TOWARDS AN INTEGRATED MANAGEMENT OF THE LOWER ()

First phase: Controlling the flow and sediment discharge distribution at the bifurcation between the Samaria and Carrizal rivers

Grijalva River - Mexico 1 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist

Grijalva River - Mexico 2 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist INTRODUCTION • The inundations in require an urgent solution • After the 1999 flood event, the authorities decided to: – Construct a weir in the rio Carrizal – Investigate effective (definitive?) solutions to control the inundations • Nonetheless, the scheme should be designed taking into account the potamological context (potamology = science of rivers, more general than fluvial hidraulics)

Grijalva River - Mexico 3 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist GRIJALVA BASINS

Average annual runoff in Mm3

Río Grijalva

36,493.883 36.9% Río Usumacinta 62,206.623 63.1% Total 98,700.506

Basin Río Grijalva

Basin Río Usumacinta Areas in km2 Río/País México Guatemala Total por Ríos Grijalva 52,348.08 5,610.00 57,958.08 Usumacinta 30,627.98 44,373.81 75,001.79 Total por paises 82,976.05 49,983.81 132,959.87 Total de totales

Grijalva River - Mexico 4 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist POTAMOLOGICAL CONTEXT • The Grijalva river has the largest part of its basin in the Sierra Madre and enters its lower reach in the large coastal plain, before discharging in the Golf of Mexico • The last stretch is within an alluvial fan (delta) in which several branches have developed through time by avulsion (change of the river course)

Grijalva River - Mexico 5 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist BARRA DE SAN PEDRO BARRA DE SAN PEDRO BARRA DE SAN PEDRO

BARRA DE FRONTERA BARRA DE FRONTERA BARRA DE FRONTERA

BARRA DE FRONTERA BARRA DE BARRA DE TUPILCO TUPILCO TUPILCO BARRA DE DOS BOCAS BARRA DE DOS BOCAS BARRA DE DOS BOCAS Sta. Ma. de la FRONTERA FRONTERA BARRA DE CHILTEPEC Victoria BARRA DE CHILTEPEC BARRA DE CHILTEPEC

PARAISO PARAISO PARAISO

COMALCALCO COMALCALCO COMALCALCO

Rio G r i j a l v a Rio G r i j a l v a

NACAJUCA Rio G r i j a l v a

JALPA JALPA NACAJUCA JALPA NACAJUCA

CUNDUACAN R i o S e c o R i o S e c o

R i o M e z c a l a p a CUNDUACAN CUNDUACAN CARDENAS Rio de la Sierra VILLAHERMOSA VILLAHERMOSA CARDENAS Rio de la Sierra CARDENAS Rio Carrizal Rio de la Sierra VILLAHERMOSA M e z c a l a p a ( San Juan Bautista ) M e z c a l a p a ( San Juan Bautista ) ( San Juan Bautista )

R i o R i o o Rio Viejo o Rio Viejo HUIMANGUILLO ROMPIDO DE HUIMANGUILLO NUEVA ZELANDIA HUIMANGUILLO

ROMPIDO MANGA DE CLAVO TACOTALPA TACOTALPA Rio Teapa TACOTALPA

Rio Teapa Rio Teapa

Rio Tacotalpa Rio Tacotalpa

TEAPA R i o M e z c a l a p a TEAPA R i o M e z c a l a p a TEAPA PICHUCALCO PICHUCALCO Rio Tacotalpa PICHUCALCO SIGLO XVI ROMPIDO DE NUEVA ZELANDIA - 1675 ROMPIDO MANGA DE CLAVO - 1881

BARRA DE SAN PEDRO BARRA DE SAN PEDRO BARRA DE SAN PEDRO

BARRA DE FRONTERA BARRA DE FRONTERA BARRA DE FRONTERA

BARRA DE BARRA DE BARRA DE TUPILCO TUPILCO TUPILCO BARRA DE DOS BOCAS BARRA DE DOS BOCAS BARRA DE DOS BOCAS FRONTERA FRONTERA FRONTERA BARRA DE CHILTEPEC BARRA DE CHILTEPEC BARRA DE CHILTEPEC

