ms4 practices assessment phase iii (with review of

MS4 Practices Assessment Phase III (with review of previous Phase II)

Maintenance Matters !

PRELIMINARY DRAFT RESULTS

Florida Department of Environmental Protection and Florida Stormwater Association

andUniversity of Florida

Engineering School of Sustainable Infrastructure and Environment (ESSIE)

John Sansalone ([email protected])

Overall Project Objectives and OutcomesPrimary objective is a Florida-based “yardstick” or metrics to allow an MS4 to more robustly quantify N, P loads (and generate load credits) through separation and recovery of particulate matter (PM) for typical urban infrastructure systems inside and outside wastewater reuse areas:1. Pavement systems cleaning (pavement street sweeping), 2. Catch basins (inlets), 3. “BMP “ (the most utilized and cleaned BMPs for an MS4)

• Outcomes are Florida-based metrics (a statistic of the resulting probability distributions: i.e. median) based on 12 MS4s

• Outcomes allow dry-equiv. load of PM separated (i.e. a BMP) and then recovered by maintenance to be converted to N, P loads

• Outcomes quantified by land use or independent of land use• Outcomes quantified for areas w/wastewater reuse and without (control)

Specific Project Objectives with Tasks and Outcomes

1. The reclaimed water enrichment (N, P) of PM recovered from maintenance operations of hydrologic functional units (HFUs):

Tasks and Outcomes:1. PM sampling by MS4s for paired locations, inside/outside reclaimed water areas,

2. Sampling by MS4s of AWT, WWTP effluent paired w/reclaimed water area samples,

3. Sampled land uses: residential, commercial, highway - consistent w/Phase II study,

4. Sampled hydrologic functional units: SS, CB, BMPs - consistent w/Phase II study,

5. Samples outside of reclaimed water areas serve as the control samples,

6. Nutrient analysis of recovered PM and final effluent will include TP and TN,

7. Florida-, HFU-, land use-based distributions/summary metrics for reclaimed water areas as compared to control (outside reclaimed water areas).


2. Nutrient enrichment of specific particulate matter (PM) size fractions:

Tasks and Outcomes:

1. PM samples will be size-fractionated into:

a. > 2 mm (debris, gravel-size PM, detritus, biogenic materials such as leaf litter),

b. 0.075 mm (#200 sieve) to 2 mm, for the coarse fraction of PM,

c. < 0.075 mm, for the fine fraction of PM, when sufficient PM is available

2. Nutrient analysis will be conducted on each of these size fraction,

3. Test if PM size fractions enriched by TP, TN compared to outside reclaimed water areas,

4. Water content and volatile fraction analysis conducted on each size fractions,

5. Analyze particle size distributions (PSD) to identify relative mass of these size fractions,

6. Florida-, HFU- and land use-based distributions and summary metrics for all areas,


3. The leaching of PM by “stormwater” (urban drainage):

Tasks and Outcomes:

1. Nutrient leaching/sorption endpoints for inside/outside reclaimed water areas in only GNV, UF will have to work with GNV on the appropriate and additional sampling,

2. TP/TN leaching or sorption rates of PM for aerobic conditions in wet sumps,

3. TP/TN leaching or sorption rates of PM for anoxic/anaerobic conditions in wet sumps,

4. Leaching/sorption rates of PM for moist conditions of “dry” BMP or CB sumps; or SS,

5. The outcome from this objective is to assess a maintenance interval so that TP/TN can be retained and recovered with PM as opposed to being leached into urban drainage.


4. A PM water content nomograph (quantify water associated with PM)

Tasks and Outcomes:

1. Produce a probability distribution and metric for water content as a function of HFUs and land use,

2. Produce a water content metric for the 3 PM size fractions and biogenic materials such as leaf litter,

3. Create water content nomograph (a tabular or graphical plot) for PM of SS at recovery based on available MS4 weather data,


5. A 2nd generation FSA interactive spreadsheet tool for MS4 load credits:

Tasks and Outcomes:

1. Create and test a 2nd generation synthesis spreadsheet with input from MS4s, FDEP, FSA,

2. Provide two interactive educational seminars at summer FSA conferences,

3. The outcome is a public tool (spreadsheet) and seminar-based guidance for Florida MS4s to quantify PM, N, P, load recovery and credits.

