ciencia e tecnica vol.31 no.2, 2016

7/25/2019 Ciencia E Tecnica Vol.31 No.2, 2016

1/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

32

RAINWATER MANAGEMENT FOR AGRICULTURE AND

LIFE IN THE HOUSEHOLD SCALE

Susilawati CL

Flores University, Sam Ratulangi, str., Ende, Flores 86316, NTT, Indonesia

ABSTRACT

East Nusatenggara Province has dried climate situation, which caused of the availability of water

for living very scarce. Some options have done do to this situation, for example by developing

many embung (small reservoir) or water-trap series along the gully as gully plug. The problemfurthermore comes related with the operation and maintenance of these structures. Thats also

happened for between each household place are far each other. Rainwater management in the

household scale would be the way to cope the scarcity for this condition. The principle concept is

managing the rainfall water on the household field by catching runoff with several Ferro-cement

structure to keep rainwater not to flow away out from household field and use for agriculture or

others. Rainfall water on the roof is managed by rainwater catches canal structure that completed

with mineralization and filtration structure so could use as clean water for life. This structure has

done as a model at 4 household in Tli'u village. As a result, they have water for agriculture activity

and life.

Keywords: rainwater management, agriculture, water for life, household scale

INTRODUCTION

East Nusatenggara Province has dried climate situation, so the availability

of water for living is very scarce (Susilawati, CL and Sooai, AG., 2012-b). Some

options have been done, for example by developing many embung (small

reservoir), (Kirmanto, D., 2011). Evaluations of embung systems development

also have been done, particularly in Sabu-Raijua Island, which includes: the

infrastructure system review, operations and maintenance, institutional,

community development, information systems and analysis of the benefits value.

It can be concluded that the development of embung systems in Sabu-Raijua

Island, have given some positive benefits. Several aspect need some attention,

especially on the technically infrastructure systems related to the proper target

planning services, charging condition of the water in the embung and the speed of

sedimentation rate. Less attention of the operation and maintenance system have

made the embung does not work anymore after a short time. Similarly, the limitedhuman resources make the institutional system very poor. Keeping in a well

planned community development, will be supporting the technical aspects, but

unfortunately also less attention as well. It can be said that the development of

embung system on the island of Sabu-Raijua looks like a central government

project, poor involvement of the local area officials, so is less support from local

people.

Attention to technical infrastructure systems or rainwater harvesting

system is urgently needed because the development of the existing embung has

less efficiency factor due to the evaporation and sedimentation occurs. To

overcome this case, it is necessary to consider the alternative water resources


2/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

33

development in this areas, which have a large evaporation and high sedimentation

rate, such as conservation reservoir that serves to capture rainwater, preserve it by

letting the water soak into the ground soils. Furthermore, it can be prepared dug

wells to extract the water that has infiltrated to ground water reservoir to giveavailable water for agriculture and daily used. This alternative water resource

development is given the term as rain water management for agriculture

(RWMA). This system emphasizes the term of "management" which means that

rain water managed optimally and has not just rain water harvesting. Likewise, it

is keeping in mind as well that the system management and maintenance has done

participatory by people as well to meet the sustainability of the system.

Since 2010, Susilawati has tried to promote the water-trap series along the

gully as gully plug to get more water for agriculture and domestic-municipal-

industry need. Based on the systems done by people in Daieko to get water by

holding water flowing in the grooves of the natural drainage system called aswater trap, that was developed a simple system to manage water as form as rain

water trap series such as simple embankments as gully plug (Susilawati CL,

2010). This system was developed to cope floods and droughts on small islands

(Susilawati CL, 2011). Furthermore, from the village of Daieko case studies, it

has developed for the entire island of Sabu (Susilawati CL, 2012-a). From the

observation of the reservoir system failure cause largely sedimentation due to the

cliffs erosion of reservoir design, the system was developed further by adding a

cliff reinforcement system with vetiver grass (Susilawati CL, 2013-a). Various

constraints have to be faced in implementing this system, especially concerning

financial terms. Furthermore, this system has been developed in household scale

(Susilawati CL, 2014), which was implemented in four families in the Tli'uvillage. The most constraint of this system is the operation and maintenance of

these structures (Susilawati CL, 2013-b). This obstacle strengthened again by

dwelling communities from each other. Fuelled by this experience, so was

developed of rain water management for agriculture and the need to live in a

household scale system. Thats also can be happened because of between each

household place are far each other (Fig. 1, 2 and 3). Rainwater management in the

household scale would be the way to cope the scarcity for this condition.

