Hydroponic Coastal Mangroves: Sea Water Desalination | AEE 2022/23

HYDROPONIC

Clara Tian Yu Lie

COASTAL MANGROVES

CONTENTS

SITE

SITE

PROBLEMATICS

INFORMATION

GATHERING

INFOGRAPHICS

HYPOTHESIS DEVELOPMENT

HYPOTHESIS RESEARCH

PRE-TEST

DESIGN DEVELOPMENT

INITIAL DESIGN

HYPOTHESIS

ARTISTIC INTENTION

FINAL DESIGN

FABRICATION

PROTOTYPE COMPONENTS

COST BREAKDOWN

FIELDWORK

PROTOTYPE SITE

LOCAL MATERIALS

DEPLOYMENT

SCIENTIFIC TESTING/RESULTS

ACKNOWLEDGEMENTS

Jakarta, the capital city of Indonesia is one of the most densely populated cities in the world. With a population of 11.1 million, the city is a concrete jungle that struggles with climate change. Climate change has caused flooding and sea level rise to become a challenge for the residents of the city. Jakarta has also been projected to be completely submerged in water by 2050 as it is sinking at a rate of 1-15cm per year; with most of North Jakarta already sitting under sea level.

JAKARTA, INDONESIA

Sea level rise, mangrove forest degradation, land subsidence, and urbanisation contribute greatly to the exposure of coastal cities to threats which include flooding and soil erosion. These threats have caused great harm to coastal communities living in informal settlements. Many residents especially those living in informal settlements struggle to get out of poverty due to having no access to free clean water. The average amount spent on clean water from delivery trucks is approximately Rp 1,000,000 (US$71.10) over a third of their monthly income.

JAKARTA’S INFORMAL SETTLEMENTS

JAKARTA BAY

FLOODING DURING HIGH TIDE

3M HIGH CONCRETE SEA WALL

WATER TUBS

INFORMATION GATHERING

information gathering | INFOGRAPHIC

During the information gathering phase of the semester, we focused on gathering information on geography, landscape, climate, history, health, infrastructure and natural resources of Indonesia.

My infographic was on the urban development of Jakarta which was a great starting point in finding out what I was interested in to look into further during the hypothesis research phase.

hypothesis development | DESIGN EXPLORATION

hypothesis research | ELEMENTS OF INTEREST

Through research on Jakarta, these were some of the elements I found interesting and had the potential to develop. The intention of restoring mangroves along sea walls were also a key element I wanted to include in my project.

CONCRETE SEA WALL + MANGROVE RESTORATION + COCONUT WASTE

SEA LEVEL HIGHER THAN LAND

ABUNDANCE OF COCONUT WASTE

COASTAL FLOODING

MANGROVES COMPLEX ROOT STRUCTURE

THE CONCRETE SEA WALL

DENSITY OF MANGROVE FORESTS

HYPOTHESIS RESEARCH

GREY/WHITE MANGROVES

Roots: peg-like roots (pneumatophores) that stick out of the ground

Leaves: oval, pointed with a pale and slightly hairy underside

Desalination: grey mangroves desalinate by having salt glands that excrete salt mostly on the underside of the leaf; to reduce rate of evaporation.

BLACK MANGROVES

Roots: peg-like roots (pneumatophores) that stick out of the ground

Leaves: silvery green with a blunt tip

Desalination: black mangrove leaves form salt crystals on the surface.

hypothesis research | MANGROVE DESALINATION

Indonesia has the largest different types of mangrove species in the world and they are categorized as red, black and grey/white mangrove. Although all mangroves are able to desalinate water, these different types have different methods of excreting the excess salts.

RED MANGROVES

Roots: above ground prop roots

Leaves: large and broad with a blunt tip

Desalination: red mangroves desalinate water by directing salt towards ‘sacrificial’ leaves which turn yellow

*The most common species in Indonesia is the red mangrove

PROP ROOTS

PNEUMATOPHORES

hypothesis research | PRE-TESTING ON USING FRESH HUSKS FOR GROWTH

After doing plenty of research on the benefits of coconut husks as a nutrient source, I wanted to do some preliminary testings to decide whether I would like to move forward with this idea as well together with desalination. In the two weeks, the seed in tub with fresh husk added seemed to have grown slightly faster than the one without. Thus, I decided to add this as a secondary hypothesis for the project.

