Banca de DEFESA: VALÉRIA CARNEIRO DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : VALÉRIA CARNEIRO DOS SANTOS
DATE: 24/09/2021
TIME: 14:00
LOCAL: Sala de reunião do Google Meet: https://meet.google.com/tkz-bifz-ciw
TITLE:

Assesment of a rooftop rainwater harvesting system by continuous simulation with subdaily data

KEY WORDS:

Runoff; Rainwater harvesting; SWMM; Continuous simulation.

PAGES: 112
BIG AREA: Engenharias
AREA: Engenharia Sanitária
SUBÁREA: Saneamento Básico
SPECIALTY: Drenagem Urbana de Águas Pluviais
SUMMARY:

Sustainable urban drainage proposes alternative techniques that promotes hydrological regimes closer to their natural states. Hence, rainwater harvesting supplement water for non-potable uses and, at the same time, contributes to control storm water runoff at the source. Therefore, the aim of this study was to assess the performance of a rainwater harvesting system (RHS) in storm water runoff control and also the simulation method with daily data, commonly used in design of rainwater harvesting reservoirs. For this, 1 minute time interval rainfall and flow rate continuous series were used for SWMM 5.1 calibration. Then, a continuous series of seven years of gauged precipitation was used to simulate the whole system (roof - "first-flush" tank - main tank) for different non-potable water demand scenarios and this serie also used data with 1 minute time interval. The assessment was based in terms of water saving efficiency, rainwater waste ratio, reliability and peak and volume reduction rates. At calibration phase, the Nash-Sutcliffe coefficient values obtained at continuous simulation of RHS were high (>0.94). At the assessment of the RHS at monitoring months, from July 2018 to March 2019, the volume and peak reductions were equal to 34% and 98%, respectively, being used rainwater volume by residents equivalents to 1.2% of average total consumption on january. At simulated period, from 2014 to 2020, the reduction rates were 45% to 48% (volume) and 98% (peak) in the six simulated scenarios. The best scenario, in terms of demand, was scenario 1 where the water saving efficiency was 0.38 and the reliability was 37%. As for the simulation method, with daily interval, for a full reliability of 90%, a daily demand of 4.3 liters/day was obtained, whereas in the continuous simulation, using SWMM, the demand was 2.4 liters/day, difference of approximately 40%. For the 90% reliability scenario, the volume and peak reductions were 13% and 95%, respectively. The relevance of monitoring the "first discharge" tank and also of the continuous simulations series with appropriate resolution was observed. The "first discharge" tank captures a part of the low intensity events and the used way of continuous simulation can represent hidden aspects at more simplified methods using daily data series without evaporation data for example. At the end of this study, it was possible to conclude that although there are challenges to reconcile the uses of rainwater harvesting, the adoption of this technique can be advantageous in storm water runoff mitigation and that, from continuous simulation with SWMM as reference, the simulation method with daily data can overestimate the volumes.

BANKING MEMBERS:
Presidente - 1640249 - MARLLUS GUSTAVO FERREIRA PASSOS DAS NEVES
Interna - 1121094 - CLEUDA CUSTODIO FREIRE
Interno - 1357436 - VLADIMIR CARAMORI BORGES DE SOUZA
Externo à Instituição - ALFREDO AKIRA OHNUMA JÚNIOR - UERJ