📊 Environmental Assessment Report

This comprehensive report analyzes both flood risk and industrial pollution exposure for this property. The assessment combines multiple data sources including USGS elevation, FEMA flood zones, historical storm modeling, and EPA Toxic Release Inventory records.

🌊 Part 1: Flood Risk Analysis

Property Overview

This section shows the fundamental characteristics of the property, including its elevation above sea level, FEMA flood zone designation, and our calculated overall flood risk rating based on historical data and topographic analysis.

Address

12802 KNOLLCREST ST HOUSTON 77015

Building Size

2,156 sqft

Total structure area from HCAD building records.

Elevation

8.41 ft

Height above sea level from USGS data.

FEMA Flood Zone

High Risk - 1% annual chance with established base flood elevation

Overall Risk

High

Property flooded at 1.6ft depth. Risk based on flood depth at structure.

Risk Assessment Outputs

These detailed metrics show the technical outputs from our flood risk model. They include predicted water depths at the property during a 5000-year flood event and estimated flood damage based on USACE methodology.

Risk Rating

High

Flood Depth

1.59 ft ±0.5 ft

Depth of water above ground level.

Water Surface Elevation (WSE)

N/A

Water surface elevation data not available.

Area Inundated

N/A

Data not available

Nearest Bayou Stage

N/A

No nearby bayou within monitoring range

Depth-Damage Estimate (HCAD Valuation)

Based on HCAD building value of $149,341 (2,156 sqft). Using U.S. Army Corps of Engineers depth-damage curves.

Depth-Damage Estimate (Neighborhood Comparison)

No neighborhood valuation estimate available. Building exists (2,156 sqft) but no comparable neighborhood data found.

Analysis Method

COG Bathtub Model

Raster-based flood inundation query

Flood Simulation

This simulation shows whether the property would flood based on a 5000-year flood event with 3m (9.84ft) water level. Use the interactive tool to explore different scenarios.

⚠️ Property Would Be Flooded

Flood Depth: 1.59 feet
Severity: Minor

Adjust Flood Simulation

The analysis above uses default settings (5000-year flood, 3m/9.84ft water level). To explore different flood scenarios with interactive maps, return to the main tool:

Open Interactive Analysis Tool

Flood Risk Recommendations

Based on the property's flood risk profile, here are specific action items to consider.

This property is in a high-risk flood zone. Flood insurance is required for mortgages.
Consider flood mitigation measures like elevated utilities and flood vents.
Review the interactive flood simulator to understand how different rainfall events could affect this property.
Contact Harris County Flood Control District (HCFCD) for drainage projects and flood information.
Simulation shows flooding at current water level - review property drainage and consider mitigation.

🏭 Part 2: Industrial Pollution Exposure

Property Pollution Ranking

Moderate

Higher pollution than 65% of Houston homes

This ranking compares pollution levels within 2 miles of this property against 10,000 randomly sampled Houston metro properties. Lower percentiles indicate higher pollution exposure.

Industrial Pollution Nearby (Last 10 Years)

110 thousand lbs

High

16.9x more than typical Houston property
≈ 6 dump trucks of chemicals within 2 miles

Total chemical releases from all industrial facilities within a 2-mile radius over the past decade (2014–2024). Data from EPA's Toxic Release Inventory tracking air, water, and land discharges.

💨 Air Pollution (Last 10 Years)

110 thousand lbs

High

22.9x more than typical Houston property

Chemicals released into the air from nearby facilities over 10 years. Includes both fugitive emissions (leaks, evaporation) and stack emissions (smokestacks, vents). May affect local air quality.

💧 Water Pollution (Last 10 Years)

14 lbs

Above Typical

Most Houston properties have none nearby

Chemical discharges to surface water (bayous, streams, drainage) from industrial facilities within 2 miles over the past decade. May impact local waterways and drainage systems.

❤️ Why It Matters

High chemical activity nearby can indicate industrial zones, truck traffic, or potential odor and noise issues. These factors may affect air quality, long-term property desirability, and neighborhood character. This data helps you understand the industrial footprint around your property.

🏙️ Houston Metro Benchmarks

Comparison with typical Houston properties (based on 10,000 randomly sampled homes). All measurements are for chemicals released within a 2-mile radius.