Figure 1 Tliu village imagery in 2004


3/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

34



RAINWATER MANAGEMENT CONCEPT

The principle of rainwater management concept is managing the rainfall

water on the household yard by catching runoff with several Ferro-cement

structure to keep rainwater not to flow out away from household yard and use that

for agriculture or others needs. Rainfall water on the roof are managed by

rainwater catches canal structure that completed with mineralization and filtration

structure so could use as clean water for life (Fig. 4).


4/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

35

Figure 4Rainwater management concept

RAINWATER MANAGEMENT FOR AGRICULTURE APPLICATION

MODEL AND LIFE IN THE HOUSEHOLD SCALE

This concept is being implemented in four households in the Tli'u Village.

Several water wells that trap rainwater are installed interconnected with each

other, so as to get the water accommodated, simply use the hand pump alone

without the need for energy. The hydrological analysis has to be done to get the

yearly rain for availability water. Table 1 shows the plotting position analysis.

Followed by the plotting position graphic (Fig. 5) and dry-normal-wet yearly

rainfall analysis (Table 2).

Several steps have to be done during the implementation of this model:

1. When to do the survey in the study location, it must be observe how the runoff

flowing, so that can be decided the location of the water well tank (Fig. 6)

2. Then the catchment area of rainwater are determined for each water well, so it

can be known the volume of rainwater which can be captured and stored in the

water wells

3. The next step is determined the dimensions of the catchment water wells in

accordance with the potential of rainwater that can be captured.

4. The final step is the design drawings of the catchment water wells.


5/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

36

Table 1 Plotting position analysis

Figure 5 Plotting position graphic

Table 2 Dry-normal-wet yearly rainfall analysis

No Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Des Total Rank Fa=100*m/(N+1)

1 1989 147 175 184 111 59 34 55 0 2 15 73 204 1059 2223 4.55

2 1990 380 229 205 67 62 2 0 0 0 0 0 454 1399 1951 9.093 1991 300 204 127 324 61 100 27 0 2 0 293 120 1558 1942 13.64

4 1992 302 130 235 99 50 51 0 0 0 0 126 373 1366 1886 18.18

5 1993 190 115 156 87 51 137 49 0 0 0 29 178 992 1827 22.73

6 1994 394 257 115 48 12 0 0 0 0 0 0 276 1102 1797 27.27

7 1995 137 228 147 163 0 15 0 0 94 104 322 293 1503 1691 31.82

8 1996 381 347 216 55 38 33 0 31 0 0 154 351 1606 1654 36.36

9 1997 381 632 86 13 21 0 34 0 0 0 49 438 1654 1606 40.91

10 1998 72 255 206 172 49 0 0 0 0 117 385 78 1334 1558 45.45

11 1999 545 199 342 380 7 23 0 0 0 41 236 169 1942 1518 50.00

12 2000 133 194 229 366 203 47 0 0 0 114 233 172 1691 1503 54.55

13 2002 315 205 114 122 0 0 0 0 0 0 98 229 1083 1399 59.09

14 2003 246 203 353 69 0 0 0 0 0 135 230 987 2223 1366 63.64

15 2004 247 487 462 27 129 23 0 0 0 0 62 390 1827 1334 68.1816 2009 545 199 342 380 7 0 0 6 0 0 178 140 1797 1102 72.73

17 2010 478 522 27 55 146 44 9 10 33 20 205 337 1886 1083 77.27

18 2011 365 295 341 354 64 8 0 0 0 9 112 403 1951 1076 81.82

19 2012 54 291 0 90 0 0 0 0 3 5 5 413 861 1059 86.36

20 2013 285 463 0 0 0 48 55 0 0 23 0 202 1076 992 90.91

21 2014 172 226 248 167 56 142 89 20 0 0 57 341 1518 861 95.45

Piav = 289 278.9 196.9 150 48.33 33.67 15.14 3.19 6.381 27.76 135.6 311.8

0

500

1000

1500

2000

2500

1.0010.00100.00

Bulan Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Des Total (mm)

Piwet 367 354 250 190 61 43 19 4 8 35 172 396 1,900

Pinor 309 298 211 160 52 36 16 3 7 30 145 333 1,600

Pidry 232 224 158 120 39 27 12 3 5 22 109 250 1,200

ETo 129 121 139 149 169 162 185 204 205 213 180 141 1,997

P80: Pdry = 1200 mm

P20: Pwet = 1900 mm

P50: Pnor = 1600 mm

Pav = 1496.6 mm


6/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

37

Figure 6 Runoff flowing and water well location of Mr. Benyamins yard

The field area for each house-hold and the catchment area for water well

are shown in Fig. 7-10.

