Can you feel the ocean's tides in Pennsylvania? You can at Neshaminy. Waves won't knock you down, but if you watch the river, you'll see it rise or fall a foot an hour. Even though the river flows another 116 miles from here to the ocean, you're at sea level. When the tide comes in at a New Jersey beach, the water rises here also. Because tides affect this part of the river, it's called an estuary. You won't find another place in Pennsylvania like this one. The estuary at Neshaminy is fresh water, not salt, unlike the lower estuary. Plants and animals from two worlds meet here - some from the ocean and some from upstream headwaters. Congress thought estuaries like this were so important that it passed the Coastal Zone Management Act. The Act provides money to the Commonwealth to ensure proper management for its coastal resources.Delaware Estuary: Like No Place ElseWe need this estuary. We use it as a river and as a link to the ocean. Philadelphia's drinking water comes from the estuary. The inlet pipe is three miles downstream of here at Torresdale. People boat in the estuary. Marsh wrens, rare elsewhere in the state, eat snails and water insects in the lower estuary. Because early Americans used the river, we find traces that teach us about their lives. People find crabs, shad and occasionally a stray whale in the estuary.