Bayco-Reservoir

Bayco Reservoir

Background

Overview:

Damages caused by torrential rains, historically occurring on the left margin of the Mundo river in urban and agricultural areas, have been considered as highly catastrophic in many occasions, so it became necessary to urgently establish a defense and canalization plan to be implemented in the area subject to the study.

Thus, the General Directorate of Hydraulic Works approved the public information file of the Segura Basin General Flood Defense Plan on November 12, 1986, within the Public Investment Program framework.

The anticipated actions of the General Defense Plan included, in particular, the Defense and canalization of the main affluents on the left margin of the Mundo river.

Dam crest
Dam crest.

After the catastrophic damages caused by the flash floods of July and October 1986, the Official State Gazette published Royal Decree 4/1987 dated November 13, whose attachment nº 2 literally quotes the investment for the execution of the necessary works on the left margin of the Mundo river in Albacete included in the Defense Program.

In May 1987, after the districts affected by the floods held meetings with national, Autonomous Community of Castilla-La Mancha and Segura Hydrographic Confederation authorities, asking for a defense plan for the basin of the Mundo river; road engineer Andrés Martínez Muñoz drafted the Mundo river left margin flood study, describing the serious floods periodically occurring in the plains of the Mundo river and its affluents, especially in the Minateda rivebed.

Likewise, during the drafting of this study, a meeting was held at the request of the Directors of Planning and Agricultural Policy of the Autonomous Community of Castilla-La Mancha with RENFE and experts working for the Segura Hydrographic Confederation, where they point out possible actions to undertake by the different coordinated agencies.

On July 18, 1989, the Technical Specifications for the technical assistance tender for drafting the Bayco riverbed dam project study in the municipality of Ontur (Albacete) were approved.

On September 13, 1989, the call for tender was issued, and the contract awarded to Proyecto y Control, S.A. (PYCSA).

The project of the dam in the Bayco watercourse was first drafted in April 1990, with Andrés Martínez Muñoz as Project Manager Engineer assigned to the Segura Hydrographic Confederation.

Mouth of the superface spillway
Mouth of the surface spillway.

Later on, in September 1990, a Report from the Dam Supervision Service was drafted, signed by Gaspar Zaragoza Gomis, presenting a series of recommendations to be taken into account during the execution of the works.

The Basic Project drafted was approved on April 11, 1991.

By means of the resolution dated April 26, 1991, the General Directorate of Hydraulic Works announced the call to tender for the works of Project 04/90, Bayco or Ortigosa riverbed dam; a tender admitting optional changes in order to improve flood control.

On July 30, 1992, the Directorate of Hydraulic Works decided to award the execution of works to Fomento de Obras y Construcciones S.A., known today as Fomento de Construcciones y Contratas S.A., with the Optional Solution Nº 2 developed in its Tender Project, giving a 2 month term from such date for the successful company to draft the final Construction Project.

Such directive was completed in September 1992, presenting the Bayco or Ortigosa Dam Construction Project (Albacete) for consideration with key 07.105.143/2112 and signed by road engineer Rafael López Manzano.

This Construction Project was approved on December 2, 1992, by resolution of the Directorate of Hydraulic Works with an execution term of 21 months.

On April 26, 1993, the subscription of Contract for the execution of the works was authorized.

The document verifying readiness for construction was signed on June 3rd, 1993, and on the June 4 of the same year the works began.

During the initial phase of the works, some new flood control studies were developed and, at the same time, more precise knowledge of the geo-morphology of the dam site collected, as well as the available materials for its construction.

Such knowledge led to amendment to the initial proposal, showing the need to re-design the dam and its attached hydraulic structures.

On June 2, 1994, the Works Manager Engineer asked for authorization to draft amendment Nº 1 of the 04/90 Bayco or Ortigosa dam project, in the municipality of Ontur and Fuente Álamo (Albacete).

On August 31, 1994, the General Directorate of Hydraulic Works, authorizes the drafting of Nº 1 amendment to the Construction Project of the Bayco or Ortigosa riverbed dam, in the municipality of Ontur and Fuente Álamo (Albacete).

The technical project was finally approved on July 25, 1995.

