Stormwater
LAN provides innovative stormwater management solutions, including master planning, drainage design, flood mitigation, and regulatory compliance for public and private clients. Our multidisciplinary team delivers resilient, cost-effective strategies that protect communities, enhance water quality, and support sustainable development.
Channel & Stream Restoration
LAN delivers channel and stream restoration services, focusing on erosion control, stream stabilization, and natural channel design to improve flood resilience, water quality, and ecological health for communities across Texas and beyond.
Services
Erosion control and streambank stabilization
Natural channel design and bioengineering
Bank stabilization and scour evaluations
Channel alignment modifications and widening
Floodplain and watershed modeling (1D/2D H&H)
Sediment transport analysis
Outfall replacement and pipe rehabilitation
Back slope interceptors and rip-rap placement
Environmental permitting
Trail and park amenity integration
Utility coordination and relocation
Construction phase services and maintenance planning
Water quality and stormwater BMP design
Project Gallery
-
![Aerial view of a construction site with heavy machinery installing a large pipeline through a cleared area surrounded by trees.]()
Purgatory Creek Channel Improvements – City of San Marcos
LAN performed a watershed-scale drainage study and designed two miles of major channel widening in San Marcos, TX, removing 91 homes from the floodplain and reducing flood risk for 200 homes, while integrating park amenities and environmental restoration.
-
![An aerial view showing construction of pipelines along a winding dirt road near a highway overpass, with additional roads, greenery, and industrial buildings in the background.]()
Lebow Channel at NE 28th Street Drainage Improvements – City of Fort Worth
LAN designed 1,500 LF of natural stream in Fort Worth, TX, to minimize road overtopping and flooding, incorporating sediment transport analysis, trail design, and floodplain permitting.
-
![Construction site with heavy machinery, workers installing a large underground pipeline in a trench, clear sky with clouds.]()
Cottonmouth Creek Riparian Restoration – Brookfield Residential
LAN led the restoration of 1.1 stream miles in Austin, TX, transforming an impaired creek corridor through grading, native planting, stormwater controls, and trail connectivity to improve floodplain health and biodiversity.
-
![People cycling and walking on a paved path along a river with multiple overpasses above during twilight.]()
Buffalo Bayou Erosion Control & Stream Restoration – Harris County Flood Control District
LAN provided erosion control and stream restoration along Buffalo Bayou in Houston, TX, stabilizing banks and improving water flow.
Detention and Retention
LAN is a leader in the planning, design, and implementation of detention and retention facilities that mitigate flooding, improve stormwater management, and enhance community resilience.
Services
Feasibility studies and master planning
Hydrologic and hydraulic (H&H) modeling (1D/2D)
Site selection and layout alternatives
Wet-bottom and dry-bottom basin design
Environmental permitting and compliance
Construction documents and phasing plans
Community engagement and public outreach
Construction management and inspection
Ecological restoration and landscape architecture
Grant and funding support
Utility and ROW coordination
Water quality and stormwater BMP integration
Project Gallery
-
![An aerial view of a construction site showing dirt roads, construction equipment, and trees surrounding the area.]()
Exploration Green Detention Facility – Clear Lake City Water Authority
LAN planned and designed a $49M transformation of a former golf course into five detention ponds and a 200-acre urban green space, protecting up to 3,000 homes from flooding in Clear Lake City, Houston.
-
![Aerial view of a highway construction site with blue pipes and a curved road, adjacent to an overpass with moving vehicles, near green fields and sparse trees.]()
Lauder Stormwater Detention Basin – Harris County Flood Control District
LAN developed the concept, feasibility, and detailed design for a three-phase, 1,476 acre-foot extended detention basin in Houston, providing flood risk reduction for over 15,000 residents in the Greens Bayou watershed.
-
![Construction workers installing a large pipeline in a trench, with excavators and cranes working on a construction site under a partly cloudy sky.]()
Kuykendahl Regional Detention Basin – Harris County Flood Control District Tarrant Regional Water District
LAN designed a 2,900-acre-foot regional detention basin at the confluence of three Greens Bayou tributaries in Houston, removing hundreds of homes from the floodplain and providing recreational and wetland amenities.
-
![Aerial view of green trees, grass fields, and a body of water with a city skyline in the distance.]()
Benson Bayou Detention Basin – City of League City
LAN completed master planning, modeling, and site selection for a regional detention basin in League City, reducing flood risk for homes and businesses while minimizing downstream impacts.
Hydrologic and Hydraulic Modeling
LAN leads hydrologic and hydraulic (H&H) analysis and modeling, providing innovative solutions for flood risk reduction, stormwater management, and infrastructure resilience.
Services
Drainage criteria and ordinance development
Stormwater infrastructure design
Quality assurance, quality control and third-party review
Water quality and low impact development (LID) modeling
Erosion and scour evaluations
Capital improvement planning and programming
Environmental permitting and reporting
Community rating system (CRS) program support
Master planning and watershed studies
Hydrologic and hydraulic (H&H) modeling (1D/2D)
Floodplain mapping and FEMA studies
Open channel and culvert analysis/design
Project Gallery
-
![Aerial view of a construction site with heavy machinery and a dirt road surrounded by trees.]()
Lexington Boulevard Drainage Improvements – City of Sugar Land
LAN performed detailed H&H modeling and designed drainage improvements to address storm sewer deficiencies that caused ponding and structural flooding during extreme storm events.
