Does West U Flood? The City's Drainage Study, the Watershed, and the Draft Maps

Where does the water go when it rains in West U?

On this page, West U means the City of West University Place; Southampton, Boulevard Oaks and Rice Village sit inside the City of Houston. The drainage system, the ordinance and the construction projects described below are the city's own, and they stop at its line. The Harris County Flood Control District gives the sentence to hold on to: each jurisdiction follows its own floodplain criteria, and some projects may be subject to additional District review. West University Place is a Harris County city of approximately 2 square miles inside the Interstate 610 loop, which the West U guide covers in full.

The storm water system, commonly referred to as the drainage system, is operated and maintained by the Operations Division of Public Works. Run-off is collected in the curb and gutter streets and channeled to the underground piping network, which conveys the water to larger stormwater structures and ditches. From there it flows into Brays Bayou, then to the San Jacinto River Basin, Houston Ship Channel Segment 1007, and finally to Galveston Bay and the Gulf of Mexico (City of West University Place, read September 2026).

West U streets are designed to act as channels to convey water in combination with the underground pipe systems, in the city's own framing. A street holding water in a downpour is that design doing its work. The hydraulic grade line is the level to which water will rise as it flows through the drainage system, and rain intensity and duration matter, because the harder it rains, the greater the rate of flow and volume load on the system.

The drainage study the city published in January 2021 states the two metrics the system is held to. During a 2-year storm event the grade line should not exceed the gutter elevation in the street, and anything above that does not meet the design standard. During a 100-year storm event the hydraulic grade line should not pond beyond the right-of-way, which the report writes as the water not extending onto any homeowners' properties.

The ground does not follow the street grid. Sheet flow occurs from northwest to southeast, it does not follow the North-South layout of the roads throughout the City, which can cause issues of water flowing through properties, and the elevations of the City range from approximately 54 feet at the highest point to 45 feet at the lowest. On the northern edge of the city, some areas within the City of Houston drain into the city through sheet flow during major storm events, and the same study takes that into account.

One document with a similar name answers a different question. The Storm Water Management Plan the city has prepared is a pollution prevention plan, filed in compliance with the Storm Water Discharge Permit from the Texas Commission on Environmental Quality.

What did the city's own drainage study find?

In 2019 the city authorized the completion of a City Wide Drainage Modeling Study that evaluated and modeled existing conditions of its drainage system. The report is dated January 2021 and was prepared for the city by HT&J, LLC. Its central result is the sentence the city still prints in the present tense on its drainage improvement projects page, read September 2026: the majority of the City has limited drainage capacity, with some areas having less than 2-year capacity.

The report gives its own definitions for the events it models, and the findings mean little without them. A 2-year event is an amount of rain having a 50% chance of being equaled or exceeded in any given year. A 10-year event is rain with a 10% chance, and a 50-year event rain with a 2% chance. Each of those describes a single year, and the same chance applies again the next year.

The city has five major drainage systems that drain to Brays Bayou, delineated by the major trunk lines fed by collector storm sewer lines. Each capacity line below measures pipe capacity in the model dated January 2021 rather than what happens at a house. The Academy Street system accounts for approximately 260 acres, with its main trunk line below Academy Street, and the January 2021 report says street and property flooding are an issue for the 2-year event and above, with the vast majority of this system incapable of conveying storm runoff during a 2-year event as modeled. The College Street system accounts for 107 acres, with a main trunk line shared between the city and Southside Place, and the January 2021 report says street and property flooding are an issue for the 10-year event and above, with the entire system capable of conveying storm runoff during a 2-year event as modeled.

The Poor Farm Ditch system accounts for 361 acres, with Poor Farm Ditch as the major drainage channel of the system, and the January 2021 report says street and property flooding are an issue for the 10-year event and above, with the vast majority of this system capable of conveying storm runoff during a 2-year event as modeled, although some areas are undersized. The Buffalo Speedway system accounts for 356 acres, with its main trunk line below Buffalo Speedway, and the January 2021 report says street and property flooding are an issue for the 2-year event and above, with half of this system incapable of conveying storm runoff during a 2-year event as modeled. The Kirby Drive system accounts for 202 acres, with its main trunk line below Kirby Drive and part of the City of Houston, and the same January 2021 report says street and property flooding are an issue for the 10-year event and above, with the vast majority capable of conveying storm runoff during a 2-year event as modeled and only one area undersized.