On June 22, 1995, the Segura Hydrographic Confederation requested authorization to draft the Project of Supplementary Works Nº 1 in connection with the Construction Project of the Dam of the Bayco or Ortigosa riverbeds. This request was grated on July 26, 1995. The drafting of such project was completed in September 1995, and it proposed that the supplementary works included should be developed urgently and that, according to their connection to the works in progress, they should be awarded to the same Contractor.

On August 11, 1995, the Technical Management requested authorization to draft the Modified Project Nº 2 in connection with the Bayco or Ortigosa Dam Construction Project, in the Municipalities of Ontur and Fuente Álamo (Albacete).

On October 16, 1995, the General Directorate of Hydraulic Works authorized the drafting of this project, whose technical approval occurred on October 8, 1996.

The works were completed on December 31, 1996, with a total liquidation budget of 2,239,524,721 pesetas (13,459,814.65 Euros).

The final admission of the works took place on December 30, 1997.

Access

The access to the dam of Bayco´s ravine from Albacete is realized following the described itinerary later: exit of Albacete in direction Murcia for the highway A-30; I turn aside in the exit Ontur close to Tobarra´s locality following the road CM-3215 towards Ontur; already in Ontur there takes the road CM-412 towards Poplar. To approximately two kilometres and a half of Ontur´s locality there takes a detour put up signs to the left side that leads to a rotunda from the one that one can accede to the coronation of the prey for his left stirrup and to the House of the Administration. The total length of the tour from Albacete is of approximately 72 km.

Since alternative access describes the following itinerary: exit of Albacete in direction Alicante for the highway A-31; after happening close to Monte Aragón´s Chinchilla, detour towards Pétrola for the CM-3255; in Pétrola the CM-3214 takes up to The Anorias and from here, the CM-3211 towards Poplar; at the entry of this population the CM-412 takes towards Ontur and to approximately 7 km from Poplar divides to the right the approach road to the dam.

The location of the reservoir can be seen in the following map:


Characteristics

Situation and geographic features of the river and basin
SITUATION OF THE DAM
Province
Albacete
Municipal territories
Ontur and Fuente Álamo
Hydrographic basin
Segura
BASIN DATA
Surface of the hydrographic basin
245.00 km²
Maximum height of the dam
1,051.00 m
RESERVOIR DATA
Surface of the reservoir at the Maximum Normal Level (MNL)
111.54 ha
Capacity at MNL
6.20 hm3
Spot height at MNL
686.00 m

Dam data
DAM BODY
Type
Breakwater with central impermeable core
Map
Straight line
Top spot height
697.00 m
Height from foundations
43.00 m
Top longitude
648.00 m
Bed spot height of the closed area
670.00 m
CHUTE
Total number of chutes
1
Drain capacity at Flood Level Project (FLP)
26.0 m3/s
Adjustment
Front drain of the stationary lip

Detail of one of the lighting poles in Isabelle style for the top lighting
Detail of one of the lighting poles in Isabelle style for the top lighting

Purpose

The main purpose of the dam of the Bayco watercourse is the lamination of floods produced in such a watercourse, as well as in the ones of Cepero and de Jaraba; so, the purpose is to limit the maximum floods coming to the urban core of Ontur and to the Minateda watercourse, draining in its bed.

As a consequence of this lamination of floods, it is reduced the peak of the hydrograms crossing the Minateda watercourse and going to the Camarillas reservoir, above the Mundo river, allowing such a river to transfer its floods to the Segura river with a more reduced flow, which represents the main purpose of the General Defence Flood Plan in the Segura basin.

Basis for topographic monitoring, collimation and fixed recorder for the collimation of the left wall
Basis for topographic monitoring, collimation and fixed recorder for the collimation of the left wall


Territorial and Administrative Context

Physical features of the basin.

The Bayco riverbed begins at the confluence of different watercourses, such as the Cepero and the Jaraba; such a confluence takes place near Sainetes, a village located 3 km to the west of Fuente Álamo.

The catchment basin, up to the dam enclosure, has a surface of 245 km2. It is fan-shaped, and its section are defined by a series of small mountains, hills and minor mounds.