RED MANGROVES (RIZOPHORA MANGLE) FROM THE NETHERLANDS

USING COCONUT FIBRE AS THE PLANTING MEDIUM

USING THE LAMP TO GIVE IT LIGHT

FILLING 2 TUBS FOR THE COMPARISON TEST TESTING FRESH COCONUT HUSK AS A NUTRIENT SOURCE FOR GROWTH

design development |

INITIAL DESIGN

initial design | sketches

early sketches for the prototype based on the idea of creating a hydroponic mangrove system which explores the hexagon shape as the modular component. At this stage the hypothesis was still unclear but the sketches were done more for using the mangroves as a coastal defense to challenge the concrete sea wall in a way and also raise awareness on what urbanisation has taken from nature.

INITIAL DESIGN

INITIAL DESIGN WAS TOO COMPLICATED AND WAS DIFFICULT TO FABRICATE

1. initial prototype exploded iso

2. initial float components

3. initial prototype module iso

1.

1.1. Coconut fibre pot

1.2. Plastic water collection chamber

1.3. Rubber seal

1.5. Valve

1.4. Silicone tube

1.6. Mesh

2.

3.

2.1. M6 bolt

2.2. M8 bolt

3.1. Parang joint

Can a floating hydroponic mangrove system be used to desalinate sea water in coastal flood-prone settlements where the only barrier between land and sea is the sea wall, to provide those of lower income with access to free clean water for daily use?

the hydroponic mangrove system | FINAL DESIGN

1. float components exploded iso

2. float joint connection exploded iso

3. 1.6. vacuum formed plastic top float

thickness

1.5.

M8 bolt

M6 rubber gasket

1.1. M4 bolt

1.3. M4 rubber gasket

1.4. M4 nut

0.5mm

1.2. rubber gasket 1.5mm

thickness

thickness

FINAL DESIGN - FLOAT

FINAL DESIGN - WATER BAG

RAFIA ROPE

COCONUT FIBRE POT

COCONUT FIBRE ROPE

4.

4.1 40x40x50cm water bag

220gsm transparent tarpaulin

4.2 5cm tab with holes to attach to floats

220gsm transparent tarpaulin

4.3 Adjustable drawstring opening 5mm diameter rope

4.4 2cm diameter ring 200gsm transparent tarpaulin

4.5 coconut fibre rope

4.6 coconut fibre pot

4. Water bag section drawing

5. Water bag components

6. 1 module of floats and water bag

5.

6.

5.1 coconut fibre rope 8mm diameter

5.2 coconut fibre pot 15cm diameter

5.3 tarpaulin water bag 220gsm transparent

5.4 rope 5mm diameter

1. 11 water bags configuration

2800x1400mm

2800x2100mm

1.

2.

2. 9 water bags configuration

float mould fabrication | 3D PRINTING

The mould fabrication process was done with the top and bottom floats divided into three parts to accommodate to the 3D printing machine. The whole 3D printing was initially planned to take three days to complete with two mould being printed at the same time per day. However due to unforeseen circumstances (3D printer breaking down, mould not printing properly, etc.) the process took over a week to complete. Despite the troubles, since the top float mould was completed smoothly, the next stage of the float fabrication was able to happen together with the printing of the bottom float.

FABRICATION

float mould fabrication | VACUUM FORMING

The prototype includes 32 floats which required a total of 64 vacuum formed plastic pieces. This was done using the smaller illig machine with a bed area of 45cm x 50cm allowing for one mould to be vacuum formed at a time. The test float was done using 1mm thick transparent VIVAK plastic sheet which was later replaced by the one with 0.5mm thickness; due to having to make 64 floats and the 1mm sheets were more difficult to cut and it was unnecessary extra cost. The vacuum forming lasted over five days with about 12 floats done everyday.

VACUUM FORM TEST USING 1MM THICK PLASTIC

COOLING THE PLASTIC

64 PLASTIC FLOATS CUT AND DRILLED

PLASTIC FLOATS BEFORE CUTTING

ILLIG VACUUM FORMING MACHINE

INDENTATION CAUSED BY USING HOLLOW MOULD

FABRICATION

parang joints fabrication | LASER CUT

The float joints were made by laser cutting on a 1.5mm thick 50x50cm steel sheet. This created rough laser cut edges which were sanded down for a smoother finish. Despite being on the heavier end, steel was chosen over aluminium due to its strength properties over aluminium which would allow the slim joints to work and withstand the wave movements when in the field. This decision was made after consulting with experts in the metal workshop.

METAL LASER CUT - 50X50CM SHEET

SANDING ROUGH LASER CUT EDGES

SANDED PARANG JOINTS

4 FLOAT PARANG

2 FLOAT PARANG

3 FLOAT PARANG

FABRICATION

parang joints fabrication | POWDER COATING

Powder coating of the parang joints was the last step in the fabrication process. The parang joints were coated in orange powder to be able to stand out when in the field. Powder coating was also done to protect the steel from rusting when placed in sea water throughout the fieldwork. Two coats were given to all joints to ensure that they were well coated and protected.

