1. Overcoming Obstacles: Real LID Projects with Real Solutions
Jerry P. Preston, P.E., CFM
Department Manager – Hydrology & Hydraulics
EHRA
2014 LID in Houston Workshop, April 3, 2014

2. Objectives Moving from LID Concepts to “real-world” applications
Share ideas and information
Learn from experience and continually improve LID design and implementation
Objectives
2014 LID in Houston Workshop, April 3, 2014

3. CHALLENGES Sjolander Road Harris Co. Pct 2 Baytown, Texas
Flat terrain (natural ground slope +/- 0.03%)
Shallow Outfall Depth
Pipeline Crossings (+/-40 pipelines in three separate corridors in one-mile project)
Raw Water Canal Crossing
Contributing Offsite Drainage Area ~250 ac
Sjolander Road
Harris Co. Pct 2
Baytown, Texas
2014 LID in Houston Workshop, April 3, 2014

4. Linear Bioswales along roadway for detention storage, conveyance, SWQ
SOLUTIONS
Linear Bioswales along roadway for detention storage, conveyance, SWQ
“False-back” Inlets
Bioswales shallower than Storm Sewer
Strategic placement of Drainage Divides to avoid pipeline and raw water canal conflicts
Sjolander Road
Harris Co. Pct 2
Baytown, Texas
2014 LID in Houston Workshop, April 3, 2014

5. Sjolander Road Harris Co. Pct 2 Baytown, Texas
POST-CONSTRUCTION LESSONS LEARNED
Long, flat grades - consider extended underdrain and use multiple engineered soil filter “inlets”
Construction tolerances – standing water critical for proposed landscape areas
Siltation at Engineered Soil Filter – use temporary “bypass” drain during construction
Sjolander Road
Harris Co. Pct 2
Baytown, Texas
2014 LID in Houston Workshop, April 3, 2014

6. CHALLENGES/SOLUTIONS
Topography! - approx. 30’-40’ elevation change along proposed roadway required multiple “drops” to obtain effective storage along road
Mossy Oaks
Boulevard
Northern
Harris Co,
Texas
2014 LID in Houston Workshop, April 3, 2014

7. CHALLENGES/SOLUTIONS
Restricted ROW width (100’) – needed additional ROW width in select locations due to topography
Mossy Oaks
Boulevard
Northern
Harris Co,
Texas
2014 LID in Houston Workshop, April 3, 2014

8. POST-CONSTRUCTION LESSONS LEARNED
Erosion/rilling at slotted curb openings – provide sod strip or erosion control mat
Siltation at Engineered Soil Filter – use temporary “bypass” drain during construction
Mossy Oaks
Boulevard
Northern
Harris Co,
Texas
2014 LID in Houston Workshop, April 3, 2014

9. Convert temporary drain to permanent observation port/cleanout
Siltation at Engineered Soil Filter – use temporary “bypass” or overflow drain during construction
Convert temporary drain to permanent observation port/cleanout
Other Lessons Learned and Remaining Challenges
2014 LID in Houston Workshop, April 3, 2014

10. Other Lessons Learned and Remaining Challenges
Perforated Underdrains/Rain Tanks – strategic use of impermeable liners to prevent erosion or washouts in unwanted locations
Other Lessons Learned and Remaining Challenges
2014 LID in Houston Workshop, April 3, 2014

11. Other Lessons Learned and Remaining Challenges
Construction Staging – temporary drainage always requires coordination and planning
Construction Sequencing considerations for permeable pavers and engineered soils
Other Lessons Learned and Remaining Challenges
2014 LID in Houston Workshop, April 3, 2014

12. New design and construction techniques mean we’re learning on the fly
LID drainage can provide drainage and detention benefits, improved storm water quality, land use efficiency, improved aesthetics
New design and construction techniques mean we’re learning on the fly
Continuing Education process
Conclusion
2014 LID in Houston Workshop, April 3, 2014

13. Thank You – Questions? Jerry P. Preston, P.E., CFM
Department Manager – Hydrology & Hydraulics
EHRA
2014 LID in Houston Workshop, April 3, 2014