To the north, it limits with the Júcar basin. This Northern divide is marked by a series of small mountains, among which is possible to highlight, from east to west, the Arabinejo mountain (1,051 a.m.s.l.), Miralcampo, the Muela mountain(1,021 a.m.s.l.) and the Romeral hill.

To the northwest, the Pinilla mountain separated it from the Charcos basin; and to the southeast, it runs through the Conejeros mountains and the high Madroño, and it limits with by the middle basin of the Tobarra stream.

To the south, the foothills of the upper Madroño and the Parda mountain separate it from the semi-endorheic plains of Ontur and Albatana. Although in these plains the Bayco riverbed flow is negligible, topographically, these lands are tributaries of the lower basin of the Tobarra stream or to the Minateda riverbed, as it has become obvious during important floods.

To the southeast, the basin shares a boundary with the Cañada de Albatana stream, which is also included in the Tobarra stream catchment basin.

In general, the basin is almost flat,the soil is made up of Plio-Quaternary clays and silt, apart from the Jurassic limestone and dolomite crests that shape the small mountains that create the divide.

The length of the largest riverbed is 18.8 km, beginning at an elevation of 970 m and ending at 670 m in the dam enclosure. Therefore, the average slope is 1.6 %.

The basin time of concentration is 4.8 hours.

The basin pluviometry is scarce and erratic. An average yearly rainfall of 366 mm is estimated, alternating long periods of drought with sporadic, short-lasting, heavy rains, and very intense rainfall.


Environmental information.

The area of the Bayco reservoir is characterized by a tempered continental Mediterranean climate.

Based on all of these parameters, it is clear that its climate favors physical erosion processes of certain intensity (torrential rains, frost, etc.), thus, creating certain typical morphological features.

The area's water network does not have important hydrographic arteries but is limited instead to just seasonal watercourses, ravines and streams.

The hydro-geological features of this area are associated to the water conditions of the materials.

Erosion is an important factor in this area, given considerable soil losses as a consequence of external processes (rains, weathering, etc). During the rain season, erosion is intense, and it is favored by the scarcity of vegetation which implies significant material hauling.

Bayco dam construction commemorative monolith
Bayco dam construction commemorative monolith

It has been estimated that soil depletion due to laminal hydric erosion and irrigation channels is approximately 57 t/ha, which places this area within the sub-desert zone of the south-eastern part of Spain.

The potential of these soils is based on their physiographic location and erodability; the firmest slopes are used for forestry and the softer slopes for grains and grapevines, representing a potential reserve in the expansion of district irrigation.

The Rivas-Martínez agro-climatic classification places the Bayco basin in the meso-Mediterranean floor, Manchegan section of the Castellano-Maestrazgo-Manchega province. The natural vegetation belongs to the sclerophyllus formations of leathery, evergreen leaves, a defense mechanism against the arid environmental conditions of the area.

Potential vegetation would be made up of holm oaks (Quercus rotundifolia), with a shrub border of groves. The current vegetation is grouped in three natural units: fields, thickets and trees.

The fields are grassy areas made up of leguminous and grassy plants, associated with different shrubs: thyme, rosemary, etc. They frequently grow on old esparto fields, currently abandoned, creating the esparto-fields unit.

Thyme, gorse and rosemary thickets occupy a large area of the basin, especially on sharp slopes which are not suitable for agricultural exploitation. Cattle feeds there.

Holm oak and pine forests appear at the highest basin elevations, generally surrounded by thicket and representing the basis for development of the animal community.

On cultivated land, it is possible to find groups of larks, passerines and finches, as well as many corvids.

The plant units support an important bird wildlife, as well as many mammals common in Spain: rabbits, hare, etc.; nevertheless, the predominance of cultivated land over natural vegetation translates into the wildlife characteristics of that unit.


Geology and seismology.

Geology

The area occupied by the Bayco reservoir is the link between the Baetic and Iberian Systems.

Downstream dam shoulder, crops and irrigation systems
Downstream dam shoulder, crops and irrigation systems

Southwards from the reservoir, from east to west, we find structures clearly belonging to the Pre-Baetic domain, as the northernmost and external part of the Baetic System, whereas northwards, structures are Iberian, in a north-south direction.

