River Whitewater facts for kids

Quick facts for kids Whitewater
Greywell Mill on the upper reaches of the River Whitewater
Country	England
Counties	Hampshire
Physical characteristics
Main source	Bidden 51°14′15″N 0°59′14″W / 51.2376°N 0.9871°W / 51.2376; -0.9871
River mouth	River Blackwater South-east of Swallowfield 51°21′59″N 0°56′10″W / 51.3663°N 0.9361°W / 51.3663; -0.9361
Length	12.2 mi (19.6 km)
Basin features
Tributaries	Right: River Hart

The River Whitewater is a beautiful river in Hampshire, England. It starts from springs near Bidden Grange Farm. The river then flows northeast. It eventually joins the River Blackwater near Swallowfield.

The water in the upper part of the river flows over chalk. This helps keep the water clean. Because it's so clean, the River Whitewater is home to lots of different plants and animals. People have known about this river for a long time. It was even shown on a map of Hampshire made in 1646!

Many towns and villages are located along the River Whitewater. These include Greywell, North Warnborough, Hook, Hartley Wintney, and Heckfield. The river is a great place for fishing. It has many types of fish. However, some non-native animals like mink and signal crayfish also live here.

Where the River Flows

The Whitewater begins as many small springs and channels. These are found near Bidden in a special natural area. This area is called the Odiham Fen Site of Special Scientific Interest (SSSI). The water comes from underground chalk. This water helps unique plants like lesser tussock-sedge grow.

Soon, these small channels form a pond called Mill Head. This pond was once used for Greywell Mill. The old mill building and its house are very old. They are protected as a historic structure. More springs join the river as it flows northeast.

Near Deptford Bridge, you can find the entrance to Greywell Tunnel. This tunnel was built in 1792 for the Basingstoke Canal. It's about 1,230-yard (1,120 m) long. The tunnel is not used anymore. This is because part of its roof fell in. Also, many bats now live inside it. The M3 motorway was built over the tunnel's path.

Further along, you'll see Greywell Pumping Station. This station takes water from the chalk underground. It has been providing drinking water since the early 1900s.

The Basingstoke Canal crosses over the river on a special bridge called an aqueduct. The river then flows around Odiham Castle. This castle was built a long time ago, between 1207 and 1212. Only a small part of the castle remains today. The land around the castle is also a protected historic site.

Near the castle, there was once a mill called Castle Mill. Then, you reach Warnborough Mill at Warnborough Green. This mill building is from the 18th century. It used to grind grain. Now, it has been turned into a restaurant.

As the river continues, it goes under several roads. These include the B3499 Hook Road and the A287 road. You will also see more weirs. Weirs are small dams that control water flow. The river flows past Lodge Farm, which has a very old timber-framed house from the 15th century. There is also a site where a Roman villa once stood.

Next, you'll find Poland Mill. This is a large building from the 18th century. It once had six water wheels! Only one of these wheels remains today.

The river then turns north. It passes under the M3 motorway, the South Western main line railway, and the A30 road. These crossings are east of Hook. Beyond them is Hook Mill. This mill building is from the 17th and 18th centuries. It is now part of a private home. You can still see the huge wooden beams inside.

At the small village of Dipley, a road crosses the river at Dipley Bridge. After that is Dipley Mill. This building is mostly from the 18th century. After Mattingley Clappers Bridge, the river flows through a long countryside area. A stream from Highfield Park joins the river here. The next road crossing is the B3011 road near Hazeley.

The main river that flows into the Whitewater is the River Hart. It joins the Whitewater on the right side. The combined rivers then flow under Heckfield Bridge. This bridge was built in the mid-19th century. Riseley Mill is the last mill on the river. It is the tallest mill building on the river, with four floors. Finally, the Whitewater joins the Blackwater River.

Wildlife and the River

The upper part of the Whitewater is a special type of river called a chalk stream. Its water comes from underground chalk. This makes the water very clear. It also keeps the water flow steady. As the river gets closer to Hook, the ground changes. It becomes more clay and gravel. Here, the water flow is less steady. The river banks are steeper, and the water can look a bit cloudy.

The river's health is important. Fish find it hard to move upstream because of the many weirs. These weirs were built for mills long ago. They break up the fish's natural habitat. The river has many types of fish. These include brown trout, barbel, chub, dace, perch, pike, and roach. People enjoy fishing along most of the river.

Some parts of the river are used for trout fishing. Here, more trout are added from hatcheries. Experts have studied the river. They found that the water flow seemed to be getting lower. Also, the growth of aquatic plants was decreasing. Fewer plants mean fewer insects for trout to eat.

