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01 02 03
About Schedule of Activities
Event: Survey and Analysis
Photo Gallery
Day 1 Macro Discussion & Preparation Event Event Event Event
: Site Survey : Shop : Macro Discussion : Public Engagement
Day 2 Build Up Rain Garden Tool Event Event Event Event
: How To Make Rain Garden : Land Clearing : Meassuring : Planting : Creative Recycling 1
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ABOUT
# PROJECT - PARK Urban Guerrilla has initiated a series of workshops on a variety of subjects related to urbanism branded as the ‘5 TACTICS OF URBAN GUERRILLA TO OVERTURN THE CITY‘. As the name implies, there will be 5 workshops/projects with 5 different themes in the span of the next two years. This book will talk about the second project that was conducted in Surabaya on the 7th-8th of December, 2013. The theme of the workshop was ‘Park’. This event was divided into 2 acts: the first act was to build a garden that involved the local community with Urban Guerrilla as the main coordinator, and the second was a short discussion about macro frame work in “Water Harmonization and Surabaya City” with Tunas Nusa Foundation as the main coordinator. The first act involved around 30 local communities, while the second act was joined by more than 40 volunteers from different backgrounds. We would love to engage more participants and experts from different backgrounds at our next event. We’re looking forward to working with you!
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We thank our extraordinary participants – professionals, students, facilitators, local communities; who contributed to the second project with their wonderful energy. Ramalis Prihandana, Zaenal Arifin, Abah Raffi and Mbak Dian for their positive spirits and enormous support. Tunas Nusa, BKM, HMTL-ITS (Nurul, Budi, Bima, Eva and friends) for your great collaboration. Pak Lurah, Pak RW 04, Pak RT 02 and everyone who participated in this project with such enthusiasm. Last but not least, the Urban Guerrilla team for the solid urban spirit.
PARTICIPANTS • • • • •
Tunas Nusa Fondation Indonesia PIP2B (Pusat Informasi Pengembangan Pemukiman dan Bangunan) Jawa Timur PNPM Perkotaan – BKM Mitra Sejahtera Himpunan Mahasiswa Teknik Lingkungan (HMTL) Institut Teknologi Sepuluh November Warga RW 04 Tegal Mulyorejo Baru, Kelurahan Kejawen Putih Tambak, Surabaya
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Now the roadside is converted into a garden, not just a garden but a RAIN GARDEN! A garden that looks beautiful while also reducing runoff and conserving water.
Now we know the name of these plants because we labeled each plant!
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We planted a variety of herbs in the garden, so we can harvest them in the future!
Put more soil here and make it a land swale! That way, when it rains, the water will flow to the garden.
Later, we can use the water from the barrel for watering the plant.
Here comes the humus, good quality soil will improve the system!
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DATA COLLECTING
SCHEDULE OF ACTIVITIES Surabaya has been selected for the #2 project of Urban Guerilla Series in recognition of the successes of urban stakeholders and the government in improving the quality, function and quantity of green open space. Considering that water is the main element in Surabaya, we gathered information to find a way to infuse the issue of water supply into the parks. We found that creating simple rain gardens in a neighborhood scale might just be the solution we need!
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17 NOVEMBER
18 NOVEMBER
Public Park Survey
Green Kampoeng Survey
• • •
Taman Flora Taman Bungkul Taman Prestasi
• • • •
Gundih Morekrembangan Jambangan Kejawan Putih Tambak
SITE S
2 DECEMBER • •
Land Measurement Tools and Material Survey
SURVEY
3 DECEMBER •
•
Building Relationship with Partners Community Engagement
DAY 1
7 DECEMBER
Site Preparation 10.00-14.00
All participants gather in RT 02 site to discuss and check all the preparations that need to be done for Public Counseling and Implementation Day. Allocating the hard materials and plants near the site. Work specialization to coordinate certain tasks.
