We have been working for a long time towards creating an effective Quality Assurance / Quality Control (QA/QC) program. This began with choosing testing equipment that was low cost and could be fabricated at this post-apocalyptic looking shop here in Siem Reap. We decided to use a drive cylinder and a drop cone penetrometer.

Every layer of soil will be tested and approved prior to pilling a new layer on top. Chai, who is probably the coolest engineering student in Cambodia if not Southeast Asia, will be doing the testing and is becoming more comfortable with the equipment. We seem to attract an audience everyday while testing. But one of the unexpected results of this interest in the testing procedures is that the Contractor appears to now understand what we are testing and, hopefully, he will now be able to build to our specifications more efficiently.

Also, the sunsets at the construction site are pretty amazing.

soil samplin'

This phase of the construction requires keeping a keen eye on the type of soil being used for the fill material. The borrow location is inside the basin and was predetermined from our first site assessment last November. CMAC had finished clearing that area a few weeks ago.

Matt taking a look at the excavated borrow area.
Bryse scooping up a bowl for sampling.

Soil can be good at one location, then bad a few feet later. Every time the excavator dumps a heap into the truck, we must check that soil. For example, in one location, a 7’ deep pit yielded nothing but very sandy soil. After rejecting this pit, another one was dug about 50 yards away to find the pre-approved sandy silty loam sitting 5’ below ground. Sandy silty loam is more available in abundance in this area.

One can see the layers of the soil. The first 1’to2’ is organic material, followed by 2’to3’ of fine sands, followed by the approved fine sandy silty loam.

A closer look, Bryse holding the sandy silt loam in the left, and sandy soil on the right.

The soil was stove dried in the field, and varying moisture content bags were made to develop an intuitive understanding of how the soil feels at different moisture content. Shown above are bags with 8%, 10%, 12%, and 14% moisture content.

A long day in the field is followed by a long session of soil classification based on the Unified Soils Classification System (USCS). This requires sieving through a #10, #40, and #200 sieve, followed by performing the plastic and liquid limit (aka Atterberg Limits).

The soils lab was set up at our friendly guesthouse’s patio area and on top of the bbq grill.


The South Embankment

This first phase of repair work is on the existing West embankment but the South and North embankments need to be repaired in the later phases. The existing South embankment is not as big as the main West embankment. The photo above is where the south canal exits the reservoir and it's almost a perfect cross section of the embankment.

We are planning to install a small concrete water gate or a slightly modified box culvert at this South canal, like in the photo above, so the top of this South embankment can be used as a road and the water supplied to the canal can be controlled.

This photo is of the Tim and wiL taking a soil boring at the South embankment. We were boring in the dark last night, being eaten alive by giant mosquito's.


Staying in the Village

On Monday night we spent the night at Prom Kod, one of the villages in the Balang Commune. We were working on site that day until pretty late so by the time we showed up at the village it was already dark but Mean Someth was there with a huge smile to welcome us. We were directed to wash our feet at the well then we were brought into the house and served dinner. As we ate it looked like more and more people were coming to the porch to watch us eat so I took a picture and the flash illuminated an entire audience of smiling, curious villagers staring at us take every bite of our dinner.

We woke up early in the morning to the sound of farm animals then packed up and Someth led us back towards the site. On the way we climbed up to an ancient Angkorian ruin called Chao Seri Vibowl next to Wat Trach, a Buddhist pagoda. A small group of villagers arrived shortly after to pray. Someth sat down with them to explain who we were and the project we are working on. As we left the pagoda we bowed to the villagers and they smiled and thanked us. Tobias later explained to us that Someth grew up in Balang then left to start an NGO in Siem Reap and now has an almost celebrity status amongst the local villagers.


Mean Someth

Yesterday wiL, Tobias and I met with Mean Someth the director of Human Resource and Natural Development (HRND). Someth was the person that originally introduced the water gate project to Human Translation back in 2004. HRND has not been as involved with the technical aspects of the project but we discussed the surrounding communities involvement after completion. It was an inspiring meeting. Beyond the water gate, some of the projects HRND are working on are a rice bank, home gardening education, mirco-financing and there were discussions on future projects in language education and encouraging tourism in the area.
Our group has had many discussions about the Water Management Group; the people that will manage the maintenance and operation of the water gate and distribution of water stored in the reservoir. With the community connections developed by HRND it sounds like they are perfectly suited to help with the organization of this management group.



