Dunedin Engineer: Strategic Planning Should Be High Priority for Caye Caulker
Written by Bob Brotherton, www.brothertonengineering.com
Friday, 05 January 2007 www.brothertonengineering.com
As land develops on an island, several things happen to interrupt the normal cycle of water percolating into the soil. First is that rooftop and road drainage begin to reduce the surface area that normally perks water into the soil and this water runs off the land into the ocean where it is lost to the infiltration cycle. Even dirt roads that get hard packed will run this water off and not allow it to perk at the original rate of the old soil that is naturally there. Another issue is that as you mention, if the wastewater is not properly treated and recycled, this water eventually contaminates the small amount of clean water in the fresh water lens. To overcome that potential for pollution would require the central collection of that wastewater, proper treatment, and then land application of the Reclaimed Water back to the soil by spray irrigation on local landscaping or larger sprayfields. If the water pumped from the ground has a rotten egg smell, then that is probably hydrogen sulfide which is common in groundwaters like Caye Caulker has.
The history of past water supply considerations on Caye Caulker is very interesting. It is very common that people do not want to pay for a central water system as long as they have water they can pump out of the ground for free. This leads to a very serious problem when everyone's water becomes contaminated by wastewater or seawater intrusion about the same time and then there is crisis. Then they are willing to pay but the time to implement the improvements is too long to give immediate relief. Also, trying to quickly implement improvements leads to bad decisions, poor construction management, and contracts with private companies who hold the upper hand on bidding for work since the area is in a crisis situation. Caye Caulker should not want to put themself into a crisis management position on providing new centralized utilities. Seawater desalination requires a significant amount of power. On Ambergris Caye, the power for their desalination process is supplied by diesel engines that directly drive the pumps required to pressurize the membranes. There is not enough electricity on that island to provide power to run their water system. If Caye Caulker was really wanting to do this right, they need to look at more than just their water and sewer needs. They need to look at their power supply needs too for the long term including providing underground power lines, savings from common trenches for utility installation, and improving roads and drainage to maximize the capture of stormwater runoff into treatment swales for percolation back into the natural groundwater table.
The Master Plan for San Pedro (another but related subject) does not address utility service issues. This was pointed out to them in a (no cost) report that I did for them two years ago. There is a major disconnect between local town, the GOB, and private utility operations in the current type of planning process being done on Ambergris Caye. This is because the utilities have been privatized and therefore the assumption is that all is well. Private utilities operate solely on the concept of profit taking and not investments that tie together with development plans. When there is no good government development planning and zoning, then this further separates the private utility's ability to make investments in new infrastructure due to uncertainties. Good Master Planning ties together land development issues with projected infrastructure needs. If the planning process is done well, the general public in the villages learn about the issues during the planning process and then understand their options and their need to make investments before crisis hits.
Last Updated ( Friday, 05 January 2007 )