Phase III (and II) focuses on PM-phase N and P loads(PM-phase N and P control directly impacts aqueous phase N and P)

Particle Diameter, D (m)

{cdf

}: %

fine

r by

mas

s, F(

D)

0

20

40

60

80

100

Dry Depositionq (up)

q (down)

downstreamupstream

q (settled)

110100100010000

)(/)(

/1

DeDDf

)(/)()( DDF

0

)(1)( dxex x

D x

D dxex0

)(1)(

PSD gamma model

PSD of

PM

DDPavementDeposition

q (up)CB or inlet

Runoff

q (down)BMP influent

Runoff

q (settled)BMP effluent

RunoffD50m 331 μm 99 μm 23 μm 14 μm

PM: Particulate

Matter

BMP: Clarifier with 1 hr. of quiescent settlingLocation (γ, β) DD (2.06, 187.7)

q (up) (1.90, 61.9)

q (down) (1.23, 23.6)

q (settled) (1.51, 11.1)

Review of Phase III Methodology

1. For physical sampling and analytical laboratory analyses the methodology is the same as Phase II

2. For Phase III the samples received to date (14 June 2018) and the categorical distribution of samples is shown in the following slides

3. The total number of samples in any one category is smaller than Phase II given that Phase II only focused on outside of reclaimed areas where one objective of Phase III is to directly compare samples from reclaimed areas (IN) to samples from outside of reclaimed areas (OUT)

Code Full name Population Land area

APF Naples 21,845 42.59 km2

BC Brevard County 589,162 4,033 km2

EC EscambiaCounty 315,187 2,266 km2

GNV Gainesville 124,354 164.43 km2

LC Lee County 739,224 3,139 km2

MCO Orlando 277,173 294.61 km2

OC Orange County 1,348,975 2,598 km2

PIE St. Petersburg 260,999 356.50 km2

SAC Sarasota County 51,917 65.31 km2

SEC Seminole County 449,144 894 km2

ST Stuart 16,623 23.31 km2

VC Volusia County 517,887 3,710 km2

Phase III Participating MS4s

Total project PM samples (n = 406/505)

IN(n = 205/256)

BMP (n = 77/92)

CB (n = 67/82)

SS (n = 61/82)

OUT(n = 201/249)

BMP (n = 68/82)

CB (n = 71/85)

SS (n = 62/82)

Total project PM samples (n = 406/505)

IN(n = 205/256)

R (n = 78/92)

H (n = 58/81)

C (n = 69/83)

OUT(n = 201/249)

R(n = 67/83)

H (n = 63/81)

C (n = 71/85)

Sample delivery (as samples analyzeda/target # of samples)

a. APF (12) and PIE (24) samples are currently under analysis.b. Duplicates not tabulated in these numbers

HFUbasis

Land Usebasis

MS4 Samples No. of samples still required Notes (Labels of missing samples)

PIE PM 12

PIE_BMP_H_IN_1; PIE_BMP_H_IN_2;PIE_BMP_H_OUT_1; PIE_BMP_H_OUT2PIE_CB_C_IN_1; PIE_CB_C_OUT_2PIE_BMP_R_OUT_2; PIE_BMP_C_IN_2PIE_CB_H_IN_1; PIE_CB_R_OUT_1

Stormwater 4 Runoff (t = 0, 5, 10, 15)

OCPM 36 All the metric labels

Stormwater 4 Runoff (t = 0, 5, 10, 15)WWTP + Discharge 2 1 WWTP effluent + 1 Discharge sample

EC Stormwater 4 Runoff (t = 0, 5, 10, 15)WWTP + Discharge 1 1 Discharge sample

SEC PM 12 All SS samples (waiting for delivery from Sanford)

ST PM 3 ST_BMP_H_IN_2; ST_CB_H_IN_2; ST_SS_H_IN_2

APF Stormwater 4 Runoff (t = 0, 5, 10, 15)SAC Stormwater 4 Runoff (t = 0, 5, 10, 15)

MS4 sample deliverables that remain as of 14 June 2018

Review of Preliminary Primary Phase III Results

1. Results presented are from outside (OUT) reclaimed wastewater areas and inside (IN) reclaimed area results; this is different from Phase II that only suggested such a comparison

2. Results are either composited by combining separate land use results or combining separate HFU (SS, CB, BMP) results or both; OR results are delineated as a function of land use and HFU. For brevity only summary results are illustrated.

3. Land uses: – “Highway” (H) {major transportation R/W} – Residential (R) – Commercial (C)

Non-parametric statistics of particle size distribution (PSD) for IN and OUT data.