POWDER COATING PARANG JOINTS

BAKING TO SET THE POWDER COAT

DRYING AND COOLING THE COATED JOINTS

ONE TUB USED TO COAT JOINTS TWICE

prototype | COMPONENTS TO BRING

1. Tarpaulin fabric cut to size for water bags [x11]

2. Top plastic float [x32]

3. Bottom plastic float [x32]

4. White 5mm diameter flagline ropes [3x20m]

5. Adhesive rubber gasket 3mm thick [32m]

6. 2 float parang joint [x12]

7. 3 float parang joint [x8]

8. 4 float parang joint [x10]

9. Miscellaneous screws

10. Rubber gasket set

11. Salinity refractometer

12. White reflective tape

13. Silicone hose 16x21mm [2m]

the hydroponic mangrove system | FIELDWORK

fieldwork | PROTOTYPE SITE

The prototype site is located on the inner side of the sea wall in Muara Baru port where the area is constantly flooded with sea water. This pool of water coincidentally has young mangroves planted in it which makes it an even more perfect site. Despite wanting to have the prototype sit on the outer side of the sea wall, the risks of strong waves and divers sabotaging the prototype were mentioned, and thus this site was suggested by one of the district administrator staff of Muara Baru.

Site coordinates: (-6.1006427, 106.8047560)

MUARA BARU PORT (-6.1006427, 106.8047560)

NORTH JAKARTA

WADUK PLUIT

PANTAI MUTIARA

MUARA BARU PORT

COLLECTION OF LOCAL MATERIALS

1st month

2nd month

3rd month

MANGROVE NURSERY - PANTAI INDAH KAPUK, NORTH JAKARTA

COLLECTING MANGROVES FOR THE PROTOTYPE MANGROVE SEEDLINGS

3-month-old rizophora mucronata

SITE EXPLORATION

POTENTIAL SITE 3

POTENTIAL SITE 2 MUARA BARU (-6.1109280, 106.8063110)

FISHING NET HUB (-6.1047206, 106.8053232)

POTENTIAL SITE 1 TAMAN WISATA ALAM ANGKE KAPUK

PROTOTYPE DEPLOYMENT

ATTACHING WATER BAGS TO FLOATS USING RAFIA ROPE

JOINING FLOATS IN SECTIONS INDOORS BEFORE GOING TO SITE

TRANSPORTING PROTOTYPE TO SITE

PUTTING THE WHOLE PROTOTYPE TOGETHER ON SITE

TYING THE COCONUT FIBRE POTS TO THE WATER BAGS

PROTOTYPE GOES INTO THE WATER

PLANTING THE MANGROVES

FILLING THE WATER BAGS WITH SEA WATER

FOUR MANGROVES

SINGLE MANGROVE

COCONUT WASTE

OUTER SEA WALL INNER SEA WALL

DRINKING WATER TAP WATER MANGROVE FOREST WATER

the hydroponic mangrove system | SCIENTIFIC TESTING/RESULTS

nutrient test | + FRESH COCONUT WASTE efficiency test | FOUR MANGROVES efficiency test | SINGLE MANGROVE

SCIENTIFIC RESULTS

scientific results | SALINITY READINGS

PROJECTED

scientific results | SALINITY

SCIENTIFIC RESULTS

PROJECTED OUTER SEA WALL

SINGLE MANGROVE

FOUR MANGROVES

PROJECTED MANGROVE FOREST

scientific results | TOTAL DISSOLVED SOLIDS

TDS value (ppm)

< 500 ppm

PROJECTED OUTER SEA WALL

SINGLE MANGROVE

FOUR MANGROVES

PROJECTED MANGROVE FOREST

500 ppm - acceptable tap water

the hydroponic mangrove system | ACKNOWLEDGEMENTS

MY FAMILY - FOR THE SUPPORT THROUGHT THE FIELDWORK PERIOD GRANDMA - FOR HELPING WITH SEWING THE WATER BAGS MR PAUNDRA - FOR GREAT INFORMATION ON MANGROVES MR RUBIMAN - FOR TRANSPORTATION

MR PADYUMI - HELPING WITH DEPLOYMENT AND TRANSPORT MR AGUS - PROVIDING INFORMATION AND TAKING US AROUND MUARA BARU MR RESJATI - PROVIDING EXPERT KNOWLEDGE ON MANGROVES

ARTHUR - DRONE PILOT

ALEX - VIDEOGRAPHER KT- SUPPORT

MR AGUS

ARCHITECTURE AND EXTREME ENVIRONEMENTS 2022/23