Buil Buildin ding g TR TRUST UST in in Or Oreg egon on - - PowerPoint PPT Presentation

Buil Buildin ding g TR TRUST UST in in Or Oreg egon

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Presented by Doug Beyerlein, PE, PH, D.WRE: Clear Creek Solutions Chris Hass, PE: Contech Engineered Solutions Scott Mansell, PhD, PE: Clean Water Services

In Intr trodu

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ction

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Ch Chris is Has ass, s, PE Stormwater Consultant – OR 503-807-2322 CHass@ContechES.com Sc Scott t Man ansell, sell, PhD, , PE Senior Engineer 503-681-4466 MansellS@CleanWaterServices.org Do Doug g Bey eyerlei erlein, n, PE PE, PH, D.WR WRE Principal Engineer 425-225-5997 beyerlein@clearcreeksolutions.com

Ag Agenda enda

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Intr oduction to TRUST and Continuous Simulation Modeling

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Continuous Modeling Example

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Applications of TRUST by Clean Water Ser vices

TRUS TRUS T

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Developed for Clean Water Ser vices.

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Includes the entir e Tualatin River Basin.

Tualatin River Urban Stormwater Tool

TRUS TRUS T T Map Map Int Interf erfac ace

TRUS TRUS T

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Long-ter m r ain gauges

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1 948-present

TRUS TRUS T

TRUST is built on the WWHM HSPF softwar e platfor m. CCS has developed similar stor mwater softwar e for

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9 counties in western Washington

§ Alameda, Santa Clar a, San Mateo counties in SF Bay Area § Sacramento, San Diego, Riverside, Orange counties in Califor nia § City of Salinas, Califor nia § South Korea

Wh Why y TRUS TRUS T? T?

1 . Easy to use. 2. Wide range of BMPs 3. Both water quality and flow control BMPs 4. Fast set up and execution. 5. Has been customized with local data. 6. Continuous simulation hydr ology.

Single Event Methods:

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Rational Method: Q = CIA (1 880s)

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SBUH SCS Curve Number s (1 930s) Cr eated pr e-computer . Simplified for calculation by slide r ule. REQUIRES MULTIPLE MAJOR ASSUMPT IONS.

Old Old S choo S chool: l: S ingl S ingle e Even ent t Model

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Runoff frequency is the same as r ainfall fr equency (the 1 00-year stor m causes the 1 00-year flood). FALSE

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Antecedent soil moistur e conditions ar e always the same. FALSE

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Rainfall events ar e never back to back (one stor m immediately after another ). FALSE

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Stor m shape and r ainfall distr ibution ar e always the same. FALSE POOR ASSUMPTIONS!!!

S ingl S ingle e Even ent M t Metho ethod d Assum Assumpt ption ions

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Still the cur r ent standard most places in Or egon, but…

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Pr oduces stor mwater control facilities that do not pr event incr eased str eam channel

er osion.

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Pr oduces stor mwater control facilities that do not pr event flooding downstr eam when combined with flows fr om other developed subbasins.

S ingl S ingle e Even ent M t Metho ethods ds

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Stormwater contr ols sized using single events have

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Increased erosion

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Matched predevelopment peak only

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Large incr ease in dur ation of flows in the erosive r ange.

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Caused flooding

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Extended per iod of peak flow from

from multiple subbasins causes mor e peak over lap downstream

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Inaccur ate pr ediction of antecedent

antecedent moistur e conditions, precipitation, and back-to-back events

S ingl S ingle e Even vent t Method ethods

https:/ / www.researchgate.net/ figure/ Hydrograph-Analysis-for-Conventional-Detention-of-the-Two-Year-2-h-Event-in-Fort_fig1_318613692

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Runoff frequency is statistically calculated from the long-term hourly simulated r unoff data.

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Antecedent soil moistur e conditions ar e calculated (and change) ever y time step.

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Rainfall & evaporation are from the measur ed histor ical r ecor d.

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Stor m shape and r ainfall distr ibution ar e fr om the measur ed histor ical r ecor d.

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Calibr ation to r eal stor ms and r eal str eamflow data Bad assumptions fr om single event methods ar e gone!

A Be A Better er Way: y: Con Contin tinuo uous us S im S imula ulatio tion S tor S tormwater er Met Metho hods

His History tory of

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PF HS PF Mod Model el & & TRUS TRUS T T S

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S

• ftwar

are

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1 966: Stanfor d Water shed Model

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1 979: EPA HSPF

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2001 : Western Washington Hydr ology Model (WWHM)

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201 5: T RUST

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201 9: TRUST 201 9 (update of or iginal T RUST)

HS PF HS PF

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Continuous simulation hydrology computes the entir e hydr ologic cycle for multiple year s.

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Multiple-year hour ly histor ic rainfall used to gener ate gener ate multiple-year hour ly hour ly r unoff data.