Period	Total	Air	Water
Typical Houston Property (2014-2024)	6,524 lbs	4,822 lbs	0 lbs
This Property (2014-2024)	110,237 lbs	110,223 lbs	14 lbs
Typical Houston Property (2024 Only)	2 lbs	1 lbs	0 lbs
This Property (2024 Only)	3,480 lbs	2,893 lbs	3 lbs

📊 How This Property Compares to Houston Metro

Based on a random sample of 10,000 Houston properties, this chart shows the distribution of pollution levels across the metro area. The highlighted bar indicates where this property falls compared to other homes. Lower percentiles mean higher pollution exposure.

0-9thMost Polluted

9.9%

10-19th

10.1%

20-29th

9.9%

30-39th

10.1%

40-49th

9.7%

50-59th

10.2%

60-69th

70-79th

5.8%

80-89th

4.3%

90-100thLowest Pollution

34.2%

Higher pollution than 65% of Houston homes

Each bar's width represents the percentage of Houston homes in that pollution range. This property ranks in the 30-39th percentile (higher than average pollution).

Top chemicals released near this property (past 10 years):

Styrene, Xylene (mixed isomers), Toluene, n-Hexane, Ethylbenzene

View the full list of 23 chemicals below.

Chemicals Released (2014-2024, 10-Year Total) (23 chemicals)

#	Chemical	CAS#	Air (lbs, 10yr)	Water (lbs, 10yr)	Total (lbs, 10yr)
1	Styrene	100-42-5	26,310 lbs	0 lbs	26,310 lbs
2	Xylene (mixed isomers)	1330-20-7	21,357 lbs	0 lbs	21,357 lbs
3	Toluene	108-88-3	13,120 lbs	0 lbs	13,696 lbs
4	n-Hexane	110-54-3	12,725 lbs	0 lbs	12,725 lbs
5	Ethylbenzene	100-41-4	10,531 lbs	0 lbs	10,531 lbs
6	Methanol	67-56-1	6,541 lbs	0 lbs	6,541 lbs
7	Benzene	71-43-2	6,362 lbs	0 lbs	6,362 lbs
8	Ammonia	7664-41-7	3,125 lbs	0 lbs	3,125 lbs
9	Hydrochloric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size)	7647-01-0	3,066 lbs	0 lbs	3,066 lbs
10	Cyclohexane	110-82-7	1,732 lbs	0 lbs	1,732 lbs
11	Chlorine	7782-50-5	1,412 lbs	0 lbs	1,412 lbs
12	Formic acid	64-18-6	1,012 lbs	0 lbs	1,012 lbs
13	Certain glycol ethers	N230	903 lbs	0 lbs	903 lbs
14	1,2,4-Trimethylbenzene	95-63-6	863 lbs	0 lbs	863 lbs
15	Ethylene glycol	107-21-1	398 lbs	0 lbs	398 lbs
16	Nickel	7440-02-0	376 lbs	1 lbs	376 lbs
17	Phthalic anhydride	85-44-9	184 lbs	0 lbs	184 lbs
18	Maleic anhydride	108-31-6	139 lbs	0 lbs	139 lbs
19	Naphthalene	91-20-3	29 lbs	0 lbs	29 lbs
20	Nitric acid	7697-37-2	28 lbs	0 lbs	28 lbs
21	Nonylphenol Ethoxylates	N535	10 lbs	0 lbs	10 lbs
22	Lead And Lead Compounds	N420	0 lbs	7 lbs	7 lbs
23	Lead compounds	N420	0 lbs	6 lbs	7 lbs

Top chemicals released near this property (2024 only):

Methanol, Toluene, Cyclohexane, Certain glycol ethers, Formic acid

View the full list of 7 chemicals reported within 2 miles for 2024.

Chemicals Released (2024 Only) (7 chemicals)

#	Chemical	CAS#	Air (lbs/yr)	Water (lbs/yr)	Total (lbs/yr)
1	Methanol	67-56-1	1,343 lbs	0 lbs	1,343 lbs
2	Toluene	108-88-3	314 lbs	0 lbs	890 lbs
3	Cyclohexane	110-82-7	759 lbs	0 lbs	759 lbs
4	Certain glycol ethers	N230	214 lbs	0 lbs	214 lbs
5	Formic acid	64-18-6	173 lbs	0 lbs	173 lbs
6	Nickel	7440-02-0	90 lbs	0 lbs	98 lbs
7	Lead compounds	N420	0 lbs	3 lbs	3 lbs