River Tees

River Tees

1. Location

   • North East of England
   • Drainage basin is 710 square miles
   • Flows in an easterly direction from the Pennines
     • Along the boundary of Yorkshire and Durham until it reaches the North Sea 70 miles later

2. Upper course

   • River flows over hard, impermeable rocks
   • Valley has steep sides forming a v-shape
     • River channel is shallow and rocky
     • River is turbulent and clear
   • High force waterfall
     • And gorges, rapids and potholes
   • Erosion downwards us the main work of the river in the upper course

3. Middle course

   • Gradient becomes less steep
   • Lateral erosion begins to take place and the river begins to deposit sand and gravel
   • River gets wider, river valley gets wider and meanders begins to form

4. Lower course

   • Close to Yarm, very large meanders
   • Very wide estuary with mudflats and sandbanks
   • Estuary has been a magnet for the industry with iron and steel
     • Engineering and chemical works along its length
     • Parts of the estuary are important sites for wildlife
       • Seals and migratory birds

5. Why does it need to be managed?

   • A flashy river
     • Rises on the slopes of Cross Fell at 893 metres
     • Area receives over 2,000 millimetres of rain each year
     • Rainfall reaches the river quickly because the slopes are steep
     • After heavy rainfall or when the snow melts quickly in the spring, the river level can rise quickly and the water also flows downstream quickly
       • This can cause the ‘Tees roll’ or ‘Tees wave’, when the river level may rise as much as one metre in 15 minutes
   • A densely populated area
     • Towns such as Yarm, Stockton and Middlesbrough
     • Densely populated and large industrial areas
       • ICI Chemical Works
     • Flood damage can can run into hundreds of thousands of pounds
     • A huge demand for water use in homes, industry and agriculture
       • Long history of heavy industry in the region had caused water pollution and the loss of trout and salmon in the river

6. How does human activity decrease flooding?

   • The upper tees basin
     • Nine reservoirs
       • Largest is Cow Green Resevoir
         • Holds 41 million cubes metres of water
     • Reservoirs store water which can then be used in times of low flow to cope with water needs at home, industry and agriculture
       • Reservoirs can be used at times with heavy rainfall to store water to prevent flooding
   • The lower tees basin
     • Improved flood warning systems
     • New developments being refused planning permission in low-lying areas
     • Monitoring of river and sea defences
     • Tees Barrage to reduce the risk of flooding by river and the sea
     • Dredging the river to increase channel size and improve navigation
     • From 1810 the river was straightened by cutting through meanders
       • Mandale loop was the first
         • Shortened the river by 4km
       • Quickens the journey to the sea
     • Introduction of floodplain zoning
       • Allows river to flood naturally, reduces need for flood defences, which are expensive and dont last as long
     • Tees Barrage was designed to preserve the environment