PARAISO Rio Gonzalez PARAISO PARAISO

Rio G r i j a l v a

COMALCALCO COMALCALCO COMALCALCO

Rio G r i j a l v a Rio G r i j a l v a Rio Cuxcuachapa Rio Cuxcuachapa

JALPA NACAJUCA JALPA Rio Jalupa NACAJUCA JALPA NACAJUCA

R i o S e c o R i o S e c o R i o S e c o CUNDUACAN Rio Chilapa Rio Medellin Rio Chilapilla CUNDUACAN CUNDUACAN Rio Cañas Rio Samaria VILLAHERMOSA VILLAHERMOSA Rio Carrizal VILLAHERMOSA Rio Carrizal CARDENAS Rio Carrizal ( San Juan Bautista ) CARDENAS Rio de la Sierra CARDENAS ( San Juan Bautista ) Rio de la Sierra M e z c a l a p a ( San Juan Bautista ) Rio de la Sierra

R i o Rio Viejo o Rio Viejo Rio Viejo

HUIMANGUILLO ROMPIDO DE HUIMANGUILLO HUIMANGUILLO LA PIGUA - 1904 ROMPIDO DE CAÑAS ROMPIDO DEL VELADERO ABIERTO EN 1952 CERRADO EN 1953 TACOTALPA TACOTALPA TACOTALPA

Rio Teapa Rio Teapa Rio Teapa

Rio Tacotalpa Rio Tacotalpa Rio Tacotalpa

R i o M e z c a l a p a TEAPA R i o M e z c a l a p a TEAPA R i o M e z c a l a p a TEAPA PICHUCALCO ROMPIDOPICHUCALCO DE CAÑAS PICHUCALCO ROMPIDO DE LA PIGUA - 1904 1940 ROMPIDO DEL VELADERO - 1952

Grijalva River - Mexico 6 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Summary BARRA DE SAN PEDRO BARRA DE FRONTERA

BARRA DE TUPILCO BARRA DE DOS BOCAS FRONTERA BARRA DE CHILTEPEC

PARAISO

Rio G r i j a l v a

COMALCALCO

Rio Cuxcuachapa

JALPA NACAJUCA

R i o S e c o CUNDUACAN Rio Chilapa Rio Medellin Rio Samaria Rio Chilapilla VILLAHERMOSA CARDENAS Rio Carrizal ( San Juan Bautista ) Rio de la Sierra

Rio Viejo

HUIMANGUILLO ROMPIDO DEL VELADERO ABIERTO EN 1952 CERRADO EN 1953 TACOTALPA

Rio Teapa

Rio Tacotalpa

R i o M e z c a l a p a TEAPA PICHUCALCO

Grijalva River - Mexico 7 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 8 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 9 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 10 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Peñitas

Chicoasén Malpaso

Angostura

Grijalva River - Mexico 11 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA

Profile of the río Grijalva (msnm)

The rio Grijalva runoff, during 500 floods, were much larger before the construction of the dams. In 1963, discharges 400 over 8 000 m3/s were observed at the hydrometric station of Peñitas. 300

200

100

Grijalva River - Mexico 12 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA CAPACITY (In millions cubic meters) 14,000 (For flood regulation) 3,460 (msnm) 500 The was built to regulate the flood events. 400

300

MALPASO (1964) 200 188.0 * 182.5 ** 100 *Maximum extraordinary flood level (NAME)

Grijalva* R* iMaximumver - Mexi coperationo 1 3flood level (NAMO) Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA CAPACITY (In millions cubic meters) 14,000 (For flood regulation) 3,460 (msnm) Discharges reduced with 500 regLual aptrieosna b My athlpea rseos seervoir, nocnoenthsetrleusysó, coopne rlation of spilway was needed in finalidad de regular 400 196la9s, 1a9v7e0n iyd a1s9.73, before MALPASO construction of Angostura.

300

MALPASO (1964) 200 188.0 * 182.5 ** 100 *Maximum extraordinary flood level (NAME)

Grijalva* R* iMaximumver - Mexi coperationo 1 4flood level (NAMO) Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA CAPACITY (In millions cubic meters) 20,000 14,000 (For flood regulation) 8,500 3,460 ANGOSTURA (1975) (msnm) 539.5* 533.0** 500 Is the reservoir with the largest regulation capacity of Mexico. 400 ANGOSTURA

300

MALPASO (1964) 200 188.0 * 182.5 ** 100 *Maximum extraordinary flood level (NAME)

Grijalva* R* iMaximumver - Mexi coperationo 1 5flood level (NAMO) Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA CAPACITY (In millions cubic meters) 20,000 1,680 14,000 (For flood regulation) 8,500 490 3,460 ANGOSTURA (1975) (msnm) 539.5* CHICOASÉN (1980) 533.0** Hydropower scheme with 500 highest potential of 1 500 MW, but with little effect on flow regulation. 395.0* 400 392.5** CHICOASÉN