KAP is Kite Aerial Photography. A KAP jig would house a camera, and remote controlled servos would rotate, tilt, and also hit the shutter release button. Details on the KAP jig.

Here are some first images from KAP approximately 350' high. We were able to take many impressive soaring photos of the basin area. Shown above are photos looking west at the west embankment. You can see where the stream has breached through the embankment, causing a 60' wide gap. All of the vegetation and top soil has been cleared. The crest of the embankment is being leveled, and initial compaction has already begun. In the distance, you can see the downstream path, the small divisions of the rice patties, and the mountain Phnom Bok. Doing KAP was a 4 people effort. Chai was focused on flying the kite, Tobias manned the remote transmitter, wiL constantly had to untangle all the knots (somehow you ALWAYS get knots), and Bryse to stand in every downward shot with a pvc pole pointing North for point of reference and scale of photo.

Here's Chai feeding up the KAP unit. after a couple of trial and error, we figured out a strategy to get the unit up. attaching the unit too close to the kite causes difficult initial launching, since the wind at ground level is not usually as strong to lift the unit. launching the kite by itself for the initial 100' or so allows the kite to catch onto stronger winds above, hence, "locking" the kite up there. at this point, attaching the KAP unit to a newly tied knot will easily draw the entire unit up.

Left to right: two local spectators, Tobias controlling the remote, Chai teasing the kite, wiL feeding the line.


Some more pics from 'bodia

Before and After

These images are pretty small but we can't upload anything larger. But check out the difference in the site since the last site assessment! We were absolutely amazed at the pace of construction so far. wiL should get his Kit Ariel Photograph up and running tomorrow so we'll try to send some pics soon.


Photos 22 March 2007

Construction has started, and Bryse and wiL are in Cambodia. Here's a photo of the embankment progress. The contractor has nearly finished clearing the vegetation. They'll begin filling and compacting the embankment soon!


Next Week

wiL and I will be in Siem Reap in less than a week! I've been too busy to prepare myself for the culture shock but I'm really excited to eat weird food, meet all of the people involved with the project and see the site. HT emailed us that the Opening Ceremony is planned for this Saturday. We have a detailed schedule of activities but we're probably going to be completely overwhelmed with the embankment repair construction.
(this is one of Ryan's photos from the first trip)


Org Chart

During last weeks conference call, we discussed the organization of the project with Human Translation (HT). The important aspects of the organization chart is that the QA/QC person has a check on the Construction Manager, HT has the final word in any disputes between the two and, apparently, David reports to EWB.


Last Nights Concert

Last night's concert was a big success! It started with a decent crowd of EWBers and friends and turned into a legitimate concert with everything from great music to difficulty navigating through the crowd. Thanks again to everyone that worked on putting this really fun even together!


Site Survey

One aspect of this project that is still unknown is the volume of water this reservoir will typically hold. Apparently, the basin looks like a huge field and, other than the main embankment, the basin is surrounded by gradually inclining hills. This is one of the reasons we need a detailed site survey. We already have some topographic maps of the area but the entire reservoir fits between the contour lines provided.

By reviewing this detailed survey information with the annual rainfall data we are hoping to better understand the capacity of water this reservoir will provide to the surrounding canal systems. The next step will be a review of the canal system. A detailed survey of the canals would not be possible due to limited resources and safety concerns. However, our ideas for getting around a detailed survey of the entire canal system are first to find GPS points along the canals and second to use Kite Areal Photography (KAP) to photograph the system. (pretty excited about trying the KAP)

Design Update

We submitted a drawing set for the embankment repairs tonight. Construction for phase 1 should start pretty soon!

Following this phase, we'll return during the next dry season to repair the canal system and build the concrete water gate (phases 2 and 3).


Concert for Cambodia

Dan Garcia and Eddie Tadross have been working very hard for the past few months on putting together a benefit concert for the Cambodia project and the EWB-NY Chapter. After a long search of bars in Manhattan and Brooklyn they were able to get a ridiculously good deal at a place in the Lower East Side on a Saturday night. Plus, they signed up three bands and a DJ. There were many other members of the group that helped along the way and even more people are helping with all of the last minute preparations this week.

Here is the info on the concert:

Engineers Without Borders, New York Chapter presents:
Concert for Cambodia

Saturday, March 10 at Fontana's, 105 Eldridge St
Lower East Side of Manhattan
Doors open at 8PM; cost is $10 at the door

Meta and the Cornerstones
DJ Lechuga

Proceeds will help EWB-NY complete the Balang Dam and other projects.