In 1912, Baratta founded the "Società Lunense Acqua e Forza", becoming its Managing Director. 49 founding members took part in its incorporation, who underwrote 5,000 shares with a nominal value of 100 lire each, with varying quotas ranging from 5 to 400 shares and an average of about 100 shares each: at the time, it was a company with a large shareholder base. The initial share capital was 500,000 Lire, there were 49 founding members, and the corporate purpose was "the construction and operation of plants for the use of drinking, irrigation and industrial water and for the production and use of energy". Subsequent increases in capital and the incorporation of other companies in the group expanded the shareholder base, which reached 300 shareholders, to whom an annual dividend has always been regularly distributed, even during the most challenging times.

In 1913, Baratta received the Gold Medal from the Ministry of Public Works at the Verdiana Exhibition in Parma (Fair of the Apennines) for the projects of Lagastrello, Cedro, Taverone, Enza and Brasimone. In that same year, given the precarious health and hygiene conditions existing in La Spezia, the Municipal Administration decided to issue a public invitation to tender for the construction of a new aqueduct capable of providing 10,000 cubic metres per day of drinking water.
Four projects were submitted:
1.The Società Generale delle Acque per l'Estero, based in Paris, proposed for the withdrawal of groundwater in the vicinity of Vappa;
2. Fausto Baratta proposed the withdrawal of water from the under flowing bed of the Magra river in the vicinity of Fornola and channelling it to the city;
3.The Azienda Municipalizzata dell'Acquedotto of La Spezia proposed the use of surface waters of the Magra and Vara rivers with ozone purification;
4. Mauro Duchini proposed the diversion of the spring waters in the vicinity of Chiesaccia in Garfagnana and their subsequent channelling to La Spezia.

The project assessment commission the was chaired by Professor Giovanni Capellini and included Professor Giuseppe Colombo of the Milan Polytechnic, known for having published the famous "Manuale degli Ingegneri".
The commission completed its work in 1914 and put forward Baratta’s project to the Municipality of La Spezia, concluding that "...the project, the research and studies carried out assiduously and commendably by the designer Fausto Baratta have led to the completion of the project without varying the agreed cost, and the project itself is adequately prepared and ready for practical implementation.
Furthermore, the extraordinary increase in the prices of machinery, pipes and works in general represents a significant discount which the Municipality must take into account, given that Società Lunense has maintained the original price". That same year, Baratta was awarded the Gold Medal for Civil Valour, which was given to him at the International Hygiene Exhibition in Genoa, where he illustrated the executive project of the La Spezia aqueduct.

In 1915, construction work began on the Fornola Aqueduct, which by 1916 was already able to supply part of the city of La Spezia and the facilities of the Navy, including the military refrigerator of San Bartolomeo, thanks to a network of over twelve kilometres of pipes, with water sourced from sixteen tubular wells drilled on the right bank of the Magra river. The water was channelled into two circular reservoirs with a diameter of 30 metres and a capacity of about 5,000 cubic metres each built on the Colli, above the Batteria dei Cappuccini, at the time used as a monastery. The reservoirs, made of reinforced concrete, are still in operation to this day.
Subsequently, the aqueduct of the city of La Spezia was appropriately enlarged from the initial 10,000 cubic metres/day to 15,000 cubic metres/day in 1925, thanks to the construction of new wells and a cast iron pipe with a diameter of 300 mm, to 20,000 cubic metres/day in 1929, following the construction of a recovery plant in the vicinity of Boschetti, to 30,000 cubic metres/day in 1934, after the construction of new wells and a new pipeline from Fornola to La Spezia with a diameter of 350mm, and to 40,000 cubic metres/day in 1939 thanks to the construction of a pipeline with a diameter of 500 mm from Fornola to La Spezia and new wells with a diameter of 4-6 inches (100-150 mm), which reached a total number of forty-eight and supplied the Electric, Thermal and "Icebox" plants.
In 1975, the Municipality assigned the management of the aqueduct to AMGA (Azienda Municipalizzata Gas Acquedotto), later known as ACAM (Azienda Consorzio Acqua Metano): some of the wells built were used excessively in the 1990s to withdraw drinking water and began to produce brackish water, so they had to be abandoned quickly. During that period, Società Acquedotti Tirreni supplied water to Lerici.

In 1923, the aqueduct of the Municipality of Lerici (La Spezia) was designed by Fausto Baratta. It was conceived to meet the needs of the 9,396 inhabitants of the Municipality, thanks to the construction of three wells in the vicinity of Romito and a pipe with a diameter of 200 mm up to Barcola, with a tunnel-reservoir to channel drinking water to the valley towards the sea via two pipes, one for Lerici and one for San Terenzo: a lifting system, located in the vicinity of Guercio, supplied the villages of Serra and Pugliola. The works started by Società Acquedotti Tirreni in 1924 were completed in 1927 and the management of the aqueduct continued until 1975, after which the plants were transferred to the Municipality at no cost.
In 1975, the Municipality assigned the management of the aqueduct to AMGA (Azienda Municipalizzata Gas Acquedotto), later known as ACAM (Azienda Consorzio Acqua Metano).

In 1924, a project relating to the aqueduct of the Municipality of Arcola (La Spezia) was drawn up: the construction works, which began in 1927 and ended in 1928, were carried out by Società Acquedotti Zona Orientale, which was part of the Baratta group. The company managed the aqueduct until 1975, carrying out a number of significant improvements over the years (the capacity was enlarged to 40 litres per second) and, subsequently, assigned to AMGA.

