6/11/26 – Those seeking to understand flooding in the Lake Houston Area need to understand the placement and construction of the dam within the larger San Jacinto River Basin. Lake Houston is what hydrologists call a “terminal reservoir.” Flood risk in the Lake Houston area is governed less by any single upstream factor and more […]
4/10/26 – Sediment buildups reduce river conveyance everywhere. But sedimentation is especially threatening in the Lake Houston Area because: Consequences of Sedimentation This combination of factors is not unique, but it is unusual in its magnitude and consequences. Here’s why. There is no way to remove sediment from Lake Houston except by dredging. Texas Water […]
4/9/2026 – Another “lesson learned” about flooding since Hurricane Harvey has been role of sedimentation from industrial-scale sand mining upstream from Lake Houston. It can only be appreciated from the air. Few, if any, urban watersheds have such dense clusters of sand mines directly upstream from their water reservoirs in major river channels. This is […]
4/8/26 – Water extraction from aquifers, driven by population growth, causes subsidence. It is a well-recognized phenomenon across the U.S. and in southeast Texas. Here in the Lake Houston Area, differential subsidence is creating a bowl in the landscape that amplifies flood risk for people in southern Montgomery and northern Harris Counties. Let’s look first […]
Flat terrain is one of the most under-appreciated aspects of flood risk. It complicates virtually every aspect of flood control. Flat terrain increases flood risk primarily by reducing the speed of runoff. It causes water to pool rather than drain away. Also, lack of gradient lets floodwaters spread wider, increases sedimentation, backs water up into storm […]
4/6/26 – One of the biggest “lessons learned” from Harvey is that coordinated Joint Reservoir Operations are crucial. The San Jacinto River Basin has two reservoirs controlled by dams. But coordinating their operation to reduce flooding remains elusive after 53 years. The San Jacinto River Authority (SJRA) finished the Lake Conroe dam in 1973, but […]
4/5/26 – Today’s “lesson learned” from almost nine years of research into flooding is about the counterintuitive “Limitations of Multiple Small Detention Basins at Watershed Scale.” Research shows that hundreds of small ponds built during subdivision construction do little to reduce flooding at the watershed scale and may increase it in places. A 2009 National […]
4/4/26 – States, counties and communities across the U.S. prioritize flood mitigation over flood prevention, despite FEMA studies that have found prevention costs up to 5-6X less than correction. What types of costs? Examples of Mitigation Costs Examples of mitigation costs include: Examples of Prevention Costs/Strategies Examples of much more cost-effective Prevention Strategies include: While […]
4/3/26 – Engineers design infrastructure to handle certain amounts of rainfall. But: Infrastructure bottlenecks reveal themselves during extreme events. This is a universal phenomenon. Bridges, culverts, and channel constrictions control flood elevations behind them. You see this everywhere around the world. It’s a well studied phenomenon. Let’s look at two areas. Appalachia Appalachia has many […]
4/2/2026 – Across the U.S., fragmented governance increases flood risk by creating a patchwork quilt of local interests that makes regulation, compliance and enforcement difficult. One might think that our multi-level system of government – federal, state, county, city, improvement districts, etc. – creates defense in depth. In reality, each governmental entity plays by its […]