Ecuador Dispatches, Jan/Feb 2001
(Rio Chone Border From Astillero to Kilometro Ocho —
Excepting El Toro Watershed)
January 23, 2001
By Peter Berg
The area of Bahia de Caraquez that borders Rio Chone from
Astillero to Kilometro Ocho is backed by a long series of eroded hillsides
that drain into the river and bay. The principal erosion was initiated by
deforestation and grazing over decades, but recently made massive by El
Nino mud slides and an earthquake in 1998. This report addresses the
suitability of using only plantings with native species of grasses, bushes
and trees to assist in controlling future erosion and fulfill other
purposes.
A model for this type of revegetation in the area exists
in Maria Auxiliadora barrio where mud slides destroyed a dozen houses and
killed sixteen people. Exclusively native plants have been used there to
assist in erosion control, provide an urban corridor for the endemic
neotropical dry coastal forest, and create an urban park with stairways
and paths named "El Bosque en Medio de La Ruinas" (The Forest in
the Ruins).
The focus of this report is the portion of eroded land
that is remedial using only plantings without physical alteration of
landscapes such as terracing or removing tops and sides of hill. Although
this represents only about one-half of the total eroded area, it is the
author's opinion that the remainder will be unduly expensive to undertake
while failing to ultimately provide the land stability that would be
intended. Because of the lack of structural geological elements in the
subsoil, terracing can actually lead to greater future erosion. Removing
tops and sides of hills will alter water drainages in ways that could
prove disastrous.
The watershed of El Toro creek has been excepted from this
report because it covers an extensive area inland from the border of Rio
Chone. This is an important feature of the whole area but deserves its own
survey and revegetation program even though it ultimately funneled into
part of the same region covered by this report.
The following survey was accomplished in two field trips,
one in September 2000 and the second in January 2001. Peter Berg, Director
of Planet Drum Foundation, and Ivan Aguirre of Bahia de Caraquez
Department of Public Works made estimations using a truck that followed
the main highway and sometimes drove on side roads. (For this reason, the
survey may underestimate the geographical area involved by as much as
thirty per cent [30%] which might have been visible on foot.)
Stations of Observation and Land Area Estimates
Estimates of land areas were made from the following
points of observation.
A) Calle 3 Noviembre
Behind and above Armada building (actually north slope of
La Cruz). Nearly perpendicular area about sixty meters wide consisting of
one hectare. Not treatable.
At Eugeno Santos Street. Nearly perpendicular area about
one hundred meters wide consisting of one and a half hectares. Not
treatable.
South of street with a pump station on the corner to the
curve in the road. About two hundred meters consisting of 4-5
hectares. Treatable.
South of the next street. About one and a half hectares.
Crest difficult but everything below is treatable.
South of Elasco Ibarra Street. About twenty to
twenty-five meters wide consisting of one hectare. Upper is treatable
but lower is not.
East halfway to street that leads to Evangelistic Church.
About 2 hectares. Lower is possible to just below top.
South of unnamed street to Evangelical Church. About 3
hectares. Lower is possible but because upper is not it would be in
jeopardy.
South of Rudolfo Cedeno Street. About one hectare below
ceibo tree on ridge. Did not slide and does not need treatment.
East to primary highway in direction of Leonidas Plaza.
About 5-7 hectares. Not treatable.
B) Exit Calle 3 Noviembre
East from speed bump in primary road to Leonidas Plaza.
About 7-10 hectares. Did not slide much and doesn't require much
treatment.
C) Leonidas Plaza
South of Velasco Ibarra Street. About 6 hectares.
Treatable except extreme top of the hill. (Observation point to see about
half of area previously described from top view looking down an back to La
Cruz.)
West corner of cemetery road. About 6-8 hectares.
Treatable.
East to border of El Toro Creek. About 25-30 hectares.
Treatable.
D) Fanca
West border of Fanca Creek (beyond El Toro). Bowl-shaped
area of about 5-7 hectares. Treatable in 3-4 hectares.
Behind Fanca II settlement. About 15-20 hectares.
Treatable in 5 hectares; some intact vegetation.
North of Fanca I and Fanca II settlements. About 15-20
hectares. Treatable in 5 hectares; some severe damage.
E) Kilometro 5 1/2 to 8
Km 5 1/2. About 10-15 hectares. Not treatable.
Km 6. About 7 hectares. Treatable in 2 hectares.
Km 6 1/2 (Saiananda). About 6 hectares. Treatable in 2
hectares.
Km 7. About 6-8 hectares. Not treatable.
Km 7 1/2. About 6 hectares. Treatable.
Km 8. About 12-15 hectares. Treatable.
North toward Rio Chone from highway. About 20-25
hectares. Treatable in most part; 2 hectares not treatable.
Estimation of Total Land Area and Amount Treatable
Through Plantings Alone
