Students from the Students in Free Enterprise (SIFE) program from Drury University, Missouri, USA; have partnered with Edward Jones - a financial advising firm in the United States which paid for the materials and the transportation of volunteers to the island; to undertake this project; which will serve to benefit the Holy Cross School.
SIFE is an international non-profit organization that works with leaders in business and higher education to mobilize university students to make a difference while developing the skills to become socially responsible business leaders.
The project, the "Floating Rain Garden" system is scheduled to be completed within 6 days and promises to save Holy Cross in around $12,000.00 per year. Presently, the water used by the school drains into a system which separates the solid waste from the liquid waste. The liquid waste seeps into the earth, and eventually forms part of the ground water. This in itself poses health issues for residents living in the area. The Rain Garden system will eradicate this problem.
The system would consist of the construction of a 20*20*4 feet structure containing a pond; using wood posts and planks with the posts sitting on the limestone bedrock. Cables would provide additional support. The design includes a small amount of sand and gravel which would serve as a final filter for reclaiming the water.
This will be followed by placing a floating water hyacinth plants on the water surface. As the plants grow, their roots extend into the pond and serve as a nutrients remover. The system would be divided into four watertight sections.
The waste water enters the system by flowing into the first section of the system, which will contain a dual head air diffuser. Air will be pumped into the diffuser using a windmill with an electric back up pump. The first section will be the most active of all four sections. Fine suspended solids would enter the section with the liquid waste. Bacteria supported by the aeration would digest the solids and consume or release most of the ammonia from the liquids.
The water will be decanted as it flows through the four sections. The end portion of Section 4 will have a wet well with a PVC pipe collection system, covered with sand and gravel which would serve to further filter the reclaimed water before it is pumped back to be reused.
The water plants used in the floating containers can be trimmed or cut back on a regular basis to stimulate further growth; and be later harvested and used as compost to produce garden soil.
The water coming out of this system will be purified - not to the point where it is drinkable - but
can be used for flushing. San Pedro Sun