That in turn was taken over by Edinburgh Corporation and in 1975, responsibility passed to the Lothian Regional Council, as did the duty to provide sewerage and sewage treatment services.

Alexander Leslie compiled a dosier of photographs, showing the construction of some of the later Victorian reservoirs, which has recently been rediscovered in the archives of Edinburgh Library.

With the population growing rapidly, a major project to divert sewage away from the Water of Leith, the main river through the city, took place in 1864, probably with Napier Bell as the engineer.

[1] There was general disquiet that the supply of water was "extremely deficient both in quantity and quality," and the editor of the Edinburgh Review, Francis Jeffrey, convened a public meeting, at which a committee was formed to take the matter forwards.

This authorised several schemes, including obtaining water from the Crawley springs, some 6 miles (9.7 km) to the south of Edinburgh in the Pentland Hills, an idea that had first been suggested by Thomas Telford in 1811.

[2] James Jardine was appointed as the company's first engineer, who had been involved in the construction of the Union Canal, and who had also been the first person to work out the mean level of the sea.

The water pipeline, which varied in diameter from 15 to 20 inches (38 to 51 cm), was completed in August 1823, and delivered 1,500,000 imperial gallons (6.8 Ml) per day to the city.

Jardine had originally calculated water levels and potential yields from the springs in the Pentland Hills in 1810, while working for Telford.

Millers on the River Esk demanded that water from the Crawley springs should be diverted into the Glencorse Burn, and this was only avoided by paying them an indemnity of between £4,000 and £5,000.

The Company rushed through an Act of Parliament in 1843 to allow them to abstract water from streams at Listonshiels, Bavelaw and Black Springs, all of which are on the north side of the Pentland Hills.

To enable the outlet valve to be inspected or maintained, a sluice made of oak could be lowered in guides, cutting off the incoming water and allowing the pipeline to drain.

[7] Before the two reservoirs had been completed, Leslie could see that they would still not be sufficient to provide the water that Edinburgh needed, and so in 1847 the Company applied for another Act of Parliament.

The three northern reservoirs were designed to store up spring water, so that supplies to the city of Edinburgh could be maintained even if there were future droughts.

The 1847 Act was innovative, in that it contained a clause requiring the company to provide a constant water supply to homes, a concept that had been championed by the sanitary reformer Edwin Chadwick.

[13][11] Prior to the takeover, Leslie had suggested a scheme to exploit the waters of the Moorfoot Hills in 1866 as a way to obtain extra supplies for the people of Edinburgh, Leith and Portobello.

[12] The three burghs had appointed Stewart to look at alternative supplies, and he and Bateman had proposed obtaining water from St Mary's Loch, some 33 miles (53 km) to the south of Edinburgh.

Bateman recognised that this would be more expensive than the Moorfoot Hills scheme, but it had the potential to yield three times as much water in the longer term, and so ultimately would prove to be cheaper.

This was a retrograde step, but may have been influenced by Thomas Hawksley, who had been asked by the Trust to assist Leslie in finding a suitable site.

Trial boring for the Gladhouse Reservoir was thorough, and paid dividends when what was initially thought to be solid rock turned out to be a large boulder.

It consisted on reservoir holding 15 million imperial gallons (68 Ml) of raw water and two slow sand filter settling tanks.

[20] Alexander Leslie collected dozens of photographs, showing the construction of some of the later projects, including the dams and filtration plants, workmen, architects and engineers, which he mounted in a book.

The book was lost from view, but was found in the archives of the Edinburgh Library, and in 2014 the images were compiled to form an online exhibition.

The syphons consist of cast iron pipes which cross valleys, and each is fitted with an automatic valve at the upstream end, which is designed to close if a burst occurs.

A second phase involved pumping water from St Mary's Lock into the Megget Reservoir, and controlling the outflow from the loch by the use of sluices.

The works were phased to ensure that the existing throughput could be maintained during the new construction, and the £8.6-million project took two and a half years to complete from a start date in January 2004.

[36] When there was no effective way of disposing of human waste, those who lived on the upper storeys of Edinburgh's tenement blocks could empty pails and chamber pots into the street below.

[39] The sewer used brickwork sealed with Portland cement and caulked with rope, and was of an egg-shaped section, as pioneered by John Roe, which made them self-cleaning.

[37] This removed much of the threat of water-borne diseases such as cholera from the poorer areas of Edinburgh, and in 1889, a second, deeper interceptor sewer was constructed.

[38] Edinburgh Corporation carried out a feasibility study in 1966, as to how this situation could be improved, and decided to build a new sewage treatment plant on reclaimed land near Leith.

[38] The works initially performed primary treatment only, to remove solids, and the remaining liquid was discharged into the sea through a 1.75-mile (2.8 km) pipeline.