One passage in that report names streets, and it carries its whole condition. The previous assessment reported that the dead-end streets within the College Street system, such as Swarthmore Street and Case Street, did not have capacity for the 2-year storm event. The January 2021 analysis shows that the areas do in fact have capacity for the 2-year storm, however the capacity is far exceeded during the 10-year storm event, and due to the low-lying nature of these dead-end streets, once water begins flooding into the streets it becomes one of the more susceptible areas to flooding in the City. That was the position in January 2021, before the improvements the same report recommends.

The target and the obstacle close the report. The proposed system provides a 50-year Level of Service, meaning storm sewers and streets capable of conveying storm water while eliminating structural damage for the 2-, 10- and 50-year events, with the grade line maintained below the gutter elevation during the 2-year event. The estimated amount of detention required to compensate the increase in discharge for the 100-year event is 260 acre-feet, and the report states that presently there is no space available for the detention pond within the City limits, recommending it be constructed outside the city. The total cost of the proposed drainage recommendations and street reconstruction projects is approximately $61,530,000, including a cost escalator factor for future years.

Which floodplain and which watershed is West U in?

The city's own statement sits at the scale of an area rather than a street. Most of the floodplain in West University Place is located adjacent to the City of Southside near Poor Farm Ditch, and the flood zones are contained within the Buffalo Bayou watershed and the Brays Bayou watershed (City of West University Place, read September 2026).

Its engineers wrote in January 2021 that a good portion of the City lies within the 100-year FEMA flood plain while the large majority of the City lies within the 500-year flood plain, and that this means there is an existing risk of the City flooding during the rain events that analysis modeled, the 2-, 10-, 50- and 100-year events, due to its location, terrain, and proximity to Brays Bayou. The same report defines both: a 100-year floodplain is the area of land that has a 1% chance of being inundated by flood waters from a bayou, stream or creek in a given year, and a 500-year floodplain is the area with a 0.2% chance.

Poor Farm Ditch itself is HCFCD Unit D111-00-00, a man-made drainage channel constructed more than 55 years ago that carries stormwater from surrounding neighborhoods in southwest Harris County to Brays Bayou. The Flood Control District says the channel provides drainage to portions of the cities of West University Place, Southside Place, Houston and Bellaire.

The Brays Bayou watershed covers approximately 127 square miles and includes three primary streams: Brays Bayou, Keegans Bayou and Willow Waterhole Bayou. It drains parts of the cities of Houston, Missouri City, Stafford, Bellaire, West University Place, Southside Place and Meadows Place. The District writes that severe flooding in the watershed has occurred on average at least once every decade, and that because a majority of the urbanization occurred prior to the advent of floodplain regulations and prior to delineation of the 1% floodplain, thousands of structures are now known to be in the currently mapped 1% floodplain.

The city assigns itself to two watersheds on its flood hazard page, the study it published in January 2021 says the city falls within the Brays Bayou watershed, and the Harris County Flood Control District names West University Place among the cities that watershed drains. Those statements stand side by side. A flood zone, though, is a fact about one parcel on one dated map, and a Houston address on the other side of the line answers to another jurisdiction's own floodplain criteria, which this site's page on the city line takes up.

What has actually happened in this watershed?

The Flood Control District's own Project Brays timeline dates the record, and every figure in it keeps the scale the District gives it. June 2001: a tropical storm brought record rainfall, with five-day rainfall exceeding 20 inches within the Brays Bayou watershed. April 2009: extensive flooding, with hundreds of structures flooded on Brays Bayou and a 24-hour rainfall of 7.6 inches recorded at Brays Bayou and Bellaire.

