The garden on the west side of campus is integral to beautifying the college and is also important in promoting green infrastructure throughout the student body.  Currently, the garden is watered by tap water – an unneeded expense and waste of resources as underneath the athletic fields are detention tanks that hold rainwater.  These untapped sources can be used to reduce the cost of running a community garden and can also introduce more green structures into our campus’ infrastructure.  Our proposal is to install solar panels near the athletic field that would power a pump, allowing water to move out of the tanks into a smaller tank near the garden.  Introducing this kind of structure will not only provide a local benefit to this area of campus, but can also act as a model for various other sides of campus where tap water is used instead of rain water. For example the sprinkler system could in the foreseeable future also benefit from this transition to rain water.
An example of the system by which water is pumped into a tank by a solar panel

The tapwater currently used for watering the garden, can be used in other ways – such as filtered for drinking water.  This kind of system will also lessen the strain on New York City’s sewer systems, something that is important for the community at large.  Instead of using an electric pump, we decided to use a solar paneled pump because it is an alternate, cheaper, more efficient form of energy. Our plan involves placing the solar panel elevated of the ground near the garden and the only costly point throughout this process would be initial cost of buying a pump. We have also designed an irrigation system that will lessen the amount of pressure needed and will effectively water the entire garden. It is essentially a system of perforated rubber and PVC tubes spread throughout the garden that would disperse water evenly and efficiently without requiring a large amount of water pressure. Although this is a small improvement, it will serve as a model for other areas on campus and will help students recognize the need for alternate energy sources in our community.

We identified the garden as a potential beneficiary of harvested rainwater. Currently water harvested from around the athletic field is held in detention tanks placed under the athletic field. Our proposal with this area is to install solar panels near the athletic field, that are elevated six feet of the ground, that would power a pump that would move water from the detention tanks to a smaller tank near the garden for irrigation purposes.

The major structures that we would need to introduce for this particular idea would be: solar panels, pipes leading from the detention tanks to the garden and a method to store and disperse water through irrigation.

The type of irrigation system that we are considering using is a drip irrigation system. It does not require much water pressure and is essentially a series of tubes or pipes with holes in them spread out into the plots of land in the garden. They water plants by providing slow streams and drips of water. The specifics of the system, such as the type of irrigation emitter and flow rate are variable and dependent on the type of garden and caretakers choice. The water for this system will hopefully come from a roughly 200 gallon storage tank or barrel that would be filled with harvested rainwater from the detention tanks. The tank would be continually filled with water by a pump until full and would be placed near the garden, preferably at some height of the ground to create water pressure.

Calculations:

This calculation was made by taking the amount of work necessary to move the water and dividing by the wattage supplied by one panel. Speed is not of great importance since 200 gallons is more than enough for the garden and after the initial transfer of water, the pump should always maintain a full tank when irrigation is unnecessary. However, the pump has some setbacks as the purchase and installation of it would be costly.

Function, Benefits and Potential Problems:

There are a plethora of benefits of utilizing rainwater for irrigation. First off, the rainwater would not be wasted by being drained into the sewer, therefore reducing the expenses for water treatment in sewer systems. The fresh groundwater can be used more efficiently for other purposes, such as being filtered for drinking water. The rainwater would reduce expenses of using other water sources, as we would have a constant supply of water from our storage tank.

The solar panels can be useful for transporting rain water to the water storage for irrigation. They would provide an alternative and more efficient source of energy.