Macro Discussion “Water Harmonization and Surabaya City” 15.00 – 18.30
DAY 2
8 DECEMBER
Implementation “Building the Rain Garden” 06.00-15.00 We started work on the selected site by clearing the land, digging and eventually planting. The UG team finished our tasks and officially handed the gardens over to the community, so that they can tend to it and eventually reap the benefits of their rain garden
This session began by discussing Surabaya as a dialogue platform, where we looked at the history, current conditions and the future development challenges of Surabaya. The discussion also compared a case study from Singapore and Australia regarding urban water strategy to Surabaya’s Urban Hydrology.
Public Counseling about rain garden 19.30-21.00 Our target was to expose the local community to the benefits of having a Rain Garden. During the counseling, we managed to receive public attention and discuss their concerns about implementing the garden, technical issues and the garden’s maintenance in the future
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EVENT: SURVEY & ANALYSIS Surabaya Surabaya, the capital of East Java province, is also the second largest city in Indonesia. With a population of over 3 million and a density of around 8,300/km2, there is no doubt that Surabaya, with its year-round climate being 22-31° C , gives the impression of being a (very) hot metropolitan city. Surabaya is considerably accomplished in the field of environment. The city has won the Adipura trophy three years in a row from 2011 to 2013 in the metropolitan city category. The rain gardens have great potentials to improve the value of the environment for the people of Surabaya, whose activities revolve around parks. • • • • •
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Site survey in Tegal Mulyorejo Baru - along the road Site survey in Tegal Mulyorejo Baru- river condition Survey for local plants in nursery market - Pasar Bunga Bratang Survey for local material Site survey in Jambangan - Green Kampung Winner, Surabaya Green and Clean 2012
A
B
C
Survey of Surabaya City Park
Survey of Surabaya Green Kampong
Nursery Survey in Pasar Bunga Bratang
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Survey of Surabaya City Park Several years ago, Surabaya might have been known as a hot, humid, dirty and polluted city. However, since 2006, Surabaya has been turning into a green city. Nowadays, Surabaya is known as the million-park city, due to the ample development of beautiful parks around the city. There are 11 parks in the city which have different themes, such as the Senior Citizen Park (Taman Lansia), the Friendship Park (Taman Persahabatan), the Expression Park (Taman Ekspresi), the Skating and BMX Park (Taman Skate & BMX), the Flora Park (Taman Flora) and various other beautiful parks. Additionally, these parks are also equipped with Wi-Fi, libraries as well as fitness and climbing facilities that people can fully enjoy while using the park. http://projectingindonesia.com/
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A
01
02 The Bungkul City Park
Taman Flora
Recently won the 2013 United Nations Asian Townscape Award presented by UN Habitat Regional Office for Asia and the Pacific, the Asia Habitat Society, the Asia Townscape Design Society, and the Fukuoka Asia Urban Research Center.
Is known as a free public recreation destination, as well as a place to hold outbound activities.
04
03 Taman Prestasi,
Taman Flora
Holds folk culture events like Kuda Lumping performances during the weekend as well as other events and facilities geared towards the younger crowd.
Has a seedling garden for students.
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Survey of Surabaya Green Kampoeng One of the government programs revolving around the Surabaya Green and Clean concept is the Clean Kampung competition. Started in 2005 in order to improve the quality of environmental in kampoengs, it’s become a huge success. As a result, many kampoengs have improved significantly in health and cleanliness. In the event, each Kampoeng need to demonstrate the excellence of their Kampoeng in the following aspects : * Preparation * Environment Makeover * Community Participation
5 categories that will be in charge as the winner : # Most Innovative Kampoeng # Flowery Kampoeng # Community Participation # Best Waste Water Treatment Plant (WWTP) # Best of The Best Kampoeng
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B
01
02 Kampoeng Jambangan
Alley along Kampoeng Jambangan
Has become a tourism kampoeng due to its successful management of the environment.
Has been decorated with pots, hanging plants and murals on the walls.