May 2015: more than 6,000 structures flooded and seven fatalities as a result of the highest rainfall recorded in the Buffalo and Brays watersheds, with nearly 11 inches in 3 hours on Brays Bayou. April 2016, the Tax Day Flood: an average of 12 to 16 inches of rain in 12 hours countywide. May 2016, the Memorial Day Flood: 8 to 13 inches of rain in north and northwest Harris County, with overbank and structural flooding along Willow Waterhole Bayou and Brays Bayou and more than 400 structures flooded in Harris County. August 2017: Hurricane Harvey, with many areas receiving more than 40 to 60 inches of rainfall in a four-day period.

The same timeline carries the counterweight in the District's own words: no structural flooding was recorded in the Brays Watershed as a result of Tropical Storm Imelda in September 2019. Project Brays, the District's partnership with the U.S. Army Corps of Engineers, is a multi-year, $480 million project; channel modifications from the Houston Ship Channel to Fondren Road were completed in 2021, and final bridge construction projects and overall Project Brays were completed in 2022.

Each figure above is a watershed, countywide or bayou figure at the scale its source gives it. The one Harvey fact this page carries about West U itself is a fact about a model: calibration of the XP-SWMM model was performed to validate its ability to forecast ponding depths based on the detailed assumptions and constraints, and that calibration was based upon known flooding depths during Hurricane Harvey.

What is changing about the county maps and the city's own projects?

The county's replacement maps and the city's construction run on different clocks. Draft MAAPnext flood maps are currently in draft form and are being shared for informational and educational purposes only. They are provided for awareness only and are not open for formal comments or appeals, they are not final, they cannot be used for insurance or regulatory decisions, and they are not open for public comment at this time. FEMA is anticipated to release Preliminary Flood Insurance Rate Maps after completion of its federal review and publishing process, and following that release FEMA will initiate a formal public review and appeal period.

While these maps will not set flood insurance rates, they may affect which properties are required to carry flood insurance once they become effective (Harris County Flood Control District, read September 2026). Against that sits the city's own statement, read September 2026, that the current effective FIRMs for West University Place are dated June 18, 2007.

On the east side the work is concrete. Package One included paving and drainage upgrades along University Boulevard from Buffalo Speedway to Kirby Drive and is complete. Package Two covers Wakeforest Avenue from Plumb Street to Pemberton Street, Rice from Wakeforest to Kirby Drive, and Duke Street from Buffalo Speedway to Wakeforest. Rice Avenue and Duke Street were completed in March of 2026, and the city has elected to re-bid the Wakeforest portion, with construction expected to last approximately one year once it begins.

On the west side, Halff Associates presented the recommended solution to the City Council in November 2023: a new storm sewer trunk line within the ELPH corridor, running from Bissonnet Street south to Brays Bayou, rerouting the existing storm sewer network on the west side into it, and upsizing storm sewers throughout the west side. It is a multi-phase project that will occur over several years, and the first phase is that trunk line within the 40-foot-wide ELPH property. The City Council approved the design contract with HDR Engineering on September 9, 2024, with a preliminary design expected to last 15 months and a final design and approvals taking approximately 13 months. The city's published history of the project gives those design durations and no completion date, so none is stated here.

What does the city require of a house here, and what does the insurance side look like?

All development in the floodplain requires a permit per Chapter 18 of the West University Place Code of Ordinances, and that development includes, but is not limited to, all new construction, filling, grading and paving. Substantially damaged or improved structures, where the cost of repair regardless of the cause of damage, or of improvements to a structure, equals or exceeds 50% of the building's market value, also require building permits and elevation certificates and are held to the same standards as new construction.

The city states that in some cases it has chosen to implement higher standards than the National Flood Insurance Program minimum. One higher standard it names in its floodplain ordinance is the requirement that all new construction and substantially improved structures be built to at least two feet above the base flood elevation, and that requirement extends to all equipment servicing the building such as an air conditioning unit. The city adds in the same breath that this higher standard provides added protection to structures but does not eliminate the flooding threat. How those standards work against the zoning envelope is set out on the page about what West U's rules let you build on a lot.

