Wellington would not risk his army defending deep into Portugal unless the conditions were right. Instead he implemented a scorch earth policy to prevent the invading French from living off the land. He fought and defeated the French at Busaco on 27 September, but knew he could not stop them. Late on 28 September he ordered the army to continue its retreat. The officers and men of the Light Division reached Coimbra two days later after marching 36 km. They were surprised by that the Army’s Commissary Department was unable to evacuate all their stores. Tons of food and equipment was destroyed or left for the French. The next day they marched to Condeixa and found even more supplies. Lieutenant John Kincaid of the 95th Rifles noted that "the commissary officers handed out shoes and shirts to any one that would take them, and the streets were literally running ankle deep with rum, in which the soldiers were dipping their cups and helping themselves as they marched along."
Lieutenant James Fergusson of the 43rd also noticed the large amount of stores being destroyed, including cavalry equipments [sic], hospital supplies, tea, brandy, shirts, shoes, troswers [sic], and tobacco. . .”
The situation was the same in Pombal, 27 km further south. It too was another supply depot. Captain Leach of the 95th Rifles wrote that “So inveterate is the propensity of drink in the soldier, that, in spite of every precaution, many of them contrived to get drunk by dipping rum out of the streets, on our march through the town, in tin cups, or in any vessel nearest at hand.”
Lieutenant Henry Oglander of the 43rd Foot said that this neglect was deliberate on the part of the Commissary's part. "At Condexa considerable stores of liquor, salt provisions and tents were destroyed. The destruction and abandonment of stores is probably to be attributed not as the fault of the commander in chief, who cannot overlook the execution of every minute detail but to the ignorance and carelessness not say disinterest of the Commissariat. The later motive indeed I much fear had its weight, as any irregularity in their accounts may be easily concealed by adding the deficiencies caused by these scams to the list of articles destroyed already, which, I should think from the hurry and confusion inevitable in such circumstances, it would be next to impossible to discover."
My question is considering the retreat was planned for months why was the commissary department caught by surprise?
You bring up some very good points, especially about the reliance on local carts to move the material.
Dear @Robert Burnham Would it be possible? Would it be worth? Were there enough transports? Was there sufficient time? and @Mark S Thompson how could the "Portuguese Government" give "evacuation orders" to British Army depots or even Portuguese Army depots? Coimbra depots were fundamental to support the allied army in the Beiras, and almost the only large depot available to do that after the french set siege at Almeida on August 1810. The Almeida siege was much shorter (only 11 days) than what was expected, due to the unfortunate event of the gunpowder storage explosion (26th August 1810), and then there was a need to support the retreat (the case of Pombal depots, but also depots at Leiria, Peniche, Óbidos, Caldas da Rainha and Torres Vedras, on the West side of the Candeeiros and Montejunto Mountains, and at Tomar, Punhete (Constâcia), Abrantes, Santarém and at barges on the Tagus, on the East). The goods in Coimbra were from two sources (overseas and local). The overseas goods were transported through the rivers Tagus (from Lisbon to Santarém and Abrantes), Mondego (from Figueira da Foz to Coimbra) and Douro (from Porto to São João da Pesqueira, somehow more limited in the summer months). The overseas goods were transported along the Mondego, from the port of Figueira da Foz to Coimbra, from where they were land transported to the troops, through the upper valley of the Mondego, using mules or rented carts. River transport was fundamental to take the goods inland due to volume and the poor state of the roads. For the transport of supplies between depots the Peninsular commissariat relied heavily on local carts, hired or requisitioned for each stage of the journey. But these were in high demand from the owners and population to evacuate to Lisbon. Other solution would be to ship it down the Mondego and then to Lisbon.
So they had the negative conjunction a considerable distance from Coimbra to the Lines (120 miles, meaning at least 4 to 6 days of a logistical column), the need to support the retreat, lack of transports, and awful roads, that were full of people moving South, in hilly and mountainous terrain.
Of course, the alternative was the distribution to passing units and the destruction of remainder goods.
Actions well-reported in letters: "Some irregularities took place after Coimbra was abandoned, and the Commissary-General admitted to destroying 20,000 rations of corn, 35 puncheons of rum and 6 wine pipes to prevent their capture by the French." (PRO War Office 57/38, Kennedy to Gordon, 14th October 1810. ) cited by Redgrave, T. M. O. (1979). Wellington’s Logistical Arrangements in the Peninsular War 1809-14 (King’s College, University of London), p. 158. And the descriptions of witnesses like the ones referred by @Robert Burnham, but others that are very vivid like Schauman in Chapter 17 (Schaumann 1778-1840, A. L. F. (1924). On the Road with Wellington ... Edited and translated by Anthony M. Ludovici. (A. M. (Anthony M. Ludovici 1882-1971, Ed.). London: William Heinemann, 1924). On the subject I suggest the reading of the two above referenced texts as well as the bi-lingual book (Portuguese and full English translation): Espírito Santo, G. A. do., & Brito, P. de. (2012). A logística do exército anglo-luso an Guerra Peninsular: uma introdução | Introduction to the anglo-portuguese army logistics in the Peninsular war. Lisboa: Tribuna da História. Here: bit.ly/Army_Log_PW And the two following theses: 1. Kirby, T. T., & Army, U. S. (2011). Wellington supply system during the Peninsula War. U.S. Army Command and General Staff College. 2. McLauchlan, T. M. (Tina M. (1997). Wellington’s supply system during the Peninsular War, 1809-1814. McGill University, Montreal.
Don’t forget many Commissary officers were found to have run from Talavera with the Spanish.
There were serious issues with commissary officers throughout the war, the did improve, with time. Commmisary officers were not front line soldier. They weren’t the bravest, with some exceptions, when they saw the British army retreating, they probably decided discretion was better than valour and dropped their duties and hoofed it for Lisbon. Wellington spent an inordinate amount if time developing the commissary/supply system, he lacked officers to whom he could delegate staff duties in the early years. The plans for this part of the campaign were held secret til the battle of Bussacco. Wellingoon Had limited time and resources, he rightly focused them on fighting that battle then withdrawing to the Lines of Torres Vedras.
I am sure that Wellington blamed the Portuguese government for not issuing the evacuation orders soon enough. He also (I recall from memory) blamed the civilians for waiting too long. However, that does not explain why military stores were still at Coimbra and other towns to the south. Did Wellington expect to stop the French at Bucaaco? If he did, he did not plan it very well.
Was it simply a lack of available transport?