Hey everyone! Sorry for the delay in updates. Currently we still need to hear back from the national chapter for their review of our assessment trip. If all goes well, we will be able to perform a pilot phase implementation trip in September, where we will be installing three (possibly four)composting latrines of varying designs in the Kukra River community of San Sebastian. These designs will help us in figuring out the optimum cost, and reliability, output product (fertilizer) among many other factors. Here are some rough designs that that we have come up with thus far. Many modifications will take place between now and September.





courtesy of James Chen


our trip will serve both as an assessment trip for the possible installation of roof water-catchment systems and as a pilot phase for our sanitation latrine construction project. For the pilot phase, we will be constructing three (possibly four, depending on the amount of funding that we acquire) composting latrines within the community of San Sebastian and along the outskirts of Las Brenas. All designs will be double-vault composting latrines of relatively similar size. Design #1 will be a simple, minimal cost design that is similar to the nearby composting latrines in the Kukra River Region. The main difference, however, lies in having a wooden staircase as opposed to cement.
The second design will be built partially in ground, utilizing the structural support provided by the earth in order to maximize the given volume. This latrine will have a cement staircase with a cement slab along one of the steps that can open up and serve as an opening for weekly stirring of the mixture as well as the annual removal of the compost. Such a design will essentially eliminate the issue of fecal contamination around the toilet seat area that could pose a potential problem during the typical practice of stirring through the toilet hole. This model will also be equipped with a zinc superstructure, which isn’t as widespread of a material choice as wood, however it has been used with a few of the latrines in the region.

The third design will implement an added section in the back that, again, seeks to maximize the volume below the latrine while still seeking to maintain both cost and effectiveness in the composting process. The area will have a slanted top face that contains a metal door which can open and close to allow for easy stirring and removal of fecal matter. The choice of metal is an attempt to speed up the anaerobic breakdown of the fecal matter through heating while also serving as a structurally robust moving component in our design. The staircase for this design will be wooden. This design will be constructed for one of our larger selected families that live on the outskirts of Las Brenas.

The potential fourth design will be quite similar to that of the third design with the exception of a more permanent, cement staircase and an additional ventilation system via PVC piping. Such a feature has the potential for helping to facilitate the anaerobic process within the fecal matter as well as reducing the instances of flies and negative odors. Ideally, this design will be constructed for the new schoolhouse that is to be constructed in San Sebastian (via financial support from the Catholic Church). Since such construction is still underway, this design is likewise still up in the air. During the assessment trip, we were assured by one of the teachers at the preexisting school that there would be members of the community that would be willing to take on the task of compost upkeep and removal, as ownership of a latrine in such an environment is quite different than with families.

Here are some photographs back from kid's day for Engineers Week (EWeek) at UCLA(taken April 8th). This event was a water relay race where children would race to carry buckets to an area where they would fish out the 'contaminents' and then return back to the finish line. The event was meant to essentially simulate the process that many children and corresponding family members in developing countries must go to in order to obtain usable water on a daily basis.

So our planned trip for return to Nicaragua was scheduled for early June, however, because of new policies imposed by the EWB national chapter, there now needs to be at least a 3 month leeway period between when we submit our pre-implementation forms and when we travel. Currently, we still have to complete the following before implementation travel: submission of post-assessment report (includes baseline health assessment as well as budget from the travel), TAC review to discuss our assessment trip, a 523 (alternative design) form, a 524 (preliminary design) form, and finally a 525 (pre-implementation) form. Our group will be working on all of these tasks in a joint effort.

As for now, here are some more photographs from our trip:

Today Engineers without Borders-UCLA participated in kid's day for Engineer's Week at UCLA. We held a relay race that involved kids carrying buckets of water with 'contaminants' and then having them remove the 'contaminants' with nets and returning back with the buckets of 'purified' water. This was the second time we've hosted this race and it was again a success. Tomorrow there will be club tabling with trivia challenge questions for people passing by. There will also be club tabling on Thursday.

In regards to the Nicaragua Sanitation Project, we are in the midst of the funding process and have a couple small school grants that we've been applying for.