Insurance here is a clock rather than a price. The city participates in the National Flood Insurance Program, and there is a 30-day waiting period before a policy becomes effective. A flood insurance policy must be renewed every year. Where a policy was required by the bank or loan company at the time of a mortgage or home improvement loan, usually these policies just cover the building's structure and not the contents, though policies are also available to cover contents.

Effective October 1, 2020, property owners in the City of West University Place who are in the 100-year flood zone may be eligible for a reduction in flood insurance premiums because of the city's active participation in the Community Rating System, and the city states that it recently received a rating of 6 (City of West University Place, read September 2026). The city also publishes an odds figure with its own condition attached: in the life of a 30-year mortgage, there is a 26% chance of experiencing a flood if a property is located in the floodplain.

What should you ask for in writing before the option period ends?

Ask the city's Building Department, at 3826 Amherst Street in the Public Works building, for what it holds on the address. The city says permit information and elevation certificates on some properties in the floodplain are on file and may be requested from the Building Department, and some is the city's own word for how many properties that covers.

Ask the seller for the Seller's Disclosure Notice and read item 6. It asks whether the seller is aware of present flood insurance coverage, of previous flooding due to a failure or breach of a reservoir or a controlled or emergency release of water from a reservoir, and of previous water penetration into a structure on the property due to a natural flood event. It then asks, wholly or partly, whether the property is located in a 100-year floodplain, a 500-year floodplain, a floodway, a flood pool or a reservoir. Item 7 asks whether the seller has ever filed a claim for flood damage to the property with any insurance provider, including the National Flood Insurance Program, and item 8 asks whether the seller has ever received assistance from FEMA or the U.S. Small Business Administration for flood damage to the property.

The timing sits in the statute. The notice shall be delivered by the seller to the purchaser on or before the effective date of an executory contract binding the purchaser to purchase the property, and where a contract is entered without the seller providing the notice that section requires, the purchaser may terminate the contract for any reason within seven days after receiving the notice (Texas Property Code, section 5.008, read September 2026).

Ask the lender, in writing, whether it will require flood insurance and on what coverage. Then pull the effective map determination for the exact parcel and date the printout. The city says the FIRMs are available for viewing at the Building Department, that they are used by the city for compliance purposes and by insurance agents for flood insurance rating, and that FEMA's Map Service Center is a good resource for both current and historical maps. For a home built before the date of the effective FIRM, which the city gives as June 18, 2007, knowing what flood zone was in effect at the time of construction can be critical if there is a dispute with a mortgage lender or insurance agent.

Bring the elevation certificate, the disclosure and the map printout to your agent before the option period runs out, because those three documents are what an offer gets written against.

What can this page not tell you?

A zone for a specific West U street, block or address. That comes from the effective map for that parcel and from the determination pulled against it, dated on the day it is pulled.

Whether a particular house has flooded. That is answered by the seller's disclosure, the seller's claim history and an inspection, rather than by any map.

What the city's own model could not verify, the study dated January 2021 states outright: the flooding records received from the City were not verified, the available FEMA claims data did not provide a depth of flooding to use for model calibration, and building finished floor elevations were available for only a very limited amount of homes compared to overall number of homes in the City. Tailwater values for outfalls in the studied system had to be interpolated from known water surface elevations in Brays Bayou, since the model was not extended all the way to the outfall into the bayou.

What the replacement maps will show at a parcel is not knowable while they are in draft form, and the drafts themselves carry that limit on their face.

The text of the floodplain ordinance itself. The city's own summary of those rules is what is set out above, and the Development Services Department at 713.662.5833 is the counter to call for advice before you construct or place anything in the floodplain.

The city names the Harris County Flood Warning System gage closest to it as #430, located at Brays Bayou at South Main Street. That system measures rainfall amounts and monitors water levels in bayous and major streams on a real-time basis, and it is a measuring and alerting network rather than a risk lookup for an address. Find the gage on the District's own map, where the data may be delayed by approximately five minutes.

The District's own framing is the one to end on: community flooding can occur when rainfall intensity surpasses the ability of the local drainage infrastructure such as a storm sewer or roadside ditch, which is the kind of flooding the study the city published in January 2021 is about.