The Natoe Learning Centre (NLC) is located near the border with Myanmar in Mae Fah Luang district in Chiang Rai province. The centre is an initiative of the H.R.H. Princess Maha Chakri Sirindhorn to provide an educational opportunity for high school graduates from the Border Patrol Schools in the area. The vast majority of the people living in this region are from the various ethnic Hill Tribes. The aim of the centre is to educate the young Hill Tribe people so that they can gain meaningful employment when they graduate and thus avoid the poverty trap that has led many before into the drug and sex trades.
The learning centre is a satellite campus of the Chiang Rai College of Agriculture and Technology(CRCAT) on a limited budget with a small but dedicated group of teachers. The Sustainable Community Foundation was asked to help the centre with its water and access problems. This report will focus on the project designed to provide safe access across the Nam Kham River to learning centre.
The original crossing of the Nam Kham River into the NLC consisted of a wheel track down the banks of the river to shallows in the stream bed formed by river stones. Flooding in the wet season saw constant changes to the stream bed with washouts and large rocks proving to be obstacles that damaged vehicles after the water level had receded.
A number of options were considered including a pipe or box culvert, a bridge and a ford. Because the access road into the learning centre already crosses the Nam Kham River using a ford, it would be pointless to build a bridge or culvert at far greater expense as flood immunity would not be achieved.
A design of the ford was prepared using standard drawings from the Main Roads Department in Queensland the foundation’s program director and a funding proposal developed based on this design to go to the Vocational Education Commission. The original estimate was for project was 80,000 baht for materials. The submission was successful although the amount was reduced to 75,000 baht. Bringing the project in on budget proved to be a challenge as the ramps had to be extended to cover a previous attempt to construct the ramps that had not been well done. The foundation contributed 5,000 baht to cover the cost of materials and transport to ensure the completion of the project.
The project coincided with a visit by students from the Shawnigan Lake School in Canada who come on annual basis as part of their leadership program. There were ten Canadian students who were paired up with students from Natoe. The Canadian students were accompanied by two teachers who proved to be very professional and supportive.
The first task of the team was to fill the sand bags that were used to form a dam to keep half of the stream bed dry so that the concrete ford could be constructed in stages. The existing ford was re-aligned to allow vehicle access to continue in the early stages. It had been planned to have half of the gravel delivered to each side of the river to reduce the work load. Unfortunately the gravel did not arrive in time and it had to be placed on the entrance side of the river. This contributed greatly to the amount of effort required to pour the second stage of the project and included the mixing and placing of 7.2 cubic metres of concrete, all of which was transported up to thirty metres by a bucket line.
The first stage of the ford required 6.3 cubic metres of concrete with the final stage, the entrance ramp requiring 3.5 cubic metres of concrete. The total amount of concrete used was approximately 17 cubic metres, all of which was mixed by hand in a bag mix concrete mixer. A total of 16.5 cubic metres of gravel was used plus 119 x 50kg bags of cement were used in mixing the concrete. All of the sand for the project had to be won from the river bed to keep the project costs within budget as the cartage for sand and gravel from Mae Chan proved to be very expensive. More sand was also won for the construction of the administration building.
Two layers of steel were used for the project with a 12mm deformed reinforcing bar was used for the bottom layer and 10mm for the top layer with 50mm cover all round. The design depth of the slab was 200mm although this increased to 250mm in many places due to the size of the formwork being used and the nature of the existing river bed. Cut off walls were included on each side of the ford although digging down 600mm by hand in sand and gravel proved very difficult. The overall design was approved by Kru Pratya who also inspected the first stage prior to the pour. Kru Pratya is a Civil Engineer who teaches at the college.
The overall length of the ford is 22.3 metres with 12.2 metres being in the river flow. The ramps have a gradient of approximately seven degrees making for a gentle transition from slope of the river bank to the bed.
Special thanks for the successful completion of this project go the students of Shawnigan Lake and Natoe who toiled tirelessly for seven days. This thanks also goes to the teachers from Shawnigan Lake School who not only worked as tirelessly as the students but also displayed real professionalism and were fully supportive at all times. Two students from the main campus of the college also volunteered their time while on their term break and their construction skills and effort were very much appreciated. Thanks also go to the kitchen team who provided delicious food to the construction team. Meal breaks were always a welcome respite from the hard work that was undertaken at the crossing.
The ford not only represents a safe vehicle access for the majority of the year, it contributes health and well being of all present at the learning centre by enabling supplies to reach their destination easily and for sick or injured people to be transported to hospital without having to negotiate the rough river bed. Over time the upstream side will fill with sand making it easier to be won for future projects. No doubt the ford will also double as a car and motorcycle wash and many a small child will see it as a playground and a safe place to bathe.
The members of the Sustainable Community Foundation are pleased to have had the opportunity to have made an important contribution to the development of the NLC and the future of education of young Hill Tribe people in the region.
Note: A ford is a shallow place with good footing sometimes supplemented with concrete or asphalt for vehicles. where a river or stream may be crossed by wading or in a vehicle. A causeway is a road or railway route across a broad body of water or wetland raised up on an embankment.