The present invention provides an acoustic flow meter assembly (2) for pipes or open channels, said assembly including a frame (24) with a predetermined geometry. The frame has at least one user accessible port (36-42) with the at least one user accessible port (36-42) adapted to receive an interchangeable cartridge (44) which contains at least one acoustic transducer (46) to measure fluid velocity through said frame (24).

A self-activating flood barrier includes a chamber (1) having first and second side walls (3, 5), a dam member (9) adapted to self-deploy in the event of a flood to inhibit the passage of water to a region to be protected, and a low-friction device (77, 79) positioned between the dam member and at least one of the first and second side walls of the chamber when the dam member is deployed. The low-friction device prevents jamming between the dam member and the at least one side wall.

A self-activating flood barrier includes a chamber (1) having first and second side walls (3, 5), a dam member (9) adapted to self-deploy in the event of a flood to inhibit the passage of water to a region to be protected, and a low-friction device (77, 79) positioned between the dam member and at least one of the first and second side walls of the chamber when the dam member is deployed. The low-friction device prevents jamming between the dam member and the at least one side wall.

The present invention provides an acoustic flow meter assembly (2) for pipes or open channels, said assembly including a frame (24) with a predetermined geometry. The frame has at least one user accessible port (36-42) with the at least one user accessible port (36-42) adapted to receive an interchangeable cartridge (44) which contains at least one acoustic transducer (46) to measure fluid velocity through said frame (24).

Disclosed is a system for managing water. In example embodiments, the system may include a long pond for storing water. In some embodiments the long pond may be used to prevent flooding, in other examples the long pond may be used as a reservoir for holding water usable with irrigation and sub-irrigation systems.

The present invention provides an acoustic flow meter assembly (2) for pipes or open channels, said assembly including a frame (24) with a predetermined geometry. The frame has at least one user accessible port (36-42) with the at least one user accessible port (36-42) adapted to receive an interchangeable cartridge (44) which contains at least one acoustic transducer (46) to measure fluid velocity through said frame (24).

The present invention provides an acoustic flow meter assembly (2) for pipes or open channels, said assembly including a frame (24) with a predetermined geometry. The frame has at least one user accessible port (36-42) with the at least one user accessible port (36-42) adapted to receive an interchangeable cartridge (44) which contains at least one acoustic transducer (46) to measure fluid velocity through said frame (24).