Ship scuba diving in Freetown

Freetown's Queen Elizabeth II Deep Water Quay (8°29'38.81"N, 13°12'57.58"W) is in a tidal river estuary that flows at up to 6 knots except at slack water. Since our arrival here a week ago, our cooling water intakes have been constantly choked by garbage. The current makes it almost impossible to dive under the Africa Mercy for 22 out of 24 hours a day, so every time we dive now, we need to be accompanied by a rescue boat to stop us being swept away. Micah and I managed one semi-successful dive on Thursday when the tide was coming in but visibility was limited and we found only 2 out of 4 intakes. But today we had a disastrous dive as the tide was going out - the engineers called us to say every single intake was blocked, but two attempts and an hour later we still hadn't managed to dive - we were repeatedly swept away every time we left the rescue boat, plus we had to contend with delays caused by two big ship movements from neighbouring berths. We returned to our cabins utterly exhausted from hauling ourselves in and out of the rescue boat and trying to swim against the current. Slack water will be around 3pm this afternoon, so we'll have another go then when hopefully I'll have regained some of my strength...Olly