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Stormwater runoff = surface runoff + inter flow.

TRUS TRUS T

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Continuous simulation computations from HSPF (included in T RUST softwar e).

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HSPF r uns in the backgr ound with local calibr ated par ameter values and meteor ological data.

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HSPF sponsor ed and funded by EPA and USGS.

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Continuous simulation hydrology to compute stormwater r unoff for both conditions.

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Models & sizes BMPs to mitigate development effects

TRUS TRUS T

Pr edevelopment Post-development

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T he entire water cycle is computed on an hourly time step for multiple year s.

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T RUST computes changes in soil moistur e, evapotranspir ation, and r unoff ever y time step.

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T hr ee types of r unoff:

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Sur face r unoff

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Interflow (shallow subsurface r unoff)

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Gr oundwater / base flow

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Can automatically size and compute r outing thr ough a number of types of BMPs.

TRUS TRUS T

TRUS TRUS T

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Flow contr ol standard based on er osive flow range.

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Flow contr ol standard is typically ½ of 2- year to 1 0-year flow.

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Adjustable within TRUST for differ ent jur isdictions / differ ent applicable range.

TRUS TRUS T

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Flow Dur ation Analysis: Per cent of time the flow exceeds a specific value

• ver simulated per iod.

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Requir es continuous simulation hydr ology.

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Pr oduces stor mwater control facilities that ar e cor r ectly sized because:

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Pr edevelopment par ameter values are calibr ated to local hydr ologic conditions and land uses.

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Runoff calculations ar e mor e accur ate due to better antecedent moistur e conditions and r eal, measur ed stor m events.

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Pr edevelopment flood fr equency values ar e accur ate because based on flow, not pr ecipitation and based on r eal storms.

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Stor age volumes to r educe flows to pr edevelopment conditions ar e mor e accur ate because they have been ‘tested’ over many year s in the model.

Con Continu tinuou

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s Simul Simulation tion with with TRUS TRUS T

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Pr oduce stor mwater contr ol facilities that do not incr ease stream channel er osion because:

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Match pr edevelopment flow durations in the er osive flow range in the str eam instead of peak flows.

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T he number of hours of high (erosive) flows in the stream do not incr ease above pr edevelopment conditions.

Con Continu tinuou

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s Simul Simulation tion with with TRUS TRUS T

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Dr ainage ar eas ar e divided into per vious land segments

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Soil

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Vegetation

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Slope

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Imper viousness

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Per vious and imper vious segments ar e linked to r outing and LIDA, e.g.

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Extended dr y basins

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Constr ucted water quality wetlands

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Rain gar dens

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Por ous pavement

Using Using TRUST TRUST

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User locates pr oject on Tualatin Basin map, inputs pr e- and post-development land use and pr oposed mitigation measures.

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Pr edevelopment and mitigated flows ar e compar ed at Point of Compliance (POC).

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Mitigation measur es designed to meet flow contr ol standar d and/ or water quality tr eatment standard.

Using Using TRUST TRUST

1 . Extended Dr y Basin 2. Constr ucted WQ Wetland 3. Natur al Channel 4. Gr avel Tr ench/ Bed 5. Flow Splitter 6. SSD Table 7. Stor age Tank 8. Stor age Vault

TRUS TRUS T T Routi

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ng/S /S tor

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age e Elem Elemen ents ts

1 . Rain Gar den 2. LIDA Swale 3. Infiltr ation Planter 4. Flow-T hr ough Planter 5. Por ous Pavement 6. Gr een Roof

TRUS TRUS T T LIDA LIDA Elem Elemen ents ts

TRUS TRUS T

Each element is visually represented on the Schematic screen with all of the linkages between elements shown.

TRUS TRUS T

User has complete control of TRUST element input data.

Ag Agenda enda

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Intr oduction to TRUST and Continuous Simulation Modeling

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Continuous Modeling Example

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Applications of TRUST by Clean Water Ser vices

Pr Project

• ject Ex

Examp ample le Ov Overview erview

§ Pr e-developed Condition

§ Select location § Use NRCS for soil type § Set up basin ar ea

§ Post-developed Condition

§ Alter imper vious/ per vious ar eas to r eflect development § Run fir st iter ation of pond § Optimize pond sizing § Autopond sizing

§ Summar y

Pr Project

• ject Ass

Assump umptio tions ns

§ Develop apar tments on tax lot 9000, 91

00 and 9200

§ Pr e-developed Condition

§ Pasture 3.92 acr es

§ Post-developed Condition

§ 74,300 sqft (1

.70 acr es) r oof

§ 45,1

00 sqft (1 .04 acr es) parking

§ 51

,400 sqft (1 .1 8 acres) landscape

§ Development tr igger s Categor y 3 or NMFS

r equir ements for flow-dur ation cur ve matching BMP

City of Beaverton GIS S ystem

Pr Project

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Examp ample le Loc Locati ation

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Pr Pre-De e-Devel velop

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ed Con Conditi dition

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All vegetation assumed to be pasture.

