What is a watershed? Why do they matter in Maui County?

You live in a watershed, even though you might not know it. A watershed is an area of land that drains all the streams and rainfall to a single body of water, such as a river, lake, or ocean. Watersheds and their management are incredibly important for coral reefs because they are the source of fresh water and nutrients that can actually promote reef growth.

Unfortunately, human activities, such as poorly planned development, have caused pollution to enter our watersheds and flow down into the ocean, affecting our reefs. Excessive use of fertilizers, pesticides, and herbicides that are used in farming or lawn care is one source of polluted runoff, also known as nonpoint source or NPS pollution. Urbanization adds to NPS pollution as roads, parking lots, and other developments produce runoff polluted with oil, grease, and other chemicals.  Impermeable surfaces such as paved areas, roofs, and even compacted bare soil increase the rate at which water flows down through a watershed.

Groundwater is also an often overlooked part of a watershed system.  Maui County is currently struggling with coral reef and water quality degradation caused by failed and poorly planned sewage disposal systems that are contaminating groundwater. Like surface water, the direction of flow is towards the ocean, so pollutants that are pumped into injection wells do eventually have an impact on our coastal environment.

Fortunately, there are a number of steps that anyone can take to help protect their watersheds. Here are ten things you can do:

1. Reduce the use of household chemicals and pesticides that can pollute watersheds – many of these common pollutants contain harmful elements that negatively impact coral reefs.

2. Conserve water by taking shorter showers, turning off the tap when brushing your teeth and only running full loads in the washing machine. This will help reduce water waste and also help to prevent runoff from carrying pollutants into our watersheds, especially through groundwater.

3. Dispose of waste properly by making sure all hazardous materials – and this includes any unused medications – are taken to a designated drop-off center, not put down any drains or flushed down the toilet.

4. Participate in beach cleanups or other local events dedicated to protecting our waterside ecosystems – this will not only remind us how important watersheds are but also help keep them clean.

5. Plant native vegetation. The plants that grow naturally in a given area are adapted to the local conditions and provide essential food, shelter, and refuge for wildlife. Any vegetation helps filter polluted runoff before it enters our water, but by reducing water consumption.

6. Avoid dissolving detergent products – both pods and sheets – these products are actually packaged in a dissolving plastic that breaks down into microparticles in water. Even though not visible to the naked eye, these particles are not fully rinsed from clothing and cannot be filtered out by the municipal wastewater treatment systems we have in Hawai’i.

7. Avoid using or disposing of single-use plastics or Styrofoam products near rivers, streams, lakes, or oceans. Even though Maui County has banned some of these single-use materials, they still exist in packing materials.  If not recycled, and most are not, these materials break down into small pieces that can be ingested by animals, including reef corals.

8. Reduce pesticide and herbicide use, as these chemicals have been proven to contaminate our water and harm coral reefs. Use organic gardening products when possible, and follow any local ordinances pertaining to the proper disposal of hazardous materials.

9. Volunteer with a local watershed organization or join a cleanup effort near where you are located. Community members can help make an impact by simply picking up trash on shorelines or in waterways; this not only reduces debris but also helps protect aquatic life from toxins and pollutants that may be present in the garbage being collected.

10. Help spread awareness about how watersheds are connected to coral reefs, and the pollution that can be caused by human activities. The more people know about this issue, the more likely it is for us to make a collective effort toward protecting our watersheds and ultimately, our reefs.

Even if you do any one of the tips above, you will reduce your impact on watersheds and help protect our coral reefs. Watershed degradation and the resulting pollution are one of the top three things harming our coral reefs.  Together, let’s keep our waters clean, safe and healthy so that future generations can enjoy the beauty of coral reefs.

Maui has three watershed partnerships that are great resources for information about watersheds and provide opportunities for you to get involved in watershed conservation and management.

East Maui Watershed Partnership

West Maui Mountains Watershed Partnership

Leeward Haleakala Watershed Restoration Partnership