As existing water pipe networks degrade with age and require refurbishment, it is becoming necessary to monitor the quality of water flowing through these pipes. Water companies are interested in measuring a variety of parameters, such as colour, turbidity, flow rate, and chlorine levels.

Currently it is necessary to take a sample from the pipe and have it analysed in a laboratory. It is preferable, from both a cost and time perspective, to conduct the analysis in-line. However, access to water pipes which are buried several feet underground is difficult.

It is known to install a flow meter in-line in underground water pipes.

Figure 1 shows a flow meter 10 installed in a water pipe 5. The pipe is situated in a hole 1 approximately one meter below the ground. Water flows through the pipe in the direction of arrows 2. A stopcock 7 is located immediately prior to the point where the flow meter is inserted in the pipe.

The stopcock can be used to stop the flow of water through the pipe in order for the flow meter to be inserted or replaced. The flow meter is inserted by screwing the flow meter into a suitable aperture 9 located in the pipe. The stopcock is then opened and water flow resumes. The entire apparatus is located within an area defined by a baseplate 3 located at the bottom of the hole. The apparatus shown is figure 1 is usually located prior to the water pipe entering a domestic or industrial site.

It is often desirable to install a plurality of further sensors proximate the flow meter to monitor the various water parameters as discussed above. A technical problem exists in that the space around the flow meter is confined.

It is an object of the present invention to provide apparatus which measures of a plurality of water parameters in-line in a water pipe. It is a further object of the present invention that the apparatus measure the water parameters within the confines of the limited space available. The apparatus must be capable of being installed in water pipe with a single hand.

According to the present invention there is provided apparatus for measuring at least one parameter of a liquid sample, said apparatus comprising a tube arranged to be removably attached to a pipe; and a manifold block comprising a central aperture through which said tube is inserted and at least one further aperture to which at least one sensor is removably attached; said tube and said manifold block being arranged such that upon insertion of said tube through said central aperture of said manifold block and attachment to said pipe said manifold block is secured to said pipe in such a manner that said liquid sample flowing through said pipe is able to flow from said pipe via said tube to said at least one sensor and back to said pipe, thereby enabling measurement of said at least one parameter.

A plurality of further apertures may be provided in the manifold block to which a plurality of further sensors may be removably attached The tube may be further arranged such that a sensor can be removably attached to one end thereof.

The sensors may be connected to an external communication means such that they can be read from a remote location. Alternatively, the sensors can be read online via a computer network. Advantageously, remote handling

of the sensors eliminates the need for an operator to visit the site and manually read the sensors.

The manifold block and tube are preferably made of plastic. The plastic may be acetal co-polymer. Alternatively, the manifold block and tube may be made of metal. The metal may be stainless steel or brass.

The tube may be configured in a manner such that the tube comprises an inner and outer cavity. The outer cavity may be formed by a plurality of holes in the enlarged ends of the tube and the inner cavity may be formed by a central opening in the tube, such that water flows from the water pipe through the plurality of holes and returns to the water pipe via the central opening.

The position of the sensors and thus the manifold block is critical in order for the apparatus to fit within the confined space available. Given the confined space in which to operate, the manifold will only fit in one way and must be secured in that position. The present invention enables such an operation to be completed easily and with one hand.

The apparatus can be used to monitor the quality of a domestic water supply, such as a potable water supply. Alternatively, the apparatus can be used to monitor the quality of an industrial water supply. Advantageously, the present invention allows for a plurality of water parameters to be measure in- line with a water pipe. The manifold block can be stacked on top of another manifold block to provide for further sensors to be installed on the water pipe.

The number of sensor apertures on the manifold block can vary according to the number of parameters which need to be monitored. The sensors can be read manually, or remotely.

Advantageously, the arrangement of the manifold block and the elongated tube are such that it enables the manifold to be positioned in a

predetermined location with respect to the pipe and locked down with a single hand.

As will be appreciated any number of apertures can be disposed on the manifold block for the purpose of adding further sensors. The aperture can be located on the sides or the top of the manifold block.

While the principle advantages and features of the invention have been described above, a greater understanding and appreciation of the invention may be obtained by referring to the drawings and detailed description of the preferred embodiment, presented by way of example only, in which:- Figure 1 illustrates the installation of a flow meter in underground water pipes; Figure 2 is a side elevation of the manifold block; Figure 3 is an alternative side elevation of the manifold block; Figure 4 is a cross sectional view of the manifold block; Figure 5 is a side elevation of the tube; Figure 6 is a side view of the tube; Figure 7 is a cross sectional view of the tube; Figure 8 is a plane view of the tube; and Figure 9 is a diagram of the apparatus inserted in a water pipe with a sensor attached to one end of the tube and two further sensors attached to the manifold block.

In Figures 2-4 the manifold block 20 is shown from a variety of perspectives. The manifold block includes a central aperture 22 through which the tube is inserted. The manifold block also includes two further apertures 24,26 to which sensors can be attached. As will be appreciated, the location and number of further apertures can be varied without departing from

the scope of the present invention. For example, the manifold block could be more symmetrically shaped and have two further apertures on opposite sides.

The manifold block is preferably made of a plastic material such as acetal co- polymer. However, the manifold block could be made of other suitable materials, such as metal. The metal could be stainless steel or brass.

In Figures 5-8 the tube 30 is shown from a variety of perspectives.

The tube includes an inner central cavity 32 and a plurality of holes 34 in the enlarged ends of the tube. The holes 34 form the outer cavity. The cavities are arranged such that water flows from the pipe 5 through the outer cavity holes 34 to the sensors and then returns via the inner central cavity 32 to the pipe. Advantageously, the arrangement of the holes 34 adds mechanical strength to the tube.

As will be appreciated the tube may be extended so as to enable insertion through a larger manifold block then is shown in Figures 2-4. The tube is preferably made of a plastic material such as acetal co-polymer.

However, the tube could be made of other suitable materials, such as metal.

The metal could by stainless steel or brass. The tube is preferably threaded at one end to facilitate attachment to the water pipe.

In Figure 9, where parts also appearing in Figures 1-8 bear identical numerals, the apparatus 50 is shown inserted into a water pipe 5. Two sensors 42 and 44 are inserted into apertures 24 and 26 of the manifold block 20. A flow meter 10 is attached to the tube 30 which is inserted through the central aperture 22 of the manifold block. The tube is attached to the pipe is such a manner as to establish water tight seals between the manifold block and the pipe and the tube. Electrical and communication means 48 are attached to the

sensors 42,44 by cables 45,46. The electrical and communication means may be located remotely from the apparatus 50 by using longer cables.

As will be appreciated, the sensors 42,44 can be any one of a number of sensor types used in monitoring water quality. For example, the sensors can measure temperature, flow rate, turbidity, chlorine levels, or colour. The sensors can be permanently attached to the manifold block or can be removably attached so as to allow for different sensors to be installed depending upon the application or for sensor maintenance.

It is not intended that the present invention be limited to the above embodiment and other modifications and variations are envisaged within the scope of the claims.