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Ecodrainage System in Overcoming Floods Jump (Run Off) In Village Settlements Popoh, Wonoayu
District, Sidoarjo
Novita Lia Fitri Handayani, Adi Prawito
Civil Engineering Study Program, Faculty of Engineering & Computer Science, Narotama University Surabaya, Indonesia
[email protected], [email protected]
Abstract
Sidoarjo Regency is an area that attracts residents to migrate, resulting in the rapid development of the population. Sidoarjo Regency has an area of 714.27 km² with a total population density of 2,916 people/km².
The rapidly increasing number of residents and the development of settlements/housing and other supporting facilities are not matched by the development of the drainage system. One of the impacts is an increase in direct surface runoff and a decrease in the quantity of water that seeps into the ground, resulting in puddles/floods in the rainy season and a threat of water drought in the dry season. It is necessary to have a planning for the implementation of a drainage system where there is a change in the conventional drainage concept into an environmentally sound drainage concept (eco-drainage) so that later excess water, especially rainwater can be accommodated and controlled so that it seeps into the ground so as to reduce overflow of water to the surface which causes inundation. With the planning for the application of the concept of environmentally sound drainage (eco-drainage) it is hoped that it can reduce inundation/floods that occur in Popoh Village Residents' Settlements and can support water resource conservation efforts, one of which is by using infiltration wells.The method used in this planning uses the calculation of hydrological analysis, hydraulic analysis, and the determination of the number of infiltration wells using the calculation method of infiltration wells.The dimensions of the planned infiltration wells are typically 2 m deep, 1.4 m diameter well and 0.5 m radius with a capacity of 3,077 m/second for each well. So, it takes as many as 4 infiltration wells which are planned to be placed in the catchment area of the drainage channel where the inundation occurs.
Keywords:
Eco-drainage, Inundation, Infiltration Well
1. Introduction
In accordance with the Regulation of the Minister of Public Works of the Republic of Indonesia Number 12/PRT/M/2014 concerning the Implementation of the Urban Drainage System. Therefore, the increase in development must be carried out in a directed manner and with good coordination. In the field conditions in the Sidoarjo area itself, the environmental infrastructure for housing development still does not meet the quality and quantity requirements. Based on a literature study, the direction of the drainage system drainage in Popoh Village, Wonoayu District is directed towards the tertiary patusan towards the canal waterstat. The existing dimensions of the tertiary patusan used are 2.00 meters wide and 1.20 meters deep with the channel boundaries for buildings 2.00 meters apart. At the research location, the maximum water level that has occurred at the activity location is 0. 50m from the fixed point of the planned settlement development activity, so for land filling the area must adjust the height of the intended flood level or higher.
In residential areas, residents have a land area of ± 25,000 m².
2. Literature Review
2.1. Drainage SystemDrainage is one of the basic structures to meet the needs of the community which is the most important component in a city's infrastructure planning. Drainage aims to make a city infrastructure safe, comfortable, clean and healthy (Maria, 2012).
The uses of drainage according to Maria are:
1. Drain waterlogged areas so that there is no accumulation of water in the soil.
2. Lowering the groundwater level to an ideal level.
3. Controlling soil erosion, damage to existing roads and buildings.
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4. Controlling excessive rainwater so that unwanted flooding does not occur.
2.2. Rational Method
According to Wanielista (1990) the rational method is one of the oldest methods and was originally used only to estimate peak discharge. This can be expressed in the Rational formula as follows (Chow, 1998)
Q = 0.277 x C x I x A (1)
The constant 0.277 is the conversion factor for peak discharge to units (m³/s) (Seyhan, Soenardi, &
Sentot, 1990).
2.3. Log Person Method
Log Person Type III distribution is widely used in hydrological analysis, especially in the analysis of maximum (flood) and minimum (minimum discharge) with extreme values. The form of the Log Person Type III distribution is the result of the transformation of the Type III Person distribution by replacing the variates into logarithmic values. The probability density function equation is the cumulative form of the Log Pearson Type III distribution with the variable value X when described on a logarithmic probability paper it will be a mathematical model of a straight-line equation. The equation of the straight line is:
Y = Y- k S (2) With:
Y : The logarithmic value of X Y : Average value of Y S : Standard deviation of Y
K : Characteristics of the type III log person distribution 2.4. Infiltration wells
Descriptive analysis is an analysis which is the collection, processing, and presentation as well as Rainwater Infiltration Wells (SRAH is an infrastructure to accommodate and absorb water into the ground.
Rainwater that is accommodated and infiltrated comes from plots of land, building roofs and soil surfaces that are impregnated for maintain the balance of the water management system in the residential environment, only to accommodate SRAH rainwater, not waste water.