One problem is that Dipley Mill creates a long section of deep, slow-moving water. This is not good for trout. Also, large Alder trees on the banks block sunlight. Trout need some shade, but too much shade stops plants from growing. Cutting back some trees would help plants grow better.

Water also leaks through the river banks in some places. This happens because the banks were raised for milling in the past. This leaking can damage the banks. An invasive animal, the North American signal crayfish, makes this worse. They dig burrows into the banks, causing more erosion.

Some low weirs were built to raise water levels. But they caused slow water. This made fine silt build up behind them. Experts suggest removing some weirs. They recommend adding large pieces of wood to the river edges instead. This would create faster water. It would also help clean silt from the riverbed. This would be better for plants, insects, and fish like trout. Further upstream, you can see water-crowfoot growing. This plant needs a gravel riverbed and fast water. It is a typical chalk stream plant. It provides important homes for river insects.

How Healthy is the Water?

The Environment Agency checks the water quality of rivers in England. They give each river an overall health rating. This rating can be high, good, moderate, poor, or bad. They look at several things to decide this.

One part is the biological status. This checks the types and numbers of invertebrates (like insects), flowering plants, and fish. Another part is the chemical status. This checks if there are too many chemicals in the water. Chemical status is rated as good or fail.

In 2019, the water quality of the Whitewater was as follows:

The river's quality is not as good as it could be for a few reasons. These include:

• Water released from sewage treatment plants.
• Runoff from farms.
• Physical barriers like weirs. These stop fish and other animals from moving freely.
• The presence of the North American signal crayfish. This is an invasive species.

Even though the river has many invertebrates and aquatic plants, the barriers for fish movement make the overall health rating poor.

Mills Along the River

There is clear evidence of eight water mills along the River Whitewater. All of them were used to grind corn in 1883. Old maps show some of these mills. For example, a map from 1759 shows Paper Mill, Poland Mill, and Warnborough Mill.

Greywell Mill has been on its site since at least 1600. The current building is from the 18th century. It had a wooden waterwheel that powered two grinding stones. Some of the old machinery is still there. The mill stopped working in 1932. This was because the owner thought fishing was better when the mill wasn't running!

When the Domesday Book was written in 1086, there were eight water mills listed in Odiham. Some of these mills were owned by Robert the Parker. King John took some of Robert's land to build Odiham Castle. The king even burned Robert's mills! Warnborough Mill was destroyed by a fire in 1337-38. But it was rebuilt in 1345-46.

The river above Castle Mill was built up with banks. The mill itself burned down in 1910 and was not rebuilt. It was a large fulling mill. This type of mill was used to make woollen cloth. After the fire, the mill house was rebuilt in the 1920s.

Warnborough Mill became known as King's Mill. This was because Odiham was a Royal Manor. The mill was owned by the Lords of the Manor until 1920. The last person to use it to grind corn was Sydney Loader in 1895. Around 1904, the machinery was removed. The building became a private house. In the 1990s, it was turned into the Mill House Restaurant. The mill wheel was restored in 1995 and again in 2011. There is a small 3.5-foot (1.1 m) waterwheel in the garden. It might have been used to make electricity.

Poland Mill is named after an old manor called Polling. The current building is from the 18th century. It once had six water wheels! Today, a room on the ground floor still has some mill wheels.

The area of Newnham once had two corn mills and a paper mill. One of these mills was probably Hook Mill on the Whitewater. The Paper Mill was on the Whitewater below Wolson Bridge. This is now the Crooked Billet Bridge on the A30 road. The first mention of a paper maker in the area was in 1749. When it stopped making paper, it became a corn mill known as Hook Mill. The current building is from the 17th and 18th centuries. It is now part of a private home.

Dipley Mill was a three-story building made of red bricks. It probably had four pairs of grinding stones and two water wheels. This mill was mentioned in the Domesday Book. In the 19th century, a second water wheel was added. But the building would shake when both wheels worked together! Milling continued until 1927. Then, the building was turned into a country house.

Heckfield also had a mill when the Domesday Book was made in 1086. A survey in 1341 listed two mills: one at Holdshott and one at Mattingley. The mill at Mattingley was demolished in the late 19th century.

Riseley Mill is the last mill on the river. The current building is from the late 18th century. It was originally powered by a large wooden water wheel. In 1910, a new iron waterwheel was too small and never used. An oil engine was later used to power the machinery. During the Second World War, all the machinery was removed. The mill was used as a pill-box, a small, strong fort. It might have also been a bakery. A huge baker's oven was found in a shed in 1966. The mill building and house were sold in 1968 and became private homes. A fire in 1991 badly damaged the roof, which had to be replaced.