-
![Under construction area with large blue pipes along a dirt road, nearby highways, and wooded areas with trees.]()
Carson Creek - Dalton Lane Low Water Crossing Improvements – City of Austin
LAN employed 1D/2D HEC-RAS modeling in Austin to design bridge and drainage improvements, reducing overtopping and improving access during storm events.
-
![Construction workers installing a large underground pipeline with heavy machinery in a trench on a sunny day.]()
Oaks of Clear Creek Drainage – City of League City
LAN performed hydraulic and hydrologic analysis and modeling with InfoWorks ICM 1D/2D to develop solution alternatives to reduce flood risk in a neighborhood that historically experienced frequent structural flooding and excessive street inundation.
-
![A map overlay showing buildings and streets with blue and purple shading indicating elevation or another data layer.]()
Shoal Creek - Burrell Drive Flood Risk Reduction – City of Austin
LAN performed 1D/2D hydrologic and hydraulic analysis for 174-acres of the Shoal Creek Watershed to improve the existing storm drain system, mitigate flooding, and address 11 building and 15-yard flooding complaints from neighborhood residents.
-
![Aerial view of suburban neighborhood with winding streets and houses, surrounded by a network of water channels.]()
W100 – W151W153 Regional Preliminary Engineering Study – Harris County Flood Control District
LAN performed 1D/2D hydrologic and hydraulic modeling to develop stormwater improvement concepts in the highly developed area. The study area was delineated into seven problem areas which were then prioritized based on structural flooding, miles of flooded roadways, impacted populations, and total area of inundation.
Master Planning
LAN delivers comprehensive master planning services that help communities and organizations anticipate future growth, optimize infrastructure, and develop actionable, cost-effective strategies for water, wastewater, stormwater, transportation, and facilities systems.
Services
Impact fee analysis
Hydraulic and hydrologic modeling
Asset management and condition assessment
Operations and maintenance planning
Water system master planning
Wastewater system master planning
Stormwater/drainage master planning
Facilities master planning and condition assessment
Capital improvement plan (CIP) development
Population and demand forecasting
Funding and rate analysis
Regulatory compliance and permitting
Stakeholder and public engagement
Project Gallery
-
![Aerial view of a road construction site in a forested area with workers, construction equipment, and large pipes.]()
Little Cypress Creek Master Drainage Plan – Harris County Flood Control District
LAN created a comprehensive watershed master drainage plan in Houston, TX, for flood risk management, including hydrologic and hydraulic modeling and multi-benefit public amenities.
-
![Aerial view of a highway construction site with large blue water pipes on the ground, beside a curved road, with multiple overpasses and a wooded area, under construction.]()
Master Drainage Plan – City of Galveston
LAN developed a citywide master drainage plan for Galveston, TX, covering 64 square miles and integrating stormwater modeling, flood risk reduction, and CIP recommendations.
-
![Construction workers inspect a large pipeline in an excavation site under a partly cloudy sky, with construction equipment including excavators and cranes in the background.]()
Brays Bayou Master Plan – Harris County Flood Control District
LAN provided comprehensive engineering analysis and planning to guide channel improvements, stormwater detention, and flood mitigation strategies along Brays Bayou. The master plan supports long-term flood risk reduction and enhances drainage infrastructure for the surrounding Houston communities.
-
![A small creek running through a grassy park with trees and a blue sky overhead.]()
Beaumont Master Drainage Plan – City of Beaumont
LAN provided comprehensive hydrologic and hydraulic modeling, flood risk assessment, and prioritized recommendations for drainage improvements citywide. The plan equips the City with actionable strategies to reduce flooding, enhance stormwater management, and support resilient community growth.
-
![Map of a residential area showing streets, water features, and neighborhood boundaries with labels for streets such as Greenway Drive, Woodchester Drive, Brambleberry Drive, and Raven Court Drive.]()
Covington Woods Master Drainage Plan – City of Sugar Land
LAN completed advanced 2D modeling to address significant drainage and flooding challenges in this mature residential area. The plan identified and prioritized cost-effective improvements—including storm sewer and channel upgrades—to reduce flood risk in low-lying neighborhoods with limited overland outlets and insufficient storm sewer capacity.
Storm Sewer
LAN provides comprehensive storm sewer engineering services, specializing in the planning, analysis, design, and rehabilitation of stormwater conveyance systems to reduce flooding and improve drainage infrastructure for municipalities and public agencies.
Services
Inlet and manhole evaluation
Flood risk and level-of-service analysis
GIS-based infrastructure mapping and data management
Construction phase services and phasing plans
Storm sewer system analysis and design
Hydrologic and hydraulic (H&H) modeling
Condition assessment and prioritization
Rehabilitation and replacement
Water quality and BMP integration
Capital improvement planning and prioritization
Regulatory compliance and permitting
Trenchless technologies and tunnels
Project Gallery
Grant Funding
LAN assists clients in securing and managing stormwater grant funding to support the planning, design, and construction of projects that mitigate flooding, improve drainage infrastructure, and enhance community resilience.
Services
Identify stormwater/drainage grant opportunities
Assess client and project eligibility
Develop and submit grant applications (FEMA, HUD, TWDB, EPA)
Conduct benefit-cost analyses
Coordinate with agencies (FEMA, USACE, TDEM, TWDB)
Support grant compliance, reporting, and audits
Scope projects and estimate costs for grants
Assist with permitting
Lead stakeholder outreach for grant projects
Track and manage grant funds through closeout
Manage multi-project, multi-grant programs