04
03 Kampoeng Gundih Has implemented a simple but effective water sewage treatment plan.
Urban farming in Kampoeng Gundih Enables people to harvest long bean, chilli, tomatoes, eggplant regularly. 13
Survey Local Plants in Pasar Bunga Bratang Looking for indigenous plants in Pasar Bunga Bratang was a very pleasant experience. A traditional flower market erected in the 1980s, Pasar Bunga Bratang carries a large variety of spices and herbs in their shops.
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C
01
02
There are more than 65 sellers offering various type of plants, gardening materials and kits in here.
Often, sellers also offer a garden buildings service.
04
03
The environment at the flower market is shady and cool.
Colorful flower plants in pots.
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Day 1 16
Site Survey
Shop
Checking the current condition of the project site and its significance to residents, including their social requirements and potential construction methods.
Starting to check off the shopping list for materials and tools that were needed such as pipe, plants, wire, composts etc.
Macro Discussion In the afternoon, an interactive discussion on the water system in Surabaya was held between stakeholders such as academics, NGO, goverment, private agencies.
Public Engagement In the evening, we held a counseling/seminar with the local community in Tegal Mulyoreja Baru in order to give them a better understanding on rain gardens and their construction, functions and benefits.
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Site Survey 18
We observed that areas along the river are usually used as communal space, storage, or parking. For our project, we needed sites without large trees, so we chose a piece of land in RT 02 that looked suitable for our rain garden.
As we worked to translate the ideas into a design, we found that it was important to develop an understanding the site, especially its current condition and its significance to residents, its social requirements, and the potential construction methods. We spent some time in RW 04 Tegal Mulyorejo Baru briefly observing everyday life and talking to local residents to understand how they build and maintain their community.
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Do & Don’t Places for Rain Gardens
Places to avoid Rain Gardens
•
•
• •
• •
• •
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Where it improves the appearance of your home. Rain gardens can provide attractive visual buffers from roads or neighboring homes. Where an overflow can direct water safely away from the home and neighboring property. Where water drains to the garden by gravity. While it is possible to pump water up to a rain garden, this will increase costs and maintenance. The location of the park is located in the region preferred by the water system in Surabaya. Preferably located in areas that already have a community structure that has been built and managed properly. It is expected to have a drive and a community which can be facilitated. It has an area of approximately 25 m2 with the legal status of the land (to be sustainable). The location of the park can be located on the edge of a body of water in the border area and close to population centers.
•
•
• •
Over a septic drain field or tank. If uphill of a septic system provide at least 50 feet between rain Garden and the septic system over shallow utilities. Be careful to locate (and mark) all utilities before digging. Utility companies will come to your property to locate power, gas, phone and water, so call before you dig. Near the edge of steep slopes or bluffs. The additional water soaking into the ground on steep slopes can cause landslides or unwanted settling. In general slopes should be less than 15% for a conventional rain garden. If the rain garden is within 50 feet of a slope that is more than 15% consult with a geotechnical or geologic engineer. In low spots that do not drain well. These areas may be helpful for slowing and storing stormwater on your property, but poor draining depressions will not support typical rain garden plants and soils within 10 feet of a building foundation to avoid water getting into basements and crawl spaces.
So, you’ve found a good location for the rain garden. What’s next? Before sizing and figuring out the design details, the next step is to test the soil and find out how well the area drains.
Soil test Testing soil drainage is best performed in the rainy season. The test includes digging a hole, filling the hole with water and timing how long it takes to drain. If water seeps into the hole while digging and stays there, then the area has high ground water and is not a good location for a rain garden. If water does not seep into the hole, then continue. Note: It’s OK to do an infiltration test in the drier months as long as you are confident that the area does not have groundwater near the surface during the rainy season.Three steps to perform the test: 1. 2.
If the soil is moist, put some in the palm of your hand and try to squeeze it into a ball. Note:if the soil falls apart or can be broken up easily and is gritty feeling (suggests a sandier well-draining soil) or if it is sticky, smooth and forms a ball that can work like modeling clay (suggests poor-draining soil with higher clay con¬tent). If the soil is smooth but not sticky then it is likely a salty soil and moderate to poor-draining. If the soil is dry, add water a few drops at a time, break down the chunks to work the water into soil, and perform the test described above.