In this area, it is possible to observe Baetic structures, i.e. east-west, such as the thrust and

the folds of the Madroño Mountain and the upfold of the Parda mountain. To the north, towards the tail end of the reservoir, it is possible to observe folds in the north-south axis, and formations lying to the west, typical Iberian features. The Morras, which make up the dam's left abutment, have a dome structure, possibly due to the impact of two upfolds: one is Iberian in a north-south axis, while the other is Baetic, in the ENE-WSW axis.

In the reservoir area, the following stratigraphic soils are found:

  • Jurassic:
    Jurassic soils emerge in the reservoir basin and the surrounding mountains, such as the Madroño and the Parda mountains, as well as in the small isolated hills, surrounded by recent soil covers (alluvial and colluvial).
    The lithological types observed in the reservoir area are dolomites, groups of dolomites and limestone, and alternate layers of limestone and silty marl.
    Dolomites practically make up the entire left abutment of the dam.
    Groups of limestone and dolomites make up the right abutment of the dam. The limestone emerges on the left margin of the enclosure, downstream from the dam axis and in isolated hills of the reservoir's tail end. Limestone and marly limestone make up the small ravine surrounding the Morras hills on the south and southeast.
     
  • Cretaceous:
    Thet appear next to the right abutment of the dam and, generally, over the entire northern watershed of Madroño mountains, under the Jurassic dolomites and limestone and in mechanical contact with them. They appear as a set of detritic materials particularly tectonized and laminated.
    Grey, green and red clays, white sand, red grit, conglomerates of round stones and black gypsum have been observed.
     
  • Continental Tertiary:
    Formed by fluvial deposits and alluvial fans, made up of conglomerates and, to a lesser extent, red grit and clay.
    The conglomerate appears as a compact rock, made up of rounded and sub-rounded calcareous stones, cemented by a red calcareous matrix.
     
  • Quaternary:
    It makes up most of the reservoir basin soil, covering the most ancient land. It is made up of slope and fluvial deposits, clayey-lime lithology with lots of sand, also containing gravel and some blocks.
    In the geological cartography, it has been possible to distinguish the alluvial deposits occupying the middle of the valley and are made up of brown clays or beige lime clays with layers of abundant lime-clayey gravel and sand lenses, not too consolidated and highly waterproof.
    It has also been possible to distinguish colluvial fan-shaped deposits, with a thin lens-like section. They are made up of whitish or light pink fine sand and marly lime, including angular and sub-angular marl stones and dolomites. Their vertex is on the sides of the mountains and its bottom in the centre of the valley, as its origin is in layers of diffuse runoff. They are quite waterproof.
    The alluvial-colluvial deposit present in the area is a mixed, heterogeneous deposit of anything from clayey alluvial to limey colluvial. They have a characteristic pink color.
    Eluvial deposits have also been found, which have been essentially formed by alteration of the substrate with little movement. Eluvial deposits over red calcareous rocks are scree and decalcification clays, while the Cretaceous sands and clays produce loose sandy clays.
     

Seismology

The Bayco basin reservoir is located, according to the Seismic Resistance Construction Regulation (NCSE-02), in an area with a basic seismic acceleration of 0.07 g in the Ontur municipality, which is the nearest town to the reservoir.


Situation

As it has been exhibited previously, the dam of Bayco´s ravine places in the actions of defense of the left margen of the river World, inside the General Plan of Defense against Avenues of the Cuenca of the Segura.

Bayco´s ravine is in the zone Suroriental of the province of Albacete. After happening for Ontur´s locality, riverbed gets lost in Albatana´s plains.

In case of important avenues, the wealth generated in his basin join finally to Tobarra´s creek or Minateda´s ravine, tributary for the left margen of the river Mundo, which comes together with this one in the tail of the reservoir of Lobbies.

The dam of Bayco´s ravine is upstream from Ontur´s locality, to a distance of 2,5 kilometres.

The busy areas belong to the municipal areas of Ontur and Fuente Álamo.

U.T.M. coordinates:

Reference system ETRS89. Time zone= 30
X=630.460
Y=4.277.895


 

Certificación ENS media
Certificación ISO 27001