300

MALPASO (1964) 200 188.0 * 182.5 ** 100 *Maximum extraordinary flood level (NAME)

Grijalva* R* iMaximumver - Mexi coperationo 1 6flood level (NAMO) Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SCHEME OF DAMS ON THE RÍO GRIJALVA CAPACITY (In millions cubic meters) 20,000 1,680 14,000 1,485 (For flood regulation) 8,500 490 3,460 1,091 ANGOSTURA (1975) (msnm) 539.5* CHICOASÉN (1980) 533.0** 500 In December 1967, in the Ostuacan river, between 395.0* Malpaso and Peñitas, was 400 392.5** observed a flood event with PEÑITAS discharge of over 4 000 m3/s. 300

MALPASO (1964) 200 188.0 * 182.5 ** PEÑITAS (1987) 100 *Maximum extraordinary flood level (NAME) 95.5* 87.4** Grijalva* R* iMaximumver - Mexi coperationo 1 7flood level (NAMO) Prof. Ir. J.J. Peters | VUB | Consultant - River specialist IMPACT OF THE DAMS • 4 dams constructed between 1964 and 1987 had a significant impact on the hydrological regimen of the river (Grijalva downstream of Peñitas) • Natural flood events disappeared and the operation of Peñitas dam determines the discharges (little contribution of Platanar river) • A compensation dam foreseen to avoid rapid discharge fluctuation during the day has not yet been constructed

Grijalva River - Mexico 18 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist MGASTOSONTHLY MENSUALES DISCHARGES ENIN P PENITASENITAS 19 1948-199948 - 1999

10,000

9,000 Peñitas Mal Paso Chicoasén Angostura 8,000

7,000

) S

/ 6,000

3

M

(

S 5,000

E

G

R

A H 4,000

GASTOS (M3/S)

C

S I

D 3,000

2,000

1,000

0 Ene-47 Ene-51 Ene-55 Ene-59 Ene-63 Ene-67 Ene-71 Ene-75 Ene-79 Ene-83 Ene-87 Ene-91 Ene-95 Ene-99 DATEFECHAS (MO N(MESES)THS)

MÁXIMO MÍNIMO MEDIO

Grijalva River - Mexico 19 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist GAVENIDASRIJALVA FL DELOOD GRIJALVAEVENTS BE ANTESFORE A NYD DESPUES AFTER CO DENS TCONSTRUIRRUCTION OF PPENITASENITAS DAM

10,000

9,000

8,000

7,000

) S

/ 6,000

3

M

(

S

E 5,000

G

R A

H 4,000

C

S

I D GASTO LIQUIDO (M3/S) 3,000

2,000

1,000 DESPUES DE CONSTRUIR PENITAS

0 1/Sep 11/Sep 21/Sep 1/Oct 11/Oct 21/Oct 31/Oct 10/Nov 20/Nov 30/Nov DATEFECHASS (MON T(D-M)HS)

1951 1952 1955 1956 1959 1963 1987

Grijalva River - Mexico 20 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist HYDROLOGICAL IMPACT

• Change in hydrological regimen, dry and flood seasons in quite constant monthly discharges, except in flood event periods • Between 1987 and 1999, operation of Peñitas dam produced discharge fluctuations during the day between a very low and a very high value (depending on the electricity demand)

Grijalva River - Mexico 21 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist HYDROGRAM 1987, THE YHidrogramaEAR AFTER C OPeñitasNSTRU C1987TION OF PENITAS DAM

6,000

5,500

5,000

4,500

4,000 )

S 3,500

/

3

M (

3,000

S E

G 2,500 R

Gastos (m3/s) A

H 2,000

C

S I

D 1,500

1,000

500

0 03/06/1988 15/07/1988 23/09/1988 26/08/1988 04/11/1988 12/08/1988 02/12/1988 21/10/1988 17/06/1988 29/07/1988 07/10/1988 20/05/1988 09/09/1988 18/11/1988 25/03/1988 16/12/1988 22/04/1988 01/07/1988 15/01/1988 06/05/1988 29/01/1988 08/04/1988 26/02/1988 01/01/1988 12/02/1988 11/03/1988 30/12/1988 Fechas (días) DATES (DAYS) Grijalva River - Mexico 22 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist HYDROGVARIACIONRAM IN OCTO DELBER 1GASTO987, TH ELIQUIDO YEAR AF TENER OCTUBRE CONSTRU CDETIO 1987N OF PENITAS DAM

2,000

1,500

)