Dig a small hole about two feet deep and 1-2 feet in diameter. A bigger hole is OK if you have a backhoe or mini-excavator. As you dig, and before adding water to the hole to test drainage, observe the characteristics of the soil.Record your observations.These observations will help determine how the rain garden is constructed in the next section.
Locate Soil texture is determined by the amount of sand, silt and clay in the soil. The mix of these components affects how well the soil drains, and how well it holds water and nutrients for plants to use.
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Shopping 22
To prepare the logistics for the next day, we went to one of the biggest nursery in the city to hunt for the plants on our list.
Learning about local construction methods and materials was essential in creating a feasible design. Since Surabaya is acknowledged as the million-park city, we assumed that Surabaya’s citizens must be seasoned gardeners. For us, it was essential that this event served to facilitate the sharing of knowledge between the people and the designers.
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Plant
IN THIS SECTION: Selecting plants by zone, mulching, sample planting plans, plant lists.
Selecting plants by zones In a rain garden, the plants and soil work together. The plant roots and soil organisms build soil structure, creating channels and pores to soak up and filter water while allowing nutrients and oxygen to flow in to support an abundance of life. While plants help the rain garden absorb stormwater, they also create an attractive landscape for your yard and neighborhood.
Rain gardens generally have three planting zones characterized by wetness. Select plants according to their water needs and sun exposure for these planting zones. Use a variety of small trees, shrubs, herbs, or grasses.
Plant
0.1 m
Mulch ( t : 0.1 m)
Mix Soil ( t : 0.65 m)
1m
Geotextile Crushed Gravel (t : 0.15 m) Pipe (d : 0.1 m)
Recommended Plants •
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Select plants that enhance the area and have appropriate water needs (native plants and hardy cultivars are preferred). We provide a list of plants that can be grown in rain gardens, although the list is not exhaustive, it gives a good guide to selection.
•
Rain gardens are NOT wetlands. Rain gardens are designed for short periods of saturation and are too dry for wetland plants, reeds and water lilies. Rain gardens require plants that can stand brief periods of water inundation.
SCRUB
Capsicum frutescens Cabai Rawit
Citrus hytrix Jeruk Purut
Gardenia augusta Kaca Piring
Scuropus anorogynus Pohon Katuk
GROUND COVER
Cymbopogon citratus Sereh
Xitriveria zizanoides Akar Wangi
Orthosipon aristatus Kumis kucing
Lavandula angustifolia Lavender
Alternantera amdenavoss Bayam Merah
Juticia gendarussa burm Gandarusa
Andrographis paniculata Sambiloto
Gynura procumbens Sambung Nyawa
Gynura segetum Daun dewa
VINE
Anredera cordifolia steenis Binahong
Piper betle Sirih
Basella rubra Gendola
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Macro Discussion 26
We had Mrs. Anggrahini, professor from ITS, talking about the hidrology of Surabaya; Mrs. Rita Padawangi, a researcher from NUS, talking about ABC Water Singapore; and Mr. Peter Dalkeith and Mr. Sibarani from AECOM, talking about various projects involving Water Sensitive Urban Design.
The day prior to the fieldwork, we carried out a major discussion inviting stake holders of Surabaya such as academics, NGO, government, and private agencies. The discussion was about the water system in Surabaya and how to solve the problems related to it. We discovered that almost 70% of Surabaya’s land area is below sea level, so it faces constant threats of flooding. To alleviate that problem, we believe that our Rain Garden project can be a solution to help reduce residential runoffs of water.
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Surabaya as Water City AREA
33,048 hectares
Surabaya Administrative Area
10%
500 hectares
Additional extension of river or coastal sedimentation land on the east coast of the city
3,000 hectares
Area of Gresik and Sidoarjo contributing to the water runoffs Surabaya receives.
Surabaya’s existing conditions: consisting of mostly lower lands, bordering the Strait of Madura on both sides and being located on the estuaries of the Brantas river; make Surabaya prone to problems such as flooding and seawater intrusion.
