needed. It can be concluded that special focus should be placed on measures that target the pollution source, such as optimizing GR and VGS construction practices and materials used, as well as establishing appropriate decentralized stormwater treatment measures. Both of these approaches will help to reduce or even entirely avoid the emission of relevant pollutants into the aquatic environment.

The influence of extensive green roofs on rainwater runoff quality: a field-scale study in southwest China

2019 ◽  
Vol 27 (12) ◽  
pp. 12932-12941 ◽  
Author(s):  
Ruifen Liu ◽  
Richard L. Stanford ◽  
Yun Deng ◽  
Defu Liu ◽  
Ying Liu ◽  
...  
Keyword(s):  
Southwest China ◽  
Green Roofs ◽  
Field Scale ◽  
Rainwater Runoff ◽  
Extensive Green Roofs ◽  
Runoff Quality

EFFECT OF GREEN ROOF AGE ON RUNOFF WATER QUALITY IN PORTLAND, OREGON

2018 ◽  
Vol 13 (2) ◽  
pp. 42-54 ◽  
Author(s):  
Jarrett Okita ◽  
Cara Poor ◽  
Jessica M. Kleiss ◽  
Ted Eckmann
Keyword(s):  
Water Quality ◽  
Urban Areas ◽  
Water Retention ◽  
Green Roof ◽  
Green Roofs ◽  
Dry Season ◽  
Rain Event ◽  
Wet Season ◽  
Runoff Water

Green roofs have become a common method to increase water retention on-site in urban areas. However, the long-term water quality of runoff from green roofs is poorly understood. This study evaluated the water quality of stormwater runoff from a regular (non-vegetated) roof, a green roof installed 6 months previously, and a green roof installed 6 years ago in Portland, Oregon. Samples of runoff were taken during every rain event for 10 months, and analyzed for total phosphorus (TP), phosphate (PO3-4), total nitrogen (TN), nitrate (NO-3), ammonia (NH3), copper (Cu), and zinc (Zn). Runoff from the green roofs had higher concentrations of TP and PO3-4 and lower concentrations of Zn compared to the regular roof. Average TP concentrations from the 6-year old roof and 6-month old roof were 6.3 and 14.6 times higher, respectively, than concentrations from the regular roof, and average PO3-4 concentrations from the 6-year old roof and 6-month old roof were 13.5 and 26.6 times higher, respectively, compared to the regular roof. Runoff from the 6-month old green roof had higher concentrations of TP and PO3-4 than the 6-year old green roof during the wet season, but lower concentrations during the dry season. The 6-month old green roof installations where receiving waters are sensitive or impaired may need additional treatment methods to reduce phosphorus levels. As green roofs age, water retention decreases and phosphorus leaching increases during the dry season.

Pengembangan Minat Baca Peserta Didik : Studi Peran Kepala Sekolah

2018 ◽  
Vol 2 (2) ◽  
pp. 84
Author(s):  
Fahrurrrazi Fahrurrrazi
Keyword(s):  
Descriptive Analysis ◽  
Field Research ◽  
Learning Ability ◽  
Analysis Technique ◽  
Role Of Principal ◽  
Strategic Role ◽  
Management Functions ◽  
Reading Interest

Penelitian ini dilatarbelakangi oleh fenomena minat baca siswa dan pengaruh minat baca terhadap pertumbuhan kemampuan belajar siswa pada jenjang-jenjang pendidikan selanjutnya. Kepala sekolah sebagai lokomotif perkembangan mutu pendidikan memiliki peran strategi bagi pengumbuhan dan pengembangan minat baca peserta didik. Penelitian ini bertujuan untuk mengetahui peran kepala madrasah sebagai edukator, manajer, dan innovator dalam pengembangan minat baca peserta didik di MIT Nurul Islam Kota Semarang. Penelitian ini merupakan penelitian kualitatif lapangan, data dikumpulkan melalui observasi, wawancara, dokumentasi dan triangulasi, serta dianalisis dengan teknik analisis deskriptif. Hasil penelitian ini menunjukkan bahwa: 1) Peran kepala madrasah sebagai edukator dalam pengembangan minat baca peserta didik meliputi meliputi tiga pembinaan, yakni pembinaan mental dan moral, serta pembinaan artistik. 2) Peran kepala madrasah sebagai manajer dalam pengembangan minat baca peserta didik di MIT Nurul Islam meliputi penerapan fungsi-fungsi manajemen dengan didasarkan pada pada kerjasama dengan USAID dan UIN Walisongo Semarang. 3) Peran kepala madrasah sebagai innovator dalam pengembangan minat baca peserta didik di MIT Nurul Islam Kota Semarang meliputi inovasi strategi, pola pikir (mindset) dan struktur. Abstract This research is motivated by the phenomenon of reading interest of students and the influence of reading interest on the growth of students' learning ability in the next level of education. The principal as a locomotive of the development of the quality of education has a strategic role for the growth and development of reading interest of learners. This study aims to determine the role of principal as an educator, manager, and innovator in the development of reading interest of learners in MIT Nurul Islam Semarang City. This research is a qualitative field research, data collected through observation, interview, documentation and triangulation, and analyzed by descriptive analysis technique. The results of this study indicate that: 1) The role of principal as an educator in the development of reading interest of learners includes three activities are coaching, namely mental and moral coaching, and artistic coaching. 2) The role of principal as manager in the development of reading interest of learners at MIT Nurul Islam covers the application of management functions based on cooperation with USAID and UIN Walisongo Semarang. 3) The role of principal as innovator in the development of reading interest of learners at MIT Nurul Islam Semarang City includes innovation strategy, mindset, and structure.

