1. Dam Safety Program March 2011 Dam Safety Program March 2011

3. Dam Safety Program Activities Recurrent Dam Safety Activities Structures Assessments and Repairs Dam Rehabilitation CENTENNIAL NARROWS DAM 1997 DAM FAILURE

4. Background Flood Control District Dams –District Operates and Maintains 22 Flood Control Dams –16 Dams Built by Natural Resources Conservation Service (NRCS - Formerly SCS) –5 Dams Built by Corps of Engineers –1 Designed and Built by District –Dams Total 64 Miles in Length –District was local Sponsor for NRCS and Corps Dams –Arizona Department of Water Resources is the Jurisdictional Agency

5. Background 16 NRCS Dams  Built From 1954 to 1991  100-Year Flood Protection for Agricultural Areas  Flood Storage: Average 3,000 Acre-Feet Maximum 11,000  Most Single Zone Earthen Dams, Average Length 3.2 miles 4 Corps of Engineers Dams, District as Sponsor  Built From 1974 to 1985  SPF Flood Protection for Urbanized Areas  Flood Storage: 300, 18,000, 43,000 47,000 Acre-Feet  Zoned Earthen Dams, Average Length 0.8 miles McMicken Dam – USACOE, 1956 McMicken Dam – USACOE, 1956 Cassandro Wash Dam –District, 1996 Cassandro Wash Dam –District, 1996

6. Recurrent Dam Safety Activities Dam Surveys

7. Recurrent Dam Safety Activities Future Contracts Surveys for DamsSurveys for Dams On-call Register Based SelectionOn-call Register Based Selection Contract Value $250,000Contract Value $250,000 Contract Duration 2 YearsContract Duration 2 Years Anticipated Award Dates: Anticipated Award Dates: –TBD

8. Recurrent Dam Safety Activities Future Contracts Upgrade of Emergency Action Plans – Now performed in Engineering DivisionUpgrade of Emergency Action Plans – Now performed in Engineering Division On-call Register Based SelectionOn-call Register Based Selection Contract Value $250,000Contract Value $250,000 Contract Duration 2 YearsContract Duration 2 Years Anticipated Award Dates: Anticipated Award Dates: –TBD

9. Structures Assessments and Repairs McMicken Dam Embankment Cracking at Principal Spillway

10. Structures Assessments and Repairs Guadalupe FRS Intake Structure and Gates Guadalupe FRS Intake Structure and Gates Outlet Cracking Outlet Cracking Buckeye FRS No.2 Dam Safety Deficiency Buckeye FRS No.2 Dam Safety Deficiency PMP/PMF Updates From Statewide PMP Study PMP/PMF Updates From Statewide PMP Study Gravel Mulch added to Dams Gravel Mulch added to Dams Other Dam Safety Issues by need and priority Other Dam Safety Issues by need and priority

11. Structures Assessments and Repairs Future Contracts Geotechnical On-call: $500K to $750K, 2 to 3 Years, Advertise: 2 to 3 monthsGeotechnical On-call: $500K to $750K, 2 to 3 Years, Advertise: 2 to 3 months Civil/Geotech/H&H On-call: $500K to $750K, 2 to 3 Years, Advertise: 2 to 3 monthsCivil/Geotech/H&H On-call: $500K to $750K, 2 to 3 Years, Advertise: 2 to 3 months

12. Dam Rehabilitation and Dam Modifications Overall dams are well maintainedOverall dams are well maintained Recurrent dam safety activities and structures assessment are keeping the dams safe to operate for the short term and interim termRecurrent dam safety activities and structures assessment are keeping the dams safe to operate for the short term and interim term 2 Dam Rehabs Completed2 Dam Rehabs Completed 6 Dams identified for rehabilitation or replacement for dam safety reasons6 Dams identified for rehabilitation or replacement for dam safety reasons 3 Dams identified for modifications3 Dams identified for modifications

13. Dam Rehabilitation Projects Status  Spook Hill FRS Rehab – Complete  White Tanks FRS No.3 Rehab - Phase II Construction  White Tanks FRS No.4 Rehab  Phase I Construction – March 2011  Phase II – Final Design in progress  Buckeye FRS No. 1 Rehab– Final Design in progress  Powerline FRS, Vineyard Road FRS and Rittenhouse FRS – Planning in Progress – FUTURE DESIGN CONTRACT  McMicken Dam – District planning complete, seeking Corps funding – FUTURE DESIGN CONTRACT

14. Dam Modifications Projects Status  Powerline FRS Earth Fissure Mitigation – Construction March 2011 Construction March 2011  Saddleback FRS Filter Repair – Final Design in Progress  Cave Buttes Dam Modifications – Final Design in Progress