The Vezzano Ligure (La Spezia) aqueduct was built in 1928 and, by the end of the following year, supplied metered drinking water to individual private users. The aqueduct was designed by Baratta and was built and managed by Società Acquedotti Zona Orientale. The plant consisted of wells in Fornola, a cast iron pipe with a diameter of 150 mm, a lifting pump plant and a "high altitude" reservoir with a capacity of 200 cubic metres. In 1972, its management was transferred from Società Acquedotti Tirreni to the Municipality, which later assigned it to AMGA.

In 1929, Baratta designed the aqueduct of the Municipality of Portovenere (La Spezia) on behalf of Società Acquedotti Tirreni. There was the construction of two pump plants in the vicinity of Fabiano Basso and in the vicinity of Fezzano, a tunnel acting as a reservoir, with a capacity of 300 cubic metres, at 88 metres above sea level in the vicinity of Pezzino, and a cast iron pipe with a diameter of 150 mm that was 4,800 metres in length, capable of channelling the water rquired to meet the needs of the 6,970 inhabitants, including the 489 inhabitants of the Palmaria and Tino islands, who until then were supplied by small local sources that were totally inadequate to meet their needs.
The new aqueduct channelled water from the Fornola well area and was inaugurated in a solemn public ceremony in December 1929 which saw the opening of a spring near the gates of the ancient village of Portovenere. Subsequent upgrades were carried out in the ‘60s with the laying of new pipes including a double submarine pipeline made of polyvinyl chloride (PVC) between Portovenere and the island of Palmaria. The aqueduct was managed by Società Acquedotti Tirreni until 1972 and subsequently by AMGA.

The aqueduct of the city of Sarzana was designed and built in 1930 by Società Acquedotti Zona Orientale del Golfo, belonging to the Baratta group, which, upon completion, was able to supply 12 litres per second. Up until 1929, the city of Sarzana had used a number of small springs and water taken from the under flowing bed of the Calcandola stream for drinking purposes: however, these sources only guaranteed a limited flow of water, especially in the summer.
In the 1970s, Società Acquedotti Tirreni designed and built a new well area featuring four wells equipped with 20-litre per second submersible electric pumps, capable of supplying 7,000 cubic metres of drinking water per day. Due to its characteristics and the method of withdrawal, the water did not require purification treatments. In the ‘70s, the management of the aqueduct and the well area was transferred to the Municipality of Sarzana and subsequently to ACAM.

In 1932, following in-depth hydrogeological studies, Baratta submitted a project for the construction of the Camaiore aqueduct: the construction of this aqueduct, which exploited the deep waters present in the vicinity of Camaiore, made it possible to supply drinking water to residents in the Municipalities of Camaiore, Pietrasanta and Forte dei Marmi.
The aqueduct was built in 1933 and was managed by Società Acquedotti Tirreni until 1985: in that year, its management was transferred to VEA (Versilia Acque) and, today, the plants are managed by Gaia S.p.A.

In 1932, alongside Giovanni Puccio and Giuseppe Orsi, Ettore Antonelli joined Acquedotti Tirreni S.p.A. as Technical Director, a role he held until 1956, when he became chairperson of the company.

In the years between 1940 and 1945, during the Second World War, Società Acquedotti Tirreni S.p.A. continued to provide the service on a continuous and regular basis, despite the fact that no payments were received from users and the headquarters in Via XX Settembre had been bombed. This was accomplished thanks to the commitment and hard work of Ettore Antonelli and all those who worked with him in the spirit of safeguarding the supply of drinking water to the population.

Fausto Baratta passed away in 1948: "... I endured much suffering resignedly, I worked hard and honestly... I die in the bosom of the Catholic religion. I encourage my children to trust in God and not to spend too much time in sorrow... ” were the closing lines of his last will and testament.

Arrigo Antonelli joined S.A.T. in 1961, alongside Mauro Foce, and is the son of Angelo, who was CEO and then chairperson of the company until 1975: in that year, Arrigo Antonelli became CEO of the company, a position he still holds.

In 1963, Società Acquedotti Tirreni constructed a new steel pipe with a diameter of 300 mm from the well area in the vicinity of Romito to Barcola, and new distribution pipes for Tellaro, San Terenzo and Lerici, supplied by five new wells. Capacity reached 12,000 cubic metres/day, equal to 135 litres per second.

In order to supply the city of Viareggio, in 1970 Società Acquedotti Tirreni constructed a new well area in the vicinity of Frati di Camaiore and a pipe with a diameter of 400-500 mm capable of channelling over 200 litres per second to the network: that, added to water from Stiava, was sufficient to meet the needs of the city’s users.
The aforementioned plant was managed by Società Acquedotti Tirreni until 1997.

In 1971, Società Acquedotti Tirreni quickly constructed a new well area in Ressora and a steel pipe with a diameter of 400mm to connect Ressora and La Spezia: the line supplies, among others, the Navy in San Bartolomeo and the high areas of Muggiano.

In 1972, Società Acquedotti Tirreni constructed the aqueduct for Ameglia, Marinella and Marina di Carrara, laying steel pipes with a diameter of 450-500 mm that are still managed by the company to this day. The line is supplied by wells in the vicinity of Ressora.

From 1973 to the present day, the story continues with important achievements in the aqueduct, energy and construction sectors, as well as the routine management of drinking and industrial water withdrawal, supply and distribution services in the Liguria and Tuscany regions.