Ecological Restoration in Montrei

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Understanding the importance of its wetlands and wild areas, Montrei began a program of restoration of key natural areas within its territory beginning in the 1980's. Many of the areas under the project have been damaged through use and mismanagement, others for commercial uses.

This program has been highly controversial in Montrei. Some believe that it is ethically wrong to move people from land they have lived for generations, but officials say they are planning housing developments near the reclaimed land, as well as giving equal compensation for the land taken. Others say that it reduces the amount of agricultural land that Montrei may need, but officials cite the fact that in most of these areas, such land is being sold by their owners to housing developers at exorbitant prices, and there is development in places like the upper Val de Cañias for agricultural purposes.

Montrei Wetlands

Montrei has several major current and historic wetlands. Historically, the wetlands throughout Montrei were seen as useless places full of mosquitos, and in the interior, Malaria. The wetlands were in fact highly important feeding grounds along the west coast migratory corridor. It is this view of the worthlessness which prompted Alta California to agree to giving Montrei the amount of land it gave, as Alta California failed to see the richness of the land and thought it was a small price to pay.

Most of the coastal estuaries were formed from former coastal valleys and river channels. The Baîa de San Francisco was formerly a low lying coastal valley during the ice ages (due to uplift of coastal mountains during the subduction phase several million years ago), and near the capital of Montrei, the Rio de Cañias and the Rio de Paxaros flowed into a single mouth. With the rise of the sea as the ice ages ended, all land below the curent sea level filled with salt water, forming extensive low lying brackish marshes. The brackish water in these marshes are utilized as spawning grounds, and of course, feeding grounds for the many birds that live in the area year round, or visit during annual migrations. The number of birds which used to use these wetlands was often described as incredible to see, especially when the great flocks took wing.

However, during the last century, many of these areas were drained, or otherwise altered for some purpose. Near Montrei, the Gran Estairo had previously opened into the Rio de Cañias, which flowed a mile or so further north before emptying into the Baîa de Montrei. At the turn of the century, an attempt was made to open the mouth to the sea where it met the Rio de Cañias in order to create a second harbor. The river was then opened a few miles south, and the old channel was closed with a dyke. However, littoral drift of sand often closed off the new mouth of the estuary, and in wet winters, the river often pushed through the dyke and flowed into its old channel. In the Baîa de San Francisco, many of the marshes were turned into salt pans for a salt producer, or were filled with dredge spoil from the bay bottom to create flat land for building. The city of Las Cañias also filled in most of the lakes forming a chain along the Val de Cañias to provide farmland, however, in wet winters, the lakes would re-fill and the land above would flood, or turn swampy again.

Projects and Future Proposals

There are three major projects underway:

  • Restoration of the Gran Estairo, and Rio de Cañias near the Baîa de Montrei.
  • Conversion of farmland over the former lakes and marshes of the lower Val de Cañias.
  • Restoration of the salt pans along the southern end of the Baîa de San Francisco to marshland.

The following are proposals:

  • Baîa de Tomales, and Estairo de Drake
  • Laguna de Bolinas
  • Joint restoration of the Sacramento delta by Montrei and Alta California

Gran Estairo and lower Rio de Cañias

By 1985, this are had been significantly changed from its pre 1875 form. The changes began soon after Paul Lavere and Cato Vierra decided to turn the almost failed city of St. Paul (now called Lavere) into a secondary port on the Bay of Montrei.

The first major change was diversion of the mouth of the Rio de Cañias south, just north of the Rincon de las Cañias at the turn of the century. Both ends of the river just south of Estairo de Moro Coxo, and at the bend in the river where it headed north were dyked off to prevent the river from running back south and to prevent tides from moving down the old river bed. With the river shunted into the bay well to the south, Estairo Grande turned from slightly brackish to almost entirely saline. It was now flushed by the ocean.

The second major change was the opening of the dunes directly in front of the mouth of Estairo Grande where it joined the lower end of the Rio de Cañias. This was done to make it easier to enter and leave the Estairo. The old mouth of the river several miles north quickly began to close off due to sand. By 1985 the old mouth was effectively hidden by dunes slightly lower than the surrounding dunes. This mouth had to be kept open by near constant dredging due to natural littoral drift of sand. The opening of the dunes directly in front of the mouth of Gran Estairo had the effect of increasing tidal scour, and speed of flow as tides in the ocean changed from high to low.

Due to increasing erosion due to tidal scour, this was the first proposed project. Conservationists proposed this as the first project due to the steadily widening channel of the slough, and the fact that the current ecosystem is not natural to it, that it is entirely influenced by man. They also pointed out that the channel could widen to the point where it began to erode the surrounding hills, despite extensive Salicornia cover of the mudflats. Approval was also given in part due to the failure of the harbor at Lavere, most fishermen had moved to the capital south of Lavere to take advantage of opportunities found there after the Montrei harbor was modernized in the late 1970's, and the harbor had been host to just a few fishing vessels, none of them commercial.

The first step began with dismantling of the run-down harbor. Money from the project was used to buy land along the old river bed to the south, and to convince people to move from areas which were to be converted back. After the old harbor was removed, the old channel of the Rio de Cañias was trenched to remove soil which had been used to narrow it. Then, the two dykes at both ends were removed, first the one close to Gran Estairo, and then the second along the Rio de Cañias. Sand from the bay was used to fill in the mouth, and to help the river to turn northward and flow into its old channel. This work was completed between Spring and Fall, to avoid sudden flooding during winter.

The second step was the opening of the original old mouth. This was opened first to prevent back flooding up the Gran Estairo by the river. As the old mouth was opened, the river still flowed out of the mouth in front of the mouth of the Gran Estairo.

After the new mouth was completed, the mouth that opened in front of the mouth of Gran Estairo was then blocked off to stop direct tidal influence. This now changed the Gran Estairo into an estuary directly influenced by the Rio de Cañias rather than the sea. It was not long before salinity of the Gran Estairo dropped to fresh or slightly brackish as the river pulled saline water out of the estairo.

As salinity dropped, patches of Salicornia, a halophyte began to dissappear from the upper estuary being replaced by willows and cottonwoods resembling old descriptions of the area. Patches of tule and cattails also started to appear, and displaced the patches of Salicornia, which remained only in the most brackish areas in which more agressive freshwater species would not grow.

Estairo de Moro Coxo was also greatly affected. When the changes were still in place, it was also tidally influenced as it too was cut off from a supply of fresh water. However, when the new changes took effect, it returned to being entirely freshwater, and freshwater riparian species again began to colonize its banks, turning it back into a freshwater marsh.

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