Figure 7 Runoff flowing and water well location of Mr. Markuss yard

Figure 8 Runoff flowing and water well location of Mr. Hillers yard


7/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

38

Figure 9 Runoff flowing and water well location of Mr. Yusaks yard

Figure 10 Field area and catchment area for 4 house-hold

The construction of the water well contain of the Ferro-cement system as

figured as Figure 11.

Figure 11Ferro-cement water well system for rainwater captured and stored


8/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

39

The potential water which can be captured and stored is calculated as

shown in Table 3.

Table 3The potential rainwater which can be captured and stored to Ferro-cement

CONCLUSION

The household water needs can be met by developing of rain watermanagement system in the household scale. Even still have excessive water,

which can be used to meet the water needs of agriculture and other businesses. It

is suggested that the comparable between yard land area and family members,

must be considered in determining the capacity of rainwater well captured.

REFERENCES

Kirmanto, D., (2011). Guidelines for The Use of Water Resources.Regulation of

the Minister of Public Works No. 06/PRT/M/2011, 40-48.

Susilawati CL, (2010). Rainwater Management for Agriculture in Daieko VillageHawu Mehara District, Sabu-Raijua Regency, NTT Province. Journal

SIPIL UNWIRA,Vol 1 No.1, 51-58.

Susilawati CL, (2011). Water Resource Conservation with the System of Water-

trap Series to Cope Flood and Drought on Small Island, Journal SIPIL

UNWIRA,Vol 2 No.1, 30-38.

Susilawati CL, (2012-a). Rainwater Management Model Development for

Agriculture in the Savu Island Semi-Arid Region, Civil Engineering

Dimension Journal,Vol. 14 No. 1, 36-41.

Family Areal (m2) 2,000 1,500 1,280 mm

Yusak 302 Pwet Pnor Pdry Coeff = 60%

CA FC-01 128 15,360 11,520 9 ,830

CA FC-02 174 20,880 15,660 13,363

Benyamin 1187 m3 m3 m3

CA FC-01 444 53,280 39,960 34,099

CA FC-02 282 33,840 25,380 21,658

CA FC-03 461 55,320 41,490 35,405

Markus 1340 m3 m3 m3 drink 3.65 m3

CA FC-01 404 48,480 36,360 31,027 personal 18 m3

CA FC-02 478 57,360 43,020 36,710

CA FC-03 458 54,960 41,220 35,174

Hiller 1434 m3 m3 m3

CA FC-01 368 44,160 33,120 28,262

CA FC-02 412 49,440 37,080 31,642

CA FC-03 654 78,480 58,860 50,227

Yusak's family

water needs can

still be met

2 l/person/day

15 l/person/day

for drink

for personal

Requirement for 5

person per family


9/9

ISSN:0254-0223 Vol. 31 (n. 2, 2016)

40

Susilawati, CL and Sooai, AG., (2012-b). Rain-water Management System for

Agriculture during The Dry Season to Raise Food Security in Small and

Rural Islands of Indonesia.Research Report (competitive grant), Kupang.

Susilawati CL, (2013-a). Water-trap Series Engineering with Vetiver Grass in

Water Resources Development which are Integrated and Sustainable,

KoNTekS 7 Proceeding, A55-A63.

Susilawati CL, (2013-b). Study Implementation of Technological Innovation in

Addressing Problems of Water Resources Management in NTT, PIT-

HATHI 30 Proceeding, 112-121.

Susilawati CL, (2014). Sustainable Technology Innovation Inundated, Rain Water

Management Scope of Household,PIT-HATHI 31 Proceeding, 51-62.

ciencia e tecnica vol.31 no.2, 2016

Documents