Yes, the tide effects the Ribble at Church deeps on the higher tides The river can come up by several feet at Church deeps but its not as dramatic as on some rivers. I fish the Ribble around Walton le dale (next section down river) quite a lot and i,ve never been caught out by the river coming up with the tide. You get a reasonable amount of time to move your tackle to higher ground before the water reached its higher levels. If your worried about the tide. Check the tide table before fishing and put a bank stick at the waters edge to show when the water starts to rise.

The tide run off can switch the fish on to the feed for a short time on the very hardest days in winter. Think you might have the Southport card based on where your talking about. If so. Give the Darwen a go after a high tide as the water runs off. Some great fishing to be had when the main river is fishing very hard.