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3. Research Methodology
3.1. Flow diagram
Figure 1 Research methodology
31 3.2. Research sites
The research location is in Popoh Village, Wonoayu District, Sidoarjo Regency.
Figure 2 Administration Map
4. Results and Discussion
4.1. Rainfall dataFrequency analysis is an analysis of the repetition of an event to predict or determine the return period and its probability value.
Table 1. Average Rainfall Using the Thiesen Method in the Waterstat Canal Watershed
Year Date
Station Rain
Total (Mm) Ketintang Watutulis Durun
Bedug Prambon Coeffcint
0,217 0,291 0,284 0,207
2010 06-Mar 36,890 26,190 20,164 2,691 85,935
2011 15-Oct 31,031 36,375 41,712 33,120 148,238
2012 09-Nov 23,436 30,555 15,475 14,697 84,166
2013 05-Dec 36,890 32,010 14,200 31,464 114,564
2014 26-Mar 30,380 46,851 26,980 31,464 135,675
2015 27-Dec 21,700 21,243 15,620 20,286 78,849
2016 26-Nov 24,955 26,481 25,560 29,394 106,390
2017 17-Jun 34,069 49,470 31,240 22,770 137,549
2018 19-Nov 21,700 32,592 15,620 19,665 89,577
2019 12-Nov 18,445 43,650 46,860 13,869 123,824
2020 21-Jan 25,606 51,798 22,720 21,942 122,066
Source: Calculation Result
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Figure 3. Synthetic Unit Hydrograph Analysis Nakayasu Metode Method Table 3. Design Flood Debit with a 5-year return period
t(hour) U (t,1) (m3/dt)
Q Due to Net Rain (m3/dt) Q
flood (m3/dt
62,98 39,68 30,28 25,00 21,54 19,08
0 0 0 0
0,5 0,80 50,18749 0 50,19
1 4,21 264,8912 166,871 0 431,76
1,079 5,05 317,9208 200,2776 152,8404 0 671,04
1,1 4,96 312,5406 196,8882 150,2538 124,0318 0 783,71
1,5 3,54 222,9859 140,4723 107,2005 88,49203 76,26012 0 635,41 1,7 2,99 188,3489 118,6524 90,5487 74,7463 64,41441 57,0421 593,75 2 2,32 146,2148 92,10955 70,29275 58,02538 50,00476 44,28165 460,93 2,5 1,52 95,87496 60,39744 46,09187 38,048 32,78877 29,03606 302,24 2,6 1,44 90,48592 57,00256 43,50109 35,90936 30,94575 27,40397 285,25 2,8 1,28 80,8546 50,9352 38,87084 32,08717 27,65188 24,48709 254,89 3 1,15 72,24843 45,51366 34,73342 28,67181 24,70862 21,88068 227,76 3,5 0,87 54,53027 34,35192 26,21542 21,64035 18,64909 16,51468 171,90 4 0,65 41,1573 25,92747 19,78637 16,33328 14,0756 12,46463 129,74 4,645 0,45 28,62996 18,03575 13,76385 11,36181 9,791309 8,670682 90,25
4,7 0,44 27,97222 17,62139 13,44764 11,10078 9,566365 8,471483 88,18 5 0,39 24,6457 15,52582 11,84842 9,780651 8,42871 7,464034 77,69 5,5 0,32 19,95713 12,5722 9,594386 7,919991 6,825241 6,044084 62,91 6 0,26 16,16051 10,18048 7,769161 6,413301 5,526815 4,894265 50,94 7 0,17 10,59665 6,675474 5,09434 4,205285 3,624005 3,209233 33,40 8 0,11 6,948365 4,377196 3,340426 2,757461 2,376307 2104336 21,90 9 0,07 4,556134 2,870184 2,190361 1,808103 1,558176 1,379841 14,36 10 0,05 2,987517 1,882017 1,436248 1,185597 1,021716 0,90478 9,42 4.2. Calculation of Infiltration Well Needs
To calculate the need for infiltration wells, the following method is used:
H = Q
F.K[1 − e(−
FKT πR2)
] (3) With:
H: water level in the well (m)
F: geometric factor (m). Can be searched by means of F=5.5R Q: inlet water discharge (m3/s)
T: flow time (s)
K: coefficient of soil permeability (m/s) R: radius of well (m)
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One of the purposes of applying infiltration wells is to reduce surface runoff so as to avoid excessive surface runoff which can cause flooding. To determine the need for infiltration wells in an area, it can be seen from the flood discharge and the volume of flood runoff in the area.