S

/

3

M (

1,000

S

E

G

R

A

H C

GASTO LIQUIDO (M3/S)

S I D 500

0

01-Oct02-Oct03-Oct04-Oct05-Oct06-Oct07-Oct08-Oct09-Oct10-Oct11-Oct12-Oct13-Oct14-Oct15-Oct16-Oct17-Oct18-Oct19-Oct20-Oct21-Oct22-Oct23-Oct24-Oct25-Oct26-Oct27-Oct28-Oct29-Oct30-Oct31-Oct DATEDIASS (DAYS)

Gasto Medio Gasto Mínimo Gasto Máximo

Grijalva River - Mexico 23 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SEDIMENTOLOGICAL IMPACT • Sedimentation in the dam reservoirs produce a deficit in sediment supply to the Lower Grijalva

• Only the Platanar river carries sediment to the Mezcalapa river, with large quantities of material from the Chichonal volcano eruption (1982), in total 9 millions cubic meters ashes

Grijalva River - Mexico 24 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist RIVER “RESPONSE” • By sediment déficit, clair water has the tendency to erode the riverbed downstream of Peñitas dam (impact controlled by the nature of the riverbed: rocs)

• The water level gauging station just downstream of the dam hangs today above the waterlevel (was already replaced twice to follow the descent of the riverbed, degradation explained by Lane Balance)

Grijalva River - Mexico 25 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 26 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist RIVER “RESPONSE”

• Products of this erosion move in downstream direction to deposit further, creating many and large sand- and gravel bars in the Mezcalapa

Grijalva River - Mexico 27 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 28 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Río Mezcalapa in Huimanguillo, Puente Solidaridad

Banc protection structures

Braided river

Grijalva River - Mexico 29 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist RIVER “RESPONSE” • A meandering river course would be more adequate to the new hydrological regimen • The strong discharge fluctuation, in the presence of the large sand and gravel bancs, produced between 1987 y 1999 flow deviations towards the banks, • what induced always more erosions, causing a braided riverbed in the lower part of the Mezcalapa

Grijalva River - Mexico 30 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 31 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist BIFURCATION MEZCALAPA • The bifurcation of the Mezcalapa in Samaria and Carrizal rivers exists since 1940, when occurred the Cañas avulsion

• Information is missing on the development of the river between 1940 and 1964, when started construction of the dams

• However, aerial photographs reveal the tendency in the Mezcalapa to amplify its course, although not as much as in the Carrizal river

Grijalva River - Mexico 32 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 33 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 34 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist 1996

Grijalva River - Mexico 35 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Samaria 2000 meandering (canaliform)

Samaria braided

Grijalva River - Mexico 36 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 37 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist BIFURCATION MEZCALAPA • Impact of Samaria bridges: – Produce backwater, with effect on sedimentation when flood retreats – Tendency to outflank by bank erosion • Results in daily fluctuations of discharges (between 1987 y 1999) • Power of the flow distributes in a wide riverbed, reducing the sediment transport capacity

Grijalva River - Mexico 38 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist US DHS-59 for suspended load transport

Grijalva River - Mexico 39 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist US BL-84 for bedload transport

Grijalva River - Mexico 40 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist US BL-84 for bedload transport Operated from a small unit

Grijalva River - Mexico 41 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Delft Bottle BD2 for near-bed load transport Operated from a small unit

Grijalva River - Mexico 42 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Delft Bottle BD1 for suspended load transport Fitting the tail; operated from a small unit

Grijalva River - Mexico 43 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Flow and sediment transport relationship Mezcalapa

Relación gasto sólido (arena y grava) con el gasto líquido Mezcalapa

8,000

7,000

6,000

BL-84 5,000 BD2

4,000 BD1 y = 210.07e0.0025x Expon. (BD1)

3,000 Expon. (BD2) y = 27.973e0.0039x Gasto sólido (m3/día) Expon. (BL-84)

2,000 y = 414.09e0.0015x

1,000

0 0 200 400 600 800 1,000 1,200 1,400 1,600 Gasto líquido (m3/s)

Transporte sólido: BL-84 = por arrastre; Botella de Delft BD2= cerca del fondo; Botella de Delft BD1= suspensión

Grijalva River - Mexico 44 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Flow and sediment transport relationship Mezcalapa

Relación gasto sólido (arena y grava) con el gasto líquido Mezcalapa

20,000

18,000

16,000

14,000 BL-84

12,000 BL-84 + BD2

BL-84 + BD2 + BD1 10,000

0.0025x Expon. (BL-84 + BD2 y = 512.38e + BD1) 8,000 Expon. (BL-84 + BD2)

