Category: Urban Systems

Conventional Activated Sludge (CAS) Systems

Conventional Activated Sludge (CAS) Systems

Conventional Activated Sludge (CAS) Systems

04/10/25

“How can we filter wastewater using air and bacteria?”

Conventional Activated Sludge (CAS) Systems are a cornerstone of modern wastewater treatment technology. CAS systems are composed of two tanks, an aeration tank and a settling tank. The CAS process begins with influent wastewater pouring into the aeration tank. The aeration tank aerates (adds air or oxygen) into the wastewater to activate microorganisms already present. These microorganisms break down the organic pollutants into less harmful biomass. Over time, the microbes and the waste will clump together to form flocs. The water and flocs are then transported to the settling tank (also known as a clarifier) where the heavier flocs settle to the bottom as sludge and clear water flows out as effluent. The sludge then leaves the settling tank, where part of it is removed from the CAS (Waste Activated Sludge) while the other portion is returned to the aeration tank (Return Activated Sludge) to provide extra microorganisms to new influent water. The attached image visualizes this process.

Why Used Dishwasher Water is Considered Blackwater

Why Used Dishwasher Water is Considered Blackwater

Why Used Dishwasher Water is Considered Blackwater

04/09/25

“Why is used dishwasher water considered blackwater?”

People usually think of blackwater as fecal-contaminated wastewater. But this is only part of the definition. Blackwater also consists of any wastewater that contains heavy grease. Dishwasher water usually contains heavy grease. This is Why Used Dishwasher Water is Considered Blackwater.

Why Water Towers Don’t Require Electricity for Water Distribution

Why Water Towers Don’t Require Electricity for Water Distribution

Why Water Towers Don’t Require Electricity for Water Distribution

04/07/25

“Why don’t water towers require electricity for water distribution?”

Water towers hold water at elevated distances above ground. They can provide water to anything below using gravitational pressure. This means they don’t require electricity for pumps to provide water. This is Why Water Towers Don’t Require Electricity for Water Distribution.

 Safe Yield Aquifer Discharge

 Safe Yield Aquifer Discharge

 Safe Yield Aquifer Discharge

04/05/25

“What is the point before aquifer discharge becomes unsafe?”

People extract water from aquifers. Taking too much water from aquifers can lead to land subsidence, dry wells, and long-term decline of water yields. The Safe Yield Aquifer Discharge measures the point where aquifer water extraction is sustainable. 

Drainage Maintenance

Drainage Maintenance

Drainage Maintenance

04/04/25

“How do we maintain our drainage systems?”

Drainage systems are essential for keeping water out of places. But over time they become too clogged to properly work. Drainage Maintenance using cleaning, clutter removal, and infrastructure repair can help keep drainage systems alive and well.

Why People Should Not Build Wells Next to Roads

Why People Should Not Build Wells Next to Roads

Why People Should Not Build Wells Next to Roads

04/03/25

“Why should people not build new wells next to roads?”

New wells are built to accommodate water demand. For many infrastructure operators, building a well next to a road is tempting because repair vehicles can service the well more easily. However, this will expose the well to more runoff contamination, polluting the water supply. This is Why People Should Not Build Wells Next to Roads. Many places specify that people can only build wells after a minimum distance from roads.

Using Lakes for Ground Source Heat Pumps

Using Lakes for Ground Source Heat Pumps

Using Lakes for Ground Source Heat Pumps

04/02/25

“How can we use lakes for ground source heat pumps?”

Ground source heat pumps usually store heat deep in the Earth. But if a nearby lake meets the requirements for minimum volume, depth, and water quality, then it can also qualify as a storage material. This is how people can go about Using Lakes for Ground Source Heat Pumps.

How the US Clean Water Act Fines Direct Wastewater Discharges

How the US Clean Water Act Fines Direct Wastewater Discharges

How the US Clean Water Act Fines Direct Wastewater Discharges

04/01/25

“How does the US Clean Water Act fine people who direct discharge into waters and wetlands?”

The US Clean Water Act governs water sanitation in the US. If someone direct discharges wastewater into US waters and wetlands, they can get between 1 – 6 years of convictions and have to pay between $2,500 and upwards of $100,000 per day depending on the severity of the crime committed.

Why People Don’t Like Drinking Iron-Contaminated Water

Why People Don’t Like Drinking Iron-Contaminated Water

Why People Don’t Like Drinking Iron-Contaminated Water

03/29/25

“Why don’t people like drinking iron-contaminated water?”

Drinking water contaminated with higher iron levels does not present a health risk. Instead, it causes a metallic taste, poor smell, a rust color in the water and on surfaces it comes in contact with, and small sedimentation in drinking water containers. This is Why People Don’t Like Drinking Iron-Contaminated Water.

Image credit: http://www.cdn.prod.website-files.com