Water and Agriculture Team:

Water and Agriculture Team: Montaña de Luz 2010 Members: Peter Dobler Francis Krivanka Chris Ratcliff Kevin Kuhn

Overview • Four main projects: • Water Filtration • Compost • Garden • Tilapia Pond

Water Filtration • Previously installed by an earlier group, but was currently disconnected due to a low flow rate out of the system because of the lack of replacement cartridges • Other options were researched, but the current system was determined to be the best • MdLkitchen highest priority over director’s house-Vicki • New version of cartridges

Communication! • Main problems with previous projects lack of effective communication with MdLstafffocus on this • -Vicki: current staff will sustain projects • Make sure Vicki understands what is going on • Meetings with staff at beginning and end of week • Placed the instructions for replacing the filters in • the correct order behind the system • Placed the team documentation in • English and Spanish on the wall as well, • contains appearance, function, cost of • filters as well as ordering instructions

Water Testing • Water tested with arsenic kit donated from Hach • Unfiltered water: 30-40 ppb • Filtered water: about 5 ppb • WHO standard: 10 ppb • new cartridges work!! • Chlorine also tested with photometer • Chlorine concentration is still at an adequate level, so no problems there

Future Recommendations • Make sure the filtration system is being sustained, and that Saul is replacing and installing the filters correctly • Improve on some of the past water team’s projects-gravity feed system, irrigation, septic system • Water-related issues with tilapia pond • More effective communication method between OSU and MdL so that redundant/unnecessary projects don’t happen, OSU group is familiar with what MdL is doing, max benefit for MdL

Garden • Goal: Improve Agriculture at MdL • Food • Income • Problem: Weather • Extreme heat • Hard rain • Solution: Protect the plants • Roof already in progress • Shade netting addition

Shade netting addition • Already in progress

Future Recommendations • Assessment • How well is the shade roof working? • How well is the shade roof holding up? • Put up more shade netting to cover the rest of the garden or more areas if necessary

Compost • Goal: develop a good system for composting • Wet vs. dry, greens vs. browns, oxygen • Problem: MdL’s compost area was too full and appeared to be only wet waste • Our solution: • Share proper composting techniques with staff • Utilize more bins for composting • Fill new bins with proper mix of waste

Our Solution

Better Solution • Biodigester • Converts organic waste into biogas and nutrient rich liquid fertilizer, or what could commonly be referred to as compost

Future Recommendations • Biodigester • Talk to Dr. Jay Martin from the Dept. of FABE • Figure out what needs to be done in order to maximize production of both gas and compost • Complete installation • Develop clear yet comprehensive notes for sustainability

Tilapia Culture Goal: Determine feasibility and provide recommendations on operation and management of tilapia culture at Montaña de Luz • Tilapia pond benefits • Sustainable – locally available inputs • Nutrition • Economic value • Integration with chickens/garden • Tilapia pond potential issues • Pond placement/Construction • Oxygen content/Water quality • Feeding • Operating costs Tilapia culture is found throughout the world because it can turn unproductive land into a source of income and nutrition. Can it work for MDL?

Existing Pond • Active for 6 months • 7 fish/m2 (about 300 fish) • 95% of fish sterile • Design Issues • Unnecessary depth • High cost to aerate • Small Surface Area • Limited population • Not enough fish – project was not cost effective

13.6m 8.3m 12.6m 15.6m Pond Construction • For tilapia culture to be successful at MDL, new ponds must be built • There is space next to the chicken coop • Close to the garden • Space for one pond of about 130 m2(or multiple ponds) • 1m depth • More smaller harvests or fewer big harvests? • Must use concrete • Drain required – should be connected to garden Problem - Large initial cost

Water Quality • Tilapias are hardy fish • Dissolved oxygen is the major concern • Tilapia can survive at relatively low oxygen levels • A shallow pond incorporates oxygen through contact with air • Algae photosynthesize during the day creating O2 • At night, algae respire and useoxygen • Algae content must be closely monitored and night time aerators must be used • 10% of pond water should be replaced every week A technique to measure algae content in the pond.* *Bocek, Alex. An introduction to aquaculture. http://www.ag.auburn.edu/fish/international//publications.htm

Feeding Could be the most expensive part of upkeep • Tilapia will eat a wide variety of food • Additional sources: • Chicken/garden/meal scraps • Algae - algae growth in the pond can be stimulated by addition of compost or manure • Possibility for sustainability • There may be a tradeoff between cost and growth rate • Concentrate costs 500 Lempira for a 6 pound bag – Can get very expensive Tilapia eat naturally occurring organisms in the pond which can be stimulated by addition of manure or chemical fertilizers Bocek, Alex. An introduction to aquaculture. http://www.ag.auburn.edu/fish/international//publications.htm

Cost Analysis • Cost analysis based on information received from Universidad Zamorano • Fish @ 27 L/lb • Stocking fry: 85 centimos/fish • Electricity: 18 cents/hr (180 Watt pump for 4 hours a day) • Food: 500 L/6lb Looks promising. Note, however, how much it changes if 1 full bag of feed is needed per week instead of ½ bag.

Recommendations • Use old pond for test • If things go well, build 2 or 3 small concrete ponds next to the chicken coop • Connect ponds to garden to make use of waste water • Carefully monitor algae growth • If not enough, add chicken manure • Experiment with different types of feed to try to minimize costs • Try using scraps from chicken processing • Determine change in growth rate, if any

The End

Water and Agriculture Team: