The Cypress Creek Flood Control Coalition Frequently Asked Questions (Education):

Is my home in a floodplain?

Your homeowners’ insurance agent can determine whether your home is in or out of the 100-year floodplain. If you decide to purchase flood insurance under the National Flood Insurance Program (NFIP), the agent might request a surveyor-certified elevation certificate to determine the elevation of your home relative to the Base Flood (100-year) elevation. This elevation is a key determinant of the flood insurance rate you will pay.

Are there other ways to determine if my home is in the floodplain?

Yes, you can go to Tropical Storm Recovery Project (TSARP) website (, or check FEMA’s foodplain maps, copies of which can be found on their website ( These maps will show your home’s relationship to the floodplain. For additional information, contact your particular municipal floodplain administrator, or for unincorporated Harris County, the Harris County Permits office.

What is an elevation certificate?

A certificate issued by a professional surveyor which shows the elevation of the bottom floor of a structure on a given property. If this certificate shows that the property is above the Base Flood Elevation (BFE) despite the property being shown in the 1% (100-year) floodplain on the Flood Insurance Rate Map (FIRM), it can be used to obtain a lower insurance rate.

What is Base Flood Elevation (BFE)?

This is the elevation above the average sea level that waters from a 1% (100-year) flood will reach at a given point along a creek or bayou. These elevations are determined using hydrology and hydraulic computer models, and are then mapped on Harris County’s topographic data to produce the 1% floodplain.

What are Flood Insurance Rate Maps (FIRMs)?

Produced by the Federal Emergency Management Agency (FEMA), FIRMs show areas subject to flooding from a primary flood source, typically major rivers, bayous, creeks and their subsidiaries (sheetflow flood risks are not shown). FIRMs help property owners assess the risk of out-of-bank flooding in their specific areas and are used by the National Flood Insurance Program (NFIP) to establish risk zones/insurance premiums.

What is the National Flood Insurance Program (NFIP)?

NFIP is a program administered by FEMA, which produces Flood Insurance Rate Maps (FIRMs) that are based on technical analysis and stream gauge measurements of historical flooding information. FIRMs include flood risk information, special flood hazard areas, Base flood elevations (called “100-year” elevations), areas subject to inundation by 100-year and 500-year floods along primary channels, and common features like streams, highways, roads, and railroads. Call 1-800-477-4661 for information about obtaining coverage under the National Flood Insurance Program.

How can I obtain or view a Flood Insurance Rate Map?

For a small fee, you can order a FIRM from the FEMA Map Center by calling 1-800-358-9616. To do this, you will need a “Panel Number” for the specific area in question. Normally, you can view a FIRM or get a panel number by contacting your mortgage company, homeowners’ insurance agent, or the local city planning or engineering office.

Does my standard homeowners’ policy include flood insurance?

No, you must arrange for flood insurance separately. It is sold through private insurance companies and is financially backed by the federal government. Rates are the same from all companies. If your home is not located in a “mapped” floodplain, the cost is relatively inexpensive (losses not covered under a flood policy include out-of-home living expenses and damage to automobiles and to contents below the lowest elevated floor of your property). For guidance on how to purchase a flood insurance policy, contact your insurance agent or visit the National Flood Insurance website (

Who needs flood insurance?

Even homeowners that do not live in a mapped floodplain are vulnerable to flooding.  Because everyone lives in a potential flood zone (see “sheetflow” and “ponding”), the Cypress Creek Flood Control Coalition and the Harris County Flood Control District recommends that all Cypress Creek Watershed citizens carry flood insurance.

If the FEMA Flood Insurance Rate Maps show that my house is not in a flood zone, why do I need flood insurance?

FEMA Flood Insurance Rate Maps (FIRMs) show the floodplains of primary sources such as major rivers, bayous, creeks, and their tributaries. But flooding from sources not identified on the FIRM occurs often in Harris County (see “sheetflow” and “ponding”). Nationally, one-third of all flood loss claims are from properties located outside of the mapped 1% (100-year) flood plain.

New Flood Insurance Rate Maps for Harris County will become official June 18, 2007. Are the old maps wrong?

Old or new, FEMA Flood Insurance Rate Maps are estimates. Older maps used technology current at the time those maps were developed. The new maps were drawn using today’s state-of-the-art technology. In short, older maps are good estimates of where the floodplain exists, but newer maps improve upon those estimates.  However, even the new maps do not take into account future development. Development that was taken into account was collected well before the new maps become official (a major reason why CCFCC and HCFCD are preparing the “Future Conditions Flood Hazard Boundary” technical study).

What is the Harris County Flood Control District (HCFCD)?

Created by the State Legislature in 1937, HCFCD is a special purpose district primarily established to build projects. Its mission: to reduce flood damage with appropriate regard for community and natural values. HCFCD devises and implements flood damage reduction plans, and then maintains the infrastructure. It does not have regulatory authority over development. Municipalities within Harris County and the County Engineer have some regulatory authority through their respective construction and building permit programs (See Glossary for more details).

Flooding is a recurring problem in some neighborhoods, but not in others. Why?

Older subdivisions were built prior to current regulations that restrict certain uses of flood-prone land.  Typically, streets and storm sewers are designed for normal rainfall events, and a heavy rainfall can overload these systems. When this happens, water “ponds” in the streets and then tries to flow overland to a creek or bayou, flooding homes along the way.

Is street flooding normal?

Yes, because streets are often considered part of the drainage system. During a typical rainstorm, water flows through storm sewers or down roadside ditches to a creek or bayou. If this storm sewer or ditch capacity is exceeded, streets will hold the accumulated water until the normal systems can drain them.

What is sheetflow (overland flow) flooding?

Sheetflow flooding occurs when an intense rainfall exceeds storm sewer or roadside ditch capacity. This water can accumulate (see “ponding” below) in subdivision streets deep enough to flood homes that are not in a floodplain. The water seeks the path of least resistance to a nearby channel by flowing overland.  Homes and other structures in this path may be flooded even though they are not shown to be in the floodplain on a Flood Insurance Rate Map.

What is ponding?

Ponding is the accumulation of water after a rainfall that gathers in low-lying areas throughout a watershed. It usually drains into a bayou or creek.

What is run off?

Run off is water from rainfall that is not absorbed by the ground. It first flows into the local drainage system, and then into a local river, creek, or bayou.

What does “buy out” mean?

The purchase or “buy out” of flood-prone houses is one of the most cost-effective tools in the HCFCD’s flood damage reduction toolbox. During heavy rains, it’s quite natural for Cypress Creek to occupy its floodplain. It’s not natural for homes to be built there. Buying and removing these flood-prone structures is the best way to ensure that they are not again damaged by floods.

Why does the government buy flooded homes?

For two reasons: because homeowners’ lives are at risk, and because recurrent flood losses drain government and community resources. A buy out can be the most cost-effective method of addressing recurrent flooding problems when compared to the alternative costs of building larger channels, stormwater detention basins, and other flood mitigation projects (or repetitively paying flood insurance claims).

If I think my home qualifies, how does a “buy out” work?

The process varies depending on the requirements of the specific funding source. Generally speaking, homes are appraised at fair market value by certified independent appraisers, homeowners are screened for relocation assistance eligibility, negotiations are carried out with the Harris County Right-of-Way Division, and homeowners meet with HCFCD staff counselors before the transaction is complete. Potentially eligible homes are generally ranked according to the risk, severity and history of flooding. When HCFCD funds are leveraged with other funds, the financial partner’s ranking priority may supercede that of the HCFCD, but the ultimate objective is the same…reducing damage and losses caused by floods.

Has the local “buy out” program been effective?

Between 1989 and the Tropical Storm Allison experience of June, 2001, HCAD and various partners have purchased 440 of the most repetitive flood-loss homes in Harris County, costing $44 million. Since Tropical Storm Allison, HCFCD, in partnerships with FEMA and the State of Texas, has purchased an additional 2,000 homes, costing $170 million. HCFCD also maintains a list of candidates for buy out when funds become available. It is currently seeking additional funds for the buy out of homes that were flooded in October 2002 and for other homes that repeatedly flood.