The south end of the Chilean broad gauge
Transandine Railway by Lonquimay
REPORT ON THE INSTRUMENTAL SURVEY UNDERTAKEN BY ORDER OF THE MANAGEMENT OF PUBLIC WORKS
At the start of the month of December of the year just past , I had the honour of being commissioned to undertake an instrumental survey in order to determine the standards and route of a railway, which leaving Curacautin would reach the boundary with the Argentine Republic. This railway ought to be considered as the Chilean section of a transandine railway of 1.68 m. which would link the railways of the same gauge in the Argentine and Chile.
I carried out this survey during the period 1 January and 12 February of the present year. It was not possible for me to start the preparation of the associated plan at once as I had to attend preferentially to matters associated with the railway under construction from Selva Oscura to Curacautin, whose technical inspection is my responsibility. For this reason, it is only now possible for me to submit the present report, the plan and the associated line of levels for your consideration.
Before presenting what is relevant to the commission to which I have referred, I believe it appropriate to record some earlier matters.
For many years in this area, the South Argentine Railway Company has held a concession to extend the Neuquén by the route called that of Las Lajas to the frontier with Chile in Paso Pino Hachado. At present, the said railway reaches as far as the station called Neuquén, which is about 300 kilometres, more or less, so that when this section is complete, only 140 kilometres remain to reach the frontier with Chile.
For their part, the Government of Chile has advanced a bit with its railways in the direction of this part of the Cordillera, since the line from Púa to Selva Oscura is already built, and the construction from this point to the village of Curacautin is being actively advanced. As luck would have it, in a short time more, a length of only about 260 kilometres will remain to join the railways of one side to the other of the Andes, being 140 in Argentina and 120 in Chile.
For a long time since, there has been the proposal in the Argentine to extend the railway from the [river] Neuquén to Paso de Pino Hachado, following the Las Lajas route in order to link the Chilean and Argentine railways of the same gauge. Following this proposal, the South Argentine Railway Company had surveys carried out by a commission of English engineers, both in Argentine and Chilean territory. The surveys by this commission, on the Argentine side, were made made between Las Lajas and Paso de Pino Hachado, without encountering serious difficulties, according to news which I have received, but the same was not true from this pass towards Chile, since the commission saw the necessity of following various routes on leaving Paso Pino Hachado. First surveyed were the banks of the [river] Bio-Bio to join to the railway from the town of Mulchen. Then surveys were carried out to cross the Lonquimay range to reach Curacautin and finally, understanding that follows the [river] Liucura avoided the Bio-Bio as far as the Galletué lagoon, and from thence the valley of the [river] Allipen to reach Freire station.
From those surveys, those carried out in the direction towards Mulchen and towards Curacautin gave bad results; while I do not know if the third one, the one carried out to Freire, had equal lack of success and I am inclined to believe that this was so, as the South Argentine Railway Company ordered other surveys, abandoning the route via Las Lajas and Pino Hachado to pass through Pucon and Villarica to junction with certainty with the Chilean railways at Loncoche station.
From what has been said, it is clear that the said company has had a very marked preference to solve this question using the Las Lajas and Paso Pino Hachado route. Solely the failure of the surveys carried out in Chile have obliged them to seek another route, with the policy remaining if a section in Chile with good conditions could be found, they would persist in their original proposal to continue the Neuquén railway through Las Lajas.
The Government of Chile likewise have demonstrated an interest in discovering the most appropriate way of linking the railways of 1.68 m. gauge on both sides of the Andes, and has commissioned surveys, or reconnaissances, on more than one occasion to achieve this end. Among others, there is the reconnaissance of Omer Huet from Curacautin to the frontier with the Argentine Republic, commissioned by the Government; the one entrusted to Dominco Duran for the route via Villarrica; and the last, recently entrusted to the undersigned, by Lonquimay, with which I will now occupy myself.
PURPOSE OF THE SURVEY
As was stated at the start of this report, the task, with which I was entrusted, had as its purpose the establishing the route of, and the standards for, a length of railway of 1.68 m. gauge between the village of Curacautin and the frontier with the Argentine Republic in Paso de Pino Hachado, or another near to it.
It may be seen, then, that the proposal which leads to this commission, is to persevere in the search for an appropriate solution which will result in a favourable resolution to the strong desire of the South Argentine Railway Company, of employing the route via Las Lajas and Paso Pino Hachado for the continuation of the railway from the Neuquén, and converting it into a transandine railway. It is very probable that its realization would hang on the instrumental survey which I have been charged with undertaking.
From the data which this report, plan and line of levels accompanying it, contain, it is at once seen that I have had the good luck to achieve this very satisfactory result.