Expon. (BL-84) 6,000 BD1 y = 574.08e0.002x Gasto sólido (cumulativo, m3/día) 4,000 BD2 2,000

84 y = 414.09e0.0015x 0 0 200 400 600 800 1,000 1,200 1,400 1,600 Gasto líquido (m3/s)

Grijalva River - Mexico 45 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Relationship flow - sediment discharges

Relación gasto sólido (arena y grava) con el gasto líquido Mezcalapa Relación gasto sólido (arena y grava) con el gasto líquido Mezcalapa 20,000 20,000

18,000 18,000

16,000 16,000

14,000 14,000 BL-84 BL-84 12,000 BD2 12,000 BL-84 + BD2

BD1 BL-84 + BD2 + BD1 10,000 10,000

Expon. (BD1) 0.0025x Expon. (BL-84 + BD2 y = 512.38e + BD1) 8,000 8,000 Expon. (BD2) Expon. (BL-84 + BD2)

Gasto sólido (m3/día) Expon. (BL-84) 6,000 Expon. (BL-84) 6,000 BD1 y = 574.08e0.002x Gasto sólido (cumulativo, m3/día) 4,000 4,000 BD2 2,000 y = 210.07e0.0025x 2,000 0.0015x 84 0.0015x y = 27.973e0.0039xy = 414.09e y = 414.09e 0 0 0 200 400 600 800 1,000 1,200 1,400 1,600 0 200 400 600 800 1,000 1,200 1,400 1,600 Gasto líquido (m3/s) Gasto líquido (m3/s) • At low discharges, bottom transport is significant but increases slowly with discharge • Transport close to the bottom increases more rapidly, because of the increase in turbulence • Transport in suspensión, very low at mild discharges, augments more rapidly with discharges than transport close to the bottom

Grijalva River - Mexico 46 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist THE WEIR

• The studies of the weir (numerical and scale models) did not properly contemplate “sediment” • The weir induced formation of an ample sand bar in the centre of the river, upstream • The result has been outflanking with strong erosion of the left river border, what produced more downstream an orientation of the flows to the banks, with strong erosion

Grijalva River - Mexico 47 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Carrizal Samaria

Strong erosion

• The Carrizal riverbed will continue widening, with agradation of the bed • However, the Samaria riverbed rises probably more rapidly

Grijalva River - Mexico 48 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist WEIR STRUCTURE TO CONTROL FLOW IN CARRIZAL

Grijalva River - Mexico 49 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 50 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 51 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist IMPACT OF WEIR STRUCTURE • Besides bank erosions, the sediment deficit may cause ever more degradation of the riverbed, with a risk for destruction of bridges and other fluvial structures (Comment: there was a very important exploitation of riverbed material in Carrizal) • … or the destruction of the weir during a flood event, by deepening of the riverbed

Grijalva River - Mexico 52 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist IMPACT SAMARIA BRIDGES • The Samaria bridges continue having effects on sediment retention of sediments, riverbed aggradation and formation of bars & canals

• This riverbed shape would cause even more bank erosion, resulting as usual with ever more protection

Grijalva River - Mexico 53 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist IMPACT SAMARIA BRIDGES • A groyne field has been constructed to protect the right bank of the Samaria upstream of the bridges. • However, these protection works are not very effective, as the river flow attacks the bank with an oblique orientation.

Grijalva River - Mexico 54 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist IMPACT SAMARIA BRIDGES

Puentes Samaria

Grijalva River - Mexico 55 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist Grijalva River - Mexico 56 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist 2000 Samaria meandering (canaliform)

O v e r la n d f lo Samaria w

braided in 1 9 9 9

Carrizal canaliform

Grijalva River - Mexico 57 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist SOLUTIONS ? 1. Avoid rapid fluctuations of the flow discharge en Peñitas (new compensation dam?) 2. Training the Samaria river between the bifurcation and Samaria bridges (proposal with three tipes of structures): • A guiding structure with piles, mesh and stones • A series of permeable groynes, with piles and mesh, and longitudinal one connecting them (retard structures) • Bottom vanes to incise the channel (Possibly, through helical flow effect)

Grijalva River - Mexico 58 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist RIVER TRAINING PROJECT

InitialInitial schemescheme -- conceptconcept J.J.J.J. Peters,Peters, 20032003

Grijalva River - Mexico 59 Prof. Ir. J.J. Peters | VUB | Consultant - River specialist