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Surabaya’s western districts lie 10-20m above sea level.
80%
of Surabaya’s northern and eastern coastal areas lie 0-3m above sea level. Some areas are even below sea level at high tide.
SOIL TYPE Alluvial soil is a relatively impermeable type of soil (low hydraulic conductivity), which doesn’t allow much water infiltration.
10%
Almost the entire city lies 0.5 m below sea level. Depth of the water table in coastal areas, leaving little for land absorption considering the maximum rainfall.
0-10 meters above the sea level.
Alluvial 0.50 meter 0.90 meter
CLIMATE CONDITION Average monthly temperature
Humidity in Surabaya City
Average annual precipitation (Tanjung Perak Station)
o
o
20 celcius -34 66 -percent 80 1560 mm 29
Water Management & Environmental Philosophy
1
condensation
transpiration
precipitation
precipitation
2 3
infiltration percolation
surface runoff evaporation
4
ground water flow
water table
1 2
5
seawater turns into freshwater in the process freshwater conservation in the terrestrial system 3 maximize infiltration 4 minimize surface runoff 5 maximize retention of rain water as ground water
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interception
lake water table
river
ground water flow
5
ocean
POST-URBAN
Post-urban Pavement & rooftops shed water 2 Storm drains deliver water directly to waterways 3 Streets act as streams. collecting stormwater and channeling it into waterways 4 Pollutants collected on impervious surfaces are washed into streams, rivers and lakes 1
2
a
3 b Pollutants collected on impervious surfaces are washed into streams, rivers and lakes
FF
Water pools in indentations filter into the soil Roots anchor soil, minimizing erosion
1
NO
a b
Vegetation helps build organic, absorbent soil
RU
Pro-urban
PRE-URBAN
4
Roots anchor soil, minimizing erosion
California, USA
POST-URBAN RUNOFF FLOW
PRE-URBAN > RUNOFF FLOW
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Illustration of Managerial Implementation Based on Natural Structure Post Urban without hard cover and vegetation / road
Kontrol : Pre-Urban
A
B
40% Evapo-Transpiration
35% Evapo Transpiration 30% Runoff
10% Runoff
25%
20%
25% Deep
Shallow Infiltration
Shallow Infiltration
Infiltration
38% Evapo Transpiration
Natural Ground Cover
Post Urban with vegetation and paving stone
C 20% Runoff
21% Shallow Infiltration
21% Deep Infiltration
10-20 % Impervious Surface 32
15%
Deep Infiltration
Efforts to prevent storm water runoff back into the drains.
The ecosystem-based integrated urban drainage management (eco drain) aims to prevent flooding and other environmental risks through the following steps:
Retention pattern •
T
R
Tampung (T) “Capacity”
Resapkan (R) “Absorb”
A Alirkan (A) “Circulate”
P Perawatan (P) “Maintain”
so that does not cause flooding and risk to the environment.
Containing water in basins or within soil (e.g. making infiltration wells, channels, fields or ponds) Retention pond
Drainage Pattern • Based On Environmental Management Detention pattern (TRAP) • Holding water temporarily (e.g. making storage ponds) • Detention pond
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Public Engagement 34
After introducing members of the Urban Guerrilla team, we continued to our interactive presentation session. During the presentation, the audience were free to ask any questions or present any concerns they had to the team.
In the evening, we held a counseling/ seminar with the local community in Tegal Mulyoreja Baru to prepare for the next day. We discussed the concept of the rain garden, its benefits, its function as well as its construction method.
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Rain Garden What is Rain Garden ?
Run off from road
Run off from house
A planted depression that can collect, soak up, and filter stormwater runoff from roofs, driveways, streets, parking lots and other hard surfaces.
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A rain garden is Why Make a Rain Garden ? designed to merge two important aspects: aesthetics and water quality. Rain gardens are also known as bio-retention areas and are intended to be an attractive landscaped area that treats storm water runoff. Without rain gardens, storm water quickly moves into streams and lakes, polluting our water ways. Water is directed into the rain garden by pipes, swales or kerbed openings while the garden acts as a depression that temporarily holds water. These gardens can collect, soak up, and filter stormwater runoff from roofs, driveways, streets, parking lots and other hard surfaces.