Given that I was in the area in which the route was to be sought, I considered it a priority to determinine the railway's crossing points in the range forming the frontier with the Argentine Republic, and principally in that which separates the Malalcalmello and Lonquimay valleys, which I will designate with this latter name.
This range, that is the one of Lonquimay, is in general lying south to north, formed of a central massif or trunk, to which is joined a series of buttresses, or strings of salient fells, which extend in all directions, reaching considerable heights above sea level, of which I have been able to observe some in excess of 1,800 metres. The almost complete very dense cover increases the difficulties when it is necessary to survey it.
This range, as has been said, separates the valley of Malalcalmello from that of Lonquimay, which in the first part takes the name of Punta Negra, in this way it disrupts the opportunities which these valleys present for the building of a railway. It was advisable to study this before advancing, since it was evident that it presented great difficulties, which were caused by the difficulty of surveying the mountain with all its ground cover.
After some days employed in making observations and reconnaissances of that range, I was not persuaded that it was necessary to firm-up the surveys involved between the head waters of the Río Cautin, which are close to the south east hill side of the Volcan Lonquimay, and the massif of the Sierra Nevada over a distance of 15 kilometres.
In this part of the range various ravines or canyons branch off on one side or the other in whose heads are gateways which look into the valleys of Malalcahuel and Lonquimay. Some of the gateways are very well hidden and are difficult of access. Of these I reconnoitred four, which resulting in finding one which amply satisfied the proposal which was being pursued.
This gateway is the second of those which are to be found going northwards from the extreme south of the Sierra Nevada, since there it would be possible to cross the range with a tunnel 1,700 metres long at a height of 1,070 metres above sea level.
Achieving in this manner a satisfactory crossing of the Lonquimay range, it was also necessary to fix the place for crossing the frontier with the Argentine Republic.
The undersigned had knowledge that the commission appointed by the South Argentine Railway Company had achieved in their surveys by Paso del Pino Hachado a crossing of this range, a good reason why I considered it to be first choice; but the observations which I undertook in this pass, and also in the Mallin Chileno, which is near to it, resulted in great difficulties for traversing them with a railway, and I formed the conviction that to reach them it was necessary to use a rack for about 10 kilometres, or by simple adhesion, it would be necessary to use a gradient of 2%, more or less, over a length of 20 kilometres which would have to start at Paso del Arco, which is located a bit to the south of them and follow very closely the frontier between Chile and the Argentine.
This circumstance, or that of reaching Paso Pino Hachado and Mallin Chileno, it was necessary to climb through the Paso del Arco, and from there continue the climb towards them, I came to think that this last pass, was, amongst the three, the one one which must be selected for crossing the frontier range, always given that the Argentine side would not present serious difficulties, which would make it inappropriate. Happily these difficulties don't exist according to the information which I have been able to gather-in.
By Paso del Arco the range may be crossed without a tunnel by a railway of 1.68 metre gauge using only a gradient of 1.75% without the need to follow more than three kilometres on the southern side slopes of the Río Liucura and continue with this same gradient by Mari-Menuco to the said pass, whose lowest part is at 1,370 metres above sea level.
Although I found that the Paso del Arco would resolve matters in a satisfactory way, I considered it advisable to visit the Paso de Icalma which is some 10 or 12 kilometres to the south of it and at a substantially lower level; but I was persuaded that to reach it from the Argentine side, there were serious difficulties foreseeable, which you render it unsuitable for the purpose.
Having determined that there were places to cross the Lonquimay range and at the frontier, the survey of the rest was carried out without major difficulty.
The line would leave Curacautin station and would proceed for a short distance in the vicinity of the Loncocapira stream; then leaving it, it would advance on the north side of the public road which runs from Curacautin to Lonquimay to cross it at Km. 26 and follow it on the south side to Km. 32. From there it would follow in the vicinity of a nameless stream, which is an affluent of the Río Cautin, entering the Lonquimay range by the Malalcahuello side. At Km. 38 it would turn towards the east, following this direction till meeting the second of the gateways of that range which is located towards the north of the Sierra Nevada counting from its extreme south. There is would cross the range with a tunnel 1,700 metres long at a height of 1,070 metres above sea level and located between Km 41 and Km 43. From the end of the tunnel it would follow a line along the hill sides, which overlook Punta Negra as far as Km 50, and continue along the Lonquimay valley, following the left bank of the river of the same name, passing close by the village of Villa Portales, and at the foot of San Pedro fell, some four kilometres before its discharge into the Rio Bio-Bio. Once across that river, it continues along its right bank, getting further away from it until it reaches the banks of the Bio-Bio, from where it would follow its left bank to reach Km. 95, continuing by the other side to a little before the Río Liucura. From that point it would direct itself along the side slopes which form the gully of this river as far as Km 112, where it would start to climb by Mari-Menuco to reach Paso del Arco.
