1. Southeast
Environmental
Research Center
WATER QUALITY MONITORING PROJECT FOR DEMONSTRATION OF CANAL REMEDIATION METHODS FLORIDA KEYS
Report of activities: Assessment of Canal Remediation Methods using Water Quality Data Before and After Remediation
July 15, 2016
Presented to:
Water Quality Program Canal Restoration Advisory Committee
Henry O. Briceño, Alexandra Serna,
Michael Absten, Sandro Stumpf, James Duquesnel

2. Southeast Environmental Research Center
Objective
To provide data needed to make unbiased, statistically rigorous statements about the status and temporal trends of water quality parameters in the remediated canals
Conceptual model
The execution of the project includes two phases:
Before remediation
After remediation

3. Southeast Environmental Research Center
Water quality testing parameters
Vertical profiles
Continuous 24-hour recording (Diels) of physical-chemical data:
%DO (Dissolved Oxygen) sat exceedances calculations: % readings below 42% saturation in a full day of diel data
Water sampling for total nutrients analysis

4. Southeast Environmental Research Center
Water quality target
DO (Dissolved Oxygen) criteria for Class III Waters
Minimum DO saturation levels shall be as follows:
1. The daily average % DO saturation shall not be below 42 % saturation in more than 10 % of the values
2. The seven-day average DO % saturation shall not be 56 % more than once per year

5. Southeast Environmental Research Center
Project
Canal #
Model Zone
TP (µg/l)
TN (µg/l)
Backfilling 29 9N 11
764
CONTROL 28
Weed Barrier
137 8N
132
Culvert installation
472 3S 8
138
Connection to 472-NEW
470
458
287 4N 12
221
Organic removal
290
Weed Barrier / organic removal
266
293
277
282
148
147
Pumping
278
459
Connection to 459 -NEW
460
Water quality target according to the FKRAD program
Nutrient concentration, Total Phosphorus (TP) and Total Nitrogen (TN) according to model zones

6. Southeast Environmental Research Center
Tasks completed
Legend: D (3-day Diels), S&B (Surface and Bottom water), N (Nutrient analysis)
Project
Canal #
Model Zone
FKC-01
FKC-02
FKC-03
FKC-04
FKC-05
FKC-06-Phase I
FKC-06-Phase II
Backfilling 29 9N
31-Mar-14
16-Oct-14
3-Jul-15
4-Feb-16
28-Apr-2016 D S&B
CONTROL 28
27-Mar-14
Weed Barrier
137 8N
7-May-14
4-Nov-14
20-Jul-15
19-Feb-16
132
Culvert installation
472 3S
9-May-14
15-Oct-14
22-Apr-15
29-Apr-15
30-Jun-15
20-May-16
Culvert plugged July 2015
 Culvert unplugged May 2016
Connection to 472-NEW
470
16-May-16
458
17-Feb-16
Air Curtain Weed Gate
287 4N
14-Oct-14
24-Jun-15
11-Feb-16
6-Jun-16
21-Jun-16 D S&B
Organic removal (air curtain by homeowners)
290
11-Mar-16
24-Jun-16 D S&B
Weed Barrier / organic removal
266
16-Jan-16 (muck removal)
20-May-2016 Weed Barrier
293
18-Feb-16
277
20-Apr-16
30-Jun-2016 D S&B
282
148
147
Pumping
278
459
Connection to 459 -NEW
460

7. Southeast Environmental Research Center
Demonstration canals included in this report
First project: Backfilling at Canal #29 in Sexton Cove in Key Largo. Completed in July 2015.
Second project: Culvert Installation to connect Canals #472 and #470, on Geiger Key. Completed in April 2015.
Third project: Combined Organic Removal and Air Curtain Installation on Canal #266 at Drs. Arm and Avenue J in Big Pine Key. Completed in May 2016.
FIU photo by J. Duquesnel – Canal #472

8. Southeast Environmental Research Center
Demonstration canals included in this report
Fourth project: Organic Muck Removal Project on Canal #290 Avenue I on Big Pine Key. Completed in March 2016.
Fifth project: Installation of a culvert under a roadway and private property connected two portions of Canal #277. Completed in May 2016.
Sixth project: Air Curtain Weed Gate Installation for Canal #287 in Atlantic Estates on Big Pine Key. Completed June 2016.
FIU photo by J. Duquesnel – Canal #472

9. Southeast Environmental Research Center
Canal #29. Remediation technology: Backfilling. Completed Jul-15
LEGEND
Oxygenation has improved significantly
Favorable value above WQ target
Negative value below WQ target
Surface waters well oxygenated in most events before and after remediation
Surveys showed increase %DO saturation in shallower new bottom waters after the canal's depth was risen from 35 feet to 8 feet