We need quality water. In 2009, only 58,2% of the water entering our waterways were clean.
We need affordable clean water. With more clean water available, we can generate reasonable prices.
We need to be more aware of our water. Hidden water infrastructure doesn’t help us understand or improve our relationship with water.
We need permeable surfaces. Concrete and asphalt surfaces inhibit the absoption of water into the ground.
Rain gardens are very effective at removing the most critical pollutants from stormwater. Rain gardens are planted with watertolerant trees, shrubs and grasses. Rain gardens can vary in size, depending on the area that drains to it and the type of soil in which the garden is built. A rain garden is designed to merge two important goals: aesthetics and water quality.
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Benefit of Rain Garden Water is an important element in human life. While water consumption needs in the city is very high, the availability of clean water nowadays is declining. Rain gardens is one of the solutions that prevent pollutants from entering our water supplies while also helping to reduce floods. By containing, absorbing and filtering the water, we improve our water quality with a simple, effective and beautiful solution. • • • • • •
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Reduce flooding Remove Pollutants Replenish Ground Water Reduce stormwater runoff Improve water quality Replenish groundwater
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HowRain
Garden Work ?? There are three principal parts to a rain garden :
The drainage area, which is comprised of drainage
pipe and washed stone. The depth of the drainage area should be between 150mm and 300mm, depending on the type and size of the drainage pipe used. Typically 100mm – 150mm diameter corrugated plastic pipes with slotted holes are used. The number and type depends on how much water is entering the rain garden and how fast it needs to be removed. Pipes must be selected so that they drain water within the top 600mm of the surface within 48 hours of rainfall. Between the rock layer and the soil, a permeable geotextile is placed, which allows water to pass through but keeps the soil separated from the rock layer.
The soil zone
, where the plants take root and most of the water treatment takes place. The soil zone should be at least 1.0m deep, though 1.5m deep is preferable. If the soil is very heavy clay, it will need to be mixed with sandy soil to achieve a permeability of approximately 75mm per hour. The rate that water moves through soil can be estimated by using Darcy’s Law:
Rain water
Public Water System
Garden
q = K^H/L where q = flow per cross sectional area, K is hydraulic conductivity, H is change in head or height of water, and L is thickness of soil layer. Usually, H and L are almost the same so the rate of water can be estimated by q=K.
The vegetation and mulch zone, which is
the visible part of the rain garden. Mulch should be at least 75mm thick and replaced regularly to keep it fresh and the plants must be water tolerant. If the flow of water is strong into the rain garden, place rocks in the surface at the inlet point to dissipate the energy of the water and prevent erosion and plant loss. 40
Proccess Water Catchment Area
Infiltration
Ground Water
Work System of Rain Garden Without pipe Water will filtrate to the ground after being filtered by the garden layers.
Process of cleanning the pollutant
Plants Mixed soil Sand : Compost : Loose Soil Gravel
With pipe
Process of cleanning the pollutant
Geotextile and pipe are needed if we want to collect the water that has been filtered by the garden layers.
Plants Mixed soil Sand : Compost : Loose Soil Gravel Geo-textile 41 Pipe
Samples of Rain Garden Projects The first rain gardens were created to mimic the natural water retention areas that occurred naturally before the development of an area. Rain gardens, or bioretention systems, were first conceived in 1990 by stormwater specialists in the state of Maryland, USA. This is also referred to as Water Sensitive Urban Design (WSUD) in Australia and Low Impact Development (LID) in United States. Since then, thousands of people, municipalities and organizations have influenced and enhanced the rain garden movement, especially in developed countries. www.raingardens.org
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Australia Healthy Waterways Raingardens Program promotes a simple and effective form of stormwater treatment, and aims to raise peoples’ awareness about how good stormwater management contributes to healthy waterways. The program encourages people to build rain gardens at home, and has achieved its target is to see 10,000 rain gardens built across Melbourne by 2013.
