MeghanHeintz (talk | contribs) m (→First Flush) |
MeghanHeintz (talk | contribs) |
||
| Line 85: | Line 85: | ||
====Filters==== | ====Filters==== | ||
Due to the community | Due to the community desire for the rainwater to become potable, filters were required. After research and considerations, we chose to use a slow sand filter and a activated carbon with silver filter. We chose the filters by considering what was required of the water, as well as the cost of the filter and local materials use in the filter. Our slow sand filter was then placed on a 5 ft metal brace and attached to the wall to prevent theft and hurricane issues. Below the slow sand filter, our final filter, an activated carbon and silver filter, was connected and attached to the wall. This filter occurs just before the spigot, where the community is able to collect water. | ||
=====Slow Sand===== | =====Slow Sand===== | ||
| Line 92: | Line 92: | ||
=====Activated Carbon with Silver===== | =====Activated Carbon with Silver===== | ||
We also used an activated carbon with silver filter. This was one of the most inexpensive filters we found in the Dominican Republic, and will be able to easily exchange with in the system. This filter was chosen after discussion of what would work best within our system, and the pros and cons of different filter systems. The filter was then attached with P.V.C. adaptor fittings and attached the filter to the wall to prevent theft and weather security issues. | We also used an activated carbon with silver filter. This was one of the most inexpensive filters we found in the Dominican Republic, and will be able to easily exchange with in the system. This filter was chosen after discussion of what would work best within our system, and the pros and cons of different filter systems. The filter was then attached with P.V.C. adaptor fittings and attached the filter to the wall to prevent theft and weather security issues. | ||
====Excel==== | ====Excel==== | ||
Revision as of 13:26, 8 July 2011
Background
The Humboldt State University Dominicana Summer 2011 Program is working with the neighborhood of La Yuca in the Dominican Republic. Within Dominican Republic, tap water is not potable, and thus families must find some way to receive potable water. Within this program, we strove to design and build a solution to this issue along side the members of the community in order to learn together and create a bond with the neighborhood. One of the reasons the Dominican Republic is an optimal place for rainwater catchment is the quantity rainfall received each year within the country. As seen below, every month receives at least a small amount of rain. For example, even within March, which receives the least amount of rain, 2.1 inches of rain, will accumulate quickly to several gallons on a moderate size rooftop.
The Team
Our team consisted of community members, UNIBE members, Humboldt State University members, and RevArt members. Lauren Adabie is a second year student at Humboldt State University studying Environmental Engineering and Chemistry degrees. Omar Abi-Chahine is a Environmental Science major at Humboldt State University. Freddy Mendoza is studying Architecture at Universidad Iberoamericana. Ana Elisa Mejia Boo is an Architecture student at Universidad Iberoamericana.
Rainfall in Santo Domingo
| Month | Total Rainfall Average(in) |
|---|---|
| January | 2.5 |
| February | 2.2 |
| March | 2.1 |
| April | 2.8 |
| May | 7.4 |
| June | 5.5 |
| July | 5.7 |
| August | 7.0 |
| September | 7.1 |
| October | 7.4 |
| November | 3.9 |
| December | 3.3 |
source: Weather Channel [1]
Problem
The project goal is to provide a sustainable alternative to other methods of receiving potable water by building a scalable and replicable rainwater catchment system.
Criteria and Constraints
The Criteria and Constraints below were developed from discussion with the Community and the necessities to build and complete a successful project.
| Criteria | Weight | Constraints |
|---|---|---|
| Safety | 8.5 | Must be safe for children and others to be around |
| Cost | 8.5 | Buy Back Time within 2 years and Cost, Cheap |
| Ability to be Reproduced | 7.5 | Materials Need To Be Local and Built with Community |
| Educational Value | 7 | Teach the Community About Rainwater Catchment |
| Potability | 10 | Must meet standards for water consumption |
| Durability | 8 | Must last a long time and withstand hurricanes and other natural disasters |
| Gravity Fed | 7.5 | Should not need pumps. Gravity should draw the water through the filters. |
Site
After considering different sites, we chose the site that cost the least and that we believed would work well. The site used, as seen to the right, involved four stories and two different buildings. Although using two different buildings caused a few problems during construction, it was ideal for the construction of the system.
Final Design
Our final design created a potable rainwater catchment system for a community that we believed best met the criteria, and worked with the site well. The system catches rain on a fourth story roof, and channels the water through three inch p.v.c. from the roof to the second story of a separate building. After the second story While at this time there is not a lot of storage, more storage can easily be added to retain more rainwater.
Rooftop
The roof used for the rainwater catchment sat on top of four stories of houses.
First Flush
For the first flush, we used volumetric first flush. Volumetric first flushes calculate a specified volume that is considered dirty water, due to roof contamination between rains, and captures this volume of water before allowing the rainwater to be captured for consumption. After calculations, which can be found at First flush, our first flush required 40 gallons. Due to this calculation, we constructed our first flush using a 40 gallon drum, p.v.c. adaptors and a 4" ball.
Tinaco
After the first flush fills, the water enters the tinaco. A tinaco is a water storage tank use within the Dominican Republic due to water shortages and power outages. When the power is out within a house, the house does not have municipal water, due to this, many house have tinacos on the roofs to provide water with pressure. After much searching, we were able to find a cheap tinaco within Villa Consuelo, a district within Santo Domingo.
Filters
Due to the community desire for the rainwater to become potable, filters were required. After research and considerations, we chose to use a slow sand filter and a activated carbon with silver filter. We chose the filters by considering what was required of the water, as well as the cost of the filter and local materials use in the filter. Our slow sand filter was then placed on a 5 ft metal brace and attached to the wall to prevent theft and hurricane issues. Below the slow sand filter, our final filter, an activated carbon and silver filter, was connected and attached to the wall. This filter occurs just before the spigot, where the community is able to collect water.
Slow Sand
Our team chose a slow sand filter due to its ability to remove bacteria, heavy metals and small particulates. In order to construct the slow sand filter we bought a 55 gallon drum, sand and gravel. First we drilled three holes in the food-grade plastic 55 gallon drum, two on the bottom of the drum, and one on the top of the drum. Then using three male-female compression fittings, we created an entrance and exit for the water, and a valve for back flushing the slow sand filter. Back flushing is necessary due to the growth of bacteria and algae within the slow sand filter. After securing the male-female compression fittings, we filled the drum first with gravel, then with sand. The part of the filter which consist of gravel is much smaller than the sand, and we filled the gravel to a little bit over the adapters. After we began filling the drum with sand. Due to the need to raise the filter 4 feet onto a bracing system, at first we only poured in a small amount of sand. We were then able to use a pulley system to place the filter on the metal brace.
Activated Carbon with Silver
We also used an activated carbon with silver filter. This was one of the most inexpensive filters we found in the Dominican Republic, and will be able to easily exchange with in the system. This filter was chosen after discussion of what would work best within our system, and the pros and cons of different filter systems. The filter was then attached with P.V.C. adaptor fittings and attached the filter to the wall to prevent theft and weather security issues.
Excel
Excel played an integral part within the construction of our rainwater catchment system. After much hardwork, an excel book was created that can be adapted for other rainwater catchment projects. This book was based off the Basic rainwater collection calculations, taking the included excel and adding several sheets for cost, filter types, pipe sizing, first flush, and buy back time.
Cost
This is a rough estimate. http://dl.dropbox.com/u/14930656/rainwatercalcs.xls