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Use NRCS to classify soil types.

Type C/ D

US DA National Resource Conservation S ervice Websoil S urvey

Pr Proje

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ct Exa Example ple – Pr Pre-De e-Deve velop loped ed Basin Basin

Pr Proje

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ct Exa Example ple – Deve Develop loped ed Basin Basin

Pr Proje

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ct Exa Example ple – Det Detent entio ion n Basin Basin

Pr Proje

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ct Exa Example ple – Det Detent entio ion n Basin Basin

Pr Proje

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ct Exa Example ple – Det Detent entio ion n Basin Basin

50% 2yr Pre

Pr Proje

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ct Exa Example ple – Det Detent entio ion n Basin Basin

50% 2yr Pre

Project Example – Optimizing Pond Size

50% 2yr Pre

Pr Proje

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ct Exa Example ple – Pond

• nd Aut

Autosi

• sizer

50% 2yr Pre

Summ Summary ary

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Key Design Par ameters §

Max ponding depth

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Water way side slopes (e.g. 3:1 , 4:1 )

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Or ifice size(s)

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Weir elevation, width

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Weir notch depth/ width

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Focus on 50% of the 2yr event fir st

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Use AutoPond as a star ting point and adjust or ifice and weir to optimize the BMP sizing. §

With AutoPond Footpr int – 1 30’ x 1 30’

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Without AutoPond Footpr int 1 20’ x 1 20’

Ag Agenda enda

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Intr oduction to TRUST and Continuous Simulation Modeling

§

Continuous Modeling Example

§

Applications of TRUST by Clean Water Ser vices

TRUS TRUS T T Appli Applica cation tions s by by CW CWS Ov S Overview erview

§ Subbasin planning § Hydromodification strategy development § Standardizing the checking of facility sizing during plan review

Subb Subbasin asin Plann Planning ing

§ Predicting and quantifying effects of development § Evaluating and selecting strategies § Adaptive management.

§ Development never goes exactly as planned

TRUS TRUS T T in in Subba Subbasi sin n Plann Planning ing

§ Continuous simulation

§ More information, more accurately § BMP and stream inundation frequencies § Routing § Antecedent moisture § Design flow vs design rainfall § Use real storm events or integrate

• ver long periods

0.5 1 1.5 2 2.5 3 3.5 11/ 29/ 1994 11/ 30/ 1994 12/ 1/ 1994 12/ 2/ 1994 Flow (cfs)

TRUS TRUS T T in in Subba Subbasi sin n Plann Planning ing

§ Ease of use.

§ Much easier representation of BMPs than regular HSPF § Pre-calibrated § Easily compare different BMP types § GUI is more intuitive for beginning users than regular HSPF § BMP auto-sizing algorithms

TRUS TRUS T T in in Subba Subbasi sin n Plann Planning ing

§ Uniformity.

§ Same platform § Same calibration § Same land use categories § Same rainfall data § Same statistical methods

Subb Subbasin asin Plann Planning ing Pr Projec

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t Case Case Stu Study dy

Moved BMP locations Evaluate a range of in- stream strategies and combinations Rapidly developing Interim BMPs/ Retrofits

Hy Hydr drom

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ficat ation ion Str Strat ateg egy y Dev Develo elopm pmen ent

Distributed Regional Stream Enhancement

Hy Hydr drom

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ficat ation ion Str Strat ateg egy y Dev Develo elopm pmen ent

§ All three strategies can be modeled

§ Individually or in combinations

§ TRUST can also provide hydrologic inputs to more detailed hydraulic models

§ e.g. 2D HEC-RAS

§ Compare single (real) storm and/or long-term performance

Hy Hydr drom

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ificatio tion n Str Strategy egy Dev Devel elopm

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t Case Case Study Study

In-line detention (in series) Riparian wood/ vegation In-stream wood/ vegation Real-time Control S wales / detention basins

S tan S tandar dardi dized ed Plan Plan Revie eview

Developers not required to use TRUST, but: § Speeds up and simplifies the plan review process § Avoids confusion of applicability of standards § Internal tools provide check on calculations and help avoid errors § New functionality coming

§ New BMPs § Possibly more sizing methods

Than Thank k you!

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Questions?

Chris Hass, PE Stormwater Consultant – OR 503-807-2322 CHass@ContechES.com Scott Mansell, PhD, PE Senior Engineer 503-681-4466 MansellS@CleanWaterServices.org Doug Beyerlein, PE, PH, D.WRE Principal Engineer 425-225-5997 beyerlein@clearcreeksolutions.com