scholarly journals Population-based rapid assessment of avoidable blindness survey in Sohag governorate in Egypt

BMJ Open ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. e036337
Author(s):  
Heba AlSawahli ◽  
Ian McCormick ◽  
Caleb D Mpyet ◽  
Gamal Ezzelarab ◽  
Mohammad Shalaby
Keyword(s):  
Cataract Surgery ◽  
Census Data ◽  
Rapid Assessment ◽  
Population Based ◽  
Vision Impairment ◽  
Health System Strengthening ◽  
Secondary Outcome ◽  
Institutional Setting ◽  
Financial Barriers

ObjectivesTo determine the prevalence and causes of blindness and vision impairment, and the coverage and quality of cataract surgical services, among population aged 50 years and older in Sohag governorate in Egypt.DesignA population-based cross-sectional survey using two-stage cluster random sampling following the rapid assessment of avoidable blindness methodology.SettingA community-based survey conducted by six teams of ophthalmologists, assistants and local guides. Enrolment and examination were door-to-door in selected clusters.ParticipantsUsing 2016 census data, 68 population units were randomly selected as clusters (of 60 people) with probability proportionate to population size. Anyone aged 50 years and older, residing in a non-institutional setting in a cluster for at least 6 months, was eligible to participate.Primary and secondary outcome measuresThe prevalence and causes of blindness and vision impairment. Secondary outcomes were CSC and effectiveness and participant-reported barriers to cataract surgery.ResultsOf 4078 participants enrolled, 4033 (98.9%) were examined. The age-adjusted and sex-adjusted prevalence of blindness, severe vision impairment and moderate vision impairment were 5.9% (95% CI 4.8% to 6.9%), 4.7% (95% CI 3.8% to 5.7%) and 18.9% (95% CI 16.8% to 21.0%), respectively. Cataract caused most of blindness (41.6%), followed by non-trachomatous corneal opacity (15.7%) and posterior segment diseases (14.5%). Cataract surgical coverage (CSC) for persons for visual acuity <3/60 was 86.8%, the proportion of cataract surgeries with poor visual outcome was 29.5% and effective CSC (eCSC) was 44.9%. eCSC was lower in women than men. The most frequently reported barrier to surgery was cost (51.5%).ConclusionsThe prevalence of blindness in Sohag governorate is higher than districts in other middle-income countries in the region. CSC was high; however, women suffer worse quality-corrected CSC than men. The quality of cataract surgery needs to be addressed, while health system strengthening across government and private settings could alleviate financial barriers.

scholarly journals Addressing the Water–Energy–Food Nexus through Enhanced Green Roof Performance

2021 ◽  
Vol 13 (4) ◽  
pp. 1972
Author(s):  
Jeremy Wright ◽  
Jeremy Lytle ◽  
Devon Santillo ◽  
Luzalen Marcos ◽  
Kristiina Valter Mai
Keyword(s):  
Climate Change ◽  
Performance Optimization ◽  
Urban Areas ◽  
Stormwater Management ◽  
Green Roof ◽  
Green Roofs ◽  
Management Tool ◽  
Contributing Factors ◽  
Rainwater Runoff ◽  
Rain Events

Urban densification and climate change are creating a multitude of issues for cities around the globe. Contributing factors include increased impervious surfaces that result in poor stormwater management, rising urban temperatures, poor air quality, and a lack of available green space. In the context of volatile weather, there are growing concerns regarding the effects of increased intense rainfalls and how they affect highly populated areas. Green roofs are becoming a stormwater management tool, occupying a growing area of urban roof space in many developed cities. In addition to the water-centric approach to the implementation of green roofs, these systems offer a multitude of benefits across the urban water–energy–food nexus. This paper provides insight to green roof systems available that can be utilized as tools to mitigate the effects of climate change in urbanized areas. A new array of green roof testing modules is presented along with research methods employed to address current issues related to food, energy and water performance optimization. Rainwater runoff after three rain events was observed to be reduced commensurate with the presence of a blue roof retention membrane in the testbed, the growing media depth and type, as well as the productive nature of the plants in the testbed. Preliminary observations indicate that more productive green roof systems may have increasingly positive benefits across the water–energy–food nexus in dense urban areas that are vulnerable to climate disruption.

The quality of runoff water collected from a wheat field margin in Greece

2002 ◽  
Vol 89 (1-2) ◽  
pp. 117-125 ◽  
Author(s):  
S.E. Tsiouris ◽  
A.P. Mamolos ◽  
K.L. Kalburtji ◽  
D. Alifrangis
Keyword(s):  
Runoff Water ◽  
Field Margin ◽  
Wheat Field
Sign in / Sign up

Export Citation Format

Share Document