Water Management: Conservation, Quality, and Sustainable Solutions

Understanding Earth's Water Resources

• Approximately 71% of the Earth’s surface is covered by water.
• 97.5% of this water is salt water.
• 2.5% of Earth’s water is freshwater.
• 70% of freshwater is locked up in glaciers and ice caps.
• Only 0.3% of the Earth's total water is accessible for human and animal use through rivers, lakes, and underground aquifers.

The Hydrologic Cycle

The hydrologic cycle is powered by solar energy.

• Evaporation and Transpiration: Move water into the atmosphere.
• Condensation: Forms clouds.
• Precipitation: Returns water to the ground (rain, snow, etc.).
• Runoff: Brings water back into streams, rivers, lakes, and oceans.

Water Usage Statistics

• USA (Drinking): 13 gallons (50 liters) per person.

Typical Daily Supply Needs:

• USA: 115 to 182 gallons (435 to 689 liters) per person.
• Europe: 50 to 150 liters per person.

Historical Water Consumption:

In the past:

• Imperial Rome: Approximately 38 gallons per capita per day (gpcd) (~ 144 liters per capita per day (L/cd)).
• London, 1912: Approximately 40 gpcd (~ 151 L/cd).
• American Cities Before WWII: Approximately 150 gpcd (~ 568 L/cd).
• Los Angeles, Mid-1970s: Approximately 180 gpcd (~ 681 L/cd).

Water Reduction Strategies

Parametric and AI-Assisted Building Information Modeling (BIM) for Water Management

• Provides a comprehensive framework for designing, constructing, and operating sustainable and water-efficient buildings.
• Supports simulation, analysis, and optimization of water systems for reduced consumption and efficient distribution.
• Enables real-time monitoring, predictive maintenance, and integration with sustainability frameworks such as LEED.

Water Quality in Buildings

Pollutants and Indicators in Drinking Water

Free Water Surface (FWS) Wetlands

• Water is exposed to the atmosphere.
• Vegetation grows in standing water or saturated soil.
• Aesthetic, marsh-like appearance.

Subsurface Flow (SSF) Wetlands

• Water flows below the surface through gravel or soil.
• Provides higher treatment performance in smaller areas.
• Less visual exposure of water.

Integrated Water Resource Management (IWRM) for Water Scarcity

• A comprehensive planning method in architecture and urban design to address water scarcity.

Wetland Treatment Time Calculation:

To find out how many hours it would take for the wetland to treat 12,000 cubic meters of wastewater at an average flow rate of 30 cubic meters per hour, use the formula:

Time = Total Volume / Flow Rate

Step 1: Insert the given values into the formula:

Time = (12,000 m3) / (30 m3/hr)

Step 2: Perform the calculation:

Time = 400 hours

Phytoremediation: Uses plants in bioswales and vegetated strips to treat and clean stormwater runoff, polluted water, the air, and the soil before it re-enters the ecosystem.

Drainage Systems for Stormwater

• Use waterproofing, head walls, footings, and perforated footing drains to direct stormwater away from structures.
• Prevent hydrostatic pressure buildup in hillside and sloped buildings.

Uniform Plumbing Code (UPC) Standards

• The Uniform Plumbing Code (UPC) is a set of regulations developed by the International Association of Plumbing and Mechanical Officials (IAPMO) to govern the installation and inspection of plumbing systems. It ensures public health and safety, water conservation, and efficient design of plumbing infrastructure.
• Vertical piping is sized based on pipes flowing 1/24 full.
• Rectangular pipes must have equal cross-sectional area to round pipes and maintain a side dimension ratio not exceeding 3:1.

pH and Water Quality

• Neutral pH: 7
• Acidic water: pH < 7 (corrosive)
• Alkaline water: pH > 7

Water Hardness

• Temporary hardness: Caused by bicarbonates, removable by heating.
• Permanent hardness: Caused by sulfates, chlorides, and nitrates; requires chemical treatment.

Connecting properties to centralized sewer systems is the most effective long-term solution to the threat of leaking septic tanks contaminating aquifers.

Solar Heating & Cooling (SHC) Systems

Advantages

• Displace the need for electricity or natural gas.
• Provide sustainable heating and cooling for domestic hot water (DHW) and space heating. Using higher water supply temperatures in domestic hot water (DHW) systems reduces the risk of Legionella pneumophila bacteria growth, which thrives in lukewarm water conditions.
• Combined systems save floor space and equipment costs by integrating DHW and space heating.

Living Machines and Constructed Wetlands

• Living Machines: Ecological systems that use tanks with live plants, animals, and microorganisms to treat wastewater and purify air.
• Constructed wetlands offer low construction cost, and low-maintenance wastewater treatment alternatives to traditional systems.

Living Shorelines for Coastal Resilience

• Stabilize shorelines using plants, sand, and rock to reduce erosion and protect against sea level rise and storm surges.
• Enhance coastal ecosystems and support marine habitats.

Maximum pressure at the bottom of the zone: 80 psi (552 kPa).