Our group has also begun the design phase of this project and we have made a couple of alternative suggestions to the preexisting latrines in the area.

First off, as of now we wish to have piped ventilation for the benefits of odor reduction, fly removal, and quickening of drying time of the compost (due to the sunlight from the top of the pipe as well as the air ventilation that will be imposed (via bernoulli effect for a velocity/pressure gradient). This ventilation system will be modified so as to have the top of the pvc pipe caped with a piece of glass that will let sunlight through but not rain. To accomodate for the flies and air circulation, we will also have (attached to the main structure) a downwards pointing elbow joint along with fly paper.

Another important feature that is different from most dry latrines in the area is a completely separate urinal for the men. This can easily be constructed out of a large plastic bottle cut in half and some rubber tubing. The reason behind having a separate urinal is ease for the men as well as preventing any moisture getting into the vault.

Regardless of whether or not a separate urinal is built for the men, we will still have to deal with the issue of urine for women, which is why the current design (as pictured below) should still be implemented. The only difference we wish to have would be to shape the toilet seat in a manner that renders it compatable for having a conventional plastic toilet seat placed on top of it. This reduces the need for cleaning and allows for the families to better see and clean this unit (without the use of water, which often times drips into the vault.

The latrine design will also incorporate the use of wood wedging between the zinc roofing and the wooden structure. This wedging would serve the purpose of reducing any sideways rain from entering the unit.


We are still looking into the possibility of a "solar latrine" design. Further research is much needed on the subject matter.

Alternative designs/considerations: here is a link to a fiberglass latrine design (cost est. $500):
http://www.edusc.org/Forms/HaitiDryLatrineProject.pdf


-Julia

Alright everyone. So our goal right now is to shoot for constructing three composting latrines in the community of San Sebastian (and possibly as well as a house in between San Sebastian and Las Brenas). This will serve as our pilot project trip and will take place sometime in early summer (possibly between June 12-22 if not longer). During this trip we will also be conducting an additional in-depth site assessment for a potential water catchment system in the communities of Las Brenas and San Sebastian. We have already submitted water samples from the two communities for testing to be done by the university in Bluefields. We are currently awaiting the results.

-Julia

Here are some additional photographs from our trip:


This is a photograph of a typical separated dry latrine (taken from the FUNCOS building in Aurora). They used lime as their additive so the latrine not only did not smell bad, but it actually smelled good!


A woman washing her clothing in the river. For the people living in Kukra River, they use the river for washing clothing and for bathing. According to one of the doctors in Aurora, it is common to see women receiving vaginal infections due to bathing in this water.


The minihotel we stayed at in the central area. It had a good location, personal bathrooms in each room which included a shower with running water (though the water is cold and is actually quite contaminated in Bluefields), cable television with some really great channels, and there is a restaurant in the hotel to eat at (slightly overpriced).


Tim and I about to board the FUNCOS boat to travel up the Kukra River


Our plane from Managua to Bluefields

hey guys! We´re back in Managua after an exhausting journey to Kukra River. A lot of information has been discovered and gathered! First off, there actually already exists a strong presence of composting latrines in the communities! This makes our project a whole lot easier, but also leaves a lot more room for additional projects in these communities! We found quite a few possible areas for future projects, but it actually seems like water is the biggest issue (contrary to what Marvin had mentioned). We paid $40 to have water samples tested for the water quality in san sebastian as well as las breñas (the communities that had the biggest water issues). While in Kukra River, we hosted community meetings in each of the three communities and also interviews with family members. San Sebastian was the only community that did not already have composting latrines. Both Caño Azul and Las Breñas had composting, or ´dry´, latrines installed for a fair portion of families thanks to the accion medica christian group. We rode mules a fair portion of the time but due to liability issues, I think our future plans should not encompass this mode of transportation (as one of our team members had fallen off of the mule due to muddy conditions and could easily have been stepped on and severely injured if not killed). We also were able to acquire lots of information on material prices in bluefields (for both the dry latrines as well as a potential water catchment system). Anyways, like I said, a lot of information has been discovered and Warren, Tim, and I plan to discuss it all in detail at this next meeting. Photos will be uploaded shortly.

-Julia