Planning Data:
Geometry Factors = 5,5 𝜋R
= 5,5 x 3,14 x 0,5
= 8,635
Flood discharge plan (Qb) = 39,68 m3/det (I rain 5 year) Flood volume (Vb) = Qb x 3600 second
= 39,68 x 3600
= 142.848 m3
Permeability Coefficient (K) = 0,0023 cm/det Technical Data on Infiltration Wells Based on Lab Tests Width of Infiltration Wells (D) = 1,4 m
Fingers – Well Fingers (R) = 0,5
Well Depth = 2m
4.3. SNI Method 03-2453-2002
Calculating the wall area of the Well (Av)
Av = 0.25 x x D²
= 0.25 x 3.14 x 1.4²
= 1.5386 m2
Calculating the area of the well bottom (Ah)
Ah = 0.25 x D x H
= 0.25 x 1.4 x 2
= 0.7 m2
Calculating wall slope (Kh)
Kh = 1.2 m
Calculating the wall permeability coefficient (Kv)
Kv = 2 x Kh
= 2 x 1.2 = 2.4 m/s
Calculating infiltration well capacity (Vsr)
vsr = 0.25 x x D² x H
= 0.25 x 3.14 x 1.4² x 2
= 3.0772 m3
Flood share volume
Vab = 0,855 x Ctadah x Atadah x X5 = 0,855 x 0,7 x 25000 x 39,68
= 593.712m3
Absorbed water volume (Vrsp)
tc = 0.9 x X0.92 / 60
= 0.9 x 39,680.92 / 60
= 0.44 hours
K average = (K_v xA_h x K_h xA_v)/(A_v+ A_h ) =(2.4 x0.7x 1.2 x1.5386)/(1.5386 + 0.7)
=1.385m/day
Vrsp = t_c/24 x (Av+Ah) x K_rata = 0.44 / 24 x (1.5386 + 0.7) x 2.716
= 1.385 m3
Storage volume (VStorage) VStorage = Vab - Vrsp
= 593.712 – 1.385
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= 593,710 m3
Number of infiltration wells (n)
H total = (V_ab-V_rsp)/A_h
= (593.712 -1.385)/0.7
= 8.48.1 m
n = H total / H plan
= 8.48 / 2
= 4.24 pieces
Total volume of infiltration wells (Vtotal SR)
Vtotal = nx VSR
= 4.24 x 3.0772
= 13,04,8 m3
Infiltration well efficiency (ƞ)
️ = Vtotal / VStorage x 100%
= 13.04 / 593,710 x 100%
= 2.19%
5. Conclusion
1. Based on the survey at the location, the flow direction activities are towards the tertiary patusan which is in the south of the location. At the activity location, there is a run off of 262,961 m3/s.
2. The 5-year return flood discharge on the canal Waterstat is 783.06 m3/sec, while the canal Waterstat capacity with dimensions of 5400 m long, 12 m wide and 3 m deep is able to accommodate a discharge of 520.149 m3/sec, so the canal Waterstat at the activity location experiences overflow.
3. At the location of the activity, 4 infiltration wells are needed to reduce the runoff that occurs.
References
Chow, S. L. (1998). In Defense of the Construct Validity Approach. Theory & Psychology, 8(4), 481–487.
https://doi.org/10.1177/0959354398084003
Maria, A. (2012). Pengaruh Gaya Kepemimpinan, Pengembangan Sumber Daya Manusia dan Disiplin Kerja Terhadap Kinerja Pegawai Sekretariat Dewan Perwakilan Rakyat Daerah Provinsi Sulawesi Tengah.
Jurnal Katalogis, 1(1), 95–103. Retrieved from https://adoc.pub/agustin-maria-mahasiswa-program- studi-magister-manajemen-pas.html
Seyhan, E., Soenardi, P., & Sentot, S. (1990). Dasar-Dasar Hidrologi . Yogyakarta: Gadjah Mada University Press. Retrieved from https://opac.perpusnas.go.id/DetailOpac.aspx?id=464432
Wanielista, M. P. (1990). Hydrology and water quantity control. New York, NY (USA); John Wiley and Sons Inc.
Biography
Novita Lia Fitri,was born in Tulungagung City on November 14, 1996. The eldest of two children. The author completed his education at the State Elementary School VI Surabaya in 2009 and continued the Junior High School Taruna Jaya I Junior High School until 2012. Then continued the Ipiems Vocational High School until 2015 and enrolled at the University Narotama University Surabaya Civil Engineering Undergraduate Study Program, Faculty of Engineering and Computer Science. During my time at school, I was actively involved in organizations and in college I also took part in the Student Executive Board of Faculties and Universities. During my studies I also gained knowledge by participating in the "SINAR"
study group, namely Civil Narotama such as the Balsa Bridge Competition and the Earthquake Resistant Design Competition (ERDC) using balsa wood and also learning various kinds of software, SINAR is my second family. I am proud to be part of the SINAR team and I have gained valuable knowledge and experience.