10. Southeast Environmental Research Center
Canal #29. Remediation technology: Backfilling. Completed Jul-15
LEGEND
Favorable value above WQ target
Negative value below WQ target
TN show signs of improvement while TP still remain too high
Pre-remediation and first post-remediation surveys rendered TP concentrations out of compliance
Surface and Bottom TN concentrations in compliance in all events before and after remediation

11. Southeast Environmental Research Center
Canal #472. Remediation technology: Culvert installation. Completed May-15 and was closed shortly after, unplugged May-16
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface waters well oxygenated during monitoring before and after remediation. Heavy seaweed build up observed in late May 2015
%DO saturation increased in bottom waters of remediated canal when culvert was opened the first time indicating an enhancement of natural tidal flushing

12. Southeast Environmental Research Center
Canal #472. Remediation technology: Culvert installation. Completed May-15 and was
closed shortly after, unplugged May-16
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface and Bottom TP concentrations out of compliance in most events before and after remediation
Pre-remediation surveys rendered TN concentrations out of compliance

13. Southeast Environmental Research Center
Canal #266. Remediation technology: Weed barrier/organic removal. Completed May-2016
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Pre and post-remediation surveys showed highly variable %DO saturation in surface waters
Pre and post-remediation surveys rendered %DO saturation in bottom waters out of compliance

14. Southeast Environmental Research Center
Canal #266. Remediation technology: Weed barrier/organic removal. Completed May-2016
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface and Bottom waters rendered TP concentrations out of compliance before remediation
Pre-remediation surveys rendered TN concentrations out of compliance

15. Southeast Environmental Research Center
Canal #290. Remediation technology: Organic removal. Completed Mar-16.
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface waters do not meet %DO saturation target either in most events during monitoring before or after remediation. Notice that an existing air curtain weed gate owned by the homeowners was reinstalled but it allowed some seaweed to enter the remediated canal
%DO saturation in bottom waters of remediated canal remains below target values in the first event after completion of vacuum dredging process to remove 5 feet of organic muck. Following removal of the much, a 6-inch sand layer was added to allow for benthic habitat proliferation

16. Southeast Environmental Research Center
Canal #290. Remediation technology: Organic removal. Completed Mar-16.
LEGEND
Favorable value above WQ target
Negative value below WQ target
Waiting for test results
Surface and Bottom waters rendered TP concentrations out of compliance before remediation
Pre-remediation surveys rendered TN concentrations out of compliance

17. Southeast Environmental Research Center
Canal #277. Remediation technology: Culvert installation. 20-Apr-2016
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface waters well oxygenated in most events during monitoring before and after remediation. Water clarity with fish visible at the culvert entrance (MC, Jun 2016), although no differences in turbidity in S/B water has been observed after remediation (data no presented here)
Lots of blue-green algae mat floating on surface (#282) and lots of (floating) Manatee Grass present in canal #277
%DO saturation in bottom waters of remediated canal remains below target values approx. 2 months after culvert was opened the first time

18. Southeast Environmental Research Center
Canal #277. Remediation technology: Culvert installation. 20-Apr-2016
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface and Bottom TP concentrations out of compliance in most events before remediation
Pre-remediation surveys rendered TN concentrations out of compliance

19. Southeast Environmental Research Center
Canal #287. Remediation technology: Weed barrier. Completed Jun-16
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface waters well oxygenated during monitoring before and after remediation.
%DO saturation in bottom waters of remediated canal remains below target values two weeks after the installation of the air curtain weed gate. Lots of suspended organic debris, settled on floats and sondes

20. Southeast Environmental Research Center
Canal #287. Remediation technology: Weed barrier. Completed Jun-16
LEGEND
Favorable value above WQ target
Negative value below WQ target
No definitive improving trend yet
Surface and Bottom waters rendered TP concentrations out of compliance before remediation
Pre-remediation surveys rendered TN concentrations out of compliance

21. Southeast Environmental Research Center
Tentative work schedule
Project
Canal #
FKC-07
Backfilling 29
25-Jul-16 D&N S&B
CONTROL 28
Weed Barrier
137
132
Culvert installation
472
Connection to 472-NEW
470
458
Air Curtain Weed Gate
287
7-Aug-16 D S&B
Organic removal (air curtain by homeowners)
290
Weed Barrier / organic removal
266
293
277
282
Legend: D (3-day Diels), S&B (Surface and Bottom water), N (Nutrient analysis)

22. Tentative deliverables schedule
Southeast Environmental Research Center
Tentative deliverables schedule
Task
Due date following work execution
Deliverable
Quarterly monitoring FKC-06
90 days
Progress report
Reporting
90 days of the period end date
Bi-annual report
Quarterly monitoring FKC-07
Quarterly monitoring FKC-08
Quarterly monitoring FKC-09
90 days of the project period end date
Final report