Loch Eck joined the 10th Escort Group in the Western Approaches in December 1944 for anti-submarine patrols and support for convoy escorts. In January 1945 the Group was transferred to Scapa Flow for anti-submarine operations in the Faeroes - Iceland Gap. On 3 February she sank the north-west of Shetland with her Squid (mortar) after Hedgehog (mortar) attacks by the frigates and . On 14 February she took part in the sinking of, and on the 17 February of in the same area.[1]
In March the Group was redeployed in the English Channel and South-Western Approaches as "Force 38". In April Loch Eck carried out trials of new sonobuoy submarine detection equipment. On 23 May the ship was attached to Rosyth Command to support "Operation Doomsday", the reoccupation of Norway. On 1 June she escorted from Kristiansund to Loch Eriboll as part of "Operation Deadlight", returning to Norway on 6 June as part of the escort for Convoy RN1 taking King Haakon VII of Norway to Oslo.[1]
After a refit at the Charles Hill & Sons shipyard in Bristol in June and July, she sailed for the Indian Ocean in August, to join the East Indies Escort Force. There she carried out Guard ship and military support duties, as well as the repatriation of military and civilian personnel. She was also present at the formal Japanese surrender of Bali in February 1946 and at Lombok in March. She sailed for home in May, but her return to the UK was delayed after a collision in Colombo with a Navy cutter. She returned to Devonport to decommission on 13 August 1946.[1]
Loch Ech was one of six Loch-class frigates sold to the Royal New Zealand Navy. Renamed HMNZS Hawea, she was acquired on 7 September 1948, and commissioned on 1 October 1948.[2]
Since the Admiralty named the Loch-class ships after Scottish lakes, the six in New Zealand service were renamed after New Zealand lakes. Lake Hāwea is a glacial lake located in the Central Otago region of New Zealand. The name is Māori and is thought to refer to a local tribe although the exact meaning is uncertain. Hawea was the first of three ships with this name to serve in the Royal New Zealand Navy.
After commissioning at Devonport Hawea sailed for the Mediterranean with three other Loch-class frigates. After exercises with the Mediterranean Fleet in November, she sailed for Auckland, via the Suez Canal and Indian Ocean, arriving in January 1949 to join the 11th Frigate Flotilla.[1]
On 22 March 1949 Hawea participated in sinking the coal hulk Occident in Palliser Bay.
In 1949 Hawea carried out patrols in the Pacific, visiting Suva, Fiji and Samoa. After a refit from October to February 1950 she was transferred on loan to 2nd Frigate Flotilla of the Mediterranean Fleet, with her sister ship joining the flotilla at Malta in May for Fleet exercises and cruises. She returned to Auckland in November.[1]
The Korean War started on 25 June 1950 when North Korean forces crossed the 38°N parallel and invaded South Korea. The New Zealand Government decided to maintain two frigates in support of a United Nations Naval Force assisting South Korea. Haweas sister ships, and, were hurriedly prepared for war service and sailed for Sasebo, their main base in Japan, on 3 July 1950. They did escort and patrol services, often working with Commonwealth, South Korean and other Allied ships, and in support of amphibious landings. The frigates were rotated in turn with the other four Loch frigates.
In February 1951 Hawea sailed to Kure, Japan, to join the United Nations Task Force. On 18 May she shelled a gun position on the coast, the first time that an RNZN ship fired on the enemy. From June to December she provided navigational data for bombardments in the Han River estuary, shelling rail traffic and maintaining a blockade.[1] On 15 September 1951, Hawea swamped a 7.6m (24.9feet) motor boat which sank in the Han River estuary while navigating swift tidal channels to reach a bombardment position.
In February 1952 she was relieved by, returning to Auckland on 8 March. She had spent 272 days at sea, steamed 55,000 miles, and fired 21,000 rounds of ammunition. After refit and maintenance at Auckland from April to June she returned to Korea in October for further operations. After the Armistice Agreement of July 1953 she returned to Auckland, arriving there in August.[1]
After a refit she returned to the 11th Frigate Flotilla in February 1954 for patrols and port visits. In December 1956 she and Pukaki escorted the supply ship in a passage to the Southern Ocean, sailing from Bluff to the edge of the pack ice.[1]
On 15 February 1957 Hawea was decommissioned and put into reserve. The ship was used as a Harbour Training ship in Auckland until sold for breaking up in September 1965.[1] On 15 November 1965 Hawea and sister ship Pukaki were towed by the tug Atlas to a breaker's yard in Hong Kong.