Carving up the Rio Tigre with Heavy Equipment
Destroying One of the Largest Watersheds on the Osa
Yesterday the town of Dos Brazos had confirmation that basically the whole river from the bridge on the main road up to the border of the Reserva Golfo Dulce just outside of Dos Brazos was all in danger of being mined for gravel and rock. Members of the Association of Puerto Jimenez, who came to a meeting in Dos Brazos by invitation, confirmed that not only the town of Puerto Jimenez but 4 other companies were working on getting concessions along the Rio Tigre. One concession, we believe is already been granted, making a total of 6 concessions each with a possibility of 2km of river to work in.
These concessions are for mining directly in the river course, using heavy equipment to extract gravel and rock for commercial use. It will involve channeling the river or making roads on either side as has been demonstrated by the very visible mining going on near the bridge on the main road. This will destroy one of the biggest rivers on the Peninsula. A river is a whole unit, what goes on downriver effecting upriver and what goes on up river effecting down river. Not only will this cause a lot of erosion (the river always needs to replace the gravel taking it from up stream and from the sides of the river) but it will change the water temperature and flow of the river effecting the fish and shrimp spawning. The shrimp or crayfish living upstream are the main food source of the river otters. They need to swim down to the gulf to reproduce in brackish water and many fish in the gulf need to come into the rivers or mangrove areas to reproduce. There will be more silt in the mangrove areas and on the slowly recovering reef that was destroyed by the gold mining. There will be hydraulic leaks and line breakage, contaminating the watershed with harmful chemicals.
We have lived on this river for many years and learned a lot about how rivers work. Rivers are extremely fragile, complicated and difficult to understand. They are an important part of the whole forest and ocean ecosystem.
Right now our river has been filled in by sand possibly due to the excessive amounts of gravel being taken out for the road project. The river is desperately trying to replace what was lost downstream. There are almost no rocks exposed for fish fry to attach to or for shrimp to hide under during the day. It is moving with less turbulence increasing the temperature as well. There have been many studies done in Northern California on the effects of mining gravel in river channels. Apparently that was cited as one of the main causes of the salmon industries collapse many years ago. If anyone would like, I have copies somewhere of one or two of the studies
Not only will the ecology of the river be destroyed but the lives of the inhabitants both human and wildlife will be effected as well by these proposed concessions. All the citizens of the Osa need to pay attention and make sure that development does not destroy the peninsula we treasure.
Liz Jones
Bosque del Rio Tigre
