Groundwater Reduction Plan | HARRIS COUNTY WATER

🌊 City of Houston Groundwater Reduction Plan

Working Together to Protect Our Water Supply in Area 3

🚰 What Is the Groundwater Reduction Plan (GRP)?

The Groundwater Reduction Plan, or GRP, is a big project led by Harris-Galveston Subsidence District (HGSD) to protect our underground water supply.

Over the years, using too much water from underground (called groundwater) has caused the ground to sink in some areas. This is called land subsidence. When the land sinks, it can damage homes, roads, and even cause flooding. The GRP is helping stop that by switching to surface water (from lakes and rivers) instead of using groundwater.

🗺️ Who Is Involved?

This project focuses on Regulatory Area 3, part of the Harris-Galveston Coastal Subsidence District (HGSD).

Key partners:

The City of Houston – the main GRP Manager
Local Water Districts – including Harris County WCID No. 74 and many others

Even if some districts don’t directly get surface water, they’re still part of the GRP and working together to meet water use goals.

📘 Why Is Groundwater Regulated in Harris and Galveston Counties?

It all started back in 1918, when cracks were seen in the ground in the Houston area. Scientists began to study why the land was sinking. By the 1940s, they discovered that pumping too much groundwater was the cause.

This sinking, or subsidence, happens when too much water is pulled from underground for a long time. It has caused:

Damage to roads and bridges
Problems with building foundations and pipes
Changes to drainage systems
More flooding, especially during big storms

As Houston grew, so did the need for water. The easiest source at the time was groundwater. But using too much caused huge drops in water levels and damage to underground aquifers.

In 1975, the Texas Legislature created the Harris-Galveston Subsidence District (HGSD) to regulate groundwater use and stop subsidence. Since then, HGSD has become a leader in water conservation and has helped reduce subsidence by creating smart plans and working with local water providers.

📊 How Has HGSD Helped Reduce Subsidence?

HGSD created a regulatory plan based on the best data available. They worked with experts and divided the area into three zones, each with its own groundwater use goals:

Area 1: Only 10% of water can come from groundwater
Area 2: Only 20% can come from groundwater (with some conditions)
Area 3: Also 20%, but with extra steps for permit holders

In Area 3, permit holders must:

By 2025: reduce groundwater use to 40% of total water demand
By 2035: reduce it even more, to just 20%

Studies from universities like the University of Houston show that areas with less groundwater use have lower rates of sinking land.

🛠️ District 74’s Plan: Full Conversion by 2026

To help meet these goals, District 74 has a contract with the City of Houston to fully switch from groundwater to surface water by February 2026.

💧 Why it matters:

Protects our land and homes
Supports growth in the community
Improves water quality and reliability

💰 Estimated Cost: $6 million

This important investment ensures we stay in compliance and secure safe water for future generations.

🎯 What's the Overall Goal?

The main goal is to protect our land and water by reducing how much groundwater we use. Here's the plan for Area 3:

Year Groundwater Use Limit

2025 40% of total water use

2035 20% of total water use

🔍 Why Does This Matter to You?

Houston is growing fast, and with more people comes more water use. If we keep using too much groundwater, we risk flooding, property damage, and long-term water problems. Working together through the GRP protects our community now and for the future.

📌 Key Takeaways

Too much groundwater use makes land sink (subsidence)
Houston is switching to more surface water to prevent this
The Harris-Galveston Subsidence District regulates water use
District 74 is investing $6 million to fully switch by 2026
The plan works—subsidence is slowing where it's been followed

🎥 [Watch Subsidence Video: 1906–2022]