DESCRIPTION OF THE LAND
The land which the route of the railway traverses is presented as follows: Between Km 0 and Km 14 there are a few gentle undulations, in which the cuttings and embankments will be shallow. From Km.14 to Km. 27 the majority is made up of semi-hard not very steep side slopes, with the exception of the kilometre between Km. 25 and Km. 26 which has hard rock and the earthworks will be a serious consideration. Between Km. 27 and Km. 41+350, or as far as the start of the tunnel, it is slightly undulating, with gentle slopes of soft soil, which will result in shallow cuttings and embankments. Between Km. 41+350 and Km. 43+050 will be the Lonquimay tunnel which crosses the range with a length of 1,700 metres. The ground appears to be formed of volcanic rock. Between the end of the tunnel (Km. 43+050) and Km. 48 are somewhat steep side slopes with some 30% hard material, with routine earth moving. From Km. 48 to Km. 77 the land is almost flat, with very little earth moving in cuttings and embankments. Between Km. 77 and Km. 93 these are some undulations of little consequence, the quantity of earthworks will be less than usual, the soil is semi-hard. From Km. 83 to Km. 90 it is almost flat and soft. Between Km. 90 and Km. 97 there are some low but somewhat steep side slopes, probably made up of 50% soft material and 50% semi-hard. Between Km. 97 and Km. 106 the land is almost flat, in which there will be very little earth movement required. From Km. 106 to Km. 126, which is the end of the route, there are many undulations, but of soft material which is mostly composed of volcanic ashes and sands. The amount moved will be of some consideration without calling it great.
SPRINGS AND MINOR WATER COURSES
The route will also traverse more or less some fifty small brooks and springs and the following streams and rivers: Negro, Blanco del Indio, Malalcahuello, Naranjo, Lolén, Pedregoso and Hualgopulla streams and the Cautín, Lonquimay, Bío-Bío, Pehuenco and Liucura rivers.
LINE OF LEVELS
The line of levels of the trace in general terms is in the following form: From Km. 0, level 528.25 to Km. 41+350, level 1069.50, which is the start of the tunnel, rises with various gradients of which the steepest is 1.75%; there are two horizontal lengths; between Km. 41+350 and Km. 43+050 there is a horizontal for the tunnel at level 1059.60; from Km. 43+050 to Km. 48 it has a gradient of 1.75%; from Km. 48 to Km. 59 it falls gently; from Km. 108 to Km. 125 which is in Paso del Arco, there is a continuous gradient of 1.75%; and finally between Km. 125 and Km. 126 which is the end of the route, it is horizontal.
It appears, that for the railway to serve the area conveniently, it would be sufficient to provide five stations for just now, which on the plan are shown as follows: Hueñivales at Km 13+300; Malalcahuello at Km 30+700; Lonquimay at Km 62+300; Lolén at Km 76+200 and Liucura at Km 102.
AREA OF INFLUENCE
Between Curacautin and Malalcahuello, that is between Km. 0and Km. 41, there are vast lands surrounded by the mountains which are little worked and in which are good construction woods are worked. In these same lands there are extensive fields, some of them irrigated which produce wheat, oats and abundant pasture.
The railway in this area would serve an area on both sides of the Río Cautin of at least 100,000 hectares.
Between Punta Negra and Liucura (Km 108) are the valleys of Lonquimay, Bío-Bío, Rahue, Mihauquen, Liucura and others which are suitable for the rearing of bovine and ovine animals. The pastures are abundant, and are good producers of lucerne, of which there can be up to three cuts in a year. There are various land owners who grow lucerne, among whom is don Guillermo Schweitzer, who has thirty to forty fields of it.
They also grow dactyl, dastyilia glomerata, well, which makes excellent forage and can be baled like alfalfa and sold in the same markets.
The extent of the land formed in the valleys and on the hill sides is good for the rearing of livestock, and for the growing of pasture. It may be conservatively estimated that there is 150,000 hectares which may be served by the railway.
In the area of Lonquimay there is a certain abundance of layers and veins of copper to be found, which although presently evident in inferior quality, perhaps after prospecting and reconnaissance, it will become a mining centre of importance. I have also heard talk of the existence of layers of coal and oil fields.
Without doubt, the principal reason for the justification for building a railway through this region, is not on the importance of its area of influence in the Chilean side, but in the service it would render to the commerce of transport with the Argentine Republic, to which I need not refer as it is self evident.
Ferrocarril trasandino por Lonquimay (Memoria del reconocimiento instrumento practicado por orden de la Direccion de Obras Públicas), Oscar Parodi, Anales del Instituto de Injenieros de Chile, June 1910.