Particle diameter, d (m)1101001000

% F

iner

by

mas

s

0

20

40

60

80

100

Raw PSDMedian of PSD

n = 406

d10 (μm) 199.4d50 (μm) 580.5d90 (μm) 2642.9

α (Shape) 1.89β (Scale) 364.99

Median of PSD

CGD

Settl

eabl

e25

m

~ 7

5 m

Sedi

men

t>

75

m

Susp

ende

d<

25

m

Entire PSD(IN + OUT data)

Wilcoxon rank sum test (α = 0.05) WC for entire PSD WC for PM >2000 μm WC for PM < 2000 μm

Result SS < CB = BMP SS < CB < BMP SS < CB < BMP

Non-parametric statistics of water content (WC) for HFUs

WC % =mwatermdry

100%mdry: mass of dry sample; mwater: mass of water

Wilcoxon rank sum test (α = 0.05) WC for entire PSD WC for PM >2000 μm WC for PM < 2000 μm

Result IN > OUT IN > OUT IN > OUT

Non-parametric statistics of water content (WC) for street sweeping (SS)

WC % =mwatermdry

100%mdry: mass of dry sample; mwater: mass of water

Non-parametric statistics of total nitrogen (TN) for hydrologic functional units (HFUs)

Wilcoxon rank sum test (α=0.05) TN for entire PSD TN for Sediment TN for Settleable TN for Suspended

Result SS < CB < BMP SS < CB < BMP SS < CB < BMP SS < CB = BMP

Non-parametric statistics of total nitrogen (TN) for inside and outside reclaimed area


Result IN = OUT IN = OUT IN = OUT IN = OUT

Non-parametric statistics of total phosphorus (TP) for hydrologic functional units (HFUs).


Result BMP = SS = CB BMP = SS = CB SS < BMP = CB SS < BMP = CB

Non-parametric statistics of total phosphorus (TP) for inside and outside reclaimed area

Wilcoxon rank sum test (α=0.05) TP for entire PSD TP for Sediment TP for Settleable TP for Suspended

Result IN = OUT IN = OUT IN = OUT IN = OUT

Comparison of TN concentration between Phase II and Phase III for IN and OUT data.

Wilcoxon rank sum test (α=0.05) TN for IN data TN for OUT data

Result Phase II ≤ Phase III Phase II = Phase III

Comparison of TP concentration between Phase II and Phase III for IN and OUT data.

Wilcoxon rank sum test (α=0.05) TP for IN data TP for OUT data

Result Phase II > Phase III Phase II = Phase III

Savings to MS4s based on SS reported compared to implementation of BMPs for equivalent load recovery

1. Use of FDEP database on street sweepings for reporting Florida MS4s

2. Results based on Phase II results

Economics of separation/recovery of PM, TN and TP from SS, CB and BMPs based on Phase II results

Separation and/or recovery methoda Median cost ($/lb.)TN TP PM

Street sweeping (SS) 165 257 0.10Catch basin (CB) cleaningb 1,016 1,656 0.70

FL database for BMPsc 1,900 10,500 41a. For BMPs, separation and recovery are required, while only recovery is required for maintenance practices.b. Based on 100 dry pounds of PM recovery based on an annual cleaning frequencyc. TMDL database for Florida Best Management Practices, 2009

HFUWater Content, WC

(%) TN

[g/kg]TP

[g/kg]Median Range Median STD Median STD

SS 5.9 72.9 0.6 1.4 3.6 0.6CB 21.3 87.6 0.7 2.6 4.2 0.5

BMP 26.0 72.9 0.9 4.0 3.6 0.7

Economics of PM recovery method (SS vs equivalent BMPs for load) and associated nutrients from Orange County

Note: SS reported as mass (tons)

Economics of PM recovery method (SS vs equivalent BMPs for load) and nutrients based on entire FDEP database for reporting MS4s

Impact of maintenance interval on PM removal efficiency(Results validated with actual events of return periods at ~ 1 month)

Treatment Train:• Primary (Type I)

settling followed by secondary filtration

Clarification Basin:• Primary (Type I)

settingScreened HS:• Primary (Type I)

setting and size exclusion by screen

Screened HS function governed by cleaning interval, whereas treatment train can be governed by head loss

Storm-driven Computational Fluid Dynamics for BMP Behavior

1. Consistent with Phase II, Phase III results to date recommends continued use of a median (50th percentile) concentration [mg or g/kg] from each measured TN and TP distribution,

2. This result is important for allocation of load credits because the results are not represented by a singular concentration [mg or g/kg] but by distributions of concentration,

3. Results to date from Phase III indicate that reclaimed wastewater does not enrich urban PM and detritus with TN (similar to Phase II) and TP (different from Phase II) noting that Phase II only compared three MS4s for inside vs. outside at reclaimed wastewater areas,

4. Economy of load recovery by street sweeping is significantly lower than separation/recovery by BMPs (manufactured and non-proprietary) which are still needed, even assuming such BMPs are maintained annually and do not scour/washout. (See previous $/pound slide),

5. Economics not withstanding, volumetric/hydrologic control systems and BMPs are still required but require regular maintenance, optimization, retrofitting through existing tools such as computational fluid dynamics (CFD) and continuous simulation modeling (SWMM)

6. MS4s can benefit from efforts focused on street sweeping for load recovery and source control while optimizing/retrofitting/maintaining volumetric/hydrologic control and BMPs

Phase III draft conclusions to date

ms4 practices assessment phase iii (with review of

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