Why the Need?
Think of our community’s sewer system like a busy intersection. During heavy rain, stormwater surges through the pipes similar to how cars create a traffic jam during rush hour. This can overwhelm even the most robust sewer systems, causing overflows and polluting waterways. Equalization (EQ) tanks are a vital part of SD1’s Clean H2O40 sewer overflow mitigation program.
What is an Equalization Tank?
An EQ tank is a large above-ground or underground storage tank designed to collect stormwater during heavy rain events. It slowly releases the flow of water back into the system once capacity becomes available. EQ tanks are typically only full a few days each year during extreme weather conditions.
How Does It Work?
Equipped with flow meters, EQ tanks act like smart traffic lights for water. When the flow becomes too heavy, the flow meters signal the system to divert excess water into an EQ tank. The tanks serve as temporary storage reservoirs, preventing the system from becoming overloaded, which results in sewer overflows.
Just like traffic lights return traffic to normal flow after rush hour, the EQ tanks gradually release stored water back into the system once the storm subsides. This controlled release ensures that the treatment plant can handle the flow efficiently, keeping our waterways clean.
Local Projects Making a Difference
SD1 currently operates three large above-ground EQ tanks, which collectively reduce 27 million gallons of typical-year sanitary sewer overflows into our region's neighborhoods and waterways. Moving forward, SD1 is committed to continuing its use of innovative strategies to improve water quality and enhance the quality of life for all residents in our community.
EQ Tank Fun Facts:
Highland Heights EQ Tank
- Height: 39.5 feet
- Capacity: 1.4 million gallons
Silver Grove EQ Tank
- Height: 35 feet
- Capacity: 1.6 million gallons
Wilder EQ Tank
- Height: 61 feet
- Capacity: 7.3 million gallons