Pieter Potter arrived at the Cape of Good Hope in the Nieuw Amsterdam on 24 August 1655, with the rank of midshipman. He was employed on the measurement of Cape lands and making charts from the time of his arrival, probably on the basis of having received some training in navigation. On 17 March 1657 commissioner Ryckloff van Goens* arrived at the Cape to inspect the settlement on behalf of the Dutch East India Company. Potter seems not to have impressed him, for in his report he mentions the difficulty of compiling accurate maps of the country because of the lack of a good land surveyor. From 21 to 26 March Van Goens, probably accompanied by Potter, visited Hout Bay, crossed Constantia Nek and travelled across the flats to False Bay, returned to the vicinity of Rondebosch, and again travelled across the flats between False Bay and Table Bay. At each stopping point he ordered angles to be taken and drawings made. Upon his return to the Fort he ordered that proper charts should be made of the regions visited. This task must have been performed by Potter, for on 28 March his salary was increased and his position as surveyor and cartographer confirmed, with mention of the fact that he had been used as a cartographer by Van Goens. The latter next ordered that beacons be erected in a straight line between Table Bay and False Bay and the distance between the bays accurately determined. This work continued into early April. The resulting line served as a base for the granting of farms to Free Burghers (colonists not in the employ of the Dutch East India Company), and the first farms were measured out at this time.
Upon leaving the colony on 17 April Van Goens left orders for further survey work. This was to be based on the Rhynland foot as the standard of length. However, the unit of length actually employed at the Cape, and probably introduced with Potter's survey work, came to be known as the Cape foot (314.9 mm) and was slightly longer than the Rhynland foot.
Following Van Goens's instructions, during the last days of April Potter and two helpers went to map some of the extremities of the Cape Peninsula that had not yet been visited by the colonists. The next month he requested that a surveyor's chain and other instruments be acquired from the Netherlands. In July 1657 he sailed around the peninsula from Table Bay to False Bay on the Robbejacht and mapped its coastline. Two years later, in July 1659, he sailed on the Schapenjacht to map the coastline from the Cape to Saldanha Bay, including all inlets and their depths, and islands. The method of survey included taking numerous soundings; sketching the outline of land features; pacing off distances along the shore, from the endpoints of which compass bearings were taken to surrounding features; determining the positions of islands by means of such compass bearings, and pacing off their circumference. In October 1659 he was sent further instructions, to proceed overland from Saldanha Bay to St Helena Bay, determine the distance between them, and chart the latter. He reported that St Helena Bay was unprotected except against winds from the south-south-east, and that there was no firewood or fresh water. Saldanha Bay was found to be an excellent anchorage and Potter named one of its inlets Potter's Bay (now Hoedjiesbaai) after himself.
During 1657-1658 he accompanied two expeditions into the interior, sent out by Governor J. van Riebeeck* to locate native inhabitants with whom the colonists could trade for cattle, and to survey routes into the interior. The first, in October 1657, was led by the fiscal, Abraham Gabbema, and travelled past the site of Paarl to the Swartland. They were the first to see and name the Paarl Rocks and to reach and name the Berg River. The second expedition, during February-March 1658, was led by Jan van Hawarden and crossed the Roodezand Pass to a point from where they could see the Tulbach basin, the first colonists to do so. Potter collected useful geographical information, recorded the route travelled, and had been instructed to keep the expedition's diary, though its authorship was officially attributed to Hawarden. Unfortunately one of Potter's compass bearings was in error by 45?, with the result that on several of his charts the course of the Berg River is distorted. On another set of small charts he omitted the scale, with the result that a corrected chart, with its scale, had to be dispatched to the company's headquarters in the Netherlands. Van Riebeeck rightly described this as "negligence of the land surveyor". Van Riebeeck seens to have been dissatisfied with Potter's work, for in February 1759 he sent the fiscal, Abraham Gabbema, with Potter and some men to plot the positions of rocks around the Cape, the fiscal's duty being to ensure that everything was accurately recorded. However, as the first officially appointed surveyor in southern Africa he was a pioneer in his field, and much of his surveying was accurate. Though he did not sign his work, many of the oldest maps of the Cape can be attributed to him.
Potter is mentioned in official documents for the last time in 1661 and probably left the Cape during that year.