Most of the grassy banks and walking paths usually visible east of Main St. are obscured in this morning’s footage from semi-regular Allen’s Landing correspondent Christine Wilson, who captured some shots of high water (and a few street lamps shakin’ it in the current). This morning’s heavy rain has overtopped roads in some of the usual spots (check out Transtar’s list of water-related road closureshere) west and north of Downtown, and the National Weather service has just issued a flood warning for parts of the city through 4:15 this afternoon (with more rain expected later today). The confluence of White Oak and Buffalo bayous, receiving much of that water as it runs toward the bay, appears to have been swept clean of trash and baby ducks for the time being, though some larger waterfowl were still spotted hanging around upslope on the southern shore:
COMMENT OF THE DAY: FURTHER READING INTO YOUR HOUSTON FLOOD AND FIRE CHANCES “Every home is susceptible to flooding. There are not ANY non-flood areas. There are only homes that are more likely to flood and homes that are less likely to flood. The likelihood is expressed, on flood maps, by the single-year probability of being flooded (with some other factors). This does not properly describe the likelihood of being flooded during the course of a longer time period — of, say, a 30-year mortgage. Homes eligible for NFIP preferred flood rates can have up to just less than a 1 percent chance of flooding annually. These ‘preferred areas’ are what the public thinks of, euphemistically, as non-flood areas. Assuming a .009 probability (just less than 1 percent), a home has a 20 percent chance of flooding, at least once, over the course of a 30-year mortgage (look up binomial probability). An alternative way to think about it is that 1 in 5 homes, in preferred flood zones, will flood over the course of a 30-year mortgage. [In that case,] you are actually more likely to experience a flood than a house fire in a ‘preferred flood area.'” [Jardinero1, commenting on Where Houston Floods Outside the Flood Zones] Image of recent flood map revisions: FEMA RiskMap6
From some of the same folks who brought you those fun-with-worst-case-scenarios hurricane flood maps earlier this year — Neena Satija and Kiah Collier of the Texas Tribune, and Al Shaw of ProPublica — comes a fresh set of animated maps of a few of Harris County’s most flooded and floodable places, along with a bit of investigation into how they got that way (and whether that might change any time soon). The new illustrated presentation shows off the spread of properties that took a dip during some of Harris County’s last few citywide submersion events (flooded properties from Tax Day 2016 are shown in yellow above, along with the Memorial Day 2015 flooded properties in orange).
Texas A&M Galveston researcher Sam Brody tells the authors that “more people die here than anywhere else from floods. More property per capita is lost here. And the problem’s getting worse.” In sorting through some of the whos, whats, and hows of Harris County’s flood infrastructure and chronically soggy residents, the article juxtaposes the recent flood damage data with the likes of FEMA-mapped 100- and 500-year flood zones (shown above), a visual tally of the land area developed last decade, and a view of what’s left of Houston’s coastal prairie (as of 2010):
The areas in red above mark some of the new additions to the legally-gotta-buy-flood-insurance zones on FEMA’s recently revised flood maps. The agency’s interactive online viewer lets you mix-and-match a few data sets for Harris County (as well as Galveston, Fort Bend, and Wharton), compare the old mapped flood zone boundaries to proposed new ones, or look only at what would change — a FEMA spokesperson told Houston Public Media that about 8,000 properties have been added to the list in Harris County, while only about 400 were dropped.
Those acid-green highlights are areas that have been removed from the special flood hazard zone by the updated map (while blue shows areas that have just changed floodplain classification some other way. Bits of brown and yellow in other areas of the map show places added or removed (respectively) from the floodway. The updates above to the mandatory flood insurance zone (legally called the Special Flood Hazard Area) are set to go into effect in January, as shown above.Buffalo Bayou and its tributaries are pretty marked up:
Residents of the Rio Brazos area near Cumings Rd. north of Rosharon are being advised as of this afternoon to boil their tap water until further notice, while the Fort Bend County Fresh Water Supply District 2 sorts out possible problems stemming from a flood-related loss of water pressure in the network. (The map included here has been added to the Fort Bend County emergency office’s Facebook page following a brief online outpouring of confusion as to what neighborhoods the warning was actually targeting.)
Meanwhile, TXDOT is still listing dozens of miles of roadways as covered by to high water as of this morning, with more closures expected as Brazos floodwaters drain southwest toward Angleton and Freeport. Here’s Brazoria County’s latest worst case scenario potential floodmap, with the county’s mandatory evacuation zones now stretching across more than 15 miles from roughly Brazos Bend State Park to the outskirts of Angleton:
COMMENT OF THE DAY: WHY FLOOD CONTROL ENTHUSIASTS KEEP EYEING PREVIOUSLY PAVED LOTS “This is a standard practice: to elevate [existing] commercial properties so they will drain off the property. It is very easy to do. The concern is that the city of Houston does not require new properties on old lots to detain water on the lot. . . . Elevated commercial properties that do not mitigate acre-foot-for-acre-foot will lead to water running off and flooding adjacent properties. It is a simple concept, but developer propaganda is strong. The most common myth promulgated by the developers is that if something was already concrete then a new property need not mitigate run-off. The fact is, any time a new development is built that does not mitigate run-off, it will force water onto its neighbor. [Flooding, commenting on Former Fiesta Site Preps for Teardown as Heights Dry Zone Petitioners Circle] Illustration: Lulu