UK Islington London Borough Council commissioned sustainable drainage consultants to design a pilot rain garden in the Ashby Grove development which was completed in 2011. This raingarden is fed from a typical modest domestic roof catchment area of 30m² and is designed to demonstrate how simple and cost effective domestic rain gardens are to install.
USA Maplewood, Minnesota has implemented a policy of encouraging residents to install rain gardens. Many neighborhoods had swales added to each property, but installation of a garden at the swale was voluntary.
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Day 2
Land Clearing
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Measuring
Planting
Creative Recycle Ceremonial
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How to Make Rain Garden Materials 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Sand Compost Crushed gravel Loose soil Mulch Pipe (D:100 mm) Pipe connector Barrel (to collect the water) Geotextile : Filter layer Nail Timber paint Plants
Tools 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
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Hammer Pipe saw Timber saw Hoe Brush Crowbar Shovel Water pipe String Tape measure Rope Drill
Steps ! 1
2
Determine rain garden location. Make sure the direction of water flow to the location and consider soil type.
Calculate the area for the next calculated of the material needs.
5
6 7 8
3
Land clearing and materials preparation.
9 10
4
Place the drainage pipe. Make sure the slope is 2-3% , it is intended to allow water to flow.
Fill with gravel (-+ 150mm) -+ 0.5 m depth, and gravel thickness above the pipe is at least 50mm.
Place geotextile on top of the gravel. Geotextile aims to filter the particles that enter the pipe along with the water.
9 8
Fill with mixed soil -+ 0.75 m. The ratio is 2:1:1 for Sand : Compost: Loose Soil.
7
Start to plant.
Cover with medium mulch size (wood chips) Make sure the depth is -+ 0.2 m.
Dig an area of about 1 m depth and condense the base.
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Rain Garden Layout The rain garden is designed to be beautiful; so color, texture and size are important to consider when selecting. Local plants that perform appropriately are preferred so consult with nurseries and landscape professionals to choose the right plants.
The layout below can be matched sequentially with the list of plants we have provided.
Planting must be regularly maintained and inspected after rainfall to ensure survival.
Costs for a Rain Garden The cost for a rain garden is dependent on 4 factors. • • • •
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The type of soil. This dictates the cost of excavating, hauling, installing pipes, and importing new soil and rocks. The topography (flat or sloping). A flat area is best for construction the body of the rain garden. The types of plants selected, The number, species and size of plants affects the total cost of planting. The required surface area. The bigger the area the higher the cost.
Rp 100,000 Rp 300,000 / m
2
Design & Build 1. 2. 3. 4. 5. 6. 7. 8.
Determine the size and shape of the rain garden. Excavate soil (18-30 inches typical). Level bottom of rain garden (do not compact). Mix compost with soil. Place soil mix and leave at least 6 inches below edge of rain garden for ponding. Level surface of soil. Create an entry for water (swale, pipe or landscape area) into rain garden. Provide a rock-lined overflow.
Pilot Project Dimension :L 6 m x W 1 m x D 1 m along the road and riverside
1m
10 m
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Land Clearing 50
We started to work early in the morning at 6.30 am. The first things to do was clearing the land. There were so many leftover building materials there which can be recycled, such as gravel and wood scraps.
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Measuring 52
With the amount and size of the materials that we had, we dug a hole, 7 meters long, 1 meter wide, and 1 meter deep. Inside, we managed to fit a 5 meter long pipe and a water drum.
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Planting 54
One of the funnest step was planting. All the children were very excited to contribute; they planted the herbs, covered them with mulch and finished by watering them.
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Creative Recycling 56
Spontaneous action happened there when we found unused wood scraps. We recycled the scraps to be plant labels. We though this might be a fun way of informing children the name and use of each plant.
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Event Ceremonial 58
At the end of the event, the UG team passed the torch and handed over the rain garden to the local community. We hope that in the future, they can maintain and benefit from the garden.
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Before